Loading...
HomeMy WebLinkAboutCT 07-05; LA COSTA GREENS NEIGHBOROOD 1.3; DEVELOPED CONDITION DRAINAGE STUDY; 2008-08-05I I I I I I I I I I I I I I I I I II - PLANNING ENGINEERING SURVEYING IRVINE LOS ANGELES RIVERSIDE SAN DIEGO ARIZONA DAVE HAMMAR LEX WILLIMAN ALiSA VIALPANDO DAN SMITH RAY MARTIN CHUCK CATER 9707 Waples Street San Diego, CA 92121 (858) 558-4500 PH (858) 558-1414 FX www.Hunsaker5D.com Info@HunsakerSD.com HUNSAKER &ASSOCIATES 5 AND lEG 0, INC. DEVELOPED CONDITION DRAINAGE STUDY for LA COSTA GREENS NEIGHBORHOOD 1.3 City of Carlsbad, California CT 07-05 Prepared for: Col rich Communities 4747 Morena Blvd. Suite 100 San Diego, CA 92117 w.o. 2301-15 August 5, 2008 41st David A. Blalock, R.C.E. Hunsaker & Associates San Diego, Inc. RE ,c H \REPORTSI230111 SIDEV COND HYDRO·03 doc W.O 2301·15 8/512008102 PM -= .--w "-= I I I I I I I I I I I I I I I I II I I Developed Condition Drainage Study La Costa Greens 1.3 TABLE OF CONTENTS SECTION Chapter 1 -Executive Summary 1.1 Introduction 1.2 Existing Condition 1.3 Developed Condition 1.4 Summary of Results 1.5 References Chapter 2 -Methodology & Model Development 2.1 City of Carlsbad Engineering Standards 2.2 County of San Diego Drainage Design Criteria 2.3 Design Rainfall Determination 100-Year, 6-Hour Rainfaliisopiuvial Map 100-Year, 24-Hour Rainfall Isopluvial Map 2.4 Runoff Coefficient Determination 2.5 Rainfall Intensity Determination Maximum Overland Flow Length & Initial Time of Concentration Table Urban Watershed Overland Time of Flow Nomograph -Gutter & Roadway Discharge-Velocity Chart Manning's Equation Nomograph Intensity-Duration Design Chart 2.6 Rational Method Model Development Summary Chapter 3 -Rational Method Hydrologic Analysis (100-Year Developed Condition AES Model Output) Chapter 4 -Storm Drain Hydraulic Analysis Chapter 5 -Inlet Sizing Chapter 6 -Hydrology Map Appendix -"Drainage Study for La Costa Greens Neighborhoods 1.2 & 1.3 Developer Improvements"; Hunsaker & Associates, August 2006 II III IV v VI RE.kc H:IREPORTS\2301115IOEV COND HYDRO·03.doc w.o.2301·15 8/5/20081'02 PM I 'I '1' il I' I ·1 I I ·'1 ,I I I I I. ·1 I I· I I I I I I I I I I I· I I I I I I I I I I Developed Condition Drainage Study La Costa Greens 1.3 EXECUTIVE SUMMARY 1.1 -Introduction The La·Costa Greens Neighborhood 1.3 site is located north of Poinsettia Lane and west of Alicante Road in the City of Carlsbad, California. The project site is also bound by EI Camino Real directly to the west (see Vicinity Maps on this page). All runoff from the site and surrounding improvements will drain southeast to the Alicante Detention Basin, located on the southeast corner of the Poinsettia Lane- Alicante Road intersection, ultimately draining to an unnamed tributary of San Marcos Creek. Runoff from this tributary eventually discharges into San Marcos Creek towards the Batiquitos Lagoon. VICINITY MAP 1175 LA COSTA VICINITY MAP Mrs This study analyzes 1 DO-year developed conditions peak flow rates from the proposed La Costa Greens Neighborhood 1.3 site. The site has been mass graded per the "Grading & Erosion Control Plans for La Costa Greens Neighborhoods 1.01- 1.03" prepared by Hunsaker & Associates. RE:kc H:IREPORTSI2301\15IDEV COND HYDRO-03 doc w.o.2301-15 8/5/20081 02 PM -' I I I I I I I I I I I I I I I I I I II Developed Condition Drainage Study La Costa Greens 1.3 Treatment of storm water runoff from the site has been addressed in a separate report -the" Storm Water Management Plan for La Costa Greens Neighborhoods 1.3", prepared by Hunsaker & Associates and dated July 2008. 1.2 -Existing Condition The La Costa Greens Neighborhood 1.3 site is part of the La Costa Greens development in the City of Carlsbad, California. The existing La Costa Greens 1.3 site has been mass-graded per the "Grading & Erosion Control Plans for La Costa Greens Neighborhoods 1.01-1.03". . Runoff from the mass-graded La Costa Greens Neighborhood 1.3 residential site ' flows into a desiltation basin located in the southwest corner of the mass-graded site. The runoff then flows southeasterly towards Poinsettia Road, where it is intercepted via an existing U-Type headwall at approximate Sta. 23+00 per Dwg. No. 397-2H, and then via storm drain beneath Poinsettia Road to the Alicante Detention Basin located in the southeast corner of the Poinsettia Lane-Alicante Road intersection. The peak discharge from this basin is drained by a double 8-ft by 5-ft reinforced concrete box and then flows southwards to an unnamed tributary of San' Marcos Creek. The runoff then flows in a southerly direction along the site boundary of the La Costa Greens Golf Course, west of the Phase I development area. All the "runoff eventually drains under Alga Road via three 96" RCP culverts, as shown in Drawing No. 397-2, and discharges into San Marcos Creek towards the Batiquitos Lagoon. The existing condition hydrologic analysis of the La Costa Greens 1.3 development was completed and is discussed in the "Drainage Study for La Costa Greens Neighborhoods 1.2 & 1.3 Developer Improvements", prepared by Hunsaker & Associates dated August 21, 2006. The report in its entirety has been included within this drainage study as an appendix. The Regional Water Quality Control Board has identified San Marcos Creek as part of the Carlsbad Hydrologic Unit, San Marcos Hydrologic Area, and the Batiquitos Hydrologic Subarea (basin number 904.51). 1.3 -Developed Condition The construction of the La Costa Greens Neighborhood 1.3 site will include 38 single family units with associated car parking, internal storm d~ain systems, sidewalks, and a single entrance from the adjacent EI Camino Real to the west of the project site. RE.kc H:IREPORTSI2301l15IDEV COND HYDRO·03 doc W.O 2301-15 8/5/2008'1:02 PM I I I I I I I I I I I I I I :1 I I I I Developed Condition Drainage Study La Costa Greens 1.3 The majority of the runoff from the developed site will be collected and conveyed via a curb and gutter system into a storm drain system within the project site_ The storm drain system flows in a southerly direction, discharging into an onsite water quality basin_ The runoff in the bas'in discharges via an existing 24" storm drain and surface flows in a southerly direction, along the site boundary of the La Costa Greens Golf Course until it eventually drains under Alga Road via three 96" RCP culverts and discharges into the existing Alicante Detention Basin. The remainder of the runoff will be collected in a curb and gutter system and conveyed northerly, along Private . Way "A" into an existing storm drain inlet, ultimately discharging into the adjacent La Costa Greens Golf Course. Based on County of San Diego 2003 criteria, a runoff coefficient of 0.57 was assumed for the proposed multi-family residential development. Table 1 below summarizes the developed conditions: Table 1 -Summary of the Developed Condition Peak Flows Discharge Location Drainage Area (Ac) 100 Year Developed Peak Discharge'(cfs) Southern Outlet (Basin) 5.3 16.6 Northern Discharge 0.8 2.7 1.4 -Summary of Results Existing condition peak flowrates were obtained from the "Drainage Stu.dy for La Costa. Greens Neighborhoods 1.2 & 1.3 Developer Improvements" prepared by Hunsaker & Associates and dated August 2006. The hydrologic analysis prepared for the proposed La Costa Greens Neighborhood 1.3 project site in this study uses the City of Carlsbad methodology concurrent with the 2003 San Diego County Hydrology Manual methodology. For the developed condition rational method analysis, a runoff coefficient of 0.57 was used for the future single family residential area, corresponding to 7.3 DUlAc. Per the Mass-Graded Hydrology Study for La Costa Greens Neighborhoods 1.1-1.3 & EI Camino Real Widening, a runoff coefficient of 0.87 was assumed for the Neighborhood 1.3 development. With this coefficient, a flow of 20.08 cfs was calculated at the southern outlet location. Therefore, there is a slight decrease of about 3.5 cfs in the peak discharge at the southern outlet. The northern discharge is so minimal that the existing inlets will not be affected by the additional flow. Any slight increases will be easily mitigated by the existing Alicante detention basin. For more information on the Alicante detention basin, refer to the "Letter of Map Revision for La Costa Greens" prepared by Hunsaker and Associates. RE'kc H:IREPORTSI2301l15IDEV COND HYDRO-03,doc w.o. 2~01.15 8/5/2006 1 02-PM I I I I I I I I I I I I I I I I Developed Condition Drainage Study La Costa Greens 1.3 Best Management Practices (BMPs) have been recommended for this project site per the "Storm Water Management Plan (SWMP) for La Costa Greens Neighborhood 1.3 Developer' prepared by Hunsaker & Associates and dated July 2008. Four FloGard curb inlet filter units (or approved e~uivalent) and one extended detention basin have been recommended to treat the 85t percentile flow. An existing CDS treatment unit located north of the site on Private Way 'A' has been sized to accommodate runoff from the northern end of the La Costa Greens 1.3 development. RE kc H:IREPORTSI2301115IDEV COND HYDRO-03.dOC w.o.2301-15 6/5/20061'02 PM I I I I I I I . 1 I I I I I I I I II I I Developed Condition Drainage Study La Costa Greens 1.3 1.5 -References "San Diego County Hydrology Manual"; Department of Public Works -Flood Control Division; County of San Diego, California; Revised June 2003. "City of San Diego Regional Standard Drawings"; Section D -Drainage Systems; Updated March 2000. "City of Carlsbad Engineering Standards'.'; City of Carlsbad, California; June 2004. "Drainage Study for La Costa Greens Neighborhoods 1.2 & 1.3 Developer Improvements"; Hunsaker & Associates San Oiego, Inc.; August 2006. "Storm Water Management Plan (SWMP) for Developer Improvements La Costa Greens Neighborhood 1.2 & 1.3"; Hunsaker & Associates San Diego, Inc.; June, 2005 . "Master Detention Study for La Costa Greens"; Hunsaker & Associates San Diego, Inc.; August 2003. . "Mass-Graded Hydrology Study for La Costa Greens Neighborhoods 1.1-1.3 & EI· Camino Real Widening"; Hunsaker & Associates San Diego, Inc.; August 23, 2005. "Tentative Map Storm Water Management Plan (SWMP) for La Costa Greens Neighborhood 1.3"; Hunsaker & Associates San Diego, Inc.; April 13, 2005. RE:kc H IREPORTS\2301115IOEV qOND HYDRO·03 doc W 0 2301·15 8/5120081:02 PM I I I II I I- I I I I I I I I I I I II 'I I" I I I I I I I I I I I I I I· I I I I II Developed Condition Drainage Study La Costa Greens 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPM·ENT 2.1 -City of Carlsbad Engineering Stand·ards MJ p H.IREPORTS\23011151DEV COND HYDRO-Ol.doc w.o. 2301-19 41412008 3:22 PM I I I I I I I I I I ·1 I I I I I I I I CHAPTER 5-DRAINAGE AND STORM DRA1N STANDARDS 1. GENERAL A All drainage design and requirements shall be in accordance with the latest City of Carlsbad Standard Urban Storm Water Mitigation Plan (SUSMP), Jurisdictional Urban Runoff Management Plan (JURMP), Master Drainage and Storm Water Quality Management Plan and the requirements of the City Engineer and be based on full development of upstream tributary basins. B. Public drainage facilities shall be designed to carry the ten-year six-hour storm underground and the 100-year six-hour storm between the top of curbs. All culverts shall be designed to accommodate a 1 ~O-year six-hoblr storm with a one foot freeboard at entry conditions such as inlets and head walls. C. The use of underground storm drain systems, in addition to standard curb and gutter shall be required: 1) When flooding or street overflow during iDa-year six-hour storm cannot be maintained between the top of curbs. 2) When i0a-year six-hour storm flow from future upstream development (as proposed in the existing General Plan) will cause damage to structures and improvements. 3) When existing adequate drainage facilities are available for use (adjacent to proposed development). 4) When more than one travel lane of arterial and collector streets would be obstructed by 10-year 6-hour storm water flow. Special consideration will be required for super-elevated streets. D. The use of underground storm drain systems may be required: 1) When the water level in streets at the design storm is within 1" of top of curb. 2) When velocity of water in streets exceeds 11 FPS. 3) When the water travels on surface street improvements for more than 1,000'. E. The type of drainage facility shall be selected on the basis of physical and cultural adaptability to the proposed land'use. Open channels may be considered hi lieu of underground systems when the peak flow exceeds the capacity of a 48" diameter Rep. Fencing of open channels may be required as determined by the City Engineer. F. Permanent drainage facilities and right-of-way, including access, shall be provided from development to point of approved disposal. Page 1 of 5 I I I I I I I I I I I I I I I I I I I G Storm Drains constructed at a depth of 15' or greater measured from finish grade to the top of pipe or structure shall be considered deep storm drCjins and should be avoided if at all possible. When required, special design consideration will be required to the satisfaction of the City Engineer. Factors considered in the design will include: 1) Oversized specially designed access holes/air shafts 2) Line encasements 3) Oversizing lines 4) Increased easement requirements for maintenance access 5) Water-tight joints 6) Additional thickness of storm drain The project designer should meet with the planchecker prior to initiation of design to review design parameters. H. Concentrated drainage from lots or areas greater than 0.5 acres shall not be discharged to City streets unless specifically approved by the City Engineer. l. Diversion of drainage from natural or existing basins is discouraged. J. Drainage design shall comply with the City's Jurisdictional Urban Runoff Management Plan (JURMP) and requirements of the National Pollutant Oischarge Elimination System (NPDES) permit. 2. HYDROLOGY A Off site, use a copy of the latest edition City 400-scale topographic mapping. Show existing culverts, cross-gutters and drainage courses based on field review. Indicate the direction of flow; clearly delineate each drainage basin showing the area and discharge and the point of concentration. B. On site, use the grading plan. If grading is not proposed, then use a 100-scale plan or greater enlargement. Show all proposed and existing drainage facilities and drainage courses. Indicate the direction of flow. Clearly delineate each drainage basin showing the area and discharge and the point of concentration. C. Use the charts in the San Diego County Hydrology Manual for finding the "Te" and "I". For small areas, a five minute "Te" may be utilized with prior approval of the City Engineer. D. Use the existing or ultimate development, whichever gives the highest "C" factor. E. Use the rational formula Q = CIA for watersheds less than 0.5 square mile unles$ an alternate method is approved by the City Engineer. For watersheds rn excess of 0.5 square mile, the method of analysis shall be approved by the City Engineer prior to submitting calculations. Page 20f 5 I I I I I I I I I I I I I I I I I I I 3. HYDRAULICS A Street -provide: 1) Depth of gutter flow calculation. 2) Inlet calculations. 3) Show gutter flow Q, inlet Q, and bypass Q on a plan of the street. B. Storm Drain Pipes and Open Channels -provide: 1) Hydraulic loss calculations for: entrance, friction, junction, acCEiSs holes, bends, angles, reduction and enlargement. 2) Analyze existing conditions upstream and downstream from proposed system, to be determined by the City Engineer on a case-by-case basis. 3) Calculate critical depth and normal depth for open channel flow conditions. 4) Design for non-silting velocity of 2 FPS in a two-year frequency storm unless otherwise approved by the City Engineer. 5) All pipes and outlets shall show HGL, velocity and Q value(s) for. des;ign storm. 6) Confluence angles shall be maintained between 45° and 90° from the main upstream flow. Flows shall not oppose main line flows. 4. INLETS A Curb inlets at a sump condition should be designated for two CFS per lineal foot of opening when headwater may rise to the top of curb. . B. Curb inlets on a continuous grade should be designed based on the following equation: Q = 0.7 L (a + y)3/2 Where: y = depth of flow in approach gutter in feet a = depth of depression of flow line at inlet in feet L = length of clear opening in feet (maximum 30 feet) Q = flow in CFS, use 1 ~O-year design stonn minimum C. Grated inlets should be avoided. When-recessary, the design should be based on the Bureau of Public Roads Nomographs (now known as the Federal. Highway Administration). All grated inlets shall be bicycle proof. D. All catch basins shall have an access hole in the top unless access through the grate section satisfactory to the City Engineer is provided. Page 3 of 5 I 1.- I I I I I I I I I I I I I I I I I 5. E. F. Catch basins/curb inlets shall be located so as to eliminate, whenever possible, cross gutters. Catch basins/curb inlets shall not be located within 5' of any curb retum or driveway. Mnimum connector pipe for public drainage systems shall be 18". G Flow through inlets may be used when pipe size is 24" or less and open channel flow characteristics exist. STORM DRAINS A Minimum pipe slope shall be .005 (.5%) unless otherwise approved by the City Engineer. B. C. D. E. F. G H. Minimum storm drain, within public right-of-way, size shall be is'' diameter. Provide cleanouts at 300' maximum spacing, at angle points and at breaks in grade greater than 1 %. For pipes 48" in diameter and larger, a maximum spacing of 500' may be used. When the storm drain clean-out Type A dimension of 'V' less "Z" is greater than 18", a storm drain clean-out Type B shall be used. The material for storm drains shall be reinforced concrete pipe deSigned in conformance with San Diego County Flood Control District's design criteria, as modified by Carlsbad Standard Specifications. Corrugated steel pipe shall not be used. Plastic/rubber collars shall be prohibited. Horizontal curve design shall conform to manufacturer recommended specifications. Vertical curves require prior approval from the City Engineer. The pipe invert elevations, slope, pipe profile line and hydraulic grade line for design flows shall be delineated on the mylar of the improvement plans. Any utilities crossing the storm drain shall also be delineated. The strength classification of any pipe shall be shown on the plans. Minimum D-Ioad for RCP shall be 1350 in aU City streets or future rights-at-way. Minimum D-Ioad for depths less than 2'" if allowed, shall be 2000 or greater. For all drainage designs not covered in these Standards, the current San Diego County Hydrology and Design and Procedure Manuals shali be used. For storm drain discharging into unprotected or natural channel, propet energy dissipation measures shall be installed to prevent damage to the channel or erosion. In cases of limited access or outlet velocities greater than 18· fps, a concrete energy dissipater per SDRS D-41 will be required. Page 4 of 5 I I I I I I I I I I I I I I I I I I I I. J. K. L. M. N, o. P. The use of detention basins to even out storm peaks and reduce piping is permitted with substantiating engineering calculation and proper maintenance agreements. Detention basins shall be fenced. Desiltation measures for silt caused by development shall be provided and cleaned regularly during the rainy season (October 1 to April 30) and after major rainfall as required by the City Engineer or his designated representative .. Adequate storage capacity as determined by the City Engineer shall be maintained at all times. Protection of downstream or adjacent properties from incremental flows (caused by change from an undeveloped to a developed site) shall be provided. Such flows shall not be concentrated and directed across unprotected adjacent properties unless an easement and storm drains or channels to contain flows are provided. Unprotected downstream channels shall have erosipn and grade control structures installed to prevent degradation, erosion, alteration or downcutting of the channel banks. Storm drain pipes designed for flow meeting or exceeding 20 feet per second will require additional cover over invert reinforcing steel as approved by the City Engineer. Storm drain pipe under pressure flow for the design storm, i.e., HGL above the soffit of the ppe, shall meet the requirements of ASTM C76, C361 , C443 for water-tight joints in the sections of pipe calculated to be under pressure and an additional safety length beyond the pressure flow point. Such safety length shall be determined to the satisfaction of the City Engineer taking into consideration such·factors as pipe diameter, Q, and velocity. An all weather access road from a paved public right-of-way shall be constructed to all drainage and utility improvements. The following design parameters are required: Maximum grade 14%, 15 MPH speed, gated entry, minimum paved width 12 feet, 38' minimum radius, paving shall be a minimum of 4" AC over 4" Class II AB, tumaround required if over 300', Work areas sho)Jld be provided as approved by the plan checker. Access roads should be shown on the tentative project approval to ensure adequate environmental review. Engineers are encouraged to gravity drain all lots to the street without use of a yard drain system. On projects with new street improvements proposed; a curb outlet per SDRSD 0-27 shall be provided for single-family resjdentiallots to allow yard drains to connect to the streets gutter. Page 5 of 5 I I I I I I I I I I I I I I I I I I I CHAPTER 2 CITY OF CARLSBAD MODIFICATIONS TO THE SAN DIEGO REGIONAL STANDARD DRAWINGS Note: The minimum alfowable concrete mix design for all concrete placed within public right- of-way shall be 560-C-3250 as specified in the Standard Specifications for Public Works Construction. DWG. MODIFICATION 0-2 Enlarge curb inlet top to width of sidewalk (not to exceed 5'6") by length of inlet including wings. Existing reinforcing steel shall be extended across enlarged top to clear distances shown. 0-20 Delete. 0-27 Add: A maximum of three (3) combined outlets in lieu of Std. 0-25. 0-40 Add: "T" dimension shall be a minimum of three (3) times size of rip rap. 0-70 Minimum bottom width shall be 6' to facilitate cleaning. 0-71 Minimum bottom width shall be 6' to facilitate cleaning. 0-75 Delete "Type-A" Add: 6" x 6" x #10 x #1 0 welded wire mesh, instead of stucco netting. E-1 Delete direct burial foundation. Add: The light standard shall be pre-stressed concrete round pole. E-2 Grounding per note 2. Attachment of the grounding wire to the anchor bolt shall be below the light standard base plate with an approved connection. G-3 Delete. G-5 Add: Note 4. Tack coat shall be applied between dike and existing asphalt concrete surface as specified in Section 302-5.4 SSPWC. G-6 Type B-1 not used. When specified, Type B-2 shall have a curb height ofS",'f.{idth of 6", with a 3:1 batter. When specifically approved by the City Engineer, Type 8~3 shall have a curb height of 8", width of 6", a 3: 1 batter with the hinge point eliminated .. G-11 Add: Remove curb/gutter and sidewalk from score-mark to score-mark' or from joint-to-joint or approved combination. 1 I I I I I I ,I I I I I I I I I I I I I DWG. G-12 G-13 G-14 G-15 G-24 G-25 G-26 G-33 G-34 G-35 M M-2 CITY OF CARLSBAD MODIFICATIONS TO THE SAN DIEGO REGIONALSTANDARD DRAWINGS MODIFICATION Add: smooth trowel flow line (typical) 7-1/2" thick with a minimum of 6" of aggregate base per City of Carlsbad Standard GS-17. Add: smooth trowel flow line (typical), 7-1/2" thick, with a minimum 6" of aggregate base per City of Carlsbad Standard GS-17. Change: Residential Thickness = 5-112" Commercial/Multi-Family Residential Thickness = 7-1/2" Delete requirement 3 ''Type-A" only (delete "Type B") ''Type-C'' only (delete "Type 0") Change thickness from 5-1/2" to 7-1/2" and add minimum 4" Class II base under curb/gutter (to 6" past back of curb). Delete "Type-C" only (delete ''Type D") ''Type-F' only (delete "Type E") General: Agency shall be "City of Carlsbad II Add: To be used only with specific approval of the City Engineer. 2 I I I I I I I I I I I I I I I I I I I Developed Condition Drainage Study La Costa Greens 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPM'ENT 2.2 -County of San Diego Drainage Design Criteria MJ:p H.IREPORTS\230l1l51OEV COND HYDRO·Ol.doc w.o. 2301-15 4/4/2008 3 22 PM I I I I I I I I I I I I I I I I I I I San Diego County Hydrology Manual Date: June 2003 Section: Page: 2.3 SELECTION OF HYDROLOGIC METHOD .-\.i"iD DESIGN CRITERM :2 30f4 Design Frequency -The flood frequency for detennining the design storm discharge is 50 years for drainage that is upstream of any major roadway and 100 years frequency for all design storms at a major roadway, crossing the major roadway and thereafter. The 50-year storm flows shall be contained within the pipe and not encroach into the travel lane. For the 100-year storm this includes allowing one lane of a four-lane road (four 9r more lanes) to be used for conveyance without encroaching onto private property outside the dedicated street right-of-way. Natural channels that remain natural within private property are excluded from the right-of-way guideline. Design Method -The choice of method to determine flows (discharge) shall be based on the size of the watershed area. For an area 0 to approximately 1 square mile the Rational Method or the Modified Rational Method shall be used. For watershed areas larger than 1 square mile the NRCS hydrologic method shall be used. Please check with the governing agency for any variations to these guidelines. 2-3 I I I I I I I I I I I I I I I I San Diego County Hydrology Manual Date: June 2003 SECTION 3 Section: Page: RATIONAL lVIETHOD AL~D MODIFIED RATIONAL IvIETHOD 3.1 THER.\TIONALMETHOD 3 10f26 The Rational Method (RM) is a mathematical fonnula used to detennine the ma.'(imum runoff rate from a given rainfall. It has particular' application in urban stonn drainage, where it is used to estimate peak runoff rates from small urban and rural watersheds for the design of stonn drains and small drainage structures. The RM is recommended for analyzing the runoff response from drainage areas up to approximately I square mile in size. It should not be used in instances where there is a junction of independent drainage systems or for drainage areas greater than approximately 1 square mile in size. In these insta~qes, the Modified Rational Method (IvlRM) should be used for junctions of independent drainage systems in watersheds up to approximately 1 square mile in size (see Section 3.4); or the NRCS Hydrologic Method should be used for watersheds greater than approximately 1 square mile in size (see Section 4). The RM can be applied using any design stann frequency (e.g., I ~O-year, 50-year, 10-year, etc.). The local agency detennines the design storm frequency that must be used based.on the type of project and specific local requirements. A discussion of design storm frequency is provided in Section 2.3 of this manual. A procedure has been developed that converts the 6-hour and 24-hour precipitation isopluvial map data to an Intensity-Duration curve that can be used for the rainfall intensity in the Rl\1 formula as shown in Figure 3-1. The RM is applicable to a 6-hour storm duration because the procedure uses Intensity-Duration Design Charts that are based on a 6-hour storm duration. 3.1.1 Rational Method Formula The R.M formula estimates the peak rate of runoff at any location in a \vatershed as a function of the drainage area (A), runoff coefficient (C), and rainfall intensity (I) for a duratiori equal to the time of concentration (Tc) , which is the time required for water to 3-1 I I I I I I I I I I I I I I I I I I I San Diego County Hydrology Manual Date: June 2003 Section: Page: 3 30f26 flow from the most remote point of the basin to the location being analyzed. The RM formula is expressed as follows: Where: Q=CIA Q = peak discharge, in cubic feet per second (cfs) C runoff coefficient, proportion of the rainfall that runs off the surface (no units) = average rainfall intensity for a duration equal to the Te for the area, in inches per hour (Note: Ifthe computed Te is less than 5 minutes, use 5 minutes for computing the peak discharge, Q) A = drainage area contributing to the design location, in acres Combining the units for the expression CIA yields: (1 acre x inch) (43,560ft2) ( 1 foot ) ( 1 hour ) => l.OD8cfs hour acre 12 inches 3,600 seconds For practical purposes the unit conversion coefficient difference of 0.8% can be ignored. The R.M formula is based on the assumption that for constant rainfall intensity, the-peak discharge rate at a point will occur when the raindrop that falls at the most upstream poiilt in the tributary drainage basin arrives at the point of interest. Unlike the MRM (discuss.ed in Section 3.4) or the NRCS hydrologic method (discussed in Section 4), the RlvI does not create hydrographs and therefore does not add separate subarea hydrographs at collection points. Instead, the R.M develops 'peak discharges in the main line by increasing the Te as flmv travels downstream. Characteristics of, or assumptions inherent to, the RM are listed below: Q The discharge flow rate resulting from any 1 is maximum when the I lasts as long as or longer than the Te. 3-3 I I I I I I I I I I I I I I I I I I I San Diego County Hydrology Manual Date: June 2003 Section: Page: I) The storm frequency of peak discharges is the same as that ofl for the given Te. 3 4of26 '0' The fraction of rainfall that becomes runoff (or the runoff coefficient, C) is independent of I or precipitation zone number (PZN) condition (PZN Condition is .discussed in Section 4.1.2.4). e The peak rate of runoff is the only information produced by using the RM. 3.1.2 Runoff Coefficient Table 3-1 lists the estimated runoff coefficients for urban areas. The concepts related to the runoff coefficient \vere evaluated in a report entitled Evaluation, Rational lHethod "e" Values (Hill, 2002) that was reviewed by the Hydrology Manual Committee. The R.eport is available at San Diego County Department of Public Works, Flood Control Section and on the San Diego County Department of Public Works web page. The runoff coefficients are based on land use and soil type. Soil type can be determined from the soil type map provided in Appendix A. An appropriate runoff coefficient (C) for each type of land use in the subarea should be selected from this t~ble and multiplied by the percentage of the total area (A) included in that class. The sum of the products for all land uses is the weighted runoff coefficient (1:[CAJ). Good engineering judgment should be used when applying the values presented in Table 3-1, as adjustments to these values may be appropriate based on site-specific characteristics. In any event, the impervious percentage (% Impervious) as given in the table, for any area, shall govern the selected value for C. The runoff coefficient can also be calculated for an area based on soil type and impervious percentage using the following formula: 3-4 I I I I I I I I I I I I I I I I I I I San Diego County Hydrology Manual Section: Date: June 2003 Page: 3 50f26 Where: C = 0.90 x (% Impervious) + Cp x (1 -% Impervious) Cp = Pervious Coefficient Runoff Value for the soil type (shown in Table 3-1 as Undisturbed Natural TerrainlPermanent Open Space, 0% Impervious). Soil type can be determined from the soil type map provided in Appendix A. The values in Table 3-1 are typical for most urban areas. However, if the basin contains rural or agricultural land use, parks, golf courses, or other types of nonurban land use that are expected to be permanent, the appropriate value should be selected based upon the soil and cover and approved by the local agency. 3-5 I I I I I I I I I I I I I I I I San Diego County Hydrology Manual Date: June 2003 3.1.3 Rainfall Intensity Section: Page: 3 7of26 The rainfall intensity (I) is the rainfall in inches per hour (in/hr) for a duration equal to the Tc for a selected stonn frequency. Once a particular stonn frequency has been selected for design and a Tc calculated for the drainage area: the rainfall intensity can be determined from the Intensity-Duration Design Chart (Figure 3-1). The 6-hour stonn rainfall amount (P6) 'and the 24-hour stonn rainfall amount (P14) for the selected storm frequency are also needed for calculation of 1. P6 and P2-l can be read from the isopluvial maps provided in Appendix B. An Intensity-Duration Design Chart applicable to all areas within San Diego County is provided as Figure 3-1. Figure 3-2 provides an example of use of the Intensity-Duration Design Chart. Intensity can also be calculated using the following equation: 1= 7.44 P6 D-o,645 Where: P6 = adjusted 6-hour stonn rainfall amount (see discussion below) D duration in minutes (use Tc) Note: This equation applies only to the 6-hour storm rainfall amount (Le.: P6 cannot ,be changed to P1-l to calculate a 24-hour intensity using this equation). The Intensity-Duration Design Chart and the equation are for the 6-hour storm rainfall amount. In general, P6 for the selected frequency should be between 45% and 65% OfP24 for the selected frequency. If P6 is not within 45% to 65% of P24, P6 should be increased or decreased as necessary to meet this criteria. The isopluvial lines are based ,on precipitation gauge data. At the time that the isopluvial lines were created: the majority of precipitation gauges in San Diego County were read daily, and these readings yielded 24-hour precipitation data. Some 6-hour data were available from the few recording gauges distributed throughout the County at that time; however, some 6-hour data were extrapolated. Therefore, the 24-ho1.lr precipitation data for San Diego County are considered to be more \ reliable. 3-7 I I I I I I I I I I I I I I I I I I San Diego County Hydrology Manual Date: June 2003 3.1.4 Time of Concentration Section: Page: 3 9006 The Time of Concentration (Tc) is the time required for runoff to flow from the most remote· part of the drainage area to the point of interest. The Te is composed of two components: initial time of concentration (Ti) and travel time (TJ. Methods of computation for Ti and tt are discussed below. The Ti is the time required for runoff to travel across the surface of the most remote subarea in the study, or "initial subarea." Guidelines for designating the initial subarea are provided within the discussion of computation of Ti. The Tt is the time required for the runoff to flow in a watercourse (e.g., swale, channel, gutter, pipe) or series of watercourses from the initial subarea to the point of interest. For the RIvl, the Te at any point within the drainage area is given by: Methods of calculation differ for natural watersheds (nonurbanized) and for urban drainage systems. When analyzing storm drain systems, the designer must consider the possibility that an existing natural watershed may become urbanized during the useful life of the storm drain system. Future land uses must be used for Te and runoff calculations, and can be determined from the local Community General Plan. 3.1.4.1 Initial Time of Concentration The initial time of concentration is typically based on sheet flow at the upstream end of a drainage basin. The Overland Time of Flow (Figure 3-3) is approximated by an equation developed by the Federal Aviation Agency (FAA) for analyzing flo'w on runaways (FAA, 1970). The usual runway configuration consists of a crown, like most freeways, with sloping pavement that directs flow to either side of the runway. This type of flo",,\' is uniform in the direction perpendicular to the velocity and is very shallow. Since these depths are 14 of an \ inch (more or less) in magnitude, the relative roughness is high. Some higher relative roughness values for overland flow are presented in Table 3.5 of the HEC-J Flood Hydrograph Package User's Manual (USACE, 1990). 3-9 I I I I I I I I I I I I I I I I I I San Diego County Hydrology Manual Date: June 2003 Section: Page: 3 110f26 The sheet flow that is predicted by the FAA equation is limited to conditions that are similar to runway topography. Some considerations that limit the extent to which the FAA. equation applies are identified below: El Urban Areas -This "runway type" runoff includes: 1) Flat roofs, sloping at 1 % ± 2) Parking lots at the extreme upstream drainage basin boundary (at the "ridge" ora catchment area). Even a parking lot is limited in the amounts of sheet flow. Parked or moving vehicles would "break-up" the sheet flow, concentrating runoff into streams that are not characteristic of sheet flow. 3) Driveways are constructed at the upstream end of catchment areas in some. . developments. However, if flow from a roof is directed to a driveway through a downspout or other conveyance mechanism, flow would be concentrq.ted. 4) Flat slopes are prone to meandering flow that tends to be disrupted by minor irregularities and obstructions. Maximum Overland Flow lengths are shorter for the flatter slopes (see Table 3-2). El Rural or Natural Areas -The FAA equation is applicable to these conditions since (.5% to 10%) slopes that are uniform in width of flow have slow velocities consistent with the equation. Irregularities in terrain limit the length of application. 1) Most hills and ridge lines have a relatively flat area near the drainage divide. Ho\vever, with flat slopes of .5% ±, minor irregularities would cause flow to concentrate into streams. 2) Parks, lawns and other vegetated areas would have slow velocities that are consistent with the FAA Equation. The concepts related to the initial time of concentration were evaluated in a report entitled Initial Time of Concentration, Analysis of Parameters (Hill, 2002) that \vas reviewed by the \ Hydrology Manual Committee. The Report is available at San Diego County Department of Public Works, Flood Control Section and on the San Diego County Department of Public Works web page. 3-11 I I I I I I I I I I I I I I I I I I I San Diego County Hydrology lvlanual Date: June 2003 Section: Page: 3 120f26 Note that the Initial Time of Concentration should be reflective of the general land-use at the upstream end of a drainage basin. A single lot with an area of two or less acres does not have a significant effect where the drainage basin area is 20 to 600 acres. Table 3-2 provides limits of the length (Maximum Length (Lt;.!)) of sheet flow to be used in hydrology studies. Initial Ti values based on average C values for the Land Use Element are also included. These values can be used in planning and design applications as described below. Exceptions may be approved by the "Regulating Agency" when submitted with a detailed study. MAXIMUM OVERLAND FLOW LENGTH (LM) & INITIAL TIME OF CONCENTRATION (Ti)' Element* DUI .5% I 1% I 2% 3% I' 5% I 10% Acre LM I Ti I LM I Ti I LM I Ti LM I Ti I LM I Ti I Ll\'! I Ti Natural I I 50 113.21 70 112.51 85 10.9 100 110.3 100 I 8.71100, .6.9 LDR 11 50 112.21 70 111.5 i 85 10.0 100 I 9.51100 I 8.0, 100 6.4 LDR 12 I 50 111.31 70 110.5! 851 9.211001 8.81100 I 7.41100 5.8 LDR I 2.9 I 50 110.71 70 110.0 I 8s1 8.8 I 951 8.1 1100 1'7.0 1100 I 5.6 NIDR 14.3 SO 110.2 I 70 I 9.61 80 I 8.1 I 951 7.8 1001 6.7 100 I 5.3 MDR 17.3 I 50 I 9.21 651 8.41 80 I 7.41 951 7.0 1100 I 6.0 100 4.8 MDR 110.9 I SO I 8.7/ 65 7.91 80 I 6.9 90 I 6.4 100 I 5.1' 1100 4.5 MDR 114.5 I 50 I 8.21 65 7.41 80 I . 6.51 90 I 6.0 1.100 I S.411001 4.3 HDR 124 I 50 1 6.7 1 65 6.1-' 75 5.1 . 90 I 4.9 9514.3 10Q I 3.5 HDR 143 50 I 5.31 651 4.il 751 4.0 I 851 3.81. 9513.4 100 I 2.7 N.Com I 50 I 5.3 I 60 I 4.5 I 7S I 4.0 851 3.81 951 3.411001 2.7 G.Com I I 50 I 4.71 60 4.1 I 751 3.6 I 851 3.41 90·1 2.91100 I 2.4 O.P.lCom I 1 501 4.21 60 1 3.71 70 1 3.1 I 80 1 2.9 90 f 2.61100 1.2.2 Limited 1.1 I 50 I 4.2 I 60 I 3.71 70 I 3.1 I 80 I 2.9 90 I 2.6 1100 I 2.2 General 1. I 50 I 3.7 I 60 I 3.21 70 I 2.7 80 I 2.61 90 1 2.3, ·1100 1.9 *See Table 3-1 for more detailed description 3-12 I I I I I I I I I I I I I I I I I I I San Diego County Hydrology lv!anual Date: June 2003 3.1.4.1A Planning Considerations Section: Page: 3 130f26 The purpose of most hydrology studies is to develop flood flow values for areas that are not at the upstream end of the basin. Another example is the Master Plan,. which is usually completed before the actual detailed design of lots, streets, etc. are accomplished. In these situations it is necessary that the initial time of concentration be determined without detailed information about flow patterns. To provide guidance for the initial time of concentration design parameters, Table 3-2 includes the Land Use Elements and other variables related to the Time of Concentration. The table development included a review of the typical "layout" of the different Land Use Elements and related flow patterns and consideration ofthe extent of the sheet flow regimen, the effect of ponding, the significance to the drainage basin, downstream effects, etc. 3.1.4.1B Computation Criteria (a) Developed Drainag:e Areas With Overland Flow -Ti may be obtained directly from the chart, "Rational Formula -Overland Time of Flow Nomograph," shown in Figure J-3 or from Table 3-2. This chart is based on the Federal Aviation Agency (FAA) equation (FAA, 1970). For the short rain durations «15 minutes) involved, intensities are high but the depth of flooding is limited and much of the runoff is stored temporarily in the overland flow and in shallow ponded areas. In developed areas, overland flow is limited to lengths given in Table 3-2. Beyond these distances, flow tends to become concentrated into streets, gutters, swales, ditches, etc. 3-13 I I I I I I I I I I I I I I I I I I I San Diego County Hydrology Manual Date: June 2003 Section: Page: 3 14of26 (b) Natural Or Rural Watersheds -These areas usually have an initial subarea at the upstream end with sheet flow. The sheet flow length is limited to 50 to 100 feet as specified in Table 3-2. The Overland Time of Flow Nomograph, Figure 3-3, can be used to obtain Ti. The initial time of concentration can excessively affect the magnitude of flow further downstream in the drainage basin. For instance, variations in the initial time of concentration for an initial subarea of one acre can change the flow further downstream where the area is 400 acres by 100%. Therefore, the initial time of concentration is limited (see Table 3-2). The Rational Method procedure included in the original Hydrology Manual (1971) and Design and Procedure Manual (1968) included a 10 minute value to be added to the initial time of concentration developed through the Kirpich Formula (see Figure 3-4) for a natural watershed. That procedure is superceded by the procedure above to use Table 3-2 or Figure 3-3 to determine Ti for the appropriate sheet flow length of the initial subarea. The values for natural watersheds given in Table 3-2 vary from 13 to 7 minutes, depending on slope. If the total length of the initial subarea is greater than the ma'\:.imum length allowable based on Table 3-2, add the travel time based on the Kirpich formula for the remaining length of the initial subarea. 3.1.4.2 Travel Time The Tt is the ,time required for the runoff to flow in a watercourse (e.g., swale, channel, gutter, pipe) or series of watercourses from the initial subarea to the point of interest. The Tt is computed by dividing the length of the flow path by the computed flow velocity. Since the velocity normally changes as a result of each change in flow rate or slope, such as at an inlet or grade break, the total Tt must be computed as the sum of the Tt's for each section of the flow path. Use Figure 3-6 to estimate time of travel for street gutter flow. Velocity in a channel can be estimated by using the nomograph shO\.vn in Figure 3-7 (Manning's Equation \ Nomograph). 3-14 I I I I I I I I I , I I I I I I I I I San Diego County Hydrology Manual Date: June 2003 Section: Page: 3 150f26 (a) Natural Watersheds -This includes rural, ranch, and agricultural areas \\lith natural channels. Obtain Tt directly from the Kirpich nomograph in Figure 3-4 or from the equation. This nomograph requires values for length and change in elevation along the effective slope line for the subarea. See Figure 3-5 for a representation of the effective slope line. This nomograph is based on the Kirpich formula, which was developed with data from agricultural watersheds ranging from 1.25 to 112 acres in area, 350. to 4,0.0.0. feet in length, and 2.7 to 8.8% slope (Kirpich, 1940.). A maximum length of 4,0.0.0. feet should be used for the subarea length. Typically, as the flow length increases, the depth of flow yvill increase, and therefore it is considered a concentration of flow at points beyond lengths listed in Figure 3-2. However, because the Kirpich formula has been shown to be applicable for watersheds up to 4,0.0.0. feet in length (Kirpich, 1940.), a subarea may be designated with a length up to 4,0.0.0. feet provided the topography and slope of the natural channel are generally uniform. Justification needs to be included with this calculation showing that the watershed will remain natural forever. Examples include areas located in the Multiple Species Conservation Plan (MSCP), areas designated as open space or rural in a community's General Plan, and Cleveland National Forest. (b) Urban Watersheds -Flow through a closed conduit yvhere no additional flow can enter the system during the travel, length, velocity and Tt are determined using the peak flow in the conduit. In cases where the conduit is not closed and additional flow ftom a contributing subarea is added to the total flow during travel (e.g., street flow in a gutter), calculation of velocity and Tt is performed using an assumed aver:age flow based on the total area (including upstream subareas) contributing to the point of interest. The Manning equation is usually used to detem1ine velocity. Discharges for small watersheds typically range from 2 to 3 cfs per acre, depending on land use, \ drainage area, and slope and rainfall intensity. Note: The MRi\1 should be used to calculate the peak discharge when there is a junction from independent subareas into the drainage system. 3-15 I I I I I I I I I I I I I I I I I I II Developed Condition Drainage Study La Costa Greens 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPM:ENT 2.3 -Design Rainfall Determination 100-Year, 6-Hour Rainfaliisopiuvial Map MJ:p H.IREPORTS\2301l151DEV eOND HYDRO'Ol.doc. w.o. 2301-15 41412006 S·22 I'M ---- -- ----- ---- -- -- . I . :',: ~;;ni~ ~~.~:~ ~ .•. ?1i!{r:~T'~~~·'J~DY;! ~'~~:j" . '~~~-: : !t~ilC~,_' ___ _ 33'30 COUI1ty!., (" ,&:. ':'.:".,;:, . _ ".". i 33'30' .... - ) .i/ -:"'., R~~:::~~:~r~::~~«::i~:"'C:' 'C·c.' .•.• :z:,,~:<::\ -i 'l.; J\~ i~: ·.V;;!:':~:·!:::··:·~;;i:~·>~:~ \.\:;. · .. ·;k:· .... ~.· .. . o· . : . "l~/ .... :, ...... ,....",,"; .. : .. :::/ . ..1: ::""':~~l'~~: . :~; ·:.i:~ ~ >~:.:( .. ) .. ···!~~:~:l·l.·i (1 ,~: .... :J~r::~~.) \. ~.>. \\ \ ... \f \ .... , .... \.. :". ·:::::· ............ ~ .. ~~~15 • 33'15'-----"":\7 ,I ";r"':;;~ ...... !.} I ... .~.-,/, "'-.; ............ : :..." ./ .. \ 2.£ . '. J~~-8i;£lf,~~"o;""'~: .. C . .:' .;.~l •. ~'::;:;'>0 ~.\»~:r., .. __ ""''' . I oc .. ,\-l .... ~c::~~{.:j •. , .... " ". I j~ .. j:""" •••• • ... -..... . ~ .... ". '.', ......... .f ••••• .; ...... 4. ~.".""'-~ :\)~;.;..~ .. ;-. . ,,: .... :$~ ~·)~;%~·:~~~~~~:~t -... ?t'S'" ; ... ·:·:...··X····. \~:.~. \ .. ~ /-..<:.-:::.: .. ~ ................... "'~~::: . "b \'fG I"() ,,~ARLS~AO ,,~~!; ,,);.~: ':/':~i~i:':r:-::;I~:';;~:'::C: 1 /::' (?~~;/\i.:~\;~\:.~:::i>.c.~(~.:\"···· .. ';';:e· .••....... ""' ... ; .i ...... : . - . ·1·' ~\J," \k~y.:l._~;.jiF!i{':>r~ " ·"'"12-::)~.\ : ... :~' ... / .. /. .... :.\:\,.... l':» .. ). . .: ~ .. : (, .Nc""rASi~·· <,.;; ...................... ~('. ...../-..... I. . .... os: .• -!-.......... r~-' .. 33"00" 'I ... .:,:.. -... \$~::' 1" ., /.~ :,,'H.:' ·";I.:~"~~:. "~:.:{::::.."-/ " . "'. 'j!':'" ·r.:·Q-jI,·· .. ;'1 t\ •• _,1----. :...... ' .... ..£.' ~;.;!.f.!-,'~ ,-;/-1-.-.., . : :s.o:COUNlY ... ,\i:" . '.. ..•. .. .. "-0, ..... =., ......... :.. , ;:,' 33'00' -----;-, ---':n"--;·;;;·O~LA:;;NA;;;;DEACfl '111" .'. :,. 'POWAY. 1.'.:", • . .. r. • .. ,::::.. 1. ' ...... , . .' ,_. ..'.,..... ,,'=!I ' " .. ·1. __ ..... ,. ~ •• ''''_'\,' • ~" .: .... '~_"" ...... •• . '-' '0. . ... ":0,;; ~j,;r\t~ r.-. (ll \. \ \/ ''';,. }:3~~,.,\/") . ", \ /""';' ~ 0 • .,' .l¥i'i.(:,,\r~~.~t')\:i~~/.J.;;~~\\:<~::;~~ .. ~ ::Z:};\\ r\/"'7 ~. ';~1ir~·'~:~~~<j\~~~ .. ')J\)\\'~\"']I·/~:':: ,_. .. . -r!..~, --;-; ,~~b -·1¥;1:" :' ;1:...; ... " .. ",--,: ,"'" o;:::---'~: ....... -:;...... \... . . 32'45' ----r-------:l ,,'~ ·"'r" liei. '. ii' ~ .. , '~-__ ." .... :1.. ....... '" _""\::~.;.. ' . . -:::.·.Yfo~~r".'~,.;: .. ~y~~"~ '~<~~'-{' .. .'. / ~/f~ ... \.~ -:· .. ·?~1·.~· .. :·-':":':. .. ; .. ~ .... s~~~. "L'o : .......... . ' ,(~<\;:!~,; .L.~I·'. ; . .:j"... 'i:u : I.: ......... ,..'J,;.". • .. -:, ....... \-.•.•. <l> • '. I ' (~9.!!.l1NfI~~ . .;::1 .• :}!' .... , '~: 'i"' .. ' , I:,""" ..... ,'" .. .~' ;, '~ .. , : f/ . . ::,:,;;;.......-.,. ',?l>' .... :( . C::'!i? v~. ~; ... ~ ..... ::.,~ •.•• ,!: ;'I~ ./ <?\\'f:'-'''''"~., ..... :·· .. ·."1. ! ..... ':":'?:. ,.,,;.;:::::1 '. '\\..:," ~i ~ -"; "·;·'Z':;--:.:~ ~ ••• ' . r: ... .: ..... :;', r:s" ,; ... '. J ~. " . : ..... : ........ ;r".. . \ ... ...-./"'''' "\ I .'::.:~. '..... ;.-f ...... 1f! .... ~. l..' .P;;' l"' .• !lI' ""''''''!' r--:-. .. . .'. , "-.,. . ..,.l;", .... " . . . ' = ~l~'~~;,~ :~.I.f~Jl~QJ··"·::·" .. "" ~~~?~:(:~{:~::::~F('"'' ..... ,,"; .. "-'-:."' ... '" .... IMPERIALDEAg) • ~:., '·'I-::"!t-!.}U,.. . .. / .. /. : : .. ~. ~ '\\' ',' i .. e :)( 'i 'C f' . ;._; ".'}~1i~:.::"'-:_1 "::.:. .. . . ., ::. .. ... . . i" . I.. . .:,' " I .. 32'30' ----. . ~ t:: ~ o. to '" ... in 0 '" "", !'" ~ '!g ... I' ~ ~ I: 32'30' COlmty of San Diego Hydrology Manual Rai1rfall Isopluvials 1 !)() Y cal' R:linf:l~1 Evclll-~ Hom's ~ Isoplullial (Inchos) L_. _____________ ..-! '1J 1/ !J~/6i-::' Z·6 I)p'Xl ·· .. ·~GIS ~T$- C ... ~.I',J.._..;\ ...... I "' .. .,.f.·' ... • .... "'rl';v.· • -\I(~< 0liPlltR '1\....J1' h...~. \-';:", Ho!~·.;:·II. n:-:,:ol\ ·".-I:'·!! N 1I.," ...... prll.,.I.,UI\'OltI~·lIlIYI~IT'DI'Nrtlt:i<D.[II"ltltl'l'l!l!" * r:.-'I'JI'U:I).\lCVJnJ.fU1UIMlllr.'l1l'IIUllli!\\IIlI~DVfAAIWl1It' Q .... tno.oun"ul1'1'.-:l1)tlTlll:urc:.n .. r.lJltQ.v.'1plW'OSI:. ec7f\;to:C/oI>:IIt.U.IIo)l.aIl", .. ot Th.",U;";I ... IY ...... _ .. « .... "l(O.Iof>" ... 'liAloO.lG""~ ... -4I \V E =!.~~.~":.i~:~.:t ... "p: ... I-.. ,...., ••• P .. S 1h.'J'I'*,.-, •• ,U>fol'III"""")I2I"-':~NoU"""t,~",,,,".J .. ;h 1.""· ..... ".-.t'~b,n._III ... '.~"'-'I .. 30 3 Miles ~ I I I I I I I I I I I I I I I I I Developed Condition Drainage Study La Costa Greens 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPM'ENT 2.3 -Design Rainfall Determination 100-Year, 24-Hour RainfalilsopluVial Map MJ'p H.IREPORTSI23011151DEV COND HYDRO·Ol.doc w.o 2301-154/4/20083:22 PM ---------.. -------- , L. __ . ----~L_=_-_.0_ o -.--~ ;;-- Ul ------=--~-... -rn-_____ l. __ _ .--.~-.---~.--=~:::---. -.-.---'-~ .. --"J-.. -:----.-~.----=:~:=:=-~ 0----.., -_ .. ------1-. ! . __ .... _._1 ... __ ... _2 _____ ._ '~,"" ::.~ .... :::..--ll~~:;!···,lxjf<~(~~~~~;;;:~:~.~.·\\~:;:~~-, .. ~ __ y:-::;:;:_kl:/~\~~:.: ... :i\.:;~,~::'i \>1 .. \,.u L::t-::::::::: .. -;~r ;~~;:-~"'~0-.-1-'\ -, -"," -.. t -i'"' '--,--,,' I---~ , < " '" ", I ,-, '" L-, ~" -I~~~~~~:;;~~::.~~~,~;~:~'~~l~~::~:=~~,~';'j": ---. .. .-~":---nt'lt~,!;.r :, ... ,,:,;1 I -LL:'fI .": .c_.q,_. -·\ .. ·.· .. ,·c·~ ::, I ........ :,f ..... , v ..... _.~_., •• _ •. -... . -'\>~r~T.; t-L~l~"~:;~i~;:;:K;~ '~;;2l\):\2;:;i~:::1'f~~~::::~' S11'b I ;--., -. \ -'tt:i\]"~ 'l';' :""'-1~;; -, ,\, -, /-... / ,-1";. ~ "';;-,..c:'O>,,: ---.--•• ;; \',... -, . ,;;-cf\U~;~~f*t';/~lb~::):~--~{~_~_~ __ ;::~~IJ!_ ;;,-._ 33'00' .S!.. SOIA"AUI!J\Ct\'\\r.:r"J";:.::~!-, t,.: ·r0!'id~ .. \ i :.'. ~~, .... . ..... .... .~ .1"; : r.: 'Ai'~" L.. ,..:.. ,m'P ... _. , " i I , ":-r'-; " ~-! ,;'I"' fi" .' .\(--.; '32'45' ------1 1 , '. ". ::~~':~ ~.~~::~~~{V.lt'7<.;.~~~~,~:~:::·,;::7·: "~2~~~·~·:::,-··,··;:·::~··>:···1~. "\~>"') \ r~. ,~~"'s.;t ·'>:~';.;t;!1.:j('.···· .... tID,." .. It; -r ,.qf5::..... " JiJfI~-.~~ ...... -~~~.. /.-.. ,... .. "-',"" I'" -.. '. S .. '\~{~i,.:~,(~;~~~:4i~:;;::-:/ ,:.:.'~._.;·\\\:::.:A !\.~/: .. ~ .. ~:::::': .• l~ I:~ ............ R?(.'-.~ '. l. ~()" ...•.. . '--. .{\c .: .. "~,, !: .:: .• ~.!\ ••• ,:: • .: • ",:j;:J:(t.'!t j..-: ,'. !1l: :.0 \ . ,.' ;;: . .-\\ .. " ...... ~~J">=.-\ -.. -.· ..... 1. -... ./ .!,\l~~~~~~;·~~i:~:~·:.~~./7( ,{' :; -t·:·;·)-':::~:-~f:X::~3;.';r-./ ........... '. \ ~i, .. ~(':.l~.",·,,: .;~t :.: .:~ ... :' .... -.... . .. !<S'" .~.5,--' .: r~.. ... .. ·r .. f. ., .......... . ... -... "".,...\.~. -.-.. ~ ·,~~.ER~:~~~~.~~l~~j~i.Mt~~ ... ;i;~~!~·/~~~~{~~=~:~::r&~~~r .. -... :< .. :~ .. ~~ .. :~_: -"' .~ ~ .. :' . ~ .. 1-• , 32'30' ... -I I I . . --32'30' ' ... 0 ... -ra b .. _ £0___ . Q._._ .. ~_ •• w._. to ~ ~ 0 ~ ~. ~ . ~: ..... --.-.-.: --.... S: -.--.~.-.... M •• _ .... _~ ~ ) •• __ • ~.. .,; "';'"._.......... .~_ ... ___ •••• ",,_. ___ ._ ••• _ County of San Diego Hydrology Manual Rainje"IIsopl1lvials 100 Yenl' Ruinfn!l E"cllt.=.~4 Houl's ---, IEopluvi.1 (Inches) ! ____ ._ .... _ .. _. _____ J t1) 1: II Tj~:V( ::; .J 0 0 DIP'\lV ~';:'~GIC' ~-V ~1.>'t"""1'1\.:.,c\1).\' , ... ,"I-,.· .... "" ... IJ ..... n ~~ .. \LJ,I.":a ('I -If (;' ';:,: f .1 .. jf.hk~ .~..:l·n ..... .-Ir: .):.~. t :.I.' .... ! N lJI<~ ~W'I!. rnDmtOlllllr.lU'f :If.fliVU.trt.t "MlUr.u ''''''II ~"I'III"" -+ UIIWUfblr.:II1!";1I nlll';f1Il",mrlJlt1t1~r.'J1.l!o\·'.vtlUIlfI£~ D' Vtlll:.l.lolnAlIlI"t 11..',10 IIIIJUUcn ... P,l.'\III:II1M ,uaHI~_ C1r.,~Ca"G.,.Un.JMIlI''''''! n.lI"N~WI,~I'duv .. ll"II"' .. r"'III11.u~UMlll1·d \V;; E ~:;::!'£:X~'d~~~:~"''''M'''I'I~''''N S '''·II·''f):t ... /U''' ........... ul~ .... w..uk .... It;'J;'u~u .. ,.,. '-"" ... ,·I'U'Jllt""'WIOtor:o.t.1,!131.. 30 3 Miles ~ - I I I I I I I I I I I I I I I I II I I Developed Condition Drainage Study La Costa Greens 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPM'ENT 2.4 -Rainfall Coefficient Determination MJ:p H.\REPORTS\230l\15\DEV COND HYDRO·Ol.doc 'W.O, 2301-15 4/4/2008 3,22 PM ----- Sun Diego County Hydrology Manuul Dute: June 2003 ----.. - - --- Section: Page: Tnblc 3-1 RUNOli'F COEFFICIENTS FOR URBAN AREAS Land Usc Runoff Coeflieient "c" Soil Type NRCS Elements Countl Elements %IMPER. A B Undisturbed Natural Terrain (Natlll'al) Permanent Open Space 0* 0.20 0.25 Low Density Residenti,,1 (LDR) Residential, 1.0 DUIA or less 10 0.27 0.32 Low Density Residential (LDR) Residential, 2.0 DUIA or less 20 0.34 0.38 Low Density Residential (LDR) Residential, 2.9 DUIA or less 25 0.38 (lAI Mediulll Density Residential (MDR) Residential, 4.3 DUIA or less 30 OAI 0.45 Medium Density Residenliul (MOR) Residential, 7.3 DUIA 01' less 40 0,48 0.51 Mediulll Density Residential (MDR) Residcnliul, 10.9 DUIA or less 45 0.52 0.54 Medium Density Residential (MOR) Residential, 14.5 DUll\. or less 50 0.55 0.58 High Density Residential (I-IDR) Residentiul, 24.0 DUIA or less 65 0.66 0.67 High Density Rcsiden1iul (I-IDR) Residcntiul, 43.0 DUIA or less 80 0.76 0.77 COll1ll1crcial/lndustriul (N. Com) Neighborhood COllllUel'eihl 80 0.76 0.77 COlllmercial/lndustrial (G. Com) Gencl'IIl.Colllmel'eial 85 o.no o.no Commercial/industrinl (O.P. Com) Omce Pl'ofessiunaflCollllJlercill1 90 0.83 0.84 COllllllcrciuflindustrinl (Limited I.) Limited industri;11 9() U.B3 0.84 Commerciulli ndustrilll (Generlll I.) Geneml industl'ial 95 0.87 0.87 - C 0.30 0.36 0.42 (lAS 0,48 0.54 (l.S7 0.60 0.69 0.78 0.78 0.111 O.B4 n.B4 n.R7 - 3 60f26 D 0.35 OAI 0.46 0.49 0.52 0.57 0.60 0.63 0.71 (l .. 79 0.79 0.82 0.85 O.IlS O.1l7 - *The values associaled with ()%. impervious may be used lor direct eal~ulation or the runoff cocflieicnl as described in Section 3_1.2 (representing lhe pervious runoff coefficient, Cp, lur the soil type), or lbr arcus that will rClllainundisturbed in perpetuity. Juslilicalion Illusl bc given lhat thc arca willrcmain (Hltuml forever (e.g., the nnm is loclltcdin Cleveland Nutional Forest). OUIA = dwelling units pCI' acre NRCS = National Resources Conservation Service 3~6 -- I I I I I I I 'I I I I I I 'I I I I !I I Developed Condition Drainage Study La Costa Greens 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPM'ENT 2.5 -Rainfall Intensity Determination Maximum Overland Flow Length & Initial Time of Concentration Table MJ.p H.\REPORTS12301\15\DEV eOND HYDRO.01.doc w.o. 2301·15 4/4/2008 3'22 PM I I I I I I I I I I I I I I I I ; I I I San Diego County Hydrology Manual Date: June 2003 Section: Page: .., ,j 120f26 Note that the Initial Time of Concentration should be reflective of the general land-use at the upstream end of a drainage basin. A single lot with an area of two or less acres does not have a significant effect where the drainage basin area is 20 to 600 acres. Table 3-2 provides limits of the length (Maximum Length (L~l)) of sheet flO\v to be used in hydrology studies. Initial Ti values based on average C values for the Land Use Element are also included. These values can be used in planning and design applications as described below'. Exceptions may be approved by the "Regulating Agency" w'hen submitted with a detailed study. Table 3-2 MAXIMliM OVERLAND FLOW LENGTH (LM) & INITIAL T1ME OF CONCENTRATION (Ti) Element* DU/ .5% I 1% I 2% I 3% I 5% I 10% Acre LM I Ti I LM I Ti L"'1 I Ti I LM ITi I LM I Ti LM I Ti Natural I I 50 13.21 70 112.5 85110.91100 110.3 100 1 8.7 100 I 6.9 LDR 11 I 50 12.21 70 111.51 85110.01100 I 9.5 100 I 8.0 100 I 6,4 LDR 12 I 50 11.3 I 70 110.5 I 851 9.21100 I 8.81100 I 7.41100 5.8 LDR 2.9 50 110.7 I 70 110.0 I 85 I 8.8 I 95 ! 8.1 100 I 7.0 1100 I 5.6 MDR 14.3 I 50 110.2 I 70 I 9.61 80 I 8.1 1 951 7.81100 I 6.71100 I 5.3 MDR 17.3 50 I 9.21 6s1 8.4 80 \ 7.41 951 7.0 100 6.0 1100 4.8 MDR 110.9 I 50 I 8.71 6s1 7.91 80 I 6.91 901 6.41100 5.71100 1 4.5 MDR 114.5 1 SO 8.2 I 651 7.41 801 6.5 I 90 I 6.0 1100 I 5.4 100 d"'l •• ::J HDR 124 501 6.71 6s1 6.1 I 75\ 5.1 I 90 I 4.91 951 4.31100 3.5 HDR 143 I 50 I 5.31 651 4.i 751 4.0 I 851 3.81 95 I 3.4 I 100 1 2.7 N.Com 50 I 5.3 I 60 I 4.5 I 75 1 4.0 I 851 3.81 951 3.41100 I 2.7 , G.Com I I 50 I 4.71 60 I 4.1 I 751 3.61 851 3.41 90 I 2.91100 2.4 O.P.lCom I I 50 I 4.21 60 I 3.71 701 3.1 1 801 2.9 90 2.61100 1,2.2 Limited 1.1 1 50 I 4.2 1 60 I 3,71 70 I 3.1 1 80 I 2.91 9012.6 100 '2.2 General I. I I 50 I 3.7 I 60 I 3.21 70 I 2.71 80 I 2.61 90 I 2.3 .100 11.9 *See Table 3-1 for more detailed description 3-12 I I I I I I I I I .1 I I I I I 'I I I I Developed Condition Drainage Study La Costa Greens 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPM'ENT 2.5 -Rainfall Intensity Determination Urban Watershed Overland Time of Flow Nomograph MJ P H:IREPORTSI230l1l5IDEV COND HYDRO-Ol.doc w.o. 2301-15 41412008 3 22 PM - ------ -- ------ Iii IU u.. ~ ~ ~ UJ is IU ~ ::J o ~ IU ~ ?i: 100 \-_1...5-=\---:ffAI'-/--/-I~ ill I-:J Z O~ I--~L.....I-/+-.JE-A-~A---¥-I~I 1 ~ 120 ~ ~ W ~ i= 5; 9 u.. W~~~~_ ... _~_~~10~ """"'--1 '0 EXAMPLE: Given: Walercourse Oislance (D) = 70 Feel Siopo (3) =1.3% Runoff Coefficient (C) :: 0.41 Overland Flow Time (T):: 9.5 Minutes T = 1.6 (1.1-C) VD 3VS OC ~ o - SOURCE: Airport Drainage, Fedoral AVlaUon Admlnlstrallon, 1965 I~IGURE Rational Formula -Overland Time of Flow Nomograph 13-3\ --- ...--------------------~------- I I I I I I I I I I I I I I I I I : I I Developed Condition Drainage Study La Costa Greens 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPM·ENT 2.5 -Rainfall Intensity Determination Gutter & Roadway Discharge-Velocity Chart MJ:p H:\REPORTSI2301\ 151DEV COND HYDRO·01.doc w.o. 2301-15 41412008 3:22 PM I I I I I I I I I I I I I I I I I I I 6 5 4 Q) c-o 3 U5 ID ~ Ci5 '0 Q 2 ~ 1.8 1.6 1.4 1.2 1.0 0.9 0.8 0.7 0.6 0.5 0.4 1<l--1.5·~1 l +-n=.015~1~ __ --2% -n= .0175 ---....:::.:.::.-----! Concrete Gutter Paved RESIDENTIAL STREET ONE SIDE ONLY I I I I I 2 3 4 5 6 7 a 9 10 20 30 Discharge (C.F.S.) EXAMPLE: Given: Q= 10 S =2.5% Chart gives: Depth = 0.4, Velocity = 4.4 f.p.s. 40 50 SOURCE: San Diego County Department of Special District Services Design Manual FIGURE Gutter and Roadway Discharge -Velocity Chart .~ I I I I I I I I I I I I I I I I I I I Developed Condition Drainage Study La Costa Greens 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPM·ENT 2.5 -Rainfall Intensity Determination Manning's Equation Nomograph MJ p H.\REPORTSI2301ll51DEV COND HYDRO-Ol.doc w.o. 2301-15 41412008 3:22 PM I I I I I I I I I I I I I I I I I I en t (5 .g !-cD c. 1ii J!! .5 w a. 0 ..J en EQUATION:V= 1.49 R2I3S'/2 ",0.3 t 0.2 0.15 0.10 0.09 O.OB 0.07 0.06 0.05 0.04 0.03 0.02 ~ t 1ii J!! .5 en ::J 0.01 Ci 0.009 « a:: O.OOB Q 0.007 :::; ::J 0.006 « ~ 0.005 CI >-0.0~4\)~ :c y 0.003 0.002 0.001 0.0009 o.oooa 0.0007 0.0006 0.0005 0.0004 0.0003 n 0.2 0.3 tOA E rs 0.6 t~ 0.8 "" 0.9 1.0 2 3/ 4 5 6 7 a 9 10 20 ~ C?6' '" "'" / ~~ :r GENERAL SOLUTION SOURCE: USDOT, FHWA. HDS-3 (1961) Manning's Equation Nomograph 20 2 1.0 0.9 o.a 0.7 0.6 0.5 0.01 0.02 '; 0.03 0.2 FIGURE ~ I I I I I I I I I I I I I I I I I I I Developed Condition Drainage Study La Costa Greens 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPM'ENT 2.5 -Rainfall Intensity Determination Intensity-Duration Design Chart MJ:p H:IREPORTS\230111510EV CONO HYO'RO-01.doc W.O, 2301-154/4/20083:22 PM ------~ ------ ----- 10.0 r'jS1":':'-,1'" I' 1 9.0 1'''''' ...., r-. 1 6.0 I 7.0 .'-~ ~ l"- I' I'-r-. i"'b-, .~~ h EQUATION 6.0 :: 7.44 P6 D-0.645 "'~ ,t'-I 5.0 ~ t = Intensity (in/hr) 1"1"-, 'b , P6 = 6-l-iour PreCipitation (in) 4'O~ I'. I' "'" t o = Duration (min) 1', i' 3.0 ~ 1'", "' I 1 I 11-..1 I III f'H.J.1I IIl'HII II 1ImHJ.I J'H.IJlmf1'Wt!ll~ I 1'-1 1 1 1 II N-lIIIII I llllllllfH.UJTI' I .... j.. OIl '" "'.11111" ",,,. "","llI'~ ~t I I ~ g! I I t..l'-~" r-.. i'-'N lI"mll ~ ~,., I I,,, jo.'ti'",J 111111111/ ; ~09 1'" r-. "'1--iil ~. n !~8 ~O~ .!!!0.7 ,,5.5 ~. .E . r-. 5.0 g u N u~ r... N 4.0 ~ , 3.5~ 0.511 /1111 III III II I 1111I1I1I1I111!IIII!IIllIllIlIftffi#llli11ll111l1l11-J I IrH+WTNII_3.0 2.0 • ,11 IIIII III I II I till I 1IIIIIIIIIIIIIIIillili 111I11111111111I1mlTI11 I Ilrs I'liJ.II' 0'311=i-ii-;;=-;I-;-" -i-:~' :' .. =-== ---== ..... ==:::, -- - ----------_.-._-----------.. _---------_.-----------------_ .. - "'1'1 trl: ... ,l:llftl '-':::I:::!I:::I= . 1.5 • 1.0 ~I.I-I~ ...... ~ .•. . ,lFIIg=r~]II~~ IIII,~~~,II OO~ II tl.~IIIII.III~1 6 G 7 6 9 10 15 20 30 40 50 1 2 3 4 5 6 1-1-1-f-l+I-I-I-I-I .. I~I_I-I-I.I'I' Minutes Hours -Duralion Intenslty"Duration DeSign Chart -Template Directions for Application: (1) From precipitation maps determine 6 hr and 24 hr amounts for the selected frequency. These maps are included In the County Hydrology Manual (10, 50, and 100 yr maps included In the Design and Procedure Manual). (2) Adjust 6 hr precipitation (if necessary) so that It Is within the range of 45% to 65% of the 24 hr preCipitation (not applicaple to Desert). . (3) Plot 6 hr precipitation on the right side of the chart. (4) Draw a line through the point parallel to the plotted lines. (5) This line is the intensity-duration curve for the location being analyzed. Application Form: (a) Selected frequency ___ year p (b) P6 :: __ In., P24 :: __ .~ :: %(2) 24 (c) Adjusted P6(2):: __ in. (d) tx == __ min . (e) I:: __ in.lhr. Note: This chart replaces the Intensity-Duration-Frequency curves used since 1965 . pi; '. \ .. 1 .. ! 1:51 . 2 "1' 2:ir!"fr \'3:5 1' .r·l. 4.5 .. ,. i;,,~f..5.5·; . ii' Ouratloll','''"", f"l 1'-' Y i j' '1' ,''\' Iii I I : 1 '.:~"".~:::.~ ?·.9Il ~.9~'.\l·?1.i (!.?l! 1.7.DQI9.2~11O.541.11.0Gi 13.y 11.4:~!!i 1?OI .. .. -.? )!.1..?. ~~1.~I.~!,.~~U .. !j,?'Q.I.!!·.~!! .1·.~IW. o.~I~.i .~.5!\ 11.0.,6Q).1,~(;;.H!.'?:J •... 1!1 J"§~_ ~A!~"~:~!.I.'!'.?11.5:~-5. .§.~.Q !.Q:?1.! . .?:~~.1..~.:1?' ... i?"?:.!..1 !Q,1.! .... 1.~ J.:29_1)·1lJ!.,.?'~P.i!:?:),'1 ~'I!QI!!&.41'~!.t..!! . .!H!1.'I,g,,'!!1. J!.1~"II_:U~ 20 1.01! 1,62 2.15.2.69 3.23 3.71 4.31 ·\.U5 5.39 5.93 6.-16 :~':'" i~ .li!: ::~! '~lJU'~J~:IH~lt{~ll;rItt Uf 1n: 1fg _ ....... ~!l .Q~I!9..!9..9.!l.! .. 1!1 I~"!l \,?f!,?:9.~ g,~? ,2,~.~ '~'.~."'" .il.!!!!.l ;):.50, .. Il.o. Q,5,~, 9·.1!9 .1,9.9 .. h~;l. ,!.,~!!. j,q,9 ?:Ig 2 .. ;l!) ,,?:.I1!i .. ;!:~?_ .3 . .19. _._ ....... !lli .9..:.11.. !I~!?.t g.jlg )"9? H.~ .!·.1ll. .!.~~ .. I.,y.~ .. g·.!!.1. ,1l,?5'I.g:1~. _. _.1~9 .. 9,.;11 .. IMJ .!l,.\1!!' .!!,.~~".1.'.9? j,.!!1. J.';I~. 1,§!l ... .1-?!l ..1 .. 0.7 .. 2.9.4 _. __ .~J!.9 .. Q.,?~_ M.1 Q,;!Q .91.~. Q..~!! !:9.~ .. h.1.I! .. "I:;)?" 1·,~!. ) .. \1?.!..I,?!,i ,::~.:j~ ~&~[ ~~ ~1.~: ];U :~;~~ '~f~ ·~;~t ;J~~ ·t~~.:\J~(~:lj;~~· ... -}~~ "~lt· ~:~g ·g:~1 g::}} g~!~:.~~ .g:~~.,. ~:~% -g~~"I'k~~ 'Ug LL.!L!LR E @J - I I I I I I I I I I I I I I I I I I I Developed Condition Drainage Study La Costa Greens 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPM'ENT 2.6 -Rational Method Model Development Summary MJ.p H:IREPORTSI2301115\DEV COND HYDRO-Ol.doc w.o. 2301-15 41412008 3:22 PM I I I I I I I I I I I I I I I I I I Developed Condition Drainage Study La Costa Greens 1.3 2.6 -Rational Method Hydrology Analysis Computer Software Package -AES-2003 Design Storm -100-Year Return Interval Land Use -Single Family Soil Type -Hydrologic soil group D was assumed for all areas. Group D soils have very slow infiltration rates When thoroughly wetted. Consisting chiefly of clay soils' with a high swelling potential, soils with a high permanent water table, soils with clay, pan or clay layer at or near the surface, and shallow soils over nearly impervious materials, Group D soils have a very slow rate of water transmission. Runoff Coefficient -In accordance with the County of San Diego standards, the single family areas were assigned a runoff coefficient of 0.57. Method of Analysis -The Rational Method is the most widely used hydrologi'c model for estimating peak runoff rates. Applied to small urban and semi-urban areas with drainage areas less than 0.5 square miles, the Rational Method relates storm rainfall intensity, a runoff coefficient, and drainage area to peak runoff rate. This relationship is expressed by the equation: Q = CIA, where: Q = The peak runoff rate in cubic feet per second at the point of analysis. C = A runoff coefficient representing the area -averaged ratio of runoff to rainfall intensity. I = The time-averaged rainfall intensity in inches per hour corresponding to the time of concentration. A = The drainage basin area in acres. To perform a node-link study, the total watershed area is divided into subareas which discharge at designated nodes. The procedure for the subarea summation model is as follows: 1. Subdivide the watershed into an initial subarea (generally 1 lot) and subsequent subareas, which are generally less than 10 acres in size. Assign upstream and downstream node numbers to each subarea. 2. Estimate an initial Te by using the appropriate nomograph or overland flow velocity estimation. 3. Using the initial Te, determine the corresponding values of I. Then Q = C I A. RE'kc H.\REPORTS\2301l15\DEV COND HYDRO·03 doc w 0 2301·15 81512008 1.02 PM I I .1 I I I I I I I I I I I I I I I I Oeveloped Condition Drainage Study La Costa Greens 1.3 4. Using Q, estimate the travel time between this node and the next by Manning's equation as applied to the particular channel or conduit linking the two nodes. Then, repeat the calculation for Q based on the revised intensity (which is a function of the revised time of concentration) . The nodes are joined together by links, which may be street gutter flows, drainage swales, drainage ditches, pipe flow, or various channel flows. The AES-99 computer subarea menu is as follows: SUBAREA HYDROLOGIC PROCESS 1. Confluence analysis at node. 2. Initial subarea analysis (including time of concentration calculation).. 3. Pipeflow travel time (computer estimated). 4. Pipeflow travel time (user specified). 5. Trapezoidal channel travel time. 6. Street flow analysis through subarea. 7. User -specified information at node. 8. Addition of subarea runoff to main line. 9. V-gutter flow through area. 10. Copy main stream data to memory bank 11. Confluence main stream data with a memory bank 12. Clear a memory bank At the confluence point of two or more basins, the following procedure is u$ed to combine peak flow rates to account for differences in the basin's times of concentration. This adjustment is based on the assumption that each basin's hydrographs are triangular in shape. 1. If the ·collection streams have the same times of concentration, then the Q values are directly summed, 2. If the collection streams have different times of concentration, the smaller of the tributary Q values may be adjusted as follows: a. The most frequent case is where the collection stream with the longer time of concentration has the larger Q. The smaller Q value is adjusted by the ratio of rainfall intensities. RE:kc H IREPORTS\2301l1SIDEV COND HYDRO·03 doc W.O 2301-15 8/5120081:03 PM I I I I I I I I I I I I. I! I I I I I I Developed Condition Drainage Study La Costa Greens 1.3 b. In some cases, the collection stream with the shorter time of concentration has the larger Q. Then the smaller Q is adjusted by a ratio of the T values. RE:kc H:IREPORTSI2301l15IOEV CONO HYDRO·oS.doc W.O 2301-15 8/5/20061:03 PM I I I I I I I I I I I I I. I, I !I I I I I I Developed Condition Drainage Study La Costa Greens 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPM'ENT 2.7 -Hydraulic Model Development Summary MJ:p H:\REPORTS\2301\15\DEV CDND HYDRO·01.doc W,O, 2301·15 4/4/2008 3:22 PM I I I I I I I I I I I I I I I I I " I Developed Condition Drainage Study La Costa Greens 1.3 2.7 -Storm Drain Hydraulic Analysis STORM METHODOLOGY PURPOSE The Storm Drain Analysis program calculates the hydraulic grade line elevations of a proposed or existing storm drain system given the physical characteristics and the discharge (Q). Currently capability allows for either pressure flow or partial flow with cross sections being either circular or rectangular box. A rectangular open channel can be analyzed as a box cross section, providing the results show that it is flowing partially full throughout the entire system, so that the soffit does not affect the computations. GENERAL DESCRIPTION The program starts the computation for the hydraulic grade line by evaluating the friction losses and the minor losses throughout the system. The junction losses are evaluated by equating pressure plus momentum for the incoming and outgoing flows through the junction. This is accomplished by applying the formula developed by the City of Los Angeles, which establishes that the summation of pressures, ignoring friction, is equal to the average cross section flow area, multiplied by the change in the hydraulic gradient through the junction. The basic flow elevations used for the main lines at either end of the junction that apply to the pressure plus momentum equation depend on the type of flow at each end of the junction. These elevations are determined by computing the drawdown curves for each line. The control elevation for the lateral or lateral system is taken as the average of the hydraulic grade line elevations at both ends of the junction. If the water elevation in the lateral is above this control, the momentum contributed by the lateral in the analysis of the junction is decreased in proportion to the ratio of the area in the lateral below the control to the total area of flow. The point with greater force will be the control point and the pointat the other end of the junction is determined by satisfying the pressure plus momentum equation. Any of these points may be overridden by the backwater curve originating at the main control at the downstream end of the system. If this is the case, then the pressure plus momentum equation is applied to the point or points determined by the backwater curve during the upstream analysis. The above mentioned considerations apply to both partial and pressure flow. When the flow changes from partial to full or from full to partial, the program determines and prints the location where this change occurs. If the flow reaches normal depth within a line, the program determines and prints this location. When the flow changes from supercritical to subcritical because of downstream conditions, RE:kc H.IREPORTS12301l15\oEV COND HYDRO·03.doc W.O 2301-15 8/512008 1 03 PM I I I I I I I I I I I I. I, I I: I I I I Developed Condition Drainage Study La Costa Greens 1.3 it happens through a hydraulic jump, the program determines the precise location of the jump by equating the pressure plus momentum for the two kinds of flow. It prints the jump location pressure plus momentum at the jump and the depth of water before and after the jump. A PROBLEM SET-UP A typical procedure which will allow the engineer to obtain a complete analysis of a storm drain system and also acquire all data necessary to analyze the design is as follows: 1. Establish the main line of the entire storm drain system. Generally speaking, the lines carrying the greater Q will form the main line. In case of comparable Q's, the line contributing the greater force will be the main line. 2. Establish the main line of any lateral system by proceeding upstream from the junction with the main line to the highest upstream inlet. 3. Number the segments of the main line of the entire storm drain system consecutively in the upstream direction to the highest upstream inlet. The channel or conduit, existing or proposed, at the downstream end, which the system joins, should have the lowest number in the system (normally line number 1). 4. Number each lateral system in the same manner, proceeding from its junction with the main line to its highest upstream inlet. 5. For each line, tabulate all pertinent analysis parameters such as: Maximum design flow Q. Adjusted flow Q, to be used in junction analysis. Conduit size and length. Flow line elevations. Minor loss coefficients for the inlets. Entrance loss coefficients for the inlets. Confluence angles at all junctions. For this program the input for the storm drain analysi~ is structured as follows in Column 1 of each line, and all known as cards: 1 -Project description card. S -Control card. 2 -Line data cards. RE:kc H IREPORTS12301l15IDEV COND HYDRO.03 doc w.o. 2301-15 8/5/2008 1:03 PM I I I I I I I I I I· I 'I I I I I I~ I :1 Developed Condition Drainage Study La Costa Greens 1.3 The control card, and line data card are explained as follows: CONTROL CARD (8) This card contains the line number and hydraulic grade line or water surface elevation of the channel or conduit at the downstream end of the main line of a storm drain system. Many drain systems may be included within one job. Each system must begin with a Control Card (8) and must not repeat line numbers from other systems in the same job. CD L2 CTLfTW Number 8 (numeric, required). Line number of the channel or conduit at the downstream end which the system joins (numeri~, required). Hydraulic grade line elevation or water surface elevation of the channel or conduit at the downstream end which the system Joins (numeric, required). LINE CARD (CARD2) This card contains the necessary information for each line of the storm drain system. CD Number 2 (numeric, required). L2 Line number L2. The maximum line number is 300. Line numbers must be in ascending order without duplications (numeric, required). MAXQ ADJ. Q LENGTH FL 1 FL2 CTLfTW Maximum design Q (cfs) (numeric, required). Adjusted Q (cfs) for junction calculations. Adjusted Q equals maximum Q if no entry is made (numeric, optional). Line Length L (feet) (numeric, required). Flow line elevation FL 1 (feet) of conduit at downstream end of line (numeric, required). Flow line elevation FL2 (feet) of conduit at upstream end of line (numeric, required). Maximum allowable hydraulic grade line elevation at upper end of line for structure type 3 or maximum allowable top of water elevation for structure types 1 and RE:kc H:IREPORTS\2301\15Il5EV CONO HYDRO·03 doc w.o.2301·15 8/5/20081'03 PM I I I I I: I I I I I I I I I I I I, I "1 Developed Condition Drainage Study La Costa Greens 1.3 D W S 1 2= 3= KJ KE 2. This entry is optional and is printed in the output as a check value for structural types 1 and 2 (numeric, optional). Diameter D (inches) of circular conduit or Depth D (inches) of rectangular conduit (numeric, required). Width W (inches) or rectangular conduit (numeric, required for rectangular section). Structure type at the upstream end of the line. = Catch basin, headwall, or similar inlet structure for the first upstream line. Box inlet structure with a trash rack for the first upstream line. Manhole, junction structure, in line catch basin, or similar structure for an intermediate line only. (Numeric, required). Junction loss coefficient (Kj) for use with structure type 3. When an entry is made and there is full flow, the junction loss is calculated as Kj times the outlet velocity head, and the pressure plus momentous equation is not applied. If no entry is made or there is partial flow, the junction loss is calculated by pressure plus momentum (numeric, optional). Junction losses are obtained from the Headloss Coefficient table, included at the end of this section. Entrance loss coefficient (Ke) for use with structure types 1,2, and 3 when applicable. When an entry is made, the entrance loss is calculated as Ke times the outlet velocity head. At junctions, this loss is considered only in the case of full flow (numeric, optional). For most entrances KE = 0.10. Entrance losses are based on a conservative basis for each scenario and starting from a 0.2 value. RE:kc H:IREPORTSI2301 1151DEV COND HYDRO·03 doc w.o.2301·15 8/5/20081 03 PM I I I I I I I: I I I I I I I I I Developed Condition Drainage Study La Costa Greens 1.3 KM Minor loss coefficient (Km). Summation of minor loss coefficients for bends, manholes, etc. The minor losses are added to the friction losses for full flow only (numeric, optional). Typical values for KM are: Manholes KM Bends KM = = 0.05 0.002 X 11 = Minor losses are based on a conservative basis for each scenario and considering the bend angles. This values starts at 0.05. Central angle of curve of degrees. LC Control line number. An entry is made for the downstream line only of a main or lateral line system. For the main line of the entire storm drain system, the control line will be that which was entered on the Card 8. For a lateral, the control line is the upstream line from the junction where the lateral connects to the main line or another lateral (numeric, required). L 1,L3,L4 L 1, L3, L4 line numbers entering the structure at the upstream end of the line for structure type 3. L 1 is the main line, 13 and 14 are the laterals (numeric, optional Ai ,A3,A4 J N . for L 1, required for L3 and L4). Ai, A3, A4 (degrees) confluence angles of lines L 1, L3 and L4 to the nearest degree measured from the· prolongation of L2 (numeric, required). J (feet) junction length for structure type 3. This is an entry for obtaining the friction loss across a junctioD, manhole or transition structure for full flow (numeric, optional). Manning's constant, uses 0.013 if no entry is made (numeric, optional). JUNCTION LOSS COEFFICIENT, Kj The junction loss is computed as Kj times the velocity head in the outlet conduit. Note, however, that if the value of Kj is left blank or there is partial flow condition, the pressure plus momentum equation will be used to determine the junction losses. ENTRANCE LOSS COEFFICIENT, KE For use with structure types 1, 2 or 3. Values for ke are 0.10. The entrance loss is computed as Ke times the velocity head in the outlet conduit. RE:kc H IREPORTS\2301115IDEV COND HYDRO·03 doc W 0 2301·15 815120081:03 PM I I I I I I I I I I I I I I !I ! I I· I I Developed Condition Drainage Study La Costa Greens 1_3 MINOR LOSS COEFFICIENT,KM Km is the summation of the loss .coefficients for bends, manholes, etc. The total minor loss is computed as Km times the velocity head in the conduit Typical values for Km are: Manholes: Km 0.05 Bends: Km = 0.002 x Delta Delta = central angle of curve in degrees. Minor losses are added to the friction losses in the hydraulic analysis for full flow only. OTHER VARIABLES • V1, FL 1, D1 and HG1 Refer to Downstream End • V2, FL2, D2 and HG2 Refer to Upstream End • X: Distance in feet from downstream end to point where HG intersects soffit in seal condition. • X(N): Distance in feet from downstream end to point where water surface reaches normal depth by either drawdown or backwater. • X(J): Distance in feet from downstream end to point where hydraulic jump occurs in line. • F(J): The computed force at the Hydraulic Jump • D (BJ): Depth of water before the hydraulic jump (Upstream Side) • D (AJ): Depth of water after the hydraulic jump (Downstream Side) • SEAL: Indicates flow changes from part to full or from full to part • HYD JUMP: Indicates that flow changes from supercritical to sub-critical through a hydraulic jump. . • HJ @ UJT: Indicates that hydraulic jump occurs at the junction at the upstream end of the line. • HJ @ DJT: Indicates that hydraulic jump occurs at the junction at the downstream end of the line. RE kc H.IREPORTSI2301l15\oEV COND HYDRO-03 doc w o. 2301-15 6/5/20061.03 PM ·1 I I I ,I' III I I I I I ~I I ·1 ·1 I. i I· I I :1 I I I I I I I I I I I I I I I I II .1 I Developed Condition Drainage Study La Costa Greens 1.3 CHAPTER 3 RATIONAL METHOD HYDROLOGIC ANALYSIS 100-Year Developed Condition AES Model Output MJ:p H.\REPORTS\230l\15\DEV COND HYDRO-Ol.doc w.o. 2301-15 4/4/2008 3'22 PM I I I I I I I I I I I I I I I I I I I **************************************************************************** RATIONAL METHOD HYDROLOGY COMPUTER PROGRAM PACKAGE Reference: SAN DIEGO COUNTY FLOOD CONTROL DISTRICT 2003,1985,1981 HYDROLOGY MANUAL (c) Copyright 1982-2003 Advanced Engineering Software (aes) Ver. 1.5A Release Date: 01/01/2003 License ID 1239 Analysis prepared by: HUNSAKER & ASSOCIATES -SAN DIEGO 10179 Huennekens Street San Diego, Ca. 92121 (858) 558-4500 FILE NAME: H:\AES2003\2301\15\DEV-100.DAT TIME/DATE OF STUDY: 09:49 04/04/2008 USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION: 2003 SAN DIEGO MANUAL CRITERIA USER SPECIFIED STORM EVENT (YEAR) = 100.00 6-HOUR DURATION PRECIPITATION (INCHES) = 2.700 SPECIFIED MINIMUM PIPE SIZE(INCH) = 18.00 SPECIFIED PERCENT OF GRADIENTS(DEClMAL) TO USE FOR FRICTION SLOPE = 0.90 SAN DIEGO HYDROLOGY MANUAL "C" -VALUES USED FOR RATIONAL METHOD NOTE: USE MODIFIED RATIONAL METHOD PROCEDURES FOR CONFLUENCE ANALYSIS *USER-DEFlNED STREET-SECTIONS FOR COUPLED PIPEFLOW AND STREETFLOW MODEL* HALF-CROWN TO STREET-CROSSFALL: CURB GUTTER-GEOMETRIES: MANNING WIDTH CROSSFALL IN-/ OUT-/PARK-HEIGHT WIDTH LIP HIKE FACTOR NO. (FT) (FT) SIDE / SIDE/ WAY (FT) (FT) (FT) (FT) (n) ========= ================= 1 30.0 20.0 0.018/0.018/0.020 0.67 2.00 0.0312 2 15.0 9.5 0.020/0.020/ 0.33 2.00 0.0312 3 12.0 6.5 0.020/0.020/ ---0.33 2.00 0.0312 GLOBAL STREET FLOW-DEPTH CONSTRAINTS: 1. Relative Flow-Depth = 0.00 FEET as (Maximum Allowable Street Flow Depth) -(Top-of-Curb) 2. (Depth) * (Velocity) Constraint = 6.0 (FT*FT/S) *SIZE PIPE WITH A FLOW CAPACITY GREATER THAN OR EQUAL TO THE UPSTREAM TRIBUTARY PIPE.* ======= 0.167 0.0150 0.125 0.0150 0.125 0.0150 **************************************************************************** FLOW PROCESS FROM NODE 1.00 TO NODE 2.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< ============================================================================ *USER SPECIFIED (SUBAREA) :' RESIDENTAIL (7.3 DU/AC OR LESS) RUNOFF COEFFICIENT = .5700 S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH (FEET) = 65.00 UPSTREAM ELEVATION(FEET) = 323.40 DOWNSTREAM ELEVATION (FEET) = 321.30 ELEVATION DIFFERENCE (FEET) = 2.10 SUBAREA OVERLAND TIME OF FLOW(MIN.) = 5.203 100 YEAR RAINFALL INTENSITY(INCH/HOUR) 6.934 SUBAREA RUNOFF(CFS) 0.55 TOTAL AREA(ACRES) = 0.14 TOTAL RUNOFF(CFS) 0.55 **************************************************************************** FLOW PROCESS FROM NODE 2.00 TO NODE 100.00 IS CODE = 62 »»>COMPUTE STREET FLOW TRAVEL TIME THRU SUBAREA««< »»>(STREET TABLE SECTION # 2 USED)««< UPSTREAM ELEVATION (FEET) = 321.30 DOWNSTREAM ELEVATION(FEET) STREET LENGTH (FEET) = 377.40 CURB HEIGHT(INCHES) = 4.0 STREET HALFWIDTH(FEET) = 15.00 317.20 DISTANCE FROM CROWN TO CROSSFALL GRADEBREAK(FEET) 9.50 INSIDE STREET CROSSFALL(DEClMAL) 0.020 OUTSIDE STREET CROSSFALL(DEClMAL) 0.020 ·1 1 I 1 I I I I I I I I I I I I I I I SPECIFIED NUMBER OF HALF STREETS CARRYING RUNOFF = 1 Manning's FRICTION FACTOR for Streetflow Section(curb-to-curb) **TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) 1.80 STREETFLOW MODEL RESULTS USING ESTIMATED FLOW: STREET FLOW DEPTH(FEET) = 0.28 HALF STREET FLOOD WIDTH(FEET) = 8.27 AVERAGE FLOW VELOCITY(FEET/SEC.) 2.16 PRODUCT OF DEPTH&VELOCITY(FT*FT/SEC.) 0.61 STREET FLOW TRAVEL TIME(MIN.) = 2.91 Tc(MIN.) 8.11 100 YEAR RAINFALL INTENSITY (INCH/HOUR) 5.207 *USER SPECIFIED (SUBAREA) : RESIDENTAIL (7.3 DU/AC OR LESS) RUNOFF COEFFICIENT .5700 S.C.S. CURVE NUMBER (AMC II) = 0 AREA-AVERAGE RUNOFF COEFFICIENT 0.570 SUBAREA AREA(ACRES) 0.83 SUBAREA RUNOFF (CFS) = 2.46 0.0150 TOTAL AREA(ACRES) = 0.97 PEAK FLOW RATE(CFS) "2.88 END OF SuBAREA STREET FLOW HYDRAULICS: DEPTH (FEET) = 0.32 HALF STREET FLOOD WIDTH(FEET) 10.25 FLOW VELOCITY(FEET/SEC.) = 2.40 DEPTH*VELOCITY(FT*FT/SEC.) 0.77 LONGEST FLOWPATH FROM NODE 1.00 TO NODE 100.00 = 442.40 FEET. **************************************************************************** FLOW PROCESS FROM NODE 100.00 TO NODE 100.00 IS CODE = 1 »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< ============================================================================ TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 1 ARE: TIME OF CONCENTRATION (MIN. ) 8.11 RAINFALL INTENSITY (INCH/HR) = 5.21 TOTAL STREAM AREA(ACRES) = 0.97 PEAK FLOW RATE(CFS) AT CONFLUENCE = 2.88 **************************************************************************** FLOW PROCESS FROM NODE 3.00 TO NODE 4.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< ============================================================================ *USER SPECIFIED(SUBAREA): RESIDENTAIL (7.3 DU/AC OR LESS) RUNOFF COEFFICIENT = .5700 S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET) = 65.00 UPSTREAM ELEVATION(FEET) = 321.00 DOWNSTREAM ELEVATION (FEET) = 319.50 ELEVATION DIFFERENCE (FEET) = 1.50 SUBAREA OVERLAND TIME OF FLOW(MIN.) = 5.820 100 YEAR RAINFALL INTENSITY(INCH/HOUR) 6.450 SUBAREA RUNOFF(CFS) = 0.29 TOTAL AREA(ACRES) = 0.08 TOTAL RUNOFF(CFS) 0.29 **************************************************************************** FLOW PROCESS FROM NODE 4.00 TO NODE 100.00 IS CODE = 61 »»>COMPUTE STREET FLOW TRAVEL TIME THRU SUBAREA««< »»>(STANDARD CURB SECTION USED) ««< ============================================================================ UPSTREAM ELEVATION (FEET) = 319.50 DOWNSTREAM ELEVATION (FEET) STREET LENGTH (FEET) = 202.40 CURB HEIGHT(INCHES) = 6.0 STREET HALFWIDTH(FEET) = 16.50 DISTANCE FROM CROWN TO CROSSFALL GRADEBREAK(FEET) 11.40 INSIDE STREET CROSSFALL(DECIMAL) 0.020 OUTSIDE STREET CROSSFALL(DECIMAL) 0.020 SPECIFIED NUMBER OF HALF STREETS CARRYING RUNOFF 1 Manning's FRICTION FACTOR for Streetflow Section(curb-to-curb) **TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) STREETFLOW MODEL RESULTS USING ESTIMATED FLOW: STREET FLOW DEPTH (FEET) = 0.26 HALF STREET FLOOD WIDTH(FEET) = 6.80 AVERAGE FLOW VELOCITY(FEET/SEC.) 1.99 PRODUCT OF DEPTH&VELOCITY(FT*FT/SEC.) = 0.52 1.15 317.20 0.0150 I I I I I I I I I I I I I I I I I I STREET FLOW TRAVEL TIME{MIN.) = 1.70 Tc(MIN.) 7.52 100 YEAR RAINFALL INTENSITY (INCH/HOUR) 5.469 *USER SPECIFIED (SUBAREA) : RESIDENTAIL (7.3 DU/AC OR LESS) RUNOFF COEFFICIENT .5700 S.C.S. CURVE NUMBER (AMC II) = 0 AREA-AVERAGE RUNOFF COEFFICIENT 0.570 SUBAREA AREA{ACRES) 0.55 SUBAREA RUNOFF{CFS) 1.71 ·TOTAL AREA (ACRES) = 0.63 PEAK FLOW RATE (CFS) 1.96 END OF SUBAREA STREET FLOW HYDRAULICS: DEPTH (FEET) = 0.30 HALF STREET FLOOD WIDTH(FEET) 8.74 FLOW VELOCITY{FEET/SEC.) = 2.23 DEPTH*VELOCITY{FT*FT/SEC.) 0.67 LONGEST FLOWPATH FROM NODE 3.00 TO NODE 100.00 = 267.40 FEET. **************************************************************************** FLOW PROCESS FROM NODE 100.00 TO NODE 100.00 IS CODE = »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< »»>AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES««< 1 ============================================================================ TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 2 ARE: TIME OF CONCENTRATION{MIN.) 7.52 RAINFALL INTENSITY(INCH/HR) = 5.47 TOTAL STREAM AREA(ACRES) = 0.63 PEAK FLOW RATE{CFS) AT CONFLUENCE = 1.96 ** CONFLUENCE DATA ** STREAM RUNOFF NUMBER (CFS) 1 2.88 2 1.96 Tc (MIN.) 8.11 7.52 INTENSITY (INCH/HOUR) 5.207 5.469 AREA (ACRE) 0.97 0.63 RAINFALL INTENSITY AND TIME OF CONCENTRATION RATIO CONFLUENCE FORMULA USED FOR 2 STREAMS. ** PEAK STREAM NUMBER 1 2 FLOW RATE RUNOFF (CFS) 4.63 4.75 TABLE ** Tc (MIN. ) 7.52 8.11 INTENSITY (INCH/HOUR) 5.469 5.207 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE{CFS) 4.75 Tc{MIN.) = TOTAL AREA{ACRES) = 1.60 8.11 LONGEST FLOWPATH FROM NODE 1.00 TO NODE 100.00 442.40 FEET. **************************************************************************** FLOW PROCESS FROM NODE 100.00 TO NODE 101.00 IS CODE = 31 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING COMPUTER-ESTIMATED PIPESIZE (NON-PRESSURE FLOW)««< ============================================================================ ELEVATION DATA: UPSTREAM (FEET) = 317.20 DOWNSTREAM (FEET) 313.60 FLOW LENGTH{FEET) = 231.50 MANNING'S N = 0.015 ESTIMATED PIPE DIAMETER(INCH) INCREASED TO 18.000 DEPTH OF FLOW IN 18.0 INCH PIPE IS 8.4 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) 5.90 ESTIMATED PIPE DIAMETER(INCH) = 18.00 NUMBER OF PIPES 1 PIPE-FLOW (CFS) = 4.75 PIPE TRAVEL TlME{MIN.) = 0.65 Tc(MIN.) = 8.76 LONGEST FLOWPATH FROM NODE 1.00 TO NODE 101.00 673.90 FEET. *****************************************************************~********** FLOW PROCESS FROM NODE 101.00 TO NODE 101. 00 IS CODE = 1 »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< ===========================================================================~ TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 1 ARE: TIME OF CONCENTRATION(MIN.) 8.76 RAINFALL INTENSITY (INCH/HR) = 4.95 TOTAL STREAM AREA{ACRES) = 1.60 PEAK FLOW RATE(CFS) AT CONFLUENCE = 4.75 **************************************************************************** I I I I I I I I I I I I I I I I I I I FLOW PROCESS FROM NODE 7.00 TO NODE 8.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< ============================================================================ *USER SPECIFIED (SUBAREA) : RESIDENTAIL (7.3 DU/AC OR LESS) RUNOFF S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET) = UPSTREAM ELEVATION (FEET) = 322.10 DOWNSTREAM ELEVATION (FEET) = 321.30 ELEVATION DIFFERENCE (FEET) = 0.80 SUBAREA OVERLAND TIME OF FLOW(MIN.) = 100 YEAR RAINFALL INTENSITY (INCH/HOUR) NOTE: RAINFALL INTENSITY IS BASED ON Tc SUBAREA RUNOFF(CFS) 0.18 COEFFICIENT = .8500 65.00 3.385 7.114 = 5-MINVTE. TOTAL AREA (ACRES) = 0.03 TOTAL RUNOFF(CFS) = 0.18 **~************************************************************************,* FLOW PROCESS FROM NODE 8.00 TO NODE 101.00 IS CODE = 62 »»>COMPUTE STREET FLOW TRAVEL TIME THRU SUBAREA««< »»>(STREET TABLE SECTION # 2 USED)««< UPSTREAM ELEVATION (FEET) = 321.30 DOWNSTREAM ELEVATION(FEET) STREET LENGTH(FEET) = 598.00 CURB HEIGHT(INCHES) = 4.0 STREET HALFWIDTH(FEET) = 15.00 DISTANCE FROM CROWN TO CROSSFALL GRADEBREAK(FEET) 9.50 INSIDE STREET CROSSFALL(DEClMAL) 0.020 OUTSIDE STREET CROSSFALL(DEClMAL) 0.020 SPECIFIED NUMBER OF HALF STREETS CARRYING RUNOFF 1 313.60 Manning's FRICTION FACTOR for Streetflow Section(curb-to-curb) 0.0150 **TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) 2.53 STREETFLOW MODEL RESULTS USING ESTIMATED FLOW: STREET FLOW DEPTH(FEET) = 0.30 HALF STREET FLOOD WIDTH(FEET) = 9.29 AVERAGE FLOW VELOCITY(FEET/SEC.) 2.50 PRODUCT OF DEPTH&VELOCITY(FT*FT/SEC.) 0.76 STREET FLOW TRAVEL TIME(MIN.) = 3.98 Tc(MIN.) 7.37 100 YEAR RAINFALL INTENSITY (INCH/HOUR) 5.539 *USER SPECIFIED (SUBAREA) : RESIDENTAIL (7.3 DU/AC OR LESS) RUNOFF COEFFICIENT .8500 S.C.S. CURVE NUMBER (AMC II) = 0 AREA-AVERAGE RUNOFF COEFFICIENT 0.850 SUBAREA AREA(ACRES) 0.98 SUBAREA RUNOFF (CFS) 4.61 TOTAL AREA(ACRES) = 1.01 PEAK FLOW RATE (CFS) 4.76 END OF SUBAREA STREET FLOW HYDRAULICS: DEPTH (FEET) = 0.36 HALFSTREET FLOOD WIDTH(FEET) 12.23 FLOW VELOCITY(FEET/SEC.) = 2.89 DEPTH*VELOCITY(FT*FT/SEC.) 1.04 *NOTE: INITIAL SUBAREA NOMOGRAPH WITH SUBAREA PARAMETERS, AND L = 598.0 FT WITH ELEVATION-DROP = 7.7 FT, IS 5.9 CFS, WHICH EXCEEDS THE TOP-OF-CURB STREET CAPACITY AT NODE 101.00 LONGEST FLOWPATH FROM NODE 7.00 TO NODE 101.00 = 663.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE . 101 . 00 TO NODE 101. 00 IS CODE = »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< »»>AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES««< 1 ============================================================================ TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 2 ARE: TIME OF CONCENTRATION(MIN.) 7.37 RAINFALL INTENSITY (INCH/HR) = 5.54 TOTAL STREAM AREA(ACRES) = 1.01 PEAK FLOW RATE(CFS) AT CONFLUENCE = 4.76 ** CONFLUENCE DATA ** STREAM RUNOFF NUMBER (CFS) 1 4.75 2 4.76 Tc (MIN. ) 8.76 7.37 INTENSITY (INCH/HOUR) 4.953 5.539 AREA (ACRE) 1.60 1.01 I I I I I I I I I I I I I I I I I I I RAINFALL INTENSITY AND TIME OF CONCENTRATION RATIO CONFLUENCE FORMULA USED FOR 2 STREAMS. .** PEAK FLOW RATE STREAM RUNOFF NUMBER (CFS) 1 9.00 2 9.00 TABLE ** Tc (MIN. ) 7.37 8.76 INTENSITY ( INCH/HOUR) 5.539 4.953 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE(CFS} 9.00 Tc(MIN.} = TOTAL AREA (ACRES) = 2.61 7.37 LONGEST FLOWPATH FROM NODE 1.00 TO NODE 101. 00 673.90 FEET. **************************************************************************** FLOW PROCESS FROM NODE 101. 00 TO NODE 102.00 IS CODE = 41 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING USER-SPECIFIED PIPESIZE (EXISTING ELEMENT}««< ============================================================================ ELEVATION DATA: UPSTREAM (FEET) 306.25 DOWNSTREAM (FEET) 305.32 FLOW LENGTH(FEET} = 13.25 MANNING'S N = 0.013 ASSUME FULL-FLOWING PIPELINE PIPE-FLOW VELOCITY(FEET/SEC.} 25.79 PIPE FLOW VELOCITY = (TOTAL FLOW}/(PIPE CROSS SECTION AREA) GIVEN PIPE DIAMETER(INCH} = 8.00 NUMBER OF PIPES 1 PIPE-FLOW(CFS} = 9.00 PIPE TRAVEL TIME(MIN.} = 0.01 Tc(MIN.} = 7.38 LONGEST FLOWPATH FROM NODE 1.00 TO NODE 102.00 687.15 FEET. **************************************************************************** FLOW PROCESS FROM NODE 102.00 TO NODE 102.00 IS CODE = 1 »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< ============================================================================ TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 1 ARE: TIME OF CONCENTRATION(MIN.} 7.38 RAINFALL INTENSITY(INCH/HR} = 5.53 TOTAL STREAM AREA(ACRES} = 2.61 PEAK FLOW RATE(CFS} AT CONFLUENCE = 9.00 ****************************************************************************. FLOW PROCESS FROM NODE 5.00 TO NODE 6.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< *USER SPECIFIED (SUBAREA) : RESIDENTAIL (7.3 DU/AC OR LESS) RUNOFF S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET} = COEFFICIENT = .5700 UPSTREAM ELEVATION(FEET} = 321.60 DOWNSTREAM ELEVATION (FEET) = 319.90 ELEVATION DIFFERENCE (FEET) = 1.70 SUBAREA OVERLAND TIME OF FLOW(MIN.} = 100 YEAR RAINFALL INTENSITY (INCH/HOUR) SUBAREA RUNOFF (CFS) 0.26 65.00 5.583 6.626 TOTAL AREA(ACRES} = 0.07 TOTAL RUNOFF(CFS} 0.26 **************************************************************************** FLOW PROCESS FROM NODE 6.00 TO NODE 103.00 IS CODE = 61 »»>COMPUTE STREET FLOW TRAVEL TIME THRU SUBAREA««< »»>(STANDARD CURB SECTION USED} ««< ============================================================================ UPSTREAM ELEVATION(FEET} = 319.90 DOWNSTREAM ELEVATION(FEET} STREET LENGTH(FEET} = 363.70 CURB HEIGHT (INCHES) = 6.0 STREET HALFWIDTH(FEET} = 16.50 DISTANCE FROM CROWN TO CROSSFALL GRADEBREAK(FEET} 11.40 INSIDE STREET CROSSFALL(DEClMAL} 0.020 OUTSIDE STREET CROSSFALL(DEClMAL} 0.020 SPECIFIED NUMBER OF HALF STREETS CARRYING RUNOFF 1 Manning's FRICTION FACTOR for Streetflow Section(curb-to-curb} 313.60 0.0.150 .. ---------------------------------------------------------------------------------------------------------------------------- I I I I I I I I I I I I I I I 'I I I I **TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) 1.50 STREETFLOW MODEL RESULTS USING ESTIMATED FLOW: STREET FLOW DEPTH(FEET) = 0.27 HALF STREET FLOOD WIDTH(FEET) = 6.98 AVERAGE FLOW VELOCITY(FEET/SEC.) 2.48 PRODUCT OF DEPTH&VELOCITY(FT*FT/SEC.) 0.66 STREET FLOW TRAVEL TIME(MIN.) = 2.45 Tc(MIN.) 8.03 100 YEAR RAINFALL INTENSITY (INCH/HOUR) 5.242 *USER SPECIFIED(SUBAREA): RESIDENTAIL (7.3 DU/AC OR LESS) RUNOFF COEFFICIENT .5700 S.C.S. CURVE NUMBER (AMC II) = 0 AREA-AVERAGE RUNOFF COEFFICIENT 0.570 SUBAREA AREA(ACRES) 0.82 SUBAREA RUNOFF(CFS) = 2.45 TOTAL AREA(ACRES) = 0.89 PEAK FLOW RATE(CFS) 2.66 END OF SUBAREA STREET FLOW HYDRAULICS: DEPTH (FEET) = 0.31 HALF STREET FLOOD WIDTH(FEET) 9.09 FLOW VELOCITY(FEET/SEC.) = 2.82 DEPTH*VELOCITY(FT*FT/SEC.) 0.87 LONGEST FLOWPATH FROM NODE 5.00 TO NODE 103.00 = 428.70 FEET. **************************************************************************** FLOW PROCESS FROM NODE 103.00 TO NODE 102.00 IS CODE = 41 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING USER-SPECIFIED PIPESIZE (EXISTING ELEMENT)««< ============================================================================ ELEVATION DATA: UPSTREAM (FEET) = 306.25 DOWNSTREAM (FEET) 305.32 FLOW LENGTH(FEET) = 13.25 MANNING'S N = 0.013 DEPTH OF FLOW IN 8.0 INCH PIPE IS 5.8 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) 9.80 GIVEN PIPE DIAMETER(INCH) = 8.00 NUMBER OF PIPES 1 PIPE-FLOW (CFS) = 2.66 PIPE TRAVEL TIME(MIN.) = 0.02 Tc(MIN.) = 8.05 LONGEST FLOWPATH FROM NODE 5.00 TO NODE 102.00 441.95 FEET. **************************************************************************** FLOW PROCESS FROM NODE 102.00 TO NODE 102.00 IS CODE = 1 »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< »»>AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES««< ============================================================================ TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM TIME OF CONCENTRATION(MIN.) 8.05 RAINFALL INTENSITY (INCH/HR) = 5.23 TOTAL STREAM AREA(ACRES) = 0.89 PEAK FLOW RATE(CFS) AT CONFLUENCE = 2.66 ** CONFLUENCE DATA ** STREAM RUNOFF NUMBER (CFS) 1 9.00 2 2.66 Tc (MIN.) 7.38 8.05 INTENSITY (INCH/HOUR) 5.535 5.232 2 ARE: AREA (ACRE) 2.61 0.89 RAINFALL INTENSITY AND TIME OF CONCENTRATION RATIO CONFLUENCE FORMULA USED FOR 2 STREAMS. ** PEAK STREAM NUMBER 1 2 FLOW RATE RUNOFF (CFS) 11.44 11.17 TABLE ** Tc (MIN. ) 7.38 8.05 INTENSITY (INCH/HOUR) 5.535 5.232 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE(CFS) 11.44 Tc(MIN.) = TOTAL AREA(ACRES) = 3.50 LONGEST FLOWPATH FROM NODE 1.00 TO NODE 7.38 102.00 687.15 FEET. **************************************************************************** FLOW PROCESS FROM NODE 102.00 TO NODE 105.00 IS CODE = 41 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING USER-SPECIFIED PIPESIZE (EXISTING ELEMENT)««< ============================================================================ ELEVATION DATA: UPSTREAM (FEET) 304.49 DOWNSTREAM (FEET) 293.96 FLOW LENGTH(FEET) = 409.55 MANNING'S N = 0.013 I I I I I I I I I I I I I I I I I I DEPTH OF FLOW IN 18.0 INCH PIPE IS 11.3 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 9.83 GIVEN PIPE DIAMETER (INCH) = 18.00 NUMBER OF PIPE-FLOW (CFS) = 11.44 0.69 PIPES 1 PIPE TRAVEL TIME(MIN.) = LONGEST FLOWPATH FROM NODE Tc (MIN.) = 1.00 TO NODE 8.07 105.00 1096.70 FEET. **************************************************************************** FLOW PROCESS FROM NODE 105.00 TO NODE 105.00 IS CODE = »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 1 ARE: TIME OF CONCENTRATION (MIN. ) 8 . 07 RAINFALL INTENSITY (INCH/HR) = 5.22 TOTAL STREAM AREA(ACRES) = 3.50 PEAK FLOW RATE(CFS) AT CONFLUENCE = 11.44 1 **************************************************************************** FLOW PROCESS FROM NODE 11. 00 TO NODE 12.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< *USER SPECIFIED (SUBAREA) : RESIDENTAIL (7.3 DU/AC OR LESS) RUNOFF S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET) = UPSTREAM ELEVATION(FEET) = 313.60 DOWNSTREAM ELEVATION (FEET) = 312.10 ELEVATION DIFFERENCE (FEET) = 1.50 SUBAREA OVERLAND TIME OF FLOW (MIN.) = 100 YEAR RAINFALL INTENSITY(INCH/HOUR) SUBAREA RUNOFF (CFS) 0.11 COEFFICIENT 65.00 5.820 6.450 TOTAL AREA(ACRES) = 0.03 TOTAL RUNOFF(CFS) .5700 0.11 **************************************************************************** FLOW PROCESS FROM NODE 12.00 TO NODE 104.00 IS CODE = 62 »»>COMPUTE STREET FLOW TRAVEL TIME THRU SUBAREA««< »»>(STREET TABLE SECTION * 2 USED)««< ============================================================================ UPSTREAM ELEVATION(FEET) = 312.10 DOWNSTREAM ELEVATION(FEET) STREET LENGTH (FEET) = 325.70 CURB HEIGHT(INCHES) = 4.0 STREET HALFWIDTH(FEET) = 15.00 DISTANCE FROM CROWN TO CROSSFALL GRADEBREAK(FEET) 9.50 INSIDE STREET CROSSFALL(DEClMAL) 0.020 OUTSIDE STREET CROSSFALL(DEClMAL) 0.020 SPECIFIED NUMBER OF HALF STREETS CARRYING RUNOFF 1 Manning's FRICTION FACTOR for Streetflow Section(curb-to-curb) **TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) 1.00 STREETFLOW MODEL RESULTS USING ESTIMATED FLOW: STREET FLOW DEPTH(FEET) = 0.20 HALF STREET FLOOD WIDTH(FEET) = 3.96 AVERAGE FLOW VELOCITY(FEET/SEC.) 3.30 PRODUCT OF DEPTH&VELOCITY(FT*FT/SEC.) 0.65 STREET FLOW TRAVEL TIME(MIN.) = 1.64 Tc(MIN.) 7.46 100 YEAR RAINFALL INTENSITY (INCH/HOUR) 5.494 *USER SPECIFIED (SUBAREA) : RESIDENTAIL (7.3 DU/AC OR LESS) RUNOFF COEFFICIENT .5700 S.C.S. CURVE NUMBER (AMC II) = 0 AREA-AVERAGE RUNOFF COEFFICIENT 0.570 SUBAREA AREA(ACRES) 0.57 SUBAREA RUNOFF(CFS) = 1.79 300.10 0.0150 TOTAL AREA(ACRES) = 0.60 PEAK FLOW RATE(CFS) 1.88 END OF SUBAREA STREET FLOW HYDRAULICS: DEPTH (FEET) = 0.24 HALF STREET FLOOD WIDTH(FEET) 6.14 FLOW VELOCITY(FEET/SEC.) = 3.58 DEPTH*VELOCITY(FT*FT/SEC.) 0.86 LONGEST FLOWPATH FROM NODE 11.00 TO NODE 104.00 = 390.70 FEET. **************************************************************************** FLOW PROCESS FROM NODE 104.00 TO NODE 105.00 IS CODE = 41· ·1 I I I I I I I I I I I I I I I I I I »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING USER-SPECIFIED PIPESIZE (EXISTING ELEMENT)««< ELEVATION DATA: UPSTREAM (FEET) 294.16 DOWNSTREAM (FEET) 293.96 FLOW LENGTH(FEET) = 39.28 MANNING'S N = 0.013 ASSUME FULL-FLOWING PIPELINE PIPE-FLOW VELOCITY(FEET/SEC.) 5.38 PIPE FLOW VELOCITY =. (TOTAL FLOW)/(PIPE CROSS SECTION AREA) GIVEN PIPE DIAMETER (INCH) = 8.00 NUMBER OF PIPES 1 PIPE-FLOW (CFS) = 1.88 PIPE TRAVEL TIME(MIN.) = 0.12 Tc(MIN.) = 7.59 LONGEST FLOWPATH FROM NODE 11.00 TO NODE 105.00 429.98 FEET. **************************************************************************** FLOW PROCESS FROM NODE 105.00 TO NODE 105.00 IS CODE = »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< »»>AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES««< 1 ============================================================================ TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 2 ARE: TIME OF CONCENTRATION(MIN.) 7.59 RAINFALL INTENSITY(INCH/HR) = 5.44 TOTAL STREAM AREA(ACRES) = 0.60 PEAK FLOW RATE (CFS) AT CONFLUENCE = 1.88 ** CONFLUENCE DATA ** STREAM RUNOFF NUMBER (CFS) 1 11.44 2 1.88 Tc (MIN.) 8.07 7.59 INTENSITY (INCH/HOUR) 5.223 5.437 AREA (ACRE) 3.50 0.60 RAINFALL INTENSITY AND TIME OF CONCENTRATION RATIO CONFLUENCE FORMULA USED FOR 2 STREAMS. * * PEAK FLOW RATE STREAM RUNOFF NUMBER (CFS) 1 12.87 2 13 .24 TABLE ** Tc (MIN.) 7.59 8.07 INTENSITY (INCH/HOUR) 5.437 5.223 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE(CFS) 13.24 Tc(MIN.) = TOTAL AREA(ACRES) = 4.10 LONGEST FLOWPATH FROM NODE 1.00 TO NODE 8.07 105.00 1096.70 FEET. **************************************************************************** FLOW PROCESS FROM NODE 105.00 TO NODE 106.00 IS CODE = 41 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING USER-SPECIFIED PIPESIZE (EXISTING ELEMENT)««< ==================================================================~========= ELEVATION DATA: UPSTREAM (FEET) FLOW LENGTH(FEET) = 14.69 ASSUME FULL-FLOWING PIPELINE 293.62 DOWNSTREAM (FEET) MANNING'S N = 0.013 PIPE-FLOW VELOCITY(FEET/SEC.) 7.49 PIPE FLOW VELOCITY = (TOTAL FLOW)/(PIPE CROSS SECTION AREA) GIVEN PIPE DIAMETER (INCH) = 18.00 NUMBER OF PIPES 1 PIPE-FLOW (CFS) = 13.24 0.03 293.58 PIPE TRAVEL TIME(MIN.) = LONGEST FLOWPATH FROM NODE TC(MIN.) = 1.00 TO NODE 8.11 106.00 1111.-39 FEET. **************************************************************************** FLOW PROCESS FROM NODE 106.00 TO NODE 106.00 IS CODE = 1 »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< ============================================================================ TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 1 ARE: TIME OF CONCENTRATION(MIN.) 8.11 RAINFALL INTENSITY (INCH/HR) = 5.21 TOTAL STREAM AREA(ACRES) = 4.10 PEAK FLOW RATE(CFS) AT CONFLUENCE = 13.24 **************************************************************************** FLOW PROCESS FROM NODE 9.00 TO NODE 10.00 IS CODE = 21 I I I I I I I I I I I I I I I I I I I »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< *USER SPECIFIED (SUBAREA) : RESIDENTAIL (7.3 DU/AC OR LESS) RUNOFF COEFFICIENT = .5700 "S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET} = 65.00 UPSTREAM ELEVATION(FEET} = 314.20 DOWNSTREAM ELEVATION(FEET} = 312.10 ELEVATION DIFFERENCE (FEET) = 2.10 SUBAREA OVERLAND TIME OF FLOW(MIN.} = 5.203 100 YEAR RAINFALL INTENSITY (INCH/HOUR) 6.934 SUBAREA RUNOFF (CFS) 0.51 TOTAL AREA (ACRES) = 0.13 TOTAL RUNOFF(CFS} 0.51 **************************************************************************** FLOW PROCESS FROM NODE 10.00 TO NODE 106.00 IS CODE = 62 »»>COMPUTE STREET FLOW TRAVEL TIME THRU SUBAREA««< »»>(S~REET TABLE SECTION # 2 USED}««< UPSTREAM ELEVATION(FEET} = 312.10 DOWNSTREAM ELEVATION(FEET} STREET LENGTH(FEET} = 359.20 CURB HEIGHT(INCHES} = 4.0 STREET HALFWIDTH(FEET} = 15.00 DISTANCE FROM CROWN TO CROSSFALL GRADEBREAK(FEET} 9.50 INSIDE STREET CROSSFALL(DEClMAL} 0.020 OUTSIDE STREET CROSSFALL(DEClMAL} 0.020 SPECIFIED NUMBER OF HALF STREETS CARRYING RUNOFF 1 Manning's FRICTION FACTOR for Streetf10w Section(curb-to-curb} **TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS} 2.18 STREETFLOW MODEL RESULTS USING ESTIMATED FLOW: STREET FLOW DEPTH(FEET} = 0.25 HALF STREET FLOOD WIDTH(FEET} = 6.90 AVERAGE FLOW VELOCITY(FEET/SEC.} 3.50 PRODUCT OF DEPTH&VELOCITY(FT*FT/SEC.} 0.89 STREET FLOW TRAVEL TIME(MIN.} = 1.71 Tc(MIN.} 6.91 100 YEAR RAINFALL INTENSITY(INCH/HOUR} 5.772 *USER SPECIFIED(SUBAREA} : RESIDENTAIL (7.3 DU/AC OR LESS) RUNOFF COEFFICIENT .5700 S.C.S. CURVE NUMBER (AMC II) = 0 AREA-AVERAGE RUNOFF COEFFICIENT 0.570 SUBAREA AREA(ACRES} 1.01 SUBAREA RUNOFF (CFS) 3.32 300.40 0.0150 TOTAL AREA(ACRES} = 1.14 PEAK FLOW RATE (CFS) 3.75 END OF SUBAREA STREET FLOW HYDRAULICS: DEPTH (FEET) = 0.30 HALF STREET FLOOD WIDTH{FEET} 8.98 FLOW VELOCITY(FEET/SEC.} = 3.93 DEPTH*VELOCITY{FT*FT/SEC.} 1.16 LONGEST FLOWPATH YROM NODE 9.00 TO NODE 106.00 = 424.20 FEET. **************************************************************************** FLOW PROCESS FROM NODE 106.00 TO NODE 106.00 IS CODE = »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< »»>AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES««< 1 ============================================================================ TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 2 ARE: TIME OF CONCENTRATION (MIN. ) 6.91 RAINFALL INTENSITY{INCH/HR} = 5.77 TOTAL STREAM AREA{ACRES} = 1.14 PEAK FLOW RATE{CFS} AT CONFLUENCE = 3.75 ** CONFLUENCE DATA ** STREAM RUNOFF NUMBER {CFS} 1 13.24 2 3.75 Tc {MIN. } 8.11 6.91 INTENSITY (INCH/HOUR) 5.209 5.772 AREA {ACRE} 4.10 1.14 RAINFALL INTENSITY AND TIME OF CONCENTRATION RATIO CONFLUENCE FORMULA USED FOR 2 STREAMS. ** PEAK FLOW RATE TABLE ** STREAM RUNOFF Tc INTENSITY I I 1- I I I I I I I I I I I I I I I I NUMBER 1 2 (CFS) 15.70 16.63 (MIN. ) 6.91 8.11 ( INCH/HOUR) 5.772 5.209 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE(CFS) 16.63 Tc(MIN.) = TOTAL AREA (ACRES) = 5.24 8.11 LONGEST FLOWPATH FROM NODE 1.00 TO NODE 106.00 1111. 39 FEET. **************************************************************************** FLOW PROCESS FROM NODE 106.00 TO NODE 13.00 IS CODE = 41 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING USER-SPECIFIED PIPESIZE (EXISTING ELEMENT) ««< ELEVATION DATA: UPSTREAM (FEET) 293.25 DOWNSTREAM (FEET) 293.00 FLOW LENGTH(FEET) = 24.53 MANNING'S N = 0.013 ASSUME FULL-FLOWING PIPELINE PIPE-FLOW VELOCITY(FEET/SEC.) 9.41 PIPE FLOW VELOCITY = (TOTAL FLOW)/(PIPE CROSS SECTION AREA) GIVEN PIPE DIAMETER(INCH) = 18.00 NUMBER OF PIPES 1 PIPE-FLOW (CFS) = 16.63 PIPE TRAVEL TlME(MIN.) = 0.04 Tc(MIN.) = 8.15 LONGEST FLOWPATH FROM NODE 1.00 TO NODE 13.00 1135.92 FEET. +--------------------------------------------------------------------------+ I -Start of northerly flow I I I I I +--------------------------------------------------------------------------+ **************************************************************************** FLOW PROCESS FROM NODE 14.00 TO NODE 15.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< ============================================================================ *USER SPECIFIED (SUBAREA) : RESIDENTAIL (7.3 DU/AC OR LESS) RUNOFF COEFFICIENT = .5700 S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET) = 65.00 UPSTREAM ELEVATION(FEET) = 324.50 DOWNSTREAM ELEVATION (FEET) = 322.20 ELEVATION DIFFERENCE (FEET) = 2.30 SUBAREA OVERLAND TIME OF FLOW(MIN.) = 5.048 100 YEAR RAINFALL INTENSITY (INCH/HOUR) 7.070 SUBAREA RUNOFF(CFS) = 0.64 TOTAL AREA (ACRES) = 0.16 TOTAL RUNOFF(CFS) 0.64 **************************************************************************** FLOW PROCESS FROM NODE 15.00 TO NODE 16.00 IS CODE = 62 »»>COMPUTE STREET FLOW TRAVEL TIME THRU SUBAREA««< »»>(STREET TABLE SECTION # 3 USED)««< ============================================================================ UPSTREAM ELEVATION(FEET) = 322.20 DOWNSTREAM ELEVATION(FEET) STREET LENGTH (FEET) = 220.70 CURB HEIGHT(INCHES) 4.0 STREET HALFWIDTH(FEET) = 12.00 DISTANCE FROM CROWN TO CROSSFALL GRADEBREAK(FEET) 6.50 INSIDE STREET CROSSFALL(DEClMAL) 0.020 OUTSIDE STREET CROSSFALL(DEClMAL) 0.020 SPECIFIED NUMBER OF HALF STREETS CARRYING RUNOFF 1 Manning's FRICTION FACTOR for Streetf10w Section(curb-to-curb) **TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) STREETFLOW MODEL RESULTS USING ESTIMATED FLOW: STREET FLOW DEPTH(FEET) = 0.25 6.88 2.77 HALF STREET FLOOD WIDTH(FEET) = AVERAGE FLOW VELOCITY(FEET/SEC.) PRODUCT OF DEPTH&VELOCITY(FT*FT/SEC.) STREET FLOW TRAVEL TlME(MIN.) = 1.33 100 YEAR RAINFALL INTENSITY (INCH/HOUR) *USER SPECIFIED(SUBAREA) : 0.70 Tc (MIN.) 6.083 RESIDENTAIL (7.3 DUlAC OR LESS) RUNOFF COEFFICIENT S.C.S. CURVE NUMBER (AMC II) = 0 1.72 6.37 .5700 317.60 0.0150 I I I I I I I I I I I I I I I I I I I AREA-AVERAGE RUNOFF COEFFICIENT SUBAREA AREA(ACRES) 0.62 TOTAL AREA (ACRES) = 0.78 0.570 SUBAREA RUNOFF(CFS) PEAK FLOW RATE(CFS) END OF SUBAREA STREET FLOW HYDRAULICS: DEPTH (FEET) = 0.29 HALF STREET FLOOD WIDTH(FEET) 8.60 2.15 2.70 FLOW VELOCITY(FEET/SEC.) = 3.05 DEPTH*VELOCITY(FT*FT/SEC.) 0.88 LONGEST FLOWPATH FROM NODE 14.00 TO NODE 16.00 = 285.70 FEET. END OF STUDY SUMMARY: TOTAL AREA (ACRES) PEAK FLOW RATE (CFS) 0.78 TC(MIN.) = 2.70 6.37 ============================================================================ ============================================================================ END OF RATIONAL METHOD ANALYSIS I ,I, I, I' "I, I I I, I I I I I 'I I, !'I :1, I I IV I I I I I I I I I I I I I I I I I I I Developed Condition Drainage Study La Costa Greens 1.3 Chapter 4 STORM DRAIN HYDRAULIC ANALYSIS MJ P H.IREPORTSI23011151DEV eOND HYDRO·Ol.doc w.o. 2301-15·41412008 3:22 PM ---- -- -.. - --- -- --- -- LA COUNTY PUBLIC WORKS STORM DRAIN ANALYSIS REPT: PC/RD4412.1 03/20/08 (INPUT) DATE: PAGE 1 PROJECT: LA COSTA GREENS 1.3 DEVELOPED 100 YEAR DESIGNER: P BRAND CD L2 MAX Q ADJQ LENGTH FL 1 FL 2 CTL/TW D W S N KJ KE KM LC L1 L3 L4 A1 A3 A4 J 8 9 297.10 2 10 16.6 16.6 24.53 293.00 293.25 297.10 24. o. 3 0.013 0.50 0.20 0.05 9 11 0 0 18. o. o. 4.00 2 11 13 .2 13.2 14.69 293.58 293.62 0.00 24. o. 3 0.013 0.50 0.20 0.05 0 12 30 0 83. O. o. 4.00 2 12 11.4 11.4 127.80 293.96 296.45 0.00 24. o. 3 0.15 0.20 0.33 0 13 0 0 O. o. o. 5.00 0.013 2 13 11.4 11.4 120.01 0.013 296.78 298.01 0.00 24. o. 3 0.15 0.20 0.33 0 14 0 0 o. O. o. 5.00 2 14 11.4 11.4 144.80 298.34 303.99 0.00 24. O. 3 0.50 0.20 0.33 0 15 16 0 90. 90. o. 5.00 0.013 2 15 8.5 8.5 13 .25 0.013 304.99 306.25 0.00 12. O. 1 0.50 0.00 0.05 0 0 0 0 O. O. O. 4.00 2 16 2.7 2.7 13 .25 0.013 305.32 306.25 0.00 8. O. 1 0.50 0.00 0.05 14 0 0 0 O. O. O. 4.00 2 30 2.4 2.4 39.28 0.013 293.62 293.83 0.00 12. O. 1 0.50 0.00 0.05 11 0 0 0 O. O. O. 4.00 - --- -- -- - ------ -- -- LA COUNTY PUBLIC WORKS STORM DRAIN ANALYSIS REPT: PC/RD4412.2 03/20/08 DATE: PAGE 1 PROJECT: LA COSTA GREENS 1.3 DEVELOPED 100 YEAR DESIGNER: P BRAND LINE Q D W DN DC FLOW SF-FULL V 1 V 2 FL 1 FL 2 HG 1 HG 2 D 1 D 2 TW TW NO (CFS) (IN) (IN) (FT) (FT) TYPE (FT/FT) (FPS) (FPS) (FT) (FT) CALC CALC (FT) (FT) CALC CK REMARKS 9 HYDRAULIC GRADE LINE CONTROL 297.10 10 16.6 24 0 1.27 1.47 FULL 0.00538 5.3 5.3 293.00 293.25 297.10 297.25 4.10 4.00 0.00 0.00 11 13 .2 24 0 2.00 1.30 FULL 0.00340 4.2 4.2 293.58 293.62 297.73 297.80 4.15 4.18 0.00 0.00 12 11.4 24 0 0.83 1.21 FULL 0.00254 3.6 3.6 293.96 296.45 298.07 298.46 4.11 2.01 0.00 0.00 13 11.4 24 0 1.00 1.21 PART 0.00254 4.2 12.9 296.78 298.01 298.39 298.66 1. 61 0.65 0.00 0.00 HYD JUMP X = 0.00 X(N) 0.00 X(J) = 7.65 F(J) 3.33 D(BJ) 0.96 D(AJ) 1. 52 14 11.4 24 0 0.69 1.21 PART 0.00254 11.9 5.7 298.34 303.99 299.03 305.20 0.69 1.21 0.00 0.00 X = 0.00 X(N) 10.67 15 8.5 12 0 0.66 0.99 FULL 0.05692 10.8 10.8 304.99 306.25 306.66 307.42 1.67 1.17 309.24 0.00 14 HYDRAULIC GRADE LINE CONTROL 298.84 16 2.7 8 o 0.47 0.65 PART 0.04992 9.1 7.8 305.32 306.25 305.85 306.90 0.53 0.65 307.84 0.00 11 HYDRAULIC GRADE LINE CONTROL 297.49 30 2.4 12 o 0.76 0.66 FULL 0.00454 3.1 3.1 293.62 293.83 297.49 297.68 3.87 3.85 297.82 0.00 -- -- -------- ---- POINT WHERE HG INTERSECTS SOFFIT IN SEAL CONDITION V 1, FL 1, D 1 AND HG 1 V 2, FL 2, D 2 AND HG 2 X -DISTANCE IN FEET X(N) -DISTANCE IN FEET BACKWATER REFER TO DOWNSTREAM END REFER TO UPSTREAM END FROM DOWNSTREAM END TO FROM DOWNSTREAM END TO POINT WHERE WATER SURFACE REACHES NORMAL DEPTH BY EITHER DRAWDOWN OR X(J) -DISTANCE IN FEET FROM DOWNSTREAM END TO POINT WHERE HYDRAULIC JUMP OCCURS IN LINE F(J) -THE COMPUTED FORCE AT THE HYDRAULIC JUMP D(BJ) -DEPTH OF WATER BEFORE THE HYDRAULIC JUMP (UPSTREAM SIDE) D(AJ) -DEPTH OF WATER AFTER THE HYDRAULIC JUMP (DOWNSTREAM SIDE) SEAL INDICATES FLOW CHANGES FROM PART TO FULL OR FROM FULL TO PART HYD JUMP INDICATES THAT FLOW CHANGES FROM SUPERCRITICAL TO SUBCRITICAL THROUGH A HYDRAULIC JUMP HJ @ UJT INDICATES THAT HYDRAULIC JUMP OCCURS AT THE JUNCTION AT THE UPSTREAM END OF THE LINE HJ @ DJT INDICATES THAT HYDRAULIC JUMP OCCURS AT THE JUNCTION AT THE DOWNSTREAM END OF THE LINE EOJ 3/20/2008 14: 9 - -- , ILA COUNTY PUBLIC WORKS I PROJECT: La Costa Green 1.3 Developed 2301\15\basin IDESIGNER: RLE CD L2 MAX Q ADJ Q LENGTH FL 1 FL 2 CTL/TW D 287.88 STORM DRAIN ANALYSIS (INPUT) W S KJ KE KM 2 2 16.6 16.6 62.53 286.96 288.75 0.00 24. O. 1 0.50 0.20 0.00 I I REPT: PC/RD4412.1 DATE: 07/21/08 PAGE 1 LC L1 L3 L4 A1 A3 A4 J N 1 o o o O. O. O. 4.00 0.Ol3 I ~-rA~-r(~4 f~f8 0~ :i:::. \gJ~£l--r 1d€P-r/A I t-J \{ 6P--r I I -'2. EL>qLR -t D. '11- .-'-01.-W -I I I I I I I I I I ILA COUNTY PUBLIC WORKS STORM DRAIN ANALYSIS I PROJECT: La Costa Green 1.3 Developed 2301\15\basin IDESIGNER: RLE LINE Q D W DN NO (CFS) (IN) (IN) (FT) DC (FT) FLOW SF-FULL TYPE (FT/FT) 11 HYDRAULIC GRADE LINE CONTROL 287.88 I 2 16.6 24 o 0.92 1. 47 PART 0.00538 I I I I I I I I I I I I I I V 1 V 2 (FPS) (FPS) 11. 0 6.7 FL 1 (FT) 286.96 FL 2 (FT) 288.75 HG 1 CALC 287.93 HG 2 CALC 290.22 D 1 (FT) 0.97 D 2 (FT) 1.47 TW CALC 291. 06 REPT: PC/RD4412.2 DATE: 07/21/08 PAGE 1 TW CK 0.00 REMARKS I I I I I I I I I I I I I I I I I I I VI, FL 1, D 1 AND HG 1 REFER TO DOWNSTREAM END V 2, X X(N) X(J) F(J) D(BJ) D(AJ) FL 2, D 2 AND HG 2 REFER TO UPSTREAM END -DISTANCE IN FEET FROM DOWNSTREAM END TO POINT WHERE HG INTERSECTS SOFFIT IN SEAL CONDITION _ DISTANCE IN FEET FROM DOWNSTREAM END TO POINT WHERE WATER SURFACE REACHES NORMAL DEPTH BY EITHER DRAWDOWN OR BACKWATER -DISTANCE IN FEET FROM DOWNSTREAM END TO POINT WHERE HYDRAULIC JUMP OCCURS IN LINE -THE COMPUTED FORCE AT THE HYDRAULIC JUMP -DEPTH OF WATER BEFORE THE HYDRAULIC JUMP (UPSTREAM SIDE) -DEPTH OF WATER AFTER THE HYDRAULIC JUMP (DOWNSTREAM SIDE) SEAL INDICATES FLOW CHANGES FROM PART TO FULL OR FROM FULL TO PART HYD JUMP INDICATES THAT FLOW CHANGES FROM SUPERCRITlCAL TO SUBCRITlCAL THROUGH A HYDRAULIC JUMP HJ @ UJT INDICATES THAT HYDRAULIC JUMP OCCURS AT THE JUNCTION AT THE UPSTREAM END OF THE LINE HJ @ DJT INDICATES THAT HYDRAULIC JUMP OCCURS AT THE JUNCTION AT THE DOWNSTREAM END OF THE LINE EOJ 7/21/2008 17: 8 I I I I I I I I I I I I I I I I I I I Friction Method Solve For Roughness Coefficient Channel Slope Diameter Discharge Normal Depth Flow Area Wetted Perimeter Top Width Critical Depth Percent Full Critical Slope Velocity Velocity Head Specific Energy Froude Number Maximum Discharge Discharge Full Slope Full Flow Type Downstream Depth Length Number Of Steps Upstream Depth Profile Description Profile Headloss Average End Depth Over Rise Normal Depth Over Rise Downstream Velocity Upstream Velocity Starting WSEL-Basin Outlet Manning Formula Normal Depth SuperCritical 0.013 2.86 % 24 in 16.60 ft3/s 0.92 ft 1.41 ft2 2.98 ft 1.99 ft 1.47 ft 46.1 % 0.00680 ftlft 11.74 ftls 2.14 ft 3.06 ft 2.46 41.15 ft3/s 38.26 ft3/s 0.00539 ftlft 0.00 ft 0.00 ft o 0.00 ft 0.00 ft 0.00 % 46.07 % Infinity ftls Infinity ftls ,« Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.066.00] 712112008 5:07:08 PM 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 Page 1 of 2 ------------------- PREPARED FOR: HUNSAKER & ASSOCIATES SAN DIEGO. INC PlANNING 9707 Waples Street ENGINEERING San Diego. Ca 92121 SURVEYING PH(8S8)SS8-lS00· FX(858)SS8·1414 -------~-------------1--- SCALE 1"=40· STORM LEGEND FOR SHEET 1 LA COSTA GREENS 1.3 OF III 'j 5 1 I') C\I ~- ~ CITY OF CARLSBAD, CALIFORNIA RI\0510\8.Hycl\0510$HI6-DEV-STCRM.clwgrJMllr-19-200BI13IOO I I I I 1,- I I I- I v I I I I I I ,I i-I I I I I I I I I I I I I I I I I I I I' I I Developed Condition Drainage Study La Costa Greens 1.3 Chapter 5 IN.LET SIZING MJ p H:IREPORTS1230l1l51OEV COND HYDRO·Ol.doc W,o. 2301-15 41412006 3'22 PM I I I I I I I I I I I I I I I I I I I LA COSTA GREENS 1.3 -CURB INLET SIZING Type Inlet Street Surface of at SIope1 Flow Inlet Node S (%) Q (cfs) ON-GRADE 101 2.00% 8.5 ON-GRADE 103 2.00% 2.7 ON-GRADE 104 4.80% 2.4 ON-GRADE 106 4.75% 3.8 1 From street profiles in Improvement Plans 2 From AES ouput Gutter Depression a (ft) 0.33 0.33 0.33 0.33 3 From Manning's Equation: Q = (1.49/n)*A*S1/2*R2/3 Flow Required Depth3 Length of y (ft) Opening4 (ft) 0.41 18.9 0.30 7.6· 0.24 7.9 0.29 10.9 The hydraulic radius, R, and area, A, are expressed as a function of the flow depth, y. Typical cross-section of a Type G gutter is used for the analysis. 4 Per City of Carlsbad Standards From Equation: Q = 0.7L(a+y)'\3/2 5 Length shown on plans (Required Length of Opening + 1 foot) 6 The flow conveyed by a 20 foot maximum length inlet is 8.9 cfs at this location. The remaining flow at node 101 will flow by and be captured by the inlet at node 104. Use Length 5 (ft) 20 6 9 9 12 H:\EXCEL\2301\ 15\INLETS-CARLSBAD.xls 41712008 1 of 1 I I I I I I· I. '1 I I, I VI I I I I' I I I I 1.1 I I I I I: I I I I I I I I I I I I I I II Developed Condition Drainage Study La Costa Greens 1.3 Chapter 6 HYDROLOGY MAP MJ P H.IREPORTSI2301\151DEV COND HYDRO·01 doc w.o. 2301-15 4/4/2008 3 22 PM -.','::- I I I I I I I I I I I I I I I I I I I Developed Condition Drainage Study La Costa Greens 1.3 APPENDIX MJ:de H:IREPORTSI23011151DEV COND HYDR()'02.doc w.o.2301·15 6110120062:40 PM I I I I I I I I I I I I I I I I I I I PLANNING ENGINEERING SURVEYING IRVINE LOS ANGELES RIVERSIDE SAN DIEGO DAVE HAMMAR LEX WILLIMAN ALISA VIALPANDO DAN SMITH RAY MARTIN HUNSAKER &ASSOCIATES 5 AND lEG 0, INC. DRAINAGE STUDY for LA COSTA GREENS NEIGHBORHOODS 1.2 & 1.3 DEVELOPER IMPROVEMENTS City of Carlsbad, California Prepared for: Real Estate Collateral Management Company c/o Morrow Development 1903 Wright Place Suite 180 Carlsbad, CA 92008 W.O. 2352-146/2352-170 Hunsaker & Associates San Diego, Inc. August 21,2006 CHUCK CATER _____________ _ 10179 Huennekens St. San Diego, CA 92121 (858) 5584500 PH (858) 558-1414 FX www.HunsakerSD.com Info@HunsakerSD.com Raymond L. Martin, R.C.E. Vice President AD:kc H:IREPORTSI23521146\A02.doc W.O 2352·146/170 8/21/2008 10.27 AM I I I I I I I I I I I I I I I I I La Costa Greens Neighborhoods 1.2 & 1.3 -Developer Improvements City of Carlsbad, California Drainage Study August, 2006 Dear Sir/Madam, All plan check comments have been addressed such that we deem this Drainage Study complete. Further discussions are welcome in regards to this Drainage Study. The comments regarding the Drainage Study for Pocina Property have been addressed in the following manner: 1. Chapter 4 -Hydraulic Analysis 4.1 -Neighborhood 1.2 Storm CAD Model Output R: The title of the Hydraulic Model has been updated to "La Costa Greens- Developed Conditions: Neighborhood 1.2 (South)" for better understanding. The CDS Unit information sheet shows proper storm drain stationing for better understanding and locating within plans. 4.2 -Neighborhood 1.3 Storm CAD Model Output R: The title of the Hydraulic Model has been updated to "La Costa Greens- Developed Conditions: Neighborhood 1.3" for better understanding. 2. Chapter 5 -Inlet Sizing R: The inlet calculations spreadsheet have been updated by labeling the proposed inlets to its respective neighborhood. 3. Chapter 6 -AC Berm Opening Design R: The proposed AC Berm Opening is located in Node 218 instead of Node 214. AC Berm Opening spreadsheet has been updated for better understanding. See Developed Conditions Hydrology Map in Chapter 9 -Hydrology Exhibits at the end of this report. H:\REPORTS\2352\146\Response to June, 2006 City of Carlsbad (ORAINAGE).doc 8/11/2006 1 I I I I I I I I I I I I I I I I I I I 4. Chapter 7 -Desilt Basin Design 7.1 -100-Year Mass-Graded Condition AES Model Output (for Riser and Desilt Basin Design Only) R: The Mass-Graded Condition AES Model has been updated to match Desilt Basin bottom elevation. 7.2 -Riser and Desilt Basin Calculations < R: This section has been updated to separate design calculations for each proposed . desilt basin. 5. Chapter 9 -Hydrology Exhibits R: The Developed Conditions Hydrology Map and Site Exhibit have been updated per comments in regards of labeling of exhibits in reference of the table of contents and showing 100-Year flows at each proposed inlet and outlet structure within the project site. H:\REPORTS\2352\146\Response to June, 2006 City of Carlsbad (DRAINAGE).doc 8/11/2006 2 I I I I I I I I' I I I I I !I I I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 TABLE OF CONTENTS Chapter 1 -Executive Summary 1.1 Introduction 1.2 Vicinity Maps 1.3 Existing Condition 1 .4 Proposed Project 1.5 Summary of Results 1.6 Conclusion 1.7 References Chapter 2 • Methodology & Model Development 2.1 City of Carlsbad Engineering Standards 2.2 County of San Diego Drainage Design Criteria 2.3 Design Rainfall Determination • 1 DO-Year, 6-Hour Rainfallisopfuvial Map • 1 DO-Year, 24-Hour Rainfall Isopluvial Map 2.4 Runoff Coefficient Determination 2.5 Rainfall Intensity Determination • Maximum Overland Flow Length & Initial Time of Concentration Table SECTION II' • Urban Watershed Overland Time of Flow Nomograph • Gutter & Roadway Discharge-Velocity Chart • Manning's Equation Nomograph • Intensity-Duration Design Chart 2.6 Rational Method Model Development Summary 2.7 Hydraulic Model Development Summary Chapter 3 -Rational Method Hydrologic Analysis III (100·Year Developed Condition AES Model Output) Chapter 4 -Hydraulic Analysis 4.1 Neighborhood 1.2 StormCAD Model Output 4.2 Neighborhood 1.3 Storm CAD Model Output Chapter 5 -Inlet Sizing IV V AH:ad H:IREPORTS\235Z1146IAOZ.doc W.O.2352·1461170 8121/2006 8:23 AM I I I I I I I I I I I I I I I I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 Chapter 6 -AC Berm Opening Design Chapter 7 -Desilt Basin Design 7.1 100-Year Mass-Grade Condition AES Model Output (For Riser and Desilt Basin Design Only) 7.2 Riser and Desilt Basin Calculations Chapter 8 -Rip Rap Design Chapter 9 -Appendices Appendix 9.1 VI VII VIII IX Hydrologic Analysis Excerpts from "Mass-Graded Hydrology Study for La Costa Greens Neighborhoods 1.1-1.3 & EI Camino Real Widening" Appendix 9.2 Hydrologic Analysis Excerpts from "Drainage Study for Alicante Road -North of Poinsettia" Appendix 9.3 Hydraulic Analysis Excerpts from "Drainage Study for Alicante Road -North of Poinsettia" Appendix 9.4 Revised Hydraulic Analysis for Existing Storm Drain and Revised Headwater Depth Calculation for Existing D-34 Headwall (per Drawing No. 397 -2F) Appendix 9.5 Excerpts from Drawing No. 397 -2F "La Costa Greens -Alicante Road (North)", Sheets 9-11 Chapter 10 -Hydrology Exhibits Exhibit 10.1 Developed Condition Hydrology Map Exhibit 10.2 Site Exhibit X AH:ad H:IREPORTS\23521146\A02.doc . W.O.2352·146/170 8121/2006 8'23 AM r-~~~-~-~------ 1 I -I 'I, 'I' -I 'I I I I I I . I I I 1 'I I, 'I - I I I I I I I I I I I I I I I I I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 EXECUTIVE SUMMARY 1.1 • Introduction The La Costa Greens Neighborhoods 1.2 & 1.3 site is located north of Poinsettia Lane and west of Alicante Road in the City of Carlsbad, California. The project site is also bound by EI Camino Real directly to the west and La Costa Greens Neighborhood 1.1 to the northeast. The vicinity maps below have been included to illustrate the project site's location. This drainage study will address: • 100-Year Peak Flowrates for Mass-Graded and Developed Conditions • Hydraulic Calculations • Inlet Sizing • AC Berm Opening Design • Riser and Desilt Basin Design 1.2 -Vicinity Maps VICINITY MAP NTS LA COSTA VICINITY MAP Mrs AH:ad H:IREPORTS123521146\A02.doc W.O.23S2-146/170 8121/2006 8:23 AM I I I I . 1 I I I I I I I I I I I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 1.3 -Existing Condition The La Costa Greens Neighborhoods 1.2 & 1.3 site is part of the La Costa Greens development in the City of Carlsbad, California. Located in the Batiquitos . watershed, the site currently consists of two mass-graded pads per Drawing No, 397-2Y. The site does not receive any offsite runoff . Runoff from the mass-graded pads drains into two individual desiltation 'basins prior to discharging from the mass-graded site towards the south. The peak discharge flows southerly towards existing storm drain systems in Poinsettia Lane and Alicante Road North, per Drawings No. 397-2H and 397-2F respectively, at two separate locations: first towards an existing 0-34 headwall at the northwest corner of the Poinsettia Lane-Alicante Road intersection and secondly towards an existing U-Type headwall near Poinsettia Lane Sta. 23+00. Both eXisting storm drain systems discharge into the Alicante Detention Basin located at the southeast corner of the Poinsettia Lane-Alicante Road intersection (see Exhibit 9.2 -Site Exhibit). The runoff from the previously mentioned basin is drained via a double 8-ft by 5-ft reinforced concrete box to an unnamed tributary of San Marcos Creek. The discharge then flows in a southerly direction along the site boundary of the' La Costa Greens Golf Course until it eventually drains under Alga Road via three 96" RCP culverts and finally discharges into San Marcos Creek towards Batiquitos Lagoon. 1.4 -Proposed Project The construction of the La Costa Greens Neighborhoods 1.2 & 1.3 site, per this study, will include only the developer improvements for the southern portion of Neighborhood 1.2 (located south of the Vida Roble cul-de-sac), and the RV Storage Site and an interim portion of Street "An (approximately from Sta. 10+00 to Sta. 19+48) for Neighborhood 1.3. The developer improvements for Neighborhood 1.2 include the full development of the Camino Vida Roble cul-de-sac and a portion of Street "An (approximately from Sta. 23+00 to Sta. 29+65), including underground utilities. In its ultimate condition, the La Costa Greens Neighborhood 1.2 site will most likely be used as a commercial development. Ultimately, the La Costa Greens Neighborhood 1.3 site will consist of a multi-family residential development with the small portion towards the center of the site dedicated to the proposed RV Storage site. For now, the future multi-family residential sit will remain mass-graded. This report does not include discussion on future residential development of the adjacent La Costa Greens Neighborhood 1.1, since it will. remain in its current mass- graded state. It should also be noted that the northern portion of Neighborhood 1.2, located north of the Camino Vida Roble cul-de-sac, will also remain in its mass- graded state. AH:ad H:IREPORTS\23521146\A02.doc W.O.2352-1461170 612112006 8:23 AM I I I I I I I I I I I I I I I I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 Runoff from the Camino Vida Roble cul-de-sac drains towards a proposed sump curb inlet and is conveyed by an 18-inch RCP system towards the center of Street "A" (between Sta. 23+00 to Sta. 29+65), where it confluences with the runoff from the southern portion of the proposed Neighborhood 1.2 developer improvements. The runoff from the Neighborhood 1.2 developer improvements drains towards a proposed desiltation basin and two proposed sump curb inlets, approximately located at the center of that portion of Street "A", before discharging south of the site. The peak discharge then drains naturally in a southerly direction towards the existing 0-34 headwall located at the northwest corner of the Poinsettia Lane- Alicante Road intersection, per Drawing No. 397-2F. Runoff from the proposed RV Storage site drains southerly towards a proposed curb outlet, which drains the discharge onto Street "A" towards a proposed on-grade curb inlet. The rest of the runoff from the proposed Neighborhood 1.3 mass-graded site drains southwesterly towards the aforementioned curb inlet, two proposed desiltation basins, and one existing desiltation basin, per Drawing No. 397-2Y. After confluencing, the runoff discharges southwest of the site via a 24-inch RCP storm drain system en route to the existing U-Type headwall located at approximate Sta. 23+00 off Poinsettia Lane, per Drawing No. 397-2H. From that point on, the discharge will follow the path described in the above "Existing Condition" section of this report. Best Management Practices (BMPs) have been recommended for this project site per the "Storm Water Management Plan (SWMP) for La Costa Greens Neighborhoods 1.2 & 1.3 Developer Improvements" prepared by Hunsaker & Associates and dated May 2006. As mentioned in the SWMP, one FloGard curb inlet filter unit (or approved equivalent), one COS treatment unit (or approved equivalent) and one grassy swale have been recommended to treat the 85th percentile flow. Also, pollutants in the form of silt generated by the mass-graded pads will be treated via the three desiltation basins on site, thus no further treatment will be required. 1.5 -Summary of Results Existing condition peak f10wrates were obtained form the "Mass-Graded Hydrology Study for La Costa Greens Neighborhoods 1.1-1.3 & EI Camino Real Widening" prepared by Hunsaker & Associates and dated August 2005 (see Appendix 8.1). The hydrologic analysis prepared for the proposed developer improvements for La Costa Greens Neighborhoods 1.2 & 1.3 project site in this study uses the City of Carlsbad methodology concurrent with the 2003 San Diego County Hydrology Manual methodology. For the developed condition rational method analySis, a runoff coefficient of 0.87 was used for future commercial areas, and a runoff coefficient of 0.71 was used for future multi-family residential areas, corresponding to 24.0 DUlac, and a runoff coefficient of 0.90 was used for paved streets, corresponding to areas that are 100% impeNious. For the mass-graded condition rational method analysis AH:ad H:\REPORTSI235Z\146\AOZ.doc W.O.2352·1461170 812112006 8:23 AM I I I I I I I I I I I I I I I I i I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 used to size the riser and desiltation basins, a runoff coefficient of 0.55 was used. All runoff coefficients are based on the 2003 San Diego County Hydrology Manual. Existing and developed condition peak flowrates, listed on Table 1 below, are based on the AES-2003 computer program and the City of Carlsbad Drainage Design Criteria (see Chapter 2 for methodology and model development and Chapter 3 for the AES model output). Watershed delineations and node locations are visually depicted on Exhibit 9.1, which is located in the back pocket of this report (see Chapter 9). TABLE 1. Existing and Developed Condition Hydrologic Results ---------Existing Conditions Developed Conditions Basin Node A Q Tc A Q Tc ID ID (ac) (cfs) (min) (ac) (cfs) (min) Basin 1* 120 1.5 6.3 6.1 2.4 10.8 5.3 Basin 2** 204 5.7 20.1 14.6 5.3 10.9 6.3 Total 7.2 26.4 NIA 7.7 21.7 NIA * BaSin 1 corresponds to the southern portion Neighborhood 1.2 (south of the Vida Roble cul-de-sac) ** Basin 2 corresponds to Neighborhood 1.3 As depicted in Table 1 above, development of the project site increases runoff in Basin 1 and decreases runoff in Basin 2, when compared to the existing condition peak flowrates. In Basin 1, the peak runoff increased by 4.5-cfs and in Basin 2 it decreased by 9.2-cfs. The increment in runoff in Basin 1 is partially attributed to the fact that the area increased slightly, since in its current mass-graded state 0.9-ac drained towards Neighborhood 1.1 and the Northern portion of Neighborhood 1.2, but now drains towards the southern portion of Neighborhood 1.2. The increment in runoff in Basin 1 does not affect the existing Alicante Detention Basin since in its entirety the overall peak discharge decreased by 4.7-cfs, or 17.8%. In addition; the Alicante Detention Basin has been appropriately sized to convey all runoff draining into it based on the "Master Detention Study for La Costa Greens" prepared by Hunsaker & Associates and dated August 2003. The "Drainage Study for A licante Road -North of Poinsettia" prepared by Hunsaker and Associates and dated December 2003 conservatively estimated apeak discharge of 154.2-cfs at the existing D-34 headwall located at the northwest corner of the Poinsettia Lane-Alicante Road intersection (see Appendix 8:2 and Exhibit 9.2 - Site Exhibit). The study also d.etermined that the existing D-34 headwall and existing storm drain system are both capable of handling the 154.2-cfs (see Appendix 8.3). A more accurate study, "Mass-Graded Hydrology Study for La Costa Greens Neighborhoods 1.1-1.3 & EI Camino Real Widening" prepared by Hunsaker & Associates and dated August 2005, later determined that the peak discharge at the same location actually equates to 143.3-cfs (see Appendix 8.1). Including the 4.5-cfs increment from Basin 1, at the existing headwall, the peak flowrate increases AH:ad H:IREPORTS123521146\A02.doc W.O.2352·146/170 8121/2006 8'23 AM I I I I I I I I -I I I I I I I I I I 'I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 from 143.3-cfs to 147.8-cfs, which is still well below the 154.2-cfs. In this study, both the existing D-34 headwall and the existing system were reanalyzed taking into account the increased peak discharge of 147.8-cfs to ensure that they are in fact capable of conveying said discharge (see Appendix 8.4). A headwater depth calculation with inlet control was determined using the nomograph for inlet control based on head available in order to ensure that the increased discharge of 147.8-cfs will not overflow onto Poinsettia Lane or Alicante Road (see Appendix 8.4). For the hydraulic portion of this report, all proposed storm drain systems were analyzed with the StormCAD software. Using a starting downstream water surface elevation at the discharge locations, the program calculated the hyqraulic grade line for the RCP storm drain systems (see Chapter 4 for StormCAD model outputs). All curb inlets have been sized to ensure that they are capable of handling 1 ~O-year developed condition peak flows (see Chapter 5). The same design criteria for on- grade curb inlet opening sizing specified by the City of Carlsbad was used to determine the opening length along the AC berm on Street "A", at approximate Sta. 14+58 (see Chapter 6). Finally, two proposed desilt basins were designed per Part 8 of Section A of the State Water Resources Control Board Order No. 99-08-DWQ, Option 2. One existing desilt basin was reviewed to ensure that it still functioned appropriately with - the new discharge draining into it. The mass-graded condition rational method analysis for riser and desilt basin design uses a runoff coefficient of 0.55, rather than the ultimate coefficients, in order to avoid oversizing the riser (see Chapter 7 for the AES model output and riser and desilt basin design). 1.6 -Conclusion Based on the calculations completed herein, the storm drain systems shall be able to function as designed and handle the flows generated from the La Costa Greens Neighborhoods 1.2 & 1.3 site. Drainage design, including watershed delineation and storm drain sizing, shall result in no adverse impact to downstream property owners. Construction of the storm drain improvements as shown herein should safely collect and convey peak discharge through the development. AH:ad H:IREPORTSI23521146\A02.doc W.O.2352-1461170 8121/200~ 8:23 AM I I I I I I I I I I I I' I I I I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 1.7 -References "San Diego County Hydrology Manual"; Department of Public Works -Flood Control Division; County of San Diego, California; Revised June 2003. "City of San Diego Regional Standard Drawings"; Section D -Drainage Systems; Updated March 2000. "City of Carlsbad Engineering Standards"; City of Carlsbad, California; June 2004. "Mass-Graded Hydrology Study for La Costa Greens Neighborhoods 1.1-1.3 & EI Camino Real Widening"; Hunsaker & Associates San Diego, Inc.; August 23, 2003. "Drainage Study for Alicante Road -North of Poinsettia Lane"; Hunsaker & Associates San Diego, Inc.; December 1,2003. "Storm Water Management Plan (SWMP) for Developer Improvements La Costa Greens Neighborhood 1.2 & 1.3"; Hunsaker & Associates San Diego, 'Inc.; April 13, 2005. "Master Detention Study for La Costa Greens"; Hunsaker & Associates San Diego, Inc.; August 2003. Drawing No. 397 -2F "Improvement Plans for La Costa Greens Alicante Road (North)", Sheets 9-11; Hunsaker & Associates San Diego, Inc.; January 16, 2003. Drawing No. 397 -2H "Grading and Drainage Plans for Poinsettia Lane at La Costa Greens"; Kimley-Horn & Associates, Inc.; January 16, 2003. Drawing No. 397-2Y "Grading & Erosion Control Plans for La Costa Greens Neighborhoods 1.01-1.03", Hunsaker & Associates San Diego, Inc.; November 23, 2005. Drawing No. 397-2D "La Costa Greens -Alicante Road (South)", Hunsaker & Associates San Diego, Inc.; January 24,2003. AH:ad H:IREPORTS\23521146\A02,doc W,O.2352-1461179 6121/2006 6:23 AM ! I I I I I' I I . I I I I' I I- I I I I' I 'I I I I I I I I I I I I I I I I I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPMiE,NT 2.1 • City of Carlsbad Engineering Standards AH:ad H:IREPORTS\235211461A02.dac W.O 2352-1461170 8121/2006 '8:23 AM I I I I I I I I I I I I I I I I I I, I CHAPTER 5-DRAINAGE AND STORM DRAIN STANDARDS 1. GENERAL A All drainage design and requirements shall be in accordance with the latest City of Carlsbad Standard Urban Storm Water Mitigation Plan (SUSMP), Jurisdictional Urban Runoff Management Plan' (JURMP), Master Drainage and Storm Water Quality Management Plan and the requirements of the City Engineer and be based on full development of upstream tributary basins. , ' B. Public drainage facilities shall be designed to carry the ten-year six-hour storm underground and the 100-year six-hour storm between, the top of curbs. All culverts shall be designed to accommodate a 1 OO-year six-hour storm with a one foot freeboard at entry conditions such as inlets and head walls. C. The use of underground storm drain systems, in addition to standard curb and' gutter shall be required: 1) When flooding or street overflow during 1 DO-year six-hour storm cannot be maintained between the top of curbs. 2) When 100-year six-hour storm flow from future upstream development (as proposed in the existing General Plan) will cause damage to structures and improvements. ' 3) When existing adequate drainage facilities are available for use (adjacent to proposed development). 4) When more than one travel lane of arterial and collector streets would be obstructed by 10-year 6-hour storm water flow. Special consideration will be required for super-elevated streets. D. The use of underground st~rm drain systems may be re,quired: 1) When the water level in streets at the design storm is within 1" of top of curb. 2) When velocity of water in streets exceeds 11 FPS. 3) When the water travels on surface street improvements for more than 1,000'. E. The type of drainage facility shall be selected on the basis of physical and cultural adaptability to the proposed land use. Open channels may be considered 'in lieu of underground systems when the peak flow exceeds the capacity of a 48" diameter RCP. Fencing of open channels may be required as determined by the City Engineer. F. Permanent drainage facilities and right-of-way, including access, shall be provided from development to point of approved disposal. Page 1 of 5 I I I I I I I I I I I I I I I I I I I 2. G Storm Drains constructed at a depth of 15' or greater measured from finish grade t.o the top of pipe or structure shall be considered deep storm drains and should be avoided if at all possible. When required, special design consideration will be required to the satisfaction of the City Engineer. Factors considered in the design will include: 1) Oversized specially designed access holes/air shafts 2) Line encasements 3) Oversizing lines 4) Increased easement requirement~ for maintenance access 5) Water-tight joints 6) Additional thickness of storm drain The project designer should meet with the planchecker prior to initiation of design to review design parameters. H, Concentrated drainage from lots or areas greater than 0.5 acres shall not be' discharged to City streets unless specifically approved by the City Engineer. /. Diversion of drainage from natural or existing basins is discouraged. J. Drainage design shall, comply with the City's Jurisdictional Urban Runoff Management Plan (JURMP) and requirements of the National Pollutant Discharge Elimination System (NPDES) permit. HYDROLOGY A Off site, use a copy of the latest edition City 400-scale topographic mapping. Show existing culverts, cross-gutters and drainage courses based on field review. Indicate the direction of flow; clearly delineate each drainage basin showing the area and discharge and the point of concentration. B. On site, use the grading plan. If grading is not proposed, then use a 100-scale plan or greater enlargement. Show all proposed and existing drainage facilities and drainage courses. Indicate the direction of flow. Clearly delineate each drainage basin showing the area and discharge and the point of concentration. C. Use the charts in the San Diego County Hydrology Manual for finding the "Te" and "I": For small areas, a five minute "Te" may be utilized with prior approval of the City Engineer. D. Use the existing or ultimate development, whichever gives the highest "C" factor. E. Use the rational formula Q = CIA for watersheds less than 0.5 square mile unless an alternate method is approved by the City Engineer. For watersheds in excess of 0.5 s::juare mile, the method of analysis shall be approved by the City Engineer prior to submitting calculations. . Page 20f 5 I I I I I I I I I I I I I I I I I I 3. HYDRAULICS 4. A Street -provide: 1) Depth of gutter flow calculation. 2) Inlet calculations. 3) Show gutter flow Q, inlet Q, and bypass Q on a plan of the street. B. Storm Drain Pipes and Open Channels -provide: 1) 2) 3) 4) 5) 6) INLETS Hydraulic loss calculations for: entrance, friction, junction, access hbles, bends, angles, reduction and enlargement. Analyze existing conditions upstream and downstream from proposed system, to be determined by 'the City Engineer on a case-by-case basis. Calculate critical depth and normal depth for open channel flow conditions. Design for non-silting' velocity of.2 FPS in a two-year frequency storm unless otherwise approved by the City Engineer. All pipes and outlets shall show HGL, velocity and Q value(s) for' design ~~. . Confluence angles shall be maintained between 45° and 90° from the main upstream flow. Flows shall not oppose main line flows. A Curb inlets at a sump condition should be designated for two CFS per lineal foot of opening when headwater may rise to the top of curb. , B. Curb inlets on a continuous grade should be designed based on the following . equation: C. D. Q = 0.7 L (a + y)3/2 Where: y = depth of flow in approach gutter in feet a = depth of depression of flow line at inlet in feet L = length of clear opening in feet (maximum 30 feet) Q = flow in CFS, use 1 DO-year design storm minimum Grated inlets should be avoided. When necessary, the design should be based on the Bureau of Public Roads Nomographs (now known as the Federal Highway Administration). All grated inlets shall be bicycle proof. All catch basins shall have an access hole in the top unless access through the grate section satisfactory to the City Engineer is provided. Page 3 of 5 I I I I '1 I I -I I I I I I I I I I II I 5. E. Catch basins/curb inlets shaff be located so as to eliminate, whenever possible, cross gutters. Catch basins/curb inlets shaff not be located within 5' of any curb return or driveway. F. Minimum connector pipe for public drainage systems shall be 18": G Flow through inlets may be used when pipe size is 24" or less and open channel flow characteristics exist. STORM DRAINS A Minimum pipe slope shaff be .005 (.5%) unless otherwise approved by the City Engineer. B.. Minimum storm drain"within public right-of-way, size shaff be 18" diameter. C. Provide c1eanouts at 300' maximum spacing, at angle points and at breaks in grade greater than 1 %. For pipes 48" in diameter and larger,· a maximum spacing of 500' may be used. When the storm drain clean-out Type A dimension of 'V' less "Z" is greater than 18", a storm drain clean-out Type B shaff be used. D. The material for storm drains shaff be reinforced concrete pipe designed in conformance with San Diego County Flood Control District's design criteria, as modified by Carlsbad Standard Specifications. Corrugated steel pipe shall not be used. Plastic/rubber coffars shaff be prohibited. E. Horizontal curve design shaff conform to manufacturer recommended specifications. Vertical curves require prior approval from the City Engineer. F. The pipe invert elevations, slope, pipe profile line and hydraulic grade line for design flows shaff be delineated on the mylar of the improvement plans. Any utilities crossing the storm drain shaff also be delineated. The strength classification of any pipe shaff be shown on the plans. Minimum D-Ioad for RCP shaff be 1350 in all City streets or future rights-of-way. Minimum D-Ioad for depths less than 2', if allowed, shall be 2000 or greater. G For all drainage designs not covered in these Standards, the current San Diego County Hydrology and Design and Procedure Manuals shaff be used. H. For storm drain discharging into unprotected or natural channel, proper energy dissipation measures shall be installed to prevent damage to the channel or erosion. In cases of limited access or outlet velocities greater than 18 fps, a concrete energy dissipater per SDRS 0-41 will be required. Page 4 of 5 I I I I I I I I I I I I' I I I I I I I .1. J. K. L. M. N. O. P. The use of detention basins to even out storm peaks and reduce piping is permitted with substantiating engineering calculatio'n and proper maintenance agreements. Detention basins shall be fenced .. Desiltation measures for silt. caused by development shall be provided and cleaned regularly during the rainy season (October 1 to April 30) and after major rainfall as required by the City Engineer or his designated representative. Adequate storage capacity as determined by the City Engineer shall be maintained at all times. Protection of downstream or adjacent properties from incremental flows (caused by change from an undeveloped to a developed site) shall be provided. Such flows shall not be concentrated and directed across unprotected adjacent properties unless an easement and storm drains or channels to contain flows are provided. Unprotected downstream channels shall have erosion and grade control structures installed to prevent degradation, erosion, alteration or downcutting of the channel banks. Storm drain pipes designed for flow meeting or exceeding 20 feet per second will require additional cover over invert reinforcing steel as approved by the City Engineer. Storm drain pipe under pressure flow for the design storm, i.e., HGL above the. soffit of the ppe, shall meet the requirements of ASTM C7e, C361, C443 for water-tight joints in the sections of pipe calculated to be under pressure and an additional safety length beyond the pressure flow point. Such sC!fety length shall be determined to the satisfaction of the City Engineer taking into consideration such factors as pipe diameter, Q, and velocity. . An all weather access road from a paved public right-of-way shall be constructed to all drainage and utility improvements. The following design parameters are required: Maximum grade 14%, 15 MPH speed, gated entry, minimum paved width 12 feet, 38' minimum radius, paving shall be a minimum of 4" AC over 4" Class" AS, turnaround required if over 300'. Work areas should be provided as approved by the plan checker. Access roads should be shoWn on the tentative project ·approval to ensure adequate environmental review. Engineers are encouraged to gravity drain all lots to the street without use of a yard drain system. On projects with new street improvements proposed, a curb outlet per SDRSD 0-27 shall be provided for single-family residential lots to allow yard drains to connect to the streets gutter. . Page 5 of 5 I I I I I I I I I I I I I I I I II I I CHAPTER 2 CITY OF CARLSBAD MODIFICATIONS TO THE SAN DIEGO REGIONAL STANDARD DRAWINGS Note: The minimum allowable concrete mix design for all concrete placed within public right- of-way shall be 560-C-3250 as specified in the Standard Specifications for Public Works Construction. DWG. MODIFICATION 0-2 Enlarge curb inlet top to width of sidewalk (not to exceed 5'6") by length of inlet including wings. Existing reinforcing steel shall be extended across enlarged top to clear distances shown. - 0-20 Delete. 0-27 0-40 0-70 0-71 0-75 E-1 E-2 G-3 G-5 G-6 G-11 Add: A maximum of three (3) combined outlets in lieu of Std. 0-25. Add: "T" dimension shall be a minimum of three (3) times size of rip rap. Minimum bottom width shall be 6' to facilitate cleaning. Minimum bottom width shall be 6' to facilitate cleaning. Delete "Type-A" Add: 6" x 6" x #10 x #10 welded wire mesh, instead of stucco netting. Delete direct burial foundation. Add: The light standard shall be pre-stressed concrete round pole. Grounding per note 2. Attachment of the grounding wire to the anchor bolt shall be below the light standard base plate with an approved connection. Delete. Add: Note 4. Tack coat shall be applied between dike and existing asphalt concrete surface as specified in Section 302-5.4 SSPWC. Type 8-1 not used. When specified, Type 8-2 shall have a curb height ofe", width of 6", with a 3: 1 batter. When specifically approved by the City Engineer, Type 8-3 shall have a curb height of 8", width of 6", a 3:1 batter with the hinge point eliminated. Add: Remove curb/gutter and sidewalk from score-mark to score-mark or from joint-to-joint or approved combination. 1 I I I I I I I I I I I I I I I I I I II DWG. G-12 G-13 G-14 G-15 G-24 G-25 G-26 G-33 G-34 G-35 M M-2 CITY OF CARLSBAD MODIFICATIONS TO THE SAN DIEGO REGIONALSTANDARD DRAWINGS MODIFICATION Add: smooth trowel flow line (typical) 7-1/2" thick with a minimum of 6" of aggregate base per City of Carlsbad Standard GS-17. Add: smooth trowel flow line (typical), 7-1/2" thick, with a minimum 6" of aggregate base per City of Carlsbad Standard GS-17. Change: Residential Thickness = 5-1/2" Commercial/Multi-Family Residential Thickness = 7-1/2" Delete requirement 3 ''Type-A'' only (delete "Type B") "Type-C" only (delete "Type 0") Change thickness from 5-1/2" to 7-1/2" and add minimum 4" Class II base under curb/gutter (to 6" past back of curb). Delete "Type-C" only (delete "Type 0") "Type-F" only (delete "Type E") General: Agency shall be "City of Carlsbad" Add: To be used only with specific approval of the City Engineer. 2 I I I I I I I I I I I I I I I I I i I ! I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPME'NT 2.2 -County of San Diego Drainage Design Criteria AH:ad H:IREPORTSI235211461A02.doc W.O.2352·146/170 8/2112006 8:23 AM I I I I I I I I I I I I I I I I I I I San Diego County Hydrology Manual Date: June 2003 Section: Page: 2.3 SELECTION OF HYDROLOGIC METHOD AND DESIGN CRITERIA 2 30f4 Design Frequency -The flood frequency for determining the design storm discharge is 50 years for drainage that is upstream of any major roadway and 100 years frequency for all design storms at a major roadway, crossing the major roadway and thereafter. The 50-year storm flows shall be contained within the pipe and not encroach into the travel lane. For the IOO-year storm this includes allowing one lane of a four-lane road (four or more lanes) to be used for conveyance without encroaching onto private property outside the dedicated street right-of-way. Natural channels that remain natural within private property are excluded from the right-of-way guideline. Design Method -The choice of method to determine flows ( discharge) shall be based on the size of the watershed area. For an area 0 to approximately I square mile the Rational Method or the Modified Rational Method shall be used. For watershed areas larger than I square mile the NRCS hydrologic method shall be used. Please 'check with the governing agency for any variations to these guidelines. 2-3 I I I I I I I I I I I I I I I I. I I I San Diego County Hydrology Manual Date: June 2003 SECTION 3 Section: Page: RATIONAL METHOD AND MODIFIED RATIONAL METHOD 3.1 THERATIONALMETHOD 3 10f26 The Rational Method (RM) is a mathematical formula used to determine the ma)l:imum runoff rate from a given rainfall. It has particular application in urban storm drainage, where it is used to estimate peak runoff rates from small urban and rural watersheds for the design of storm drains and small drainage structures. The RM is recommended for analyzing the runoff response from drainage areas up to approximately 1 square mile in size. It should not be used in instances where there is a junction of independent drainage systems or for drainage areas greater than approximately 1 square mile in size. In these instances, the Modified Rational Method (MRM) should be used for junctions. of independent drainage systems in watersheds up to approximately 1 square mile in size (see Section 3.4); or the NRCS Hydrologic Method should be used for watersheds greater than approximately 1 square mile in size (see Section 4). The RM can be applied using any design storm frequency (e.g., IOO-year, 50-year, IO-year, etc.). The local agency determines the design storm frequency that must be used based on the type of project and specific local requirements. A discussion of design storm frequency is provided in Section 2.3 of this manual. A procedure has been d~veloped that converts the 6-hour and 24-hour precipitation isopluvial map data to an Intensity-Duration curve that can be used for the rainfall intensity in the RM formula as shown in· Figure 3-1. The RM is applicable to a 6-hour storm duration because the procedure uses Intensity-Duration Design Charts that are based on a 6-hour storm duration. 3.1.1 Rational Method Formula The RM formula estimates the peak rate of runoff at any location in a watershed as a function of the drainage area (A), runoff coefficient (C), and rainfall intensity (1) for a duration equal to the time of concentration (T c), which is the time required for water to 3-1 I I I I I I I I I I I I I I I I I I I San Diego County Hydrology Manual Date: June 2003 Section: Page: 3 30f26 flow from the most remote point of the basin to the location being analyzed. The RM formula is expressed as follows: Q=CIA Where: Q = peak discharge, in cubic feet per second (cfs) C = runoff coefficient, proportion of the rainfall that runs off the surface (no units) I = average rainfall intensity for a duration equal to the Te for the area, in inches per hour (Note: If the computed Te is less than 5 minutes, use 5 minutes for computing the peak discharge, Q) A = drainage area contributing to the design location, in acres Combining the units for the expression CIA yields: (lacreXinch) (43,560feJ ( Ifoot ) ( Ihour ) => l.OOS,cfs hour acre 12 inches 3,600 seconds For practical purposes the unit conversion coefficient difference of O.S% can be ignored .. The RM formula is based on the assumption that for constant rainfall intensity, the peak discharge rate at a point will occur when the raindrop that falls at the most upstream point in the tributary drainage basin arrives at the point of interest. Unlike the MRM (discuss.ed in Section 3.4) or the NRCS hydrologic method (qiscussed in Section 4), the RM does not create hydro graphs and therefore does not add separate subarea hydrogr:aphs at collection points. Instead, the RM develops peak discharges in the main line by increasing the Teas flow travels downstream. Characteristics of, or assumptions inherent to, the RM are listed below: • The discharge flow rate resulting from any I is maximum when the I la~ts as long as or longer than the Te. 3-3 I I I I I I I I I I I I I I I I I I I San Diego County Hydrology Manual Date: June 2003 Section: Page: • The storm frequency of peak discharges is the same as that ofI for the given Te. 3 4of26 • The fraction of rainfall that becomes runoff (or the runoff coefficient, C) is independent of I or precipitation zone number (PZN) condition (PZN Condition is discussed in Section 4.1.2.4). • The peak rate of runoff is the only information produced. by using the RM. 3.1.2 Runoff Coefficient Table 3-1 lists the estimated runoff coefficients for urban areas. The concepts related to the runoff coefficient were evaluated in a report entitled Evaluation, Rational Method "e" Values (Hill, 2002) that was reviewed by the Hydrology Manual Committee. The Report is available at San Diego County Department of Public Works, Flood Control Section and on the San Diego County Department of Public Works web page. The runoff coefficients are based on land use and soil type. Soil type can be determined from the soil type map provided in Appendix A. An appropriate runoff coefficient (C) for each type of land use in the subarea should be selected from this table and multiplied by the percentage of the total area (A) included in that class. The sum of the products for all land uses is the weighted runoff coefficient (L[CAD. Good engineering judgment should be used when applying the values presented in Table 3-1, as adjustments to these values may be appropriate based on site-specific characteristics. In any event, the impervious percentage (% Impervious) as given in the table, for any area, shall govern the selected value for C. The runoff coefficient can also be calculated for an area based on soil type and impervious percentage using the following formula: 3-4 I I I I I I I I I I I I I I I I I I !I San Diego County Hydrology Manual Section: Date: June 2003 Page: C = 0.90 x (% Impervious) + Cp x (1 -% Impervious) 3 50f26 Where: Cp = Pervious Coefficient Runoff Value for the soil type (shown in Table 3-1 as Undisturbed Natural TerrainlPermanent Open Space, 0% Impervious). Soil type cali be determined from the soil type map provided in Appendix A. The values in Table 3-1 are typical for most urban areas. However, if the basin contains rural or agricultural land use, parks, golf courses, or other types of nonurban land use that are expected to be permanent, the appropriate value should be selected based upon the soil and cover and approved by the local agency. 3-5 I I I I I I I I I I I I I I I I II I I I San Diego County Hydrology Manual Date: June 2003 3.1.3 Rainfall Intensity Section: Page: 3 7of26 The rainfall intensity (1) is the rainfall in inches per hour (in!hr) for a duration equal to the Tc for a selected storm frequency. Once a particular storm frequency has been selected for design and a Tc calculated for the drainage area, the rainfall intensity can be determined from the Intensity-Duration Design Chart (Figure 3-1). The 6-hour storm rainfall amount (P6) and the 24-hour storm rainfall amount (P24) for the selected storm frequency are also needed for calculation of I. P6 and P24 can be read from the'isopluvial maps provided in Appendix B. An Intensity-Duration Design Chart applicable to all areas within San Diego County is provided as Figure 3-1. Figure 3-2 provides an example of use of the Intensity-Duration Design Chart. Intensity can also be calculated using the following equation: 1= 7.44 P6 D-o.645 Where: P6 adjusted 6-hour storm rainfall amount (see discussion below) D = duration in minutes (use T c) Note: This equation applies only to the 6-hour storm rainfall amount (i.e., P6 cannot be changed to P24 to calculate a 24-hour intensity using this equation). The Intensity-Duration Design Chart and the equation are for the 6-hour storm rainfall amount. In general, P6 for the selected frequency should be between 45% and 65% ofP24 for the selected frequency. If P6 is not within 45% to 65% of P24, P6 should be increased or decreased as necessary to meet this criteria. The isopluvial lines are based on precipitation gauge data. At the time that the isopluvial lines were created, the majority of precipitation gauges in San Diego County were read daily, and these readings yielded 24-hour precipitation data. Some 6-hour data were available from the few recording gauges distributed throughout the County at that time; however, some 6-hour data were extrapolated. Therefore, the 24-hour precipitation data for San Diego County are considered to be more reliable. 3-7 ... ------------------------------------~------- I I I I I I I I, I I I· I I I I I I I I San Diego County Hydrology Manual Date: June 2003 3.1.4 Time of Concentration Section: Page: 3 .90f26 The Time of Concentration (T c) is the time required for runoff to flow from the most remote part of the drainage area to the point of interest. The Tc is composed of two components: initial time of concentration (Tj) and travel time (Tt}. Methods of computation for Tj and Tt are discussed below. The Tj is the time required for runoff to travel across the surface of the most remote subarea in the study, or "initial subarea." Guidelines for designating the initial subarea are provided within the discussion of computation of Tj. The Tt is the time required for the runoff to flow in a watercourse (e.g., swale, channel, gutter, pipe) or series of watercourses from the initial subarea to the point of interest. For the RM, the Tc at any point within the drainage area is given by: Methods of calculation differ for natural watersheds (nonurbanized) and for urban drainage systems. When analyzing storm drain systems, the designer must consider the possibility that an existing natural watershed may become urbanized during the useful life of the storm drain system. Future land uses must be used for T c and runoff calculations, and can be determined from the local Community General Plan. 3.1.4.1 Initial Time of Concentration The initial time of concentration is typically based on sheet flow at the upstream end of a drainage basin. The Overland Time of Flow (Figure 3-3) is approximated by an equation developed by the Federal Aviation Agency (FAA) for analyzing flow on runaways (FAA, 1970). The usual runway configuration consists of a crown, like most freeways, with sloping pavement that directs flow to either side of the runway. This type of flow is uniform in the direction perpendicular to the velocity and is very shallow. Since these depths are Y4 of an inch (more or less) in magnitude, the relative roughness is high. Some higher relative roughness values for overland flow are presented in Table 3.5 of the HEC-J Flood Hydrograph Package User's Manual (USACE, 1990). 3-9 I I I I I I I I I I I I I I I I I I I San Diego County Hydrology Manual Date: June 2003 Section: Page: 3 I1of26 The sheet flow that is predicted by the FAA equation is limited to conditions that are similar to runway topogrflphy. Some considerations that limit the extent to which the FAA equation applies are identified below: • Urban Areas -This "runway type" runoff includes: 1) Flat roofs, sloping at 1 % ± 2) Parking lots at the extreme upstream drainage basin boundary (at the "ridge" 0f a catchment area). Even a parking lot is limited in the amounts of sheet flow. Parked or moving vehicles would "break-up" the sheet flow, concentrating runoff into streams that are not characteristic of sheet flow. 3) Driveways are constructed at the upstream end of catchment areas in some developments. However, if flow from a roof is directed to a driveway through a downspout or other conveyance mechanism, flow would be concentrated. 4) Flat slopes are prone to meandering flow that tends to be disrupted by minor irregularities and obstructions. Maximum Overland Flow lengths are shorter . for the flatter slopes (see Table 3-2). • Rural or Natural Areas -The FAA equation is applicable to these conditions since (.5% to 10%) slopes that are uniform in width of flow have slow velocities consistent with the equation. Irregularities in terrain limit the length of application. 1) Most hills and ridge lines have a relatively flat area near the drainage divide. However, with flat slopes of .5% ±, minor irregularities would cause flow to concentrate into streams. 2) Parks, lawns and other vegetated areas would have slow velocities that are consistent with the FAA Equation. The concepts related to the initial time of concentration were evaluated in a report entitled Initial Time of Concentration, AnalysiS of Parameters (Hill, 2002) that was reviewed by the Hydrology Manual Committee. The Report is available at San Diego County Department of Public Works, Flood Control Section and on the San Diego County Department of Public Works web page. 3-11 I I I I I I I I I· I I I I I I San Diego County Hydrology Manual Date: June 2003 Section: Page: 3 120f26 Note that the Initial Time of Concentration should be reflective of the general land-use at the upstream end of a drainage basin. A single lot with an area of two or less acres does not have a significant effect where the drainage basin area is 20 to 600 acres. Table 3-2 provides limits of the length (Maximum Length (LM» of sheet flow to be used in hydrology studies. Initial Ti values based on average C values for the Land Use Element are also included. These values can be used in planning and design applications as described below. Exceptions may be approved by the "Regulating Agency" when submitted with a detailed study. Table 3-2 MAXIMUM OVERLAND FLOW LENGTH (LM) & INITIAL TIME OF CONCENTRATION (Ti) Element* DU/ .5% 1% 2% 3% 5% 10% Acre LM Ti LM Ti LM Ti LM Ti LM T .1 LM Ti Natural 50 13.2 70 12.5 85 10.9 100 10.3 100 8,7 100 6.9 LDR 1 50 12.2 70 11.5 85 10.0 100 9.5 100 8.0 100 6.4 LDR 2 50 11.3 70 10.5 85 9.2 100 8.8 100-7.4 100 5.8 LDR 2.9 50 10.7 70 10.0 85 8.8 95 8.1 100 7.0 100 5.6 MDR 4.3 50 10.2 70 9.6 80 8.1 95 7.8 100 6.7 100 5.3 MDR 7.3 50 9.2 65 8.4 80 7.4 95 7.0 100 6.0 100 4.8 MDR 10.9 50 8.7 65 7.9 80 6.9 90 6.4 100 5.7 100 4.5 MDR 14.5 50 8.2 65 7.4 -80 6.5 90 6.0 100 5.4 100 4.3 HDR 24 50 6.7 65 6.1 75 5.1 90 4.9. 95 4.3 100 3.5 HDR 43 50 5.3 65 4.7 75 4.0 85 3.8 95 3.4 100 2.7 N.Com 50 5.3 60 4.5 75 4.0 85 3.8 95 3.4 100 2.7 G.Com 50 4.7 60 4.1 75 3.6 85 3.4 90 2.9 100 2.4 O.P.lCom 50 4.2 60 3.7 ·70 3.1 80 2.9 90 2.6 100 2.2 Limited 1. 50 4.2 60 3.7 70 3.1 80 2.9 90 2.6 10Q 2.2 General 1. 50 3.7 60 3.2 70 2.7 80 2.6 90 2.3 100 1.9 *See Table 3-1 for more detailed description 3-12 I I I I I, I I I I I I I I I I I I I I San Diego County Hydrology Manual Date: June 2003 3.1.4.1A Planning Considerations Section: Page: 3 130f26 The purpose of most hydrology studies is to develop flood flow values for areas that are not at the upstream end of the basin. Another example is the Master Plan, which is usually completed before the actual detailed design of lots, streets, etc. are accomplished. In these situations it is necessary that the initial time of concentration be determined without detailed information about flow patterns. To provide guidance for the initial time of concentration design parameters, Table 3-2 includes the Land Use Elements and other variables related to the Time of Concentration. The table development included a review of the typical "layout" of the different Land"Use Elements and related flow patterns and consideration of the extent of the sheet flow regimen, the effect of ponding, the significance to the drainage basin, downstream effects, etc. 3.1.4.1B Computation Criteria (a) Developed Drainage Areas With Overland Flow -Ti may be obtained directly from the chart, "Rational Formula -Overland Time of Flow Nomograph," shown in Figure 3-3 or from Table 3-2. This chart is based on the Federal Aviation Agency (FAA) equation (FAA, 1970). For the short rain durations «15 minutes) involved, intensities are high but the depth of flooding is limited and much of the runoff is stored temporarily in the overland flow and in shallow ponded areas. In developed areas, overland flow is limited to lengths given in Table 3-2. Beyond these distances, flow tends to become concentrated into streets, gutters, swales, ditches, etc. 3-13 I I I I I I I' I I I I I I I I I I I I San Diego County Hydrology Manual Date: June 2003 Section: Page: 3 140f26 (b) Natural Or Rural Watersheds -These areas usually have an initial subarea at the upstream end with sheet flow. The sheet flow length is limited to 50 to 100 feet as specified in Table 3-2. The Overland Time of Flow Nomograph, Figure 3-3, can be used to obtain Tj. The initial time of concentration can excessively affect the magnitude of flow further downstream in the drainage basin. For instance, variations in the initial time of concentration for an initial subarea of one acre can change the flow further downstream where the area' is 400 acres by 100%. Therefore, the initial time of concentration is limited (see Table 3-2). The Rational Method procedure included in the original Hydrology Manual (1971) and Design and Procedure Manual (1968) included a 10 minute value to be added to the initial time of concentration developed through the Kirpich Formula (see Figure 3-4) for a natural watershed. That procedure is superceded by the procedure above to use Table 3-2 or Figure 3-3 to determine Tj for the appropriate sheet flow length of the initial subarea. The values for natural watersheds given in Table 3-2 vary from 13 to 7 minutes, depending on slope. If the total length of the initial subarea is greater than the maximum length allowable based on Table 3-2, add the travel time based on the Kirpich formula for the remaining length of the initial subarea. 3.1.4.2 Travel Time The Tt is the time required for the runoff to flow in a watercourse (e.g., swale, channel? gutter, pipe) or series of watercourses from the initial subarea to the point of interest. The Tt is computed by dividing the length of.the flow path by the computed flow velocity. Since the velocity normally changes as a result of each change in flow rate or slope, such as at an inlet or grade break, the total Tt must be computed as the sum of the Tt's for each section of the flow path. Use Figure 3-6 to estimate time of travel for street gutter flow. Velocity in a channel can be estimated by using the nomograph shown in Figure 3-7 (Manning's Equation Nomograph). 3-14 I I I I I I I: I I I~ I I I I'" I I I I I San Diego County Hydrology Manual Date: June 2003 Section: Page: 3 150f26 (a) Natural Watersheds -This includes rural, ranch, and agricultural areas with natural channels. Obtain Tt directly from the Kirpich nomograph in Figure 3-4 or from the equation. This nomograph requires values for length and change in elevation along the effective slope line for the subarea. See Figure 3-5 for a representation of the effective slope line. This nomograph is based on the Kirpich formula, which was developed with data from agricultural watersheds ranging from 1.25 to 112 acres in area, 350 to 4,000 feet in length, and 2.7 to 8.8% slope (Kirpich, 1940). A maximum length of 4,000 feet should be used for the subarea length. Typically, as the flow length increases, the depth of flow will increase, and therefore' it is considered a concentration of flow at points beyond lengths listed in Figure 3-2. However, because the Kirpich formula has been shown to be applicable for watersheds up to 4,000 feet in length (Kirpich, 1940), a subarea may be designated with a length up to 4,000 feet provided the topography and slope of the natural channel are generally unifoI111. Justification needs to be included with this calculation showing that the watershed will remain natural forever. Examples include areas located in the Multiple Species Conservation Plan (MSCP), areas designated as open space or rural in a community's General Plan, and Cleveland National Forest. (b) Urban Watersheds -Flow through a closed conduit where no additional flow can enter the system during the travel, length, velocity and Tt are determined using the peak flow in the conduit. In cases where the conduit is not closed and additional flow from a contributing subarea is added to the total flow during travel (e.g., street flow in a gutter), calculation of velocity and Tt is performed using -an assumed average flow based on the total area (including upstream subareas) contributing to the point of interest. The Manning equation is usually used to determine velocity .. Discharges for small watersheds typically range from 2 to 3 cfs per acre, depending on land use, drainage area, and slope and rainfall intensity. Note: The MRM should be used to calculate the peak discharge when there is a junction from independent subareas into the drainage system. 3-15 I; I I I I I I I I I I I I I I I I I :1 Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPME·NT 2.3 -Design Rainfall Determination 100-Year, 6-Hour Rainfaliisopluyial Map AH:ad H:IREPORTS123521146\A02,doc W.O.2352·1461.170 6/2112006 8:23 AM I I I I I I I I I I I I L + __ =-__ :_'_' I T- ;-.. + ... -1 ..... i3~4&''''''' : . :',., : I , -..---I.-... t--:.. --,- ~---.~-~ .~.-- I , I I I I County of San Diego Hydrology Manual Rainfall Isopluvials 1 00 Year Rainfall Event - 6 Hours Iso pluvial (inches) = 2.? I~ THIS MAP IS PROVIDED WITHOUT WARRANiY OF ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FJTJNESS FORA PARTICULAR PURPOSE. COpyrl~ht SanG)S. All Rights Reserved. This products may contain In(ormatlon from the SANDAG Regional (n(onnation System which cannot be reproduced WIthout the written pennission of SANDAG. This product may contatn Info~ation which has been reproduced with pel'TTlission granted by Thomas Brothers M~ps. Miles I I I I I I I I I I I I I I '1 I. I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPMENT . 2.3 -Design Rainfall Determination 100-Year, 24-Hour Rainfall Isopluvial Map AH:ad H:\REPORTS\23521146IA02.doc W.O.2352·1461170 8/21/2006 8:23 AM I ,I I I ,I I I 1:1-", ,-,-, --;-;-- ! , -;--,-iii! :--t;, .. ; : :!. ·i I ! 0, I i co l I ~ I! 1 " . I _.i .. ' ' , ' ,,-,.-' I '--" i'..L~, i : L ,--;- i -r-:--I i._-;-\-, I ! I i-:-r i j ; ; --~ L; : I " ~'I '....L+.. 1 _'-'--'-I I 1-'-' ; 1 ••• !! ' , I i ! . i ! ! I i 1 ~;i~fT~; ,jt:~ \:-:-ItCL!L~.'~~~NrY. I : ' :---i i--.-. I I ;-D .. :-:lJi.L i !--.-:, 1- I ---_. I , i __ -; _; ~i.; -~-n ~'-~~~-i : ~~-t~-i : ~-- _ _~ .. i f ...1_1 __ . , .-L! :. ___ 1_' '_'_1. ... L-L_' l--i--; ;---'~:.. \ '--i-- ""-32~45~ -_OJ -' -'-i ! i i ~ .-! : ; _: ---L_! !-j . --;--+-: --;----'1 I -+-I --,-,-,-, ----,.': i. 0'" I tn I' " 'I :U' ,: ~I " -', (I); . ,,' :J.~. ,~~-=-4L~,1= ,'T-. \i h' , , I,: c: : :, I: : ::::II . J ~-, ~;Cr<~t?jQl[I~ ! ,.' .~.<, ; -N; i : : Tl '.1'<: :;t i '; If , ; , 1_: .~ j 1 Q.. t. ; I County of San Diego , Hydrology Manual Rainfall Isopluvials Isopluvial (inches) ?/oO,24 == S. D / NC#8"r \~ \. / ~'.. 1\: E45 :! "\ f': i "'", I-~r----'-'1----------------------------------'. .... _ .. ' , :"" ! .... , ;' 1 :. .'-.... i " .. ~ ; .. ~ : I ,r-;;-:-&~ !; , '. ~.:~ ; ~ ;.~.~~ .~~~~ : l_~ __ _ I : : ; ; , • ! i: i I : i I Ii, I! i j : ; ; i I \! ~-j . I ' I I i i l_tJ.tbe X, itl .0 ; . ; : ,: '..L'::; t-itS~~~itW+ ;~~ .. :-:-;+:. ~i .:.;~! ~+~~:p}-~ I ~~-7~---~ I I , I DPW ~GIS Ga~=::::f!~~~m N +E S 303 ~ THIS MAP IS PROVIDED WITHOUT WARRANIY OF ANY KIND, EITHER EXPRESS OR IMPUED, INCLUDING, BUT NOT UMlTED TO, THE IMPUED WARRANTIES OF MERCHANTABILITY AND FITNESS FORA PARTICULAR PURPOSE. Copyright SanGIS. AU Rights Reserved. This products may contain Infannation from the SANDAG Regional Infannation System which cannot be reproduced without the written permission of SANDAG. thIS product may contain infonnatlon which has been reproduced with permission granted by Thomas Brothers Maps. Miles I I I I I I I I I I I I I I I I I ! I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPMENT 2.4 -Rainfall Coefficient Determination AH:ad H:IREPORTSI235211461A02.doc W.O.2352·1461170 6121/2006 8:23 AM ----------- ---- San Diego County Hydrology Manual Date: June 2003 Table 3-1 Section: Page: RUNOFF COEFFICIENTS FOR URBAN AREAS Land Use Runoff Coefficient "C" Soil T~Ee NRCS Elements Coun Elements %IMPER. A B Undisturbed Natural Terrain (Natural) Permanent Open Space 0* 0.20 0.25 Low Density Residential (LDR) Residential, 1.0 DUiA or less 10 0.27 0.32 Low Density Residential (LDR) Residential, 2.0 DU/A or less 20 0.34 0.38 Low Density Residential (LDR) Residential, 2.9 DU/A or less 25 0.38 0.41 Medium Density Residential (l\t1DR) Residential, 4.3 DUiA or less 30 0.41 0.45 Medium Density Residential (l\t1DR) Residential, 7.3 DU/A or less 40 0.48 0.51 Medium Density Residential (l\t1DR) Residential, 10.9 DU/A or less 45 0.52 0.54 Medium Density Residential (l\t1DR) Residential, 14.5 DU/A or less 50 0.55 0.58 High Density Residential (HDR) Residential, 24.0 DU/A or less 65 0.66 0.67 High Density Residential (HDR) Residential, 43.0 DU/A or less 80 0.76 0.77 CommerciallIndustrial (N. Com) Neighborhood Commercial 80 0.76 0.77 CommerciallIndustrial (G. Com) General Commercial 85 0.80 0.80 CommerciallIndustrial (O.P. Com) Office Professional/Commercial 90 0.83 0.84 CommerciallIndustrial (Limited I.) Limited Industrial 90 0.83 0.84 CommerciallIndustrial (General I.) General Industrial 95 0.87 0.87 C 0.30 0.36 0.42 0.45 0.48 0.54 0.57 0.60 0.69 0.78 0.78 0.81 0.84 0.84 0.87 - --- 3 .6of26 D 0.35 0.41 0.46 0.49 0.52 0.57 0.60 0.63 0.71 0.79 0.79 0.82 0.85 0.85 0.87 *The values associated with 0% impervious may be used for direct calculation of the runoff coefficient as described in Section 3.1.2 (representing the pervious runoff coefficient, Cp, for the soil type), or for areas that will remain tindh;turbed in perpetuity. Justification must be given that the area will remain natural forever (e.g., the area is located in Cleveland National Forest). DU/A = dwelling units per acre NRCS = National Resources Conservation Service 3-6 I I I I I I I I I I I I I I I I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPME'NT 2.5 -Rainfall Intensity Determination Maximum Overland Flow Length & Initial Time of Concentratio'n Table AH:ad H:IREPORTS123521146\A02.doc W.O.2352-146/170 8/2112006 8:23 AM I I I I I I I I I I I I I I I II I I I San Diego County Hydrology Manual Date: June 2003 Section: Page: 3 12of26 Note that the Initial Time of Concentration should be reflective of the general land-use at the upstream end of a drainage basin. A single lot with an area of two or less acres does not have a significant effect where the drainage basin area is 20 to 600 acres. Table 3-2 provides limits of the length (Maximum Length (LM)) of sheet flow to be used in hydrology studies. Initial Ti values based on average C values for the Land Use Element are also included. These values can be used in planning and design applications as described below. Exceptions may be approved by the "Regulating Agency" when submitted with a detailed study. Table 3-2 MAXIMUM OVERLAND FLOW LENGTH (LM) & INITIAL TIME OF CONCENTRATION (Ti) Element* DU/ .5% 1% 2% 3% 5% 10% Acre LM Ti LM Ti LM Ti LM Ti LM Ti LM Ti Natural 50 13.2 70 12.5 85 10.9 100 10.3 100 '8.7 100 6.9 LDR 1 50 12.2 70 11.5 85 10.0 100 9.5 100 8.0 100 6.4 LDR 2 50 11.3 70 10.5 85 9.2 100 8.8 100 7.4 100 5.8 LDR 2.9 50 10.7 70 10.0 85 8.8 95 8.1 100 7.0 100 5.6 MDR 4.3 50 10.2 70 9.6 80 8.1 95 7.8 100 6.7 100 5.3 MDR 7.3 50 9.2 65 8.4 80 7.4 95 7.0 100 6.0 100 4.8 MDR 10.9 50 8.7 65 7.9 80 6.9 90 6.4 100 5.7 100 4.5 MDR 14.5 50 8.2 65 7.4 80 6.5 90 6,0 100 5.4 100 4.3 HDR 24 50 6.7 65 6.1 75 5.1 90 4.9 95 4.3 100 3.5 HDR 43 50 5.3 65 4.7 75 4.0 85 3.8 95 3.4 100 2.7 N.Com 50 5.3 60 4.5 75 4.0 85 3.8 95 3.4 100 2.7 G.Com 50 4.7 60 4.1 75 3.6 85 3.4 90 2.9 100 2.4 O.P.lCom 50 4.2 60 3.7 70 3.1 80 2.9 90 2.6 100 2.2 Limited I. 50 4.2 60 3.7 70 3.1 . 80 2.9 90 2.6 100 2.2 General I. 50 3.7 60 3.2 70 2.7 80 2.6 90 2.3 100 1.9 *See Table 3-1 for more detailed description 3-12 I I I I I I I I I I I I I I I I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPME'NT 2.5 -Rainfall Intensity Determination. Urban Watershed Overland Time of Flow Nomograph AH:ad H:IREPORTSI235211461A02.doc W.02352·1461170 6121/2006 8:23 AM - - - - -,-,-- --.----- - --- 1001 1.56/011.1 I} I vr .. :.-n ffi ~ ~ ill ~ ill Z LL 0 -Z ~ -Z ill -o ill Z ~ ~ ~ w ~ 5 9 lli c ::: ().9S ~ !5 -10 Z o ~ o ~ ~ ill ill > ~ 0 3: ~=--L-----J------~----~------~----~------~----~!O EXAMPLE: Given: Watercourse Distance (D) = 70 Feet Slope (s) =1.3% Runoff Coefficient (C) = 0.41 Overland Flow Time (T) = 9.5 Minutes T = 1.8 (i.1·C) Yo 3VS SOURCE: Airport Drainage. Federal Aviation Administration. 1965 FIGURE Rational Formula -Overland Time of Flow Nomograph 3·3· I I I I I I I I I I I I I I I I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELO·PMENT 2.5 -Rainfall Intensity Determination . Gutter & Roadway Discharge-Velocity Chart AH:ad H:IREPORTSI235211461A02.dpc W.O.2352·146/170 6/21/2006 6:23 AM I I I I I I I, I I I I I I I I I I I I 1~1,5'~1 I~n = .015~1.L-__ --2% + -n = .0175 --------~------~ 2% 2 EXAMPLE: Concrete Gutter Given: Q = 10 5 = 2.5% 3 4 Chart gives: Depth = 0.4, Velocity = 4.4 f.p.s. Paved 5 6 7 8 9 10 Discharge (C.F.S.) SOURCE: San Diego County Department of Special District Services Design Manual Gutter and Roadway Discharge· Velocity Chart RESIDENTIAL STREET ONE SIDE ONLY 20 30 40 50 I I I I I I I I I I I I I I I I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 2 , . METHODOLOGY & MODEL DEVELOPME'NT 2.5 -Rainfall Intensity Determinati,on Manning's Equation Nomograph ," AH:ad H:IREPORTS\235211461A02.doc W.O.2352·1461170 812112006 8:23 AM I I I I I I I I I I I I I I I I I I 'f o .E L-a> C- al ~ .!: UJ 0.. o ...J U) 0.3 0.2 0.15 0.10 0.09 0.08 0.07 0.06 0.05 . 0.001 0.0009 0.0008 0.0007 0.0006 0.0005 0.0004 0.0003 EQUATION: V = 1.49 R2/35"2 n 0.2 0.3 0.4 4 5 6 7 8 9 10 20 GENERAL SOLUTION SOURCE: US DOT, FHWA, HDS-3 (1961) Manning's Equation Nomograph 30 20 3 2 1.0 . 0.9 '0.8 0:7 0.6 .. 0.5 0.01 0.02 c;: 0.03 1: a> '0 ~ a> o .U en 0.04 U) UJ rO.05 z : :c (!) 0.06 :::l 0 0:: 0.07 "0.08 '0.09 0.10 I I I Ii I I I I , I I I I I 'I I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPME:NT 2.5 -Rainfall Intensity Determination Intensity-Duration Design Chart AH:ad H:IREPORTSI235211461A02.doc W.O,2352·146/170 8/2112006 8:23 AM -- 10.0 9.0 '8.0, 7.0 6.0 5.0 r... r... 4.0 'r... 3. 2. 'S o ~ g1. ;:0. :t:: ~o. ~o .5' 0.- 0: o. o. o o , , ) , I , i ; I I ! I- ~ " ~ l"- ~ "'r--. . .... I' '" " i' • " 1'-"' .... -' -..., r" ... I'"" r.,;, r-.. !'o., " '" i' " I .. r.. "" I'"" '" I' r... .. '" :-., l"-I'" I' I" I .. " r--. ... ~ " I" ~ I' :"'01- I .. '" r-.. '" "l"- I' I' - ,Ii 6 7 8 910 15 --,-,------ EQUATION 1 == 7.44 Ps 0-0.645 I == Intensity (in/hr) P 6 == 6-Hour Precipitation (in) o = Duration (min) ...." " " r.. :-.,"" I" " ~ I,"" ~ l"-I' "" I' ""i'ool' " i'oo .... ~ i'oo" " I' " ,... I"-~, " .... ~ I'''" ,... 1-,... " .... ,,~ I " " . I- ImUI 1111111 20 30 40 50 2 3 4 5 6 Minutes Duration Hours -'--- --- - ((l :t: g -. "U iii o 6.0 "9: 5.5 er 5.0 g' 4.55' '0 4.0 ~ 3.6 .!!!. 3.0 2.5 2.0 1.5 1.0 Directions for Application: (1) From precipitation maps determine 6 hr and 24 hr amounts for the selected frequency. These maps are included in the County Hydrology Manual (10, 50, and 100 yr maps included in the Design and Procedure Manual). (2) Adjust 6 hr precipitation (If necessary) so that it Is within the range of 45% to 65% of the 24 hr precipitation (not applicapJe to Desert). . (3) Plot 6 hr precipitation on the right side of the chart. (4) Draw a line through the point patallel to the plotted lines. (5) This line is the intensity-duration curve for the location being analyzed. Appllcatlon Form: (a) Selected frequency ___ year P (b) Ps = __ in., P24 = __ 'P 6 = %(2) 24 (c) Adjusted P6(2) = __ in. (d) 1x = __ min. (e) I = __ in.lhr . Note: This chart replaces the Intensity-Duration-Frequency curves used since 1965. Intensity-Duration Design Chart -Template rIG U u 1 3-1 .1 I I. I I I I I II '1 I I I I '1 I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPMENT" 2.6 -Rational Method Model Development Summary " AH:ad H:IREPORTSI2352\146\AO~.aOC W.O.2352·1461170 6121/2006. 8:23 AM I. I I I I I I I I I I I I I I I I· '1 :1 Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 2.6 ~ Rational Method Hydrology Analysis Computer Software Package -AES-2003 Design Storm - 1 OO-Year Return Interval Land Use -Mass-Graded (future commercial site and multi-family residential sites) Soil Type -Hydrologic soil group D was assumed for all areas. Group D soils have very slow infiltration rates when thoroughly wetted. Consisting chiefly of clay soils with a high swelling potential, soils with a high permanent water table, soils with clay pan or clay layer at or near the surface, and shallow soils over nearly impervious materials, Group D soils have a very slow rate of water transmission. Runoff Coefficient -In accordance with the County of San Diego standards, mass-graded areas (future commercial site) were assigned a rUr:loff coefficient of 0.87, mass-graded areas (future multi-family residential) were deSignated a runoff coefficient of 0.71, and paved streets corresponding to areas that are 90% impervious were assigned a runoff coefficient of 0.90. For riser design calculations, mass-graded areas were designated a runoff coefficient of 0.55. Method of Analysis -The Rational Method is the most widefy used hydrologic model for estimating peak runoff rates. Applied to small urban and semi-urban areas with drainage areas less than 0.5 square miles, the Rational Method relates storm rainfall intensity, a runoff coefficient, and drainage area to peak runoff rate. This relationship is expressed by the equation: Q = CIA, where: Q = The peak runoff rate in cubic feet per second at the point of analysis. C = A runoff coefficient representing the area -averaged ratio of runoff to rainfall intensity. I = The time-averaged rainfall intensity in inches per hour corresponding to the time of concentration. A = The drainage basin area in acres. To perform a node-link study, the total watershed area is divided into subareas which discharge at designated nodes .. The procedure for the subarea summation model is as follows: 1. Subdivide the watershed into an initial subarea (generally 1 lot) and subsequent subareas, which are generally less than 10 acres in size. Assign upstream and downstream node numbers to each subarea. 2. Estimate an initial T c by using the appropriate nomograph or overland flow velocity estimation. 3. Using the initial T c, determine the corresponding values of I. Then Q = C I A. AH:ad H:IREPORTSI2352\1461A02.doc W.O.2352-146/170 8/21/2006 8:23 AM I I I I I I I I I I I I I I I, I I I. I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 4. Using Q, estimate the travel time between this node and the next by Manning's equation as applied to the particular channel or conduit linking the two nodes. Then, repeat the calculation for Q based on the revised intensity (which is a function of the revised time of concentration) The nodes are joined together by links, which may be street gutter flows, drainage swales, drainage ditches, pipe flow, or various channel flows. The AES-99 computer subarea menu is as follows: SUBAREA HYDROLOGIC PROCESS 1. Confluence analysis at node. 2. Initial subarea analysis (including time of concentration calculation). 3. Pipeflow travel time (computer estimated). 4. Pipeflow travel time (user specified). 5. Trapezoidal channel travel time. 6·. Street flow analysis through subarea. 7. User -specified information at node. 8. Addition of subarea runoff to main line. 9. V-gutter ~ow through area. 10. Copy main stream data to memory bank 11. Confluence main stream data with a memory bank 12. Clear a memory bank At the confluence point of two or more basins, the following procedure is used to combine peak flow rates to account for differences in the basin's times of concentration. This adjustment is based on the assumption that each basin's hydrographs are triangular in shape. 1. If the collection streams have the same times of concentration, then the Q values are directly summed, Qp = Qa + Qb; T p = Ta = T b 2. If the collection streams have different times of concentration, the smaller of the tributary Q values may be adjusted as follows: a. The most frequent case is where the collection stream with the longer time of concentration has the larger Q. The smaller Q value is adjusted by the ratio of rainfall intensities. AH:ad H:IREPORTS123521146IA02.doc W.O.2352·1461170 812112006 8:23 AM I I I I I I I I I I I I I I i I I I' I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 b. In some cases, the collection stream with the shorter time of concentration has the larger Q. Then the smaller Q is adjusted by a ratio of the T values. AH:ad H:IREPORTS\235211461A02.doc W.O.2352·1461170 8121/2006 8:23 AM I I I I I I I I I I I I I I II I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 2 METHODOLOGY & MODEL DEVELOPME'NT 2.7 -Hydraulic Model Development Summary AH:ad H:IREPORTS\235211461A02.doc, W.O.2352-146/170 812112006 8:23 AM I I I I I I I I I I I I I I I I I II I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 2.7 -Storm Drain Hydraulic Analysis Computer Software -Storm CAD Design Storm -100-Year Return Interval Storm drain systems in this analysis were sized to prevent street flooding and to predict outlet velocities to receiving channels. The Storm CAD computer program, developed by Haested Methods, was used to predict hydraulic grade lines, pipe flow travel times, and velocities in the storm drain systems. Required input includes the peak f10wrate at each inlet, upstream and downstream inverts, pipe lengths, and rim elevations. Flow calculations are valid for both pressure and varied flow situations, including hydraulic jumps, backwater, and drawdown curves. The gravity network solution is solved using a numerical model that utilizes both the direct step and standard step gradually varied flow methods. Junction losses are modeled using the standard method, which calculates'structure headloss based on the structure's exit velocity (velocity at the upstream end of the downstream pipe). The exit velocity head is multiplied by a user-entered ·coefficient to determine the loss according to the following formula: Hs = K * Vo2 / 2g Where Hs = structure head loss (ft.) K = head loss coefficient Vo= exit pipe velocity (ft/s) G = gravitational acceleration (ft/s2) Typical headloss coefficients used for the standard method range from 0·.5 to·1.0 depending on the number of pipes meeting at the junction and the confluence angle. For a trunkline only with no bend at the junction, a head loss coefficient of 0.5 is selected. For three or more entrance lines confluencing at a junction, a value of 1.0 is selected. AH:ad H:IREPORTSI235211461A02.doc W.O.2352·1461170 8/2112006 8:23 AM I I I I I I I I I I I I I I I I I I Headloss Coefficients for Junctions These are typical head loss coefficients used in the standard method for estimating headloss through manholes and junctions. Type of Manhole Trunkline only with no bend at the junction Trunkline only with 45 degree bend at junction Trunkline only with 90 degree bend at junction Trunkline with one lateral Two roughly equivalent entrance lines with angle < 90 degrees between lines Two roughly equivalent entrance lines with angle> 90 degrees between lines Three or more entrance lines Related Information Headlosses Method Section Typical Headloss Coefficients Diagram Headloss Coefficient E()3 0.5 p 0.6 C? 0.8 Small 0.6 V Large 0.7 ~ 0.8 V 0.9 9 1.0 I ,' , ' I i 'I I il il. II i I i l _ il :1 ;1, tl' , ;~ I :1 :1 :1 ' I I I I I I I I I· I I I I I I I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1_2 & 1.3 CHAPTER 3 RATIONAL METHOD HYDROLOGIC ANALYSIS 100-Year Developed Condition AES Model OutP.ut AH:ad H:IREPORTS123521146\A02.doc W.O.2352-146/170 !lI2112006 8:23 AM I I I I I I I I I I I I I I I I I I I **************************************************************************** RATIONAL METHOD HYDROLOGY COMPUTER PROGRAM PACKAGE Reference: SAN DIEGO COUNTY FLOOD. CONTROL DISTRICT 2003,1985,1981 HYDROLOGY MANUAL (c) copyright 1982-2003 Advanced Engineering Software (aes) Ver. 1.5A Release Date: 01/01/2003 License ID 1239 Analysis prepared by: HUNSAKER & ASSOCIATES -SAN DIEGO 10179 Huennekens Street San Diego, Ca. 92121 (858) 558-4500 ************************** DESCRIPTION OF STUDY ************************** * LA COSTA GREENS -NEIGHBORHOODS 1.2 & 1.3 * * 100-YEAR DEVELOPED CONDITIONS HYDROLOGIC ANALYSIS * * W.O.# 2352-141 05/10/2006 PREPARED BY: AH * ************************************~************************************* FILE NAME: H:\AES2003\2352\141\INT100.DAT TIME/DATE OF STUDY: 10:43 05/15/2006 USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION: 2003 SAN DIEGO MANUAL CRITERIA USER SPECIFIED STORM EVENT(YEAR) = 100.00 6-HOUR DURATION PRECIPITATION (INCHES) = 2.800 SPECIFIED MINIMUM PIPE SIZE(INCH) = 18.00 SPECIFIED PERCENT OF GRADIENTS(DECIMAL) TO USE FOR FRICTION SLOPE = 0.90 SAN DIEGO HYDROLOGY MANUAL "C"-VALUES USED FOR RATIONAL METHOD NOTE: USE MODIFIED RATIONAL METHOD PROCEDURES FOR CONFLUENCE ANALYSIS *USER-DEFINED STREET-SECTIONS FOR COUPLED PIPEFLOW AND STREETFLOW MODEL* HALF-CROWN TO STREET-CROSSFALL: CURB GUTTER-GEOMETRIES: MANNING WIDTH CROSSFALL IN-/ OUT-/PARK-HEIGHT WIDTH LIP HIKE FACTOR NO. (FT) (FT) SIDE / SIDE/ WAY (FT) (FT) (FT) (FT) (n) 1 2 15.0 10.0 0.020/0.020/ 20.0 15.0 0.020/0.020/ --- GLOBAL STREET FLOW-DEPTH CONSTRAINTS: 1. Relative Flow-Depth = 0.00 FEET 0.50 0.50 1.50 0.0313 0.125 0.0150 1.50 0.0313 0.125 0.0150 as (Maximum Allowable Street Flow Depth) -(Top-of-Curb) 2. (Depth) * (Velocity) Constraint = 4.0 (FT*FT/S) *SIZE PIPE WITH A FLOW CAPACITY GREATER THAN OR EQUAL TO THE UPSTREAM TRIBUTARY PIPE.* +--------------------------------------------------------------------------+ I BEGIN ANALYSIS OF NEIGHBORHOOD 1.2 -FUTURE COMMERCIAL SITE I I (NODE SERIES 100) I I I +---------------------------------------------------------------------------+ **************************************************************************** FLOW PROCESS FROM NODE 101.00 TO NODE 102.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< '============================================================================ *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .8700 S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET} = 70.00 UPSTREAM ELEVATION(FEET} = 317.00 DOWNSTREAM ELEVATION(FEET) = 315.60 ELEVATION DIFFERENCE(FEET} = 1.40 SUBAREA OVERLAND TIME OF FLOW(MIN.} = 2.749 WARNING: INITIAL SUBAREA FLOW PATH LENGTH IS GREATER THAN THE MAXIMUM OVERLAND FLOW LENGTH = 70.00 (Reference: Table 3-1B of Hydrology Manual) THE MAXIMUM OVERLAND FLOW LENGTH IS USED IN Tc CALCULATION! 100 YEAR RAINFALL INTENSITY(INCH/HOUR} 7.377 NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINDTE. SUBAREA RUNOFF(CFS) 1.41 TOTAL AREA(ACRES) = 0.22 TOTAL RUNOFF(CFS) = 1.41 ****************************************************************************". FLOW PROCESS FROM NODE 102.00 TO NODE 103.00 IS CODE = 51 1 I I I I I I I I I I I I I I I I I »»>COMPUTE TRAPEZOIDAL CHANNEL FLOW««< »»>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT) ««< ELEVATION DATA: UPSTREAM (FEET) = 315.60 DOWNSTREAM (FEET) CHANNEL LENGTH THRU SUBAREA(FEET) = 122.20 CHANNEL SLOPE CHANNEL BASE(FEET) 0.00 "Z" FACTOR = 99.990 MANNING'S FACTOR = 0.030 MAXIMUM DEPTH(FEET) = 2.00 100 YEAR RAINFALL INTENSITY(INCH/HOUR) 7.377 NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINDTE. *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .8700 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) TRAVEL TIME THRU SUBAREA BASED ON VELOCITY (FEET/SEC.) AVERAGE FLOW DEPTH(FEET) 0.13 TRAVEL TIME (MIN.) Tc(MIN.) = 4.13 2.66 1.47 1.38 312.00 0.0295 0.39 SUBAREA AREA (ACRES) AREA-AVERAGE RUNOFF COEFFICIENT SUBAREA RUNOFF (CFS) 0.870 2.50 TOTAL AREA(ACRES) = 0.61 PEAK FLOW RATE(CFS) = 3.92 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH (FEET) = 0.16 FLOW VELOCITY(FEET/SEC.) 1.58 LONGEST FLOWPATH FROM NODE 101.00 TO NODE 103.00 = 192.20 FEET. **************************************************************************** FLOW PROCESS FROM NODE 104.00 TO NODE 103.00 IS CODE = 81 »»>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< 100 YEAR RAINFALL INTENSITY(INCH/HOUR) 7.377 NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINDTE. *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .8700 S.C.S. CURVE NUMBER (AMC II) = 0 AREA-AVERAGE RUNOFF COEFFICIENT = 0.8700 SUBAREA AREA(ACRES) 0.20 SUBAREA RUNOFF(CFS) TOTAL AREA (ACRES) 0.81 TOTAL RUNOFF(CFS) = TC(MIN.) = 4.13 1.28 5.20 *************************************************************************~** , FLOW PROCESS FROM NODE 103.00 TO NODE 105.00 IS CODE = 41 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING USER-SPECIFIED PIPESIZE (EXISTING ELEMENT) ««< ELEVATION DATA: UPSTREAM (FEET) = 302.40 DOWNSTREAM (FEET) 302.10 FLOW LENGTH{FEET) = 28.90 MANNING'S N = 0.013 DEPTH OF FLOW IN 18.0 INCH PIPE IS 9.1 INCHES PIPE-FLOW VELOCITY{FEET/SEC.) =' 5.78 GIVEN PIPE DIAMETER(INCH) = 18.00 NUMBER OF PIPES 1 PIPE-FLOW (CFS) = 5.20 PIPE TRAVEL TIME (MIN.) = 0.08 Tc{MIN.) = 4.22 LONGEST FLOWPATH FROM NODE 101.00 TO NODE 105.00 221.10 FEET. **************************************************************************** FLOW PROCESS FROM NODE 105.00 TO NODE 105.00 IS CODE = »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 1 ARE: TIME OF CONCENTRATION{MIN.) 4.22 RAINFALL INTENSITY(INCH/HR) = 7.38 TOTAL STREAM AREA (ACRES) = 0.81 PEAK FLOW RATE(CFS) AT CONFLUENCE = 5.20 1 **************************************************************************** FLOW PROCESS FROM NODE 106.00 TO NODE 107.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .9000 S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET) = UPSTREAM ELEVATION(FEET) = 322.00 DOWNSTREAM ELEVATION(FEET) = 321.00 ELEVATION DIFFERENCE (FEET) = 1.00 SUBAREA OVERLAND TIME OF FLOW (MIN.) '= 100 YEAR RAINFALL INTENSITY (INCH/HOUR) 60.00 2.352 7.377 NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINDTE. 2 I I I· I I I I I I I I I I I I I I SUBAREA RUNOFF (CFS) TOTAL AREA(ACRES) = 0.13 0.02 TOTAL RUNOFF(CFS) = 0.13 **********~***************************************************************** FLOW PROCESS FROM NODE 107.00 TO NODE 105.00 IS CODE = 62 »»>COMPUTE STREET FLOW TRAVEL TIME THRU SUBAREA««< »»>(STREET TABLE SECTION # 1 USED)««< 'UPSTREAM ELEVATION (FEET) = 321.00 DOWNSTREAM ELEVATION (FEET) STREET LENGTH(FEET) = 446.40 CURB HEIGHT(INCHES) = 6.0 STREET HALFWIDTH(FEET) = 15.00 DISTANCE FROM CROWN TO CROSSFALL GRADEBREAK(FEET) 10.00 INSIDE STREET CROSSFALL(DECIMAL) 0.020 OUTSIDE STREET CROSSFALL(DECIMAL) 0.020 SPECIFIED NUMBER OF HALFSTREETS CARRYING RUNOFF i Manning's FRICTION FACTOR for Streetflow Section(curb-to-curb) **TRAVEL TIME COMPUTED USING ESTIMATED FLOW (CFSr 0 • 62 STREETFLOW MODEL RESULTS USING ESTIMATED FLOW: STREET FLOW DEPTH(FEET) = 0.19 HALF STREET FLOOD WIDTH(FEET) = 3.42 AVERAGE FLOW VELOCITY(FEET/SEC.) 2.63 PRODUCT OF DEPTH&VELOCITY(FT*FT/SEC.) 0.51 STREET FLOW TRAVEL TIME(MIN.) = 2.82 Tc(MIN.) 5.18 100 YEAR RAINFALL INTENSITY(INCH/HOUR) 7.214 *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .9000 S.C.S. CURVE NUMBER (AMC II) = 0 AREA-AVERAGE RUNOFF COEFFICIENT 0.900 SUBAREA AREA(ACRES) 0.15 SUBAREA RUNOFF (CFS) 0.97 TOTAL AREA(ACRES) = 0.17 PEAK FLOW RATE(CFS) END OF SUBAREA STREET FLOW HYDRAULICS: DEPTH (FEET) = 0.23 HALF STREET FLOOD WIDTH(FEET) 5.22 FLOW VELOCITY(FEET/SEC.) = 2.83 DEPTH*VELOCITY(FT*FT/SEC.) LONGEST FLOWPATH FROM NODE 106.00 TO NODE 105.00 = 506.40 308.60 0.0150 1.10 0.65 FEET. **************************************************************************** FLOW PROCESS FROM NODE 108.00 TO NODE 105.00 IS CODE = 81 »»>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 7.214 *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .9000 S.C.S. CURVE NUMBER (AMC II) = 0 AREA-AVERAGE RUNOFF COEFFICIENT = 0.9000 SUBAREA AREA (ACRES) 0 . 12 SUBAREA RUNOFF (CFS) TOTAL AREA(ACRES) 0.29 TOTAL RUNOFF(CFS) = TC(MIN.) = 5.18 0.78 1.88 **************************************************************************** . FLOW PROCESS FROM NODE 105.00 TO NODE 105.00 IS CODE = »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< »»>AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES««< TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 2 ARE: TIME OF CONCENTRATION(MIN.) 5.18 RAINFALL INTENSITY(INCH/HR) = 7.21 TOTAL STREAM AREA(ACRES) = 0.29 PEAK FLOW RATE(CFS) AT CONFLUENCE 1.88 ** CONFLUENCE DATA ** STREAM RUNOFF Tc INTENSITY NUMBER (CFS) (MIN.) ( INCH/HOUR) 1 5.20 4.22 7.377 2 1. 88 5.18 7.214 AREA (ACRE) 0.81 0.29 RAINFALL INTENSITY AND TIME OF CONCENTRATION RATIO CONFLUENCE FORMULA USED FOR 2 STREAMS. ** PEAK FLOW RATE TABLE ** STREAM RUNOFF NUMBER (CFS) 1 6.73 2 6.97 Tc (MIN.) 4.22 5.18 INTENSITY (INCH/HOUR) 7.3~7 7.214 1 3 I I I I I I I I I I I I I I I I I I I COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: . PEAK FLOW RATE(CFS) 6.97 Tc(MIN.) = 5.18 TOTAL AREA(ACRES) = 1.10 LONGEST FLOWPATH FROM NODE 106.00 TO NODE 105.00 506.40 FEET. **************************************************************************** FLOW PROCESS FROM NODE 105.00 TO NODE 109.00 IS CODE = 41 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING USER-SPECIFIED PIPESIZE (EXISTING ELEMENT) ««< ELEVATION DATA: UPSTREAM (FEET) = 301.80 DOWNSTREAM (FEET) 301.70 FLOW LENGTH(FEET) = 13.30 MANNING'S N = 0.013 DEPTH OF FLOW IN 18.0 INCH PIPE IS 12.3 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 5.44 GIVEN PIPE DIAMETER(INCH) = 18.00 NUMBER OF PIPES 1 PIPE-FLOW (CFS) = 6.97 PIPE TRAVEL TIME (MIN.) = 0.04 Tc(MIN.) = 5.22 LONGEST FLOWPATH FROM NODE 106.00 TO NODE 109.00 519.70 FEET. **************************************************************************** FLOW PROCESS FROM NODE 109.00 TO NODE 109.00 IS CODE = 1 »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< TOTAL NUMBER OF STREAMS = 3 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 1 ARE: TIME OF CONCENTRATION(MIN.) 5.22 "RAINFALL INTENSITY(INCH/HR) = 7.18 TOTAL STREAM AREA(ACRES) = 1.10 PEAK FLOW RATE(CFS) AT CONFLUENCE = 6.97 **************************************************************************** FLOW PROCESS FROM NODE 110.00 TO NODE 111.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .7100 S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET) = 82.00 UPSTREAM ELEVATION(FEET) = 324.60 DOWNSTREAM ELEVATION(FEET) = 322.50 ELEVATION DIFFERENCE(FEET) = 2.10 SUBAREA OVERLAND TIME OF FLOW (MIN.) = 4.646 100 YEAR RAINFALL INTENSITY(INCH/HOUR) 7.377 NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINUTE. SUBAREA RUNOFF(CFS) 0.63 TOTAL AREA(ACRES) = 0.12 TOTAL RUNOFF(CFS) = 0.63 **************************************************************************** FLOW PROCESS FROM NODE 111.00 TO NODE 112.00 IS CODE = 51 »»>COMPUTE TRAPEZOIDAL CHANNEL FLOW««< »»>TRAVELTIME'THRU SUBAREA (EXISTING ELEMENT) ««< ELEVATION DATA: UPSTREAM (FEET) = 322.50 DOWNSTREAM (FEET) 313.00 caANNEL LENGTH THRU SUBAREA(FEET) = 344.50 CHANNEL SLOPE 0.0276 CHANNEL BASE(FEET) 0.00 "Z" FACTOR = 99.990 MANNING'S FACTOR = 0.030 MAXIMUM DEPTH(FEET) = 0.50 100 YEAR RAINFALL INTENSITY (INCH/HOUR) = 4.990 *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .8000 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) 1.80 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) 1.27 AVERAGE FLOW DEPTH(FEET) 0.12 TRAVEL TIME(MIN.) 4.52 TC(MIN.) = 9.17 SUBAREA AREA(ACRES) 0.58 SUBAREA RUNOFF(CFS) 2.32 AREA-AVERAGE RUNOFF COEFFICIENT 0.785 TOTAL AREA (ACRES) = 0.70 PEAK FLOW RATE (CFS) 2.74 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH (FEET) = 0.14 FLOW VELOCITY(FEET/SEC.) 1.39 LONGEST FLOWPATH FROM NODE 110.00 TO NODE 112.00 = 426.50 FEET. **************************************************************************** FLOW PROCESS FROM NODE 112.00 TO NODE 113.00 IS CODE = 62 »»>COMPUTE STREET FLOW TRAVEL TIME THRU SUBAREA««< 4 I I I I I I I I I I I I I I I I I I I »»>(STREET TABLE SECTION # 1 USED)««< ============================================================================ UPSTREAM ELEVATION(FEET) ~ 313.00 DOWNSTREAM ELEVATION(FEET) STREET LENGTH(FEET) ~ 187.80 CURB HEIGHT(INCHES) ~ 6.0 STREET HALFWIDTH(FEET) ~ 15.00 DISTANCE FROM CROWN TO CROSSFALL GRADEBREAK(FEET) 10.00 INSIDE STREET CROSSFALL(DECIMAL) 0.020 OUTSIDE STREET CROSSFALL(DECIMAL) 0.020 SPECIFIED NUMBER OF HALFSTREETS CARRYING RUNOFF 1 Manning's FRICTION FACTOR for Streetf10w Section(curb-to-curb) **TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) 2.97 STREETFLOW MODEL RESULTS USING ESTIMATED FLOW: STREET FLOW DEPTH(FEET) ~ 0.31 HALFSTREET FLOOD WIDTH(FEET) ~ 8.96 AVERAGE FLOW VELOCITY(FEETjSEC.) 3.23 PRODUCT OF DEPTH&VELOCITY(FT*FT/SEC.) 0.99 STREET FLOW TRAVEL TIME (MIN.) ~ 0.97 Tc(MIN.) 10.14 100 YEAR RAINFALL INTENSITY (INCH/HOUR) 4.676 *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT ~ .9000 S.C.S. CURVE NUMBER (AMC II) ~ 0 AREA-AVERAGE RUNOFF COEFFICIENT 0.800 SUBAREA AREA (ACRES) 0.11 SUBAREA RUNOFF(CFS) 0.46 308.60 0.0150 TOTAL AREA(ACRES) ~ 0.81 PEAK FLOW RATE(CFS) 3.03 END OF SUBAREA STREET FLOW HYDRAULICS: DEPTH (FEET) ~ 0.31 HALF STREET FLOOD WIDTH(FEET) 9.01 FLOW VELOCITY(FEET/SEC.) ~ 3.26 DEPTH*VELOCITY(FT*FT/SEC.) 1.00 LONGEST FLOWPATH FROM NODE 110.00 TO NODE 113·.00 ~ 614.30 FEET. **************************************************************************** FLOW PROCESS FROM NODE 114.00 TO NODE 113.00 IS CODE ~ 81 »»>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< ============================================================================ 100 YEAR RAINFALL INTENSITY(INCH/HOUR) ~ 4.676 *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT ~ .9000 S.C.S. CURVE NUMBER (AMC II) ~ 0 AREA-AVERAGE RUNOFF SUBAREA AREA(ACRES) TOTAL AREA (ACRES) TC(MIN.) ~ 10.14 COEFFICIENT ~ 0.8200 0.20 SUBAREA RUNbFF(CFS) 1.01 TOTAL RUNOFF(CFS) ~ 0.84 3.87 **************************************************************************** FLOW PROCESS FROM NODE ll3.00 TO NODE 109.00 IS CODE ~ 41 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING USER-SPECIFIED PIPESIZE (EXISTING ELEMENT)««< ============================================================================ ELEVATION DATA: UPSTREAM (FEET) ~ 301.80 DOWNSTREAM (FEET) ~ . 301.70 FLOW LENGTH(FEET) ~ 13.30 MANNING'S N ~ 0.013 DEPTH OF FLOW IN 18.0 INCH PIPE IS 8.4 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) ~ 4.76 GIVEN PIPE DIAMETER(INCH) ~ 18.00 NUMBER OF PIPES PIPE-FLOW (CFS) ~ 3.87 PIPE TRAVEL TIME (MIN.) ~ LONGEST FLOWPATH FROM NODE 0.05 Tc(MIN.) ~ llO.OO TO NODE 10.18 109.00 1 627.60 FEET. **************************************************************************** FLOW PROCESS FROM NODE 109.00 TO NODE 109.00 IS CODE ~ 1 »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< ========,==================================================================== TOTAL NUMBER OF STREAMS ~ 3 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 2 ARE: TIME OF CONCENTRATION(MIN.) 10.18 RAINFALL INTENSITY(INCH/HR) ~ 4.66 TOTAL STREAM AREA(ACRES) ~ 1.01 PEAK FLOW RATE(CFS) AT CONFLUENCE ~ 3.87 **************************************************************************** FLOW PROCESS FROM NODE ll5.00 TO NODE 116.00 IS CODE ~ 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< ============================================================================ *USER SPECIFIED (SUBAREA) : USE~-SPECIFIED RUNOFF COEFFICIENT ~ .9000 5 I I I I I I I I I I I I I I I I I S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET) = 65.00 UPSTREAM ELEVATION(FEET) = 318.50 DOWNSTREAM ELEVATION(FEET) = 317.50 ELEVATION DIFFERENCE(FEET) = 1.00 SUBAREA OVERLAND TIME OF FLOW(MIN.) = 2.514 100 YEAR RAINFALL INTENSITY(INCH/HOUR) 7.377 NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINDTE. SUBAREA RUNOFF(CFS) 0.33 TOTAL AREA (ACRES) = 0.05 TOTAL RUNOFF(CFS) = 0.33 **************************************************************************** FLOW PROCESS FROM NODE 116.00 TO NODE 117.00 IS CODE = 62 »»>COMPUTE STREET FLOW TRAVEL TIME THRU SUBAREA««< »»>(STREET TABLE SECTION # 2 USED)««< ============================================================================ UPSTREAM ELEVATION(FEET) STREET LENGTH(FEET) = STREET HALFWIDTH(FEET) 317.50 DOWNSTREAM ELEVATION(FEET) 85.30 CURB HEIGHT(INCHES) = 6.0 20.00 DISTANCE FROM CROWN TO CROSSFALL GRADEBREAK(FEET) 15.00 INSIDE STREET CROSSFALL(DEClMAL) 0.020 OUTSIDE STREET CROSSFALL(DEClMAL) 0.020 SPECIFIED NUMBER OF HALFSTREETS CARRYING RUNOFF 2 Manning's FRICTION FACTOR for Streetflow Section(curb-to-curb) **TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) STREETFLOW.MODEL RESULTS USING ESTIMATED FLOW: STREET FLOW DEPTH(FEET) = 0.21 HALFSTREET FLOOD WIDTH(FEET) = 3.99 AVERAGE FLOW VELOCITY(FEET/SEC.) 1.97 PRODUCT OF DEPTH&VELOCITY(FT*FT/SEC.) 0.41 STREET FLOW TRAVEL TIME(MIN.) = 0.72 Tc(MIN.) 3.23 100 YEAR RAINFALL INTENSITY (INCH/HOUR) 7.377 NOTE: RAINFALL INTENSITY IS BASED ON Tc 5-MINDTE. *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .9000 S.C.S. CURVE NUMBER (AMC II) = 0 AREA-AVERAGE RUNOFF COEFFICIENT SUBAREA AREA(ACRES) 0.23 TOTAL AREA(ACRES) = 0.28 0.900 SUBAREA RUNOFF (CFS l PEAK FLOW RATE(CFS) END OF SUBAREA STREET FLOW HYDRAULICS: DEPTH (FEET) = 0.24 HALF STREET FLOOD WIDTH(FEET) 5.58 1.10 1.53 316.20 0.0150 1.86 FLOW VELOCITY(FEET/SEC.) = 2.16 DEPTH*VELOCITY(FT*FT/SEC.) 0.51 LONGEST FLOWPATH FROM NODE 115.00 TO NODE 117.00 = 150.30 FEET. * * * ** * * * * ** * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ** *.**** *** ***** * * * * * * * ** * * FLOW PROCESS FROM NODE 11 7 . 00 TO NODE 109.00 IS CODE = 41 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING USER-SPECIFIED PIPESIZE (EXISTING ELEMENT) ««< ============================================================================ ELEVATION DATA: UPSTREAM (FEET) = 310.20 DOWNSTREAM (FEET) 301.70 FLOW LENGTH(FEET) = 393.90 MANNING'S N = 0.013 DEPTH OF FLOW IN 18.0 INCH PIPE IS 4.3 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 5.67 GIVEN PIPE DIAMETER(INCH) = 18.00 NUMBER OF PIPES 1 PIPE-FLOW (CFS) = 1.86 PIPE TRAVEL TIME(MIN.) = 1.16 Tc(MIN.) = 4.39 LONGEST FLOWPATH FROM NODE 115.00 TO NODE 109.00 544.20 FEET. **************************************************************************** FLOW PROCESS FROM NODE 109.00 TO NODE 109.00 IS CODE = »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< »»>AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES««< 1 ============================================================================ TOTAL NUMBER OF STREAMS = 3 CONFLUENCE VA4UES USED FOR INDEPENDENT STREAM 3 ARE: TIME OF CONCENTRATION(MIN.) 4.39 RAINFALL INTENSITY(INCH/HR) = 7.38 TOTAL STREAM AREA(ACRES) = 0.28 PEAK FLOW RATE(CFS) AT CONFLUENCE = 1.86 ** CONFLUENCE DATA ** STREAM RUNOFF NUMBER (CFS) 1 6.97 Tc (MIN.) 5.22 INTENSITY (INCH/HOUR) 7.177 AREA (ACRE) 1.10 i 6 I I I I I I I I I I I I I I I I I I I 2 3.S7 10.lS 4.662 1.01 3 1.S6 4.39 7.377 0.2S RAINFALL INTENSITY AND TIME OF CONCENTRATION RATIO CONFLUENCE FORMULA USED FOR 3 STREAMS. ** PEAK FLOW RATE TABLE ** STREAM RUNOFF Tc INTENSITY NUMBER (CFS) (MIN.) (INCH/HOUR) 1 10.31 4.39 7.377 2 10.76 5.22 7.177 3 9.57 10.1S 4.662 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE(CFS) 10.76 Tc(MIN.) = 5.22 TOTAL AREA(ACRES) = 2.39 LONGEST FLOWPATH FROM NODE 110.00 TO NODE 109.00 627.60 FEET. **************************************************************************** FLOW PROCESS FROM NODE 106.00 TO NODE 120.00 IS CODE = 41 »»>~OMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING USER-SPECIFIED PIPESIZE (EXISTING ELEMENT) ««< ELEVATION DATA: UPSTREAM (FEET) = 301.30 DOWNSTREAM (FEET) 275.S0 FLOW LENGTH(FEET) = 101.60 MANNING'S N = 0.013 DEPTH OF FLOW IN 18.0 INCH PIPE IS 5.7 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 22.52 GIVEN PIPE DIAMETER(INCH) = lS.00 NUMBER OF PIPES 1 PIPE-FLOW (CFS) = 10.76 PIPE TRAVEL TIME(MIN.) = 0.08 Tc(MIN.) = 5.29 LONGEST FLOWPATH FROM NODE 110.00 TO NODE 120.00 729.20 FEET. +--------------------------------------------------------------------------+ I END ANALYSIS OF NEIGHBORHOOD 1.2 -FUTURE COMMERCIAL SITE I I (NODE SERIES 100) I- I I +--------------------------------------------------------------------------+ +--------------------------------------------------------------------------+ I BEGIN ANALYSIS OF NEIGHBORHOOD 1.3 -PROPOSED RV STORAGE SITE AND I I FUTURE MULTI-FAMILY RESIDENTIAL DEVELOPMENT I I (NODE SERIES 200) I +--------------------------------------------------------------------------+ **************************************************************************** FLOW PROCESS FROM NODE 201.00 TO NODE 202.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .9000 S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET) = 60.00 UPSTREAM ELEVATION(FEET) = 321.20 DOWNSTREAM ELEVATION(FEET) = 320.60 ELEVATION DIFFERENCE (FEET) = 0.60 SUBAREA OVERLAND TIME OF FLOW(MIN.) = 2.789 100 YEAR RAINFALL INTENSITY(INCH/HOUR) 7.377 NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINUTE. SUBAREA RUNOFF(CFS) 0.46 TOTAL AREA(ACRES) = 0.07 TOTAL RUNOFF(CFS) = 0.46 **************************************************************************** FLOW PROCESS FROM NODE 202.00 TO NODE 205.00 IS CODE = 51 »»>COMPUTE TRAPEZOIDAL CHANNEL FLOW««< - »»>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT) ««< ELEVATION DATA: UPSTREAM (FEET) = 320.60 DOWNSTREAM (FEET) 313.80 CHANNEL LENGTH THRU SUBAREA(FEET) = 460.40 CHANNEL SLOPE 0.0148 -CHANNEL BASE(FEET) 0.00-"Z" FACTOR = 2.000 MANNING'S FACTOR = 0.015 MAXIMUM DEPTH(FEET) = 1.00 100 YEAR RAINFALL INTENSITY (INCH/HOUR) 7.377 NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINUTE.- *U~ER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .9000 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) 1.73 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) 4.17 AVERAGE FLOW DEPTH (FEET) = 0.45 TRAVEL TIME(MIN.) 1.S4 7 I I I I I I I , I I I I I,. I I I Tc(MIN.) = 4.63 SUBAREA AREA(ACRES) 0.38 SUBAREA RUNOFF (CFS) = 0.900 2.52 AREA-AVERAGE RUNOFF COEFFICIENT TOTAL AREA(ACRES) = 0.45 PEAK FLOW RATE(CFS) = 2.99 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH (FEET) = 0.56 FLOW VELOCITY(FEET/SEC.) LONGEST FLOWPATH FROM NODE 201.00 TO NODE 4.77 205.00 = 520.40 FEET. **************************************************************************** FLOW PROCESS FROM NODE 205.00 TO NODE 205.00 IS CODE = 1 »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< ============================================================================ TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 1 ARE: TIME OF CONCENTRATION(MIN.) 4.63 RAINFALL INTENSITY (INCH/HR) = 7.38 TOTAL STREAM AREA(ACRES) = 0.45 PEAK FLOW RATE(CFS) AT CONFLUENCE = 2.99 **************************************************************************** FLOW PROCESS FROM NODE 206.00 TO NODE 207.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .9000 S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET) = 60.00 UPSTREAM ELEVATION(FEET) = 321.00 DOWNSTREAM ELEVATION(FEET) = 320.40 ELEVATION DIFFERENCE (FEET) = 0.60 SUBAREA OVERLAND TIME OF FLOW(MIN.) = 2.789 100 YEAR RAINFALL INTENSITY(INCH/HOUR) 7.377 NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINUTE. SUBAREA RUNOFF(CFS) 0.40 TOTAL AREA(ACRES) = 0.06 TOTAL RUNOFF(CFS) = 0.40 **************************************************************************** FLOW PROCESS FROM NODE 207.00 TO NODE 208.00 IS CODE = 51 »»>COMPUTE TRAPEZOIDAL CHANNEL FLOW««< »»>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT) ««< ============================================================================ ELEVATION DATA: UPSTREAM (FEET) = 320.40 DOWNSTREAM (FEET) CHANNEL LENGTH THRU SUBAREA(FEET) = 155.10 CHANNEL SLOPE CHANNEL BASE(FEET) 0.00 "Z" FACTOR = 11.540 MANNING'S FACTOR = 0.015 MAXIMUM DEPTH(FEET) = '100 YEAR RAINFALL INTENSITY(INCH/HOUR) 7.377 0.25 NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINUTE. *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .9000 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) AVERAGE FLOW DEPTH(FEET) 0.19 TRAVEL TIME(MIN.) TC(MIN.) = 3.65 1.29 2.99 0.86 317.00 0.0219 0.27 SUBAREA AREA(ACRES) AREA-AVERAGE RUNOFF COEFFICIENT SUBAREA RUNOFF (CFS) 0.900 '1. 79 TOTAL AREA(ACRES) = 0.33 PEAK FLOW RATE (CFS) =. 2.19 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH'(FEET) = 0.23 FLOW VELOCITY(FEET/SEC.) 3.48 LONGEST FLOWPATH FROM NODE 206.00 TO NODE 208.00 = 215.10 FEET. **************************************************************************** FLOW PROCESS FROM NODE 209.00 TO NODE 208.00 IS CODE = 81 »»>ADDITION OF SUBAREA. TO MAINLINE PEAK FLOW««< ============================================================================ 100 YEAR RAINFALL INTENSITY (INCH/HOUR) NOTE: RAINFALL INTENSITY IS BASED ON Tc = *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .9000 S.C.S .. CURVE NUMBER (AMC II) = 0 COEFFICIENT = 0.9000 7.377 5-MINUTE. AREA-AVERAGE RUNOFF SUBAREA AREA(ACRES) TOTAL AREA'(ACRES) TC(MIN.) = 3.65 0.21 SUBAREA RUNOFF(CFS) 0.54 TOTAL RUNOFF(CFS) = 1.39 3.59 8 I I, I I I I I I I I I I I I I I' I **************************************************************************** FLOW PROCESS FROM NODE 208.00 TO NODE 205.00 IS CODE = 51 »»>COMPUTE TRAPEZOIDAL CHANNEL FLOW««< »»>TRAVELTlME THRU SUBAREA (EXISTING ELEMENT) ««< ============================================================================ ELEVATION DATA: UPSTREAM (FEET) = 317.00 DOWNSTREAM (FEET) 313.80 CHANNEL LENGTH THRU SUBAREA{FEET) = 88.90 CHANNEL SLOPE 0.0360 CHANNEL BASE{FEET) 0.00 "Z" FACTOR = 99.990 MANNING'S FACTOR = 0.015 MAXIMUM DEPTH{FEET) = 0.25 100 YEAR RAINFALL INTENSITY (INCH/HOUR) 7.377 NOTE: RAINFALL INTENSITY IS BASED ON Tc = 5-MINUTE. *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .9000 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW{CFS) 3.62 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY{FEET/SEC.) 2.91 AVERAGE FLOW DEPTH{FEET) 0.11 TRAVEL TIME{MIN.} 0.51 TC{MIN.} = 4.16 SUBAREA AREA{ACRES} 0.01 SUBAREA RUNOFF{CFS} 0.07 AREA-AVERAGE RUNOFF COEFFICIENT 0.900 TOTAL AREA{ACRES) = 0.55 PEAK FLOW RATE{CFS} 3.65 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH {FEET} = 0.11 FLOW VELOCITY{FEET/SEC.) LONGEST FLOWPATH FROM NODE 206.00 TO NODE 2.93 205.00 = 304.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 205.00 TO NODE 205.00 IS CODE = »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< »»>AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES««< TOTAL NUMBER OF STREAMS = 2 CONFLUENCE' VALUES USED FOR INDEPENDENT STREAM 2 ARE: TIME OF CONCENTRATION{MIN.) 4.16 RAINFALL INTENSITY{INCH/HR} = 7.38 TOTAL STREAM AREA{ACRES} = 0.55 PEAK FLOW RATE{CFS} AT CONFLUENCE = 3.65 ** CONFLUENCE DATA ** STREAM RUNOFF Tc INTENSITY NUMBER {CFS} {MIN.} {INCH/HOUR} 1 2.99 4.63 7.377 2 3.65 4.16 7.377 AREA {ACRE} 0.45 0.55 RAINFALL INTENSITY AND TIME OF CONCENTRATION RATIO CONFLUENCE FORMULA USED FOR 2 STREAMS. ** PEAK FLOW RATE TABLE ** STREAM RUNOFF Tc INTENSITY NUMBER {CFS} {MIN.} { INCH/HOUR} 1 6.34 4.16 7.377 2 6.64 4.63 7.377 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE {CFS} 6.64 Tc {MIN.} = 4.63 TOTAL AREA{ACRES} = 1.00 1 LONGEST FLOWPATH FROM NODE 201.00 TO NODE 205.00 520.40 FEET. +-----------------------------------------------------------------------~--+ I At Node 205, the first-flush runoff, Q85=0.'18-cfs, will drain into the I I grassy swale, while the rest of the runoff, Ql00=6.46-cfs, will kkeep I I flowing along the AC berm towards the curb inlet downstream. I +---------------------------~----------------------------------------------+ **************************************************************************** FLOW PROCESS FROM NODE 205.00 TO NODE 205.00 IS CODE =' 7 »»>USER SPECIFIED HYDROLOGY INFORMATION AT NODE««< ============================================================================ USER-SPECIFIED VALUES ARE AS FOLLOWS: TC{MIN} = 5.00 RAIN INTENSITY{INCH/HOUR) = 7.38 TOTAL AREA{ACRES} = 0.99 TOTAL RUNOFF{CFS} = 6.46 +--------------------------------------------------------------------------+ I The Code 7 above pertains to the peak discharge, Q100=6.46-cfs, that I I keeps flowing along the AC berm towards the curb inlet downstream. I I I +--------------------------------------------------------------------------+ 9 I I I I I ,I I I I I I I I I I I I I I **************************************************************************** FLOW PROCESS FROM NODE 205.00 TO NODE 2l0,00 IS CODE = 5l ----------------------------------------------------------------------~----- »»>COMPUTE TRAPEZOIDAL CHANNEL FLOW««< »»>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT)««< ============================================================================ ELEVATION DATA: UPSTREAM (FEET) = 3l3.80 DOWNSTREAM (FEET) 300.90 CHANNEL LENGTH THRU SUBAREA(FEET) = 457.20 CHANNEL SLOPE 0.0282 CHANNEL BASE(FEET) 0.00 "Z" FACTOR = 2.000 MANNING'S FACTOR = 0.Ol5 MAXIMUM DEPTH(FEET) = l.OO lOO YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.569 *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNoFF COEFFICIENT = .9000 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) 7.55 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) 7.73 AVERAGE FLOW DEPTH(FEET) 0.70 TRAVEL TlME(MIN.) 0.99 Tc(MIN.) = 5.99 SUBAREA AREA(ACRES) 0.37 SUBAREA RUNOFF (CFS) 2.l9 AREA-AVERAGE RUNOFF COEFFICIENT 0.889 TOTAL AREA(ACRES) = 1.36 PEAK FLOW RATE (CFS) = 7.94 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH (FEET) = 0.7l FLOW VELOCITY(FEET/SEC.) 7.78 LONGEST FLOWPATH FROM NODE 20l.00 TO NODE 2l0.00 = 977 . 60 FEET. **************************************************************************** FLOW PROCESS FROM NODE 2l0.00 TO NODE 2l0.00 IS CODE = 1 >>>>>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE<'«« ============================================================================ TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 1 ARE: TIME OF CONCENTRATION(MIN.) 5.99 RAINFALL INTENSITY(INCH/HR) = 6.57 TOTAL STREAM AREA(ACRES) = 1.36 PEAK FLOW RATE(CFS) AT CONFLUENCE = 7.94 **************************************************************************** FLOW PROCESS FROM NODE 2l1.00 TO NODE 2l2.00 IS CODE = 2l »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .7l00 S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET) = 65.00 UPSTREAM ELEVATION(FEET) = 3l3.00 DOWNSTREAM ELEVATION(FEET) = 312.30 ELEVATION DIFFERENCE(FEET) = 0.70 SUBAREA OVERLAND TIME OF FLOW (MIN.) = 5.522 lOO YEAR RAINFALL INTENSITY (INCH/HOUR) 6.920 SUBAREA RUNOFF (CFS) 0.29 TOTAL AREA(ACRES) = 0.06 TOTAL RUNOFF(CFS) 0.29 **************************************************************************** FLOW PROCESS FROM NODE 2l2.00 TO NODE 2l3.00 IS CODE = 5l »»>COMPUTE TRAPEZOIDAL CHANNEL FLOW««< »»>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT) ««< ============================================================================ ELEVATION DATA: UPSTREAM (FEET) = 3l2.30 DOWNSTREAM (FEET) 3l0.00 CHANNEL LENGTH THRU SUBAREA(FEET) = 98.30 CHANNEL SLOPE 0.0234 CHANNEL BASE(FEET) 0,00 "Z" FACTOR = 99.990 MANNING'S FACTOR = 0.030 MAXIMUM DEPTH(FEET) = 0.50 lOO YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.906 *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .7l00 S'.C.S. CURVE NUMBER (AMC II) = '0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) l.ll TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) l.07 AVERAGE FLOW DEPTH(FEET) O.lO TRAVEL TIME(MIN.) l.54 Tc(MIN.) = 7.06 SUBAREA AREA(ACRES) 0.39 SUBAREA RUNOFF (CFS) 1.64 AREA-AVERAGE RUNOFF COEFFICIENT 0.7l0 TOTAL AREA(ACRES) = 0.45 PEAK FLOW RATE(CFS) l.89 END OF SUBAREA CHANNEL FLOW HYDRAULICS: ,DEPTH(FEET) = 0.l2 FLOW VELOCITY(FEET/SEC.) l.2l LONGEST FLOWPATH FROM NODE 2ll.00 TO NODE 2l3.00 = l63.30 FEET. I I I I I I I I I I I I I I I I I I **************************************************************************** FLOW PROCESS FROM NODE 213.00 TO NODE 210.00 IS CODE = 41 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING USER-SPECIFIED PIPESIZE (EXISTING ELEMENT)««< ============================================================================ ELEVATION DATA: UPSTREAM (FEET) = 306.00 DOWNSTREAM (FEET) 291.10 FLOW LENGTH(FEET) = 80.40 MANNING'S N = 0.013 DEPTH OF FLOW IN 24.0 INCH PIPE IS 2.4 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 11.71 GIVEN PIPE DIAMETER(INCH) = 24.00 NUMBER OF PIPES 1 PIPE-FLOW (CFS) = 1.89 PIPE TRAVEL TIME(MIN.) = 0.11 Tc(MIN.) = 7.17 LONGEST FLOWPATH FROM NODE 211.00 TO NODE 210.00 243.70 FEET. '**************************************************************************** FLOW PROCESS FROM NODE 210.00 TO NODE 21. 00 IS CODE = 1 »>>>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< »»>AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES««< ============================================================================ TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 2 ARE: TIME OF CONCENTRATION(MIN.) 7.17 RAINFALL INTENSITY (INCH/HR) = 5.85 TOTAL STREAM AREA (ACRES) = 0.45 PEAK FLOW RATE(CFS) AT CONFLUENCE = 1.89 ** CONFLUENCE DATA ** STREAM RUNOFF Tc INTENSITY NUMBER (CFS)-(MIN.) ( INCH/HOUR) 1 7.94 5.99 6.569 2 1.89 7.17 5.845 AREA (ACRE) 1.36 0.45 RAINFALL INTENSITY AND TIME OF CONCENTRATION RATIO CONFLUENCE FORMULA USED FOR 2 STREAMS. ** PEAK FLOW RATE TABLE ** STREAM RUNOFF Tc INTENSITY NUMBER (CFS) (MIN.) ( INCH/HOUR) 1 9.51 5.99 6.569 2 8.95 7.17 5.845 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE(CFS) 9.51 Tc(MIN.) = 5.99 TOTAL AREA(ACRES) = 1.81 LONGEST FLOWPATH FROM NODE 201.00 TO'NODE 21.00 977.60 FEET. **************************************************************************** FLOW PROCESS FROM NODE 21. 00 TO NODE 213.00 IS CODE = 41 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING USER-SPECIFIED PIPESIZE (EXISTING ELEMENT)««< ============================================================================ ELEVATION DATA: UPSTREAM (FEET) = 290.70 DOWNSTREAM (FEET) FLOW LENGTH(FEET) = 55.30 MANNING'S N = 0.013 DEPTH OF FLOW IN 24.0 INCH PIPE IS 11.5 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 6.38 GIVEN PIPE DIAMETER (INCH) = 24.00 NUMBER OF PIPES PIPE-FLOW (CFS) = 9.51 0.14 Tc(MIN.) = 6.13 1 290.20 PIPE TRAVEL TIME(MIN.) = LONGEST FLOWPATH FROM NODE 201.00 TO NODE 213.00 1032.90 FEET. **************************************************************************** FLOW PROCESS FROM NODE 213.00 TO NODE 213.00 IS CODE = 10 »»>MAIN-STREAM MEMORY COPIED ONTO MEMORY BANK # 1 ««< ============================================================================ **************************************************************************** FLOW PROCESS FROM NODE 215.00 TO NODE 216.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< ============================================================================ *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .7100 'S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET) = 65.00 UPSTREAM ELEVATION(FEET) = 322.00 DOWNSTREAM ELEVATION(FEET) 321.40 ELEVATION DIFFERENCE (FEET) 0.60 11 I I I I I I I I I I I I I I I SUBAREA OVERLAND TIME OF FLOW(MIN.) = 5.709 WARNING: INITIAL SUBAREA'FLOW PATH LENGTH IS GREATER THAN THE MAXIMUM OVERLAND FLOW LENGTH = 62.69 (Reference: Table 3-1B of Hydrology Manual) THE MAXIMUM OVERLAND FLOW LENGTH IS USED IN Tc CALCULATION! 100 YEAR RAINFALL INTENSITY (,INCH/HOUR) = 6.773 SUBAREA RUNOFF (CFS) 0.34, TOTAL AREA(ACRES) = 0.07 TOTAL RUNOFF(CFS) 0.34 **************************************************************************** FLOW PROCESS FROM NODE 216.00 TO NODE 217.00 IS CODE = 51 »»>COMPUTE TRAPEZOIDAL CHANNEL FLOW««< »»>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT,) ««< ELEVATION DATA: UPSTREAM (FEET) = 321.40 DOWNSTREAM (FEET) 320.90 CHANNEL LENGTH THRU SUBAREA(FEET) = 194.80 CHANNEL SLOPE 0.0026 CHANNEL BASE(FEET) 0.00 "Z" FACTOR = 99.990 MANNING'S FACTOR = 0.030 MAXIMUM DEPTH(FEET) = 0.50 100 YEAR'RAINFALL INTENSITY (INCH/HOUR) = 4.018 *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .7100 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) 1.10 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) 0.46 AVERAGE FLOW DEPTH(FEET) 0.16 TRAVEL TIME(MIN.) 7.12 Tc(MIN.) = 12.83 SUBAREA AREA(ACRES) 0.52 SUBAREA RUNOFF (CFS) 1.48 AREA-AVERAGE RUNOFF COEFFICIENT 0.710 TOTAL AREA(ACRES) = 0.59 PEAK FLOW RATE(CFS) 1.68 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH (FEET) = 0.18 FLOW VELOCITY(FEET/SEC.) 0.52 LONGEST FLOWPATH FROM NODE 215.00 TO NODE 217.00 = 259.80 FEET. **************************************************************************** FLOW PROCESS FROM NODE 217.00 TO NODE 218.00 IS CODE = 51 »»>COMPUTE TRAPEZOIDAL CHANNEL FLOW««< »»>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT) ««< ELEVATION DATA: UPSTREAM (FEET) = 320.90 DOWNSTREAM (FEET) CHANNEL LENGTH THRU SUBAREA(FEET) = 465.50 CHANNEL SLOPE CHANNEL BASE(FEET) 0.00 "Z" FACTOR = 99.990 MANNING'S FACTOR = 0.030 MAXIMUM DEPTH(FEET) = 0.50 100 YEAR RAINFALL INTENSITY (INCH/HOUR) = 3.045 *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .7100 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) ,AVERAGE FLOW DEPTH(FEET) 0.15 TRAVEL TIME(MIN.) Tc(MIN.) = 19.71 2.46 1.13' 6.89 313.20 0.0165 0.72 SUBAREA AREA(ACRES) AREA-AVERAGE RUNOFF COEFFICIENT SUBAREA RUNOFF (CFS) 0.710 1.56 TOTAL AREA (ACRES) = 1.31 PEAK FLOW RATE(CFS) = 2.83 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH(FEET)' = 0.16 FLOW VELOCITY(FEET/SEC.) 1.17 LONGEST FLOWPATH FROM NODE 215.00 TO NODE 218.00 = 725.30 FEET. **************************************************************************** FLOW PROCESS FROM NODE 218.00 TO NODE 218.00 IS CODE = 1 »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< ============================================================================ TOTAL NUMBER OF STREAMS = 2 ' CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 1 ARE: TIME OF CONCENTRATION(MIN.) 19.72 RAINFALL INTENSITY(INCH!HR) = 3.04 TOTAL STREAM AREA(ACRES) = 1.31 PEAK FLOW RATE(CFS) AT CONFLUENCE = 2.83 ***********************************************************~**************** FLOW PROCESS FROM NODE 218.00 TO NODE 218.00 IS CODE = 7 »»>USER SPECIFIED HYDROLOGY INFORMATION AT NODE««< ============================================================================ USER-SPECIFIED VALUES ARE AS FOLLOWS: TC(MIN) = 5.00 RAIN INTENSITY (INCH/HOUR) , = 7.38 TOTAL AREA(ACRES) = 0.01 TOTAL RUNOFF(CFS) = 0.18 12 I I I I I I I I I I I I I I I I +----~-----------------------------------------------------~---------------+ I The Code 7 above pertains to the first-flush runoff, Q85=0.18-cfs, from I I Private Drive "A" and the proposed RV Storage Site that drains into the I I grassy swal~. I +------------------------------~-------------------------------------------+ **************************************************************************** FLOW PROCESS FROM NODE 218.00 TO NODE 218.00 IS CODE = »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< »»>AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES««< TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 2 ARE: TIME OF CONCENTRATION{MIN.) 5.00 RAINFALL INTENSITY (INCH/HR) = 7.38 TOTAL STREAM AREA{ACRES) = 0.01 PEAK FLOW RATE{CFS) AT CONFLUENCE = 0.18, ** CONFLUENCE DATA ** STREAM RUNOFF NUMBER (CFS) 1 2.83 2 0.18 Tc (MIN.) 19.72 ·5.00 INTENSITY (INCH/HOUR) 3.045 7.377 AREA (ACRE) 1.31 0.01 RAINFALL INTENSITY AND TIME OF CONCENTRATION RATIO CONFLUENCE FORMULA USED FOR 2 STREAMS. ** PEAK FLOW RATE TABLE ** STREAM RUNOFF Tc INTENSITY NUMBER (CFS) (MIN.) (INCH/HOUR) 1 0.90 5.00 7.377 2 2.91 19.72 3.045 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE{CFS) = 2.91 Tc{MIN.) = 19.72 TOTAL AREA{ACRES) = 1.32 1 LONGEST FLOWPATH FROM NODE 215.00 TO NODE 218.00 725.30 FEET. **************************************************************************** FLOW PROCESS FROM NODE 218.00 TO NODE 219.00 IS CODE = 51. »»>COMPUTE TRAPEZOIDAL CHANNEL FLOW««< »»>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT) ««< ELEVATION DATA: UPSTREAM (FEET) = 313.20 DOWNSTREAM (FEET) 311.80 CHANNEL LENGTH THRU SUBAREA{FEET) = 137.00 CHANNEL SLOPE 0.0102 CHANNEL BASE{FEET) 4.00 "Z" FACTOR = 3.000 MANNING'S FACTOR = 0.250 MAXIMUM DEPTH{FEET) = 1.25 100 YEAR RAINFALL INTENSITY(INCH!HOUR) = 2.646 *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .7100 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) 3.60 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY (FEET/SEC. ) 0.48 AVERAGE FLOW DEPTH{FEET) 1.06 TRAVEL TIME{MIN.) 4.80 . Tc{MIN.) = 24.51 SUBAREA AREA (ACRES) 0.74 SUBAREA RUNOFF{CFS) 1.39 AREA-AVERAGE RUNOFF COEFFICIENT 0.718 TOTAL AREA{ACRES) = 2.06 PEAK FLOW RATE(CFS) = 3.92 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH (FEET) = 1.10 FLOW VELOCITY{FEET/SEC.) 0.49 LONGEST FLOWPATH FROM NODE 215.00 TO NODE 219.00 = 862.30 FEET. **************************************************************************** FLOW PROCESS FROM NODE 219.00 TO NODE 203.00 IS CODE = 51 ----------------------------~----------------------:------------------------»»>COMPUTE TRAPEZOIDAL CHANNEL FLOW««< »»>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT) ««< ELEVATION DATA: UPSTREAM (FEET) = 311.80 DOWNSTREAM{FEET). = 307.10 CHANNEL LENGTH THRU SUBAREA{FEET) = 200.10 CHANNEL SLOPE 0.0235 CHANNEL BASE{FEET) 0.00 "Z" FACTOR = 99.990 MANNING'S FACTOR = 0.030 MAXIMUM DEPTH{FEET) = 0.50 100 YEAR RAINFALL INTENSITY(INCH/HOUR) '" 2.509 *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .7100 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW{CFS) 5.16 13 I I I I I I I I I I I I I I I I I I I TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) 1.59 AVERAGE FLOW DEPTH(FEET) 0.18 TRAVEL TlME(MIN.) 2.10 Tc(MIN.) = 26.61 SUBAREA AREA (ACRES) 1. 40 SUBAREA RUNOFF (CFS) 2 .49 AREA-AVERAGE RUNOFF COEFFICIENT 0.715 TOTAL AREA (ACRES) = 3.46 PEAK FLOW RATE(CFS) = 6.21 END' OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH (,FEET) = 0.20 FLOW VELOCITY(FEET/SEC.) 1.62 LONGEST FLOWPATH FROM'NODE 215.00 TO NODE 203.00 = 1062.40 FEET. **************************************************************************** FLOW PROCESS FROM NODE . 203.00 TO NODE 213.00 IS CODE = 41 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING,USER-SPECIFIED PIPESIZE (EXISTING ELEMENT) ««< ELEVATION DATA: UPSTREAM (FEET) = 299.00 DOWNSTREAM (FEET) FLOW LENGTH(FEET) = 68.00 MANNING'S N = 0.013 DEPTH OF FLOW IN 24.0 INCH PIPE IS 4.6 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 14.74 GIVEN PIPE DIAMETER(INCH) = 24.00 NUMBER OF PIPES PIPE-FLOW (CFS) = 6.21 0.08 Tc(MIN.) = 26.69 1 290.20 PIPE TRAVEL TIME (MIN.) = LONGEST FLOWPATH FROM NODE 215.00 TO NODE 213.00 1130.40 FEET. **************************************************************************** FLOW PROCESS FROM NODE 213.00 TO NODE 213.00 IS CODE = 11 »»>CONFLUENCE MEMORY BANK # 1 WITH THE MAIN-STREAM MEMORY««< ~=~========================================================================= ** MAIN STREAM CONFLUENCE DATA ** STREAM RUNOFF Tc INTENSITY AREA NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE) 1 6.21 26.69 2.505 3.46 LONGEST FLOWPATH FROM NODE 215.00 TO NODE 213.00 1130.40 FEET. ** MEMORY BANK # 1 CONFLUENCE DATA ** STREAM RUNOFF Tc INTENSITY AREA NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE) 1 9.51 6.13 6.468 1.81 LONGEST FLOWPATH FROM NODE 201. 00 TO NODE 213.00 1032.90 FEET. ** PEAK FLOW RATE TABLE ** STREAM RUNOFF Tc INTENSITY NUMBER (CFS) (MIN.) ( INCH/HOUR) 1 10.94 6.13 6.468 2 9.89 26.69 2.505 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE (CFS) 10.94 Tc (MIN.) = 6.13 TOTAL AREA(ACRES) = 5.27 * * * *-** * ** ** * * * ** ** ** * ** ** * ** * * * * * * * * ** * * * * ** * * * ** * ** * * * ** * * * * * ** * * ** ** * * * * * * FLOW PROCESS FROM NODE 213.00 TO NODE 213.00 IS CODE = 12 »»>CLEAR MEMORY BANK # 1 ««< ============================================================================ **************************************************************************** FLOW PROCESS FROM NODE 213.00 TO NODE 204.00 IS CODE = 41 »»>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA««< »»>USING USER-SPECIFIED PIPESIZE (EXISTING ELEMENT) ««< ============================================================================ ELEVATION DATA: UPSTREAM (FEET) = 289.70 DOWNSTREAM (FEET) 287.00 FLOW LENGTH(FEET) = 95.30 MANNING'S N = 0.013 DEPTH OF FLOW IN 24.0 INCH PIPE IS 9.1 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 10.08 GIVEN PIPE DIAMETER (INCH) = 24.00 NUMBER OF PIPES PIPE-FLOW (CFS) = 10.94 PIPE TRAVEL TIME(MIN.) = LONGEST FLOWPATH FROM NODE 0.16 Tc(MIN.) = 215.00 .TO NODE 6.29 204.00 1 1225.70 FEET. +--------------------------------------------------------------------------+ I END ANALYSIS FOR NEIGHBORHOOD 1.3 -PROPOSED RV STORAGE SITE AND' I I FUTURE MULTI-FAMILY RESIDENTIAL DEVELOPMENT I I (NODE SERIES 200) I +--------------------------------------------------------------------------+ ============================================================================ 14 I I I. I I I I I I I I I I 1 I I I I I END OF STUDY SUMMARY: TOTAL AREA(ACRES) PEAK FLOW RATE(CFS) 5.27 TC(MIN.) = 10.94 6.29 ==;========================================================================= ============================================================================ END OF RATIONAL METHOD ANALYSIS 15 I I I I I I I I I I I I I I I' I I, I, I~· __~ ____ ~~ ____ _ IV I I I I I I I I I I I I I I I I II I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 Chapter 4 HYDRAULIC ANALYSIS 4.1 -Neighborhood 1.2 StormCAD Model Output AH:ad H:IREPORTS\23S2I146\A02.doc W.O.23S2,146/170 8/21/2006 8:23 liM -------------------Scenario: LA COSTA GREENS -DEVELOPED CONDITIONS: NEIGHBORHOOD 1.2 (SOUTH) LO I a.. CDS ....... I a.. 1-113 HW-120 h:\stormcad\2352\146\neigh 1.2-south.stm 08/11/06 12:01.:50 PM RSR-103 P-2 CO P-1 .-/.7 '~~ STREET A Hunsaker & Associates San Diego, Inc © Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA +1-203-755-1666 1-117 Storm CAD v5.5 [5.50051 Page 1 of 1 -- - ---_.--- - -- ---Scenario: LA COSTA GREENS .-DEVELOPED CONDITIONS: NEIGHBORHOOD 1.2 (SOUTH) Label ~pstrearr Downstrearr Upstream pownstrearr Node Node Invert Invert Elevation Elevation (tt) .(tt) P-3 1-113 CO-109 301.78 301.65 P-5 1-105 CO-109 301.78 301.65 P-4 RSR-10 1-105 302.37 302.11 P-6 CO-109 CDS 301.32 300.81 P-7 CDS HW-120 300.81 275.76 P-1 1-117 CO 310.22 304.76 P-2 CO CO-109 304.43 301.65 h:\stormcad\2352\ 146\neigh 1.2-south.stm 08/11/06 12:02:01 PM Combined Pipe\Node Report ~pstream pownstrearr Length ~onstructec Hydraulic Section Material Mannings Hydraulic Hydraulic Average Total Flowl Ground Ground (tt) Slope Slope Size n Grade Grade Velocity (cfs) Elevation Elevation (%) . (%) Line In Line Out (tus) (tt) (tt) (ttl (tt) 309.10 309.40 13.25 .0.98 0.14 18 inch Concret 0.013 303.79 303.77 2.19 3.87 . 309.10 309.40 13.25 0.98 0.44 18 inch Concretl 0.013 303.83 303.77 3.94 6.97 309.70 309.10 28.89 0.90 0.25 18 inch ConcretE 0.013 303.97 303.90 2.94 5.20 309.40 309.52 18.54 2.75 1.05 18 inch Concretl 0.013 303.48 303.29 6.09 10.76 309.52 279.29 78.06 32.09 33.15 18 inch Concretl 0.013 302.07 276.19 25.55 10.76 316.72 311.40 282.21 1.93 1.99 18 inch Concret 0.013 310.73 305.12 5.67 1.86 311.40 309.40 106.00 2.62 1.11 18 inch Concretl 0.013 304.94 303.77 6.32 1.86 ,. ------------~ .. ----~--L ... Hunsaker 8. Associiltes San Diego, Inc © Haestad Methods, inc. 37 Brookside Road Waterbury, CT 06708 USA +1-203-755-1666 -- - StormCAD v5.5 [5.5,005] Page 1 of 1 - -------- - --- ---Profile Scenario: LA COSTA GREENS -DEVELOPED CONDITIONS: NEIGHSqRHOOD 1.2 (SOUTH) STREET A -MAIN STORM. DRAIN LINE ---~----- Label: 1-117 J --r-------1 [Label: CO-109 Rim: 316.72 ft I Rim: 309.40 ft V 80m> 310: ___ ,~~ _ _ __ __ I ______ ± __ . -~abel: C~-----_____ s.~~~.~~~_1.:.~~_ft_ .. """"" '" " ....... '" "-l'" ... = '''''. '". ~~~:~~:~~ ft A / L~bel: CDS ~" " '. ".". . Rim: 309.52 ft . '''''" "'" '. '" ""'" Sump: 300.81 ft "-' ~ ----\\ \ 1320.00 I I '1315.00 I 310.00 1 -"T".,,,. .. ________ -Label;. ~.1--... --------------__ . __ Up. Invert: 310.2 ft ---------..... -.-.. , 305.00 I On. Invert: 304.1 ft L: 282.2n ft ! Size: 18 irich I· .. · .----.---' j---------------·---g~~~~:~t~f~1---~-----.. ---.. ------,--,.-- I Size: 18 inch I S: 2.62 % ~I---'--'-------------I--.. ---~p.lnvert~~~·I.:tzr----j j n. Invert: 300.81 ft . ~18~4ft f---i----.------------Siz~::1~..)~c:. I I I j ~~~ ... \ \, I I .-,---, 1 300.00 I i 12~OO ----... 1290.00 I Elevation (ft) I. ____________ ._. __ 1' ____ ._. . ---·-----·-~~~~:~~~:!i-~·-· .. -.. -· -... -'\ .... -.----"j 285.00 S: 32.0 % " I Label: HW .. 120 '. \. Rim: 279.29 ft --t -J Size: 181' ch \ 1._ ... ___________________ -. ---------....... ---... -.,-\\--. "1280:~mp: 274.50 ft ~--II --~---~------1------· --j275_00 I I I J i I _~__ _ ____ ,____ .. _______ ._ .. _ ---------------1270.00 0+00 1+00 2+00 3+00 4+00 5+00 Station(ft) h:\stormcad\2352\146\neigh 1.2 .. south.stm 08111106 12:02:1'8 PM Hunsaker & Associates San Diego, Inc © Haestad Methods. Inc. 37 Brookside Road Waterbury. CT 06708 USA +1 .. 203-755 .. 1666 --- StormCAD v5.5 [5.5005] Page 1 of 1 -.------------------Profile Scenario: LA COSTA GREENS -DEVELOPED CONDITIONS: NEIGHBORHOOD 1.2 (SOUTH) STREET A-LATERAL LINE Rim: 309.10 ft Rim: 309.40 ft Label: 1-105 \ / Label: CO-109 Sump: 301.78 ft Sump: 301.32 ft Label: RSR-103 Rim: 309.70 ft Sump: 302.37 ft r------'-----------1--(--_ .. b..~~~tJ:.113, -":q 0.00 I .................... I Rim. 309.1q rr ! ................ ...... .............. .. .. · ..... f. Sump: 301.Y8 ft I '" .' I· .. · ! I ! I I I i I I I I I . -------l 305.00 Elevation (ft) ·-----.1--.---·_-.-.--~-.-.---... --..... -.. I I Label: P-3 i Up. Invert: 301.]78 ft On. Invert: 301.F5 ft L: 13.25 ft 1 Size: 18 inch I S: 0.98 % Label: P-4 Up. Invert: 302.37 ft On. Invert: 302.11 ft L: 28.89 ft Size: 18 inch S: 0.90 % L _____ . --J---l---.--.-----------J 300.00 h:\stormcad\2352\ 146\neigh 1.2-south.stm 08/11/06 12:02:30 PM 0+00 Label: P-5 Up. Invert: 301.78 ft On. Invert: 301.65 ft L: 13.25 ft Size: 18 inch S: 0.98 % 0+50 Station (ft) Hunsaker & Associates San Diego, Inc 1+00 © Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA +1-203-755-1666 Storm CAD v5.5 [5.5005] Page 1 of 1 I I I I I I I I I I I I I I I I I I I LA COSTA GREENS -NEIGHBORHOODS 1.2 & 1.3 CARLSBAD, CA AUGUST 11,2006 ~<'''it~;'~;.:~' ~{; ,",-' , , - ,C'," '~'.':;,: ':.eRQ.,Je;CTPARAI\IIE;r,E~S'\',,~';; '~~,'\'<~':':'':'''~~;:,:,-i;:~;:~<:.:':';~~~:i'Y:f:'>~~-' :.3~lt{~t,~,~,:,,, " " CDS Model PMSU20 15 Q treat 0.7 cfs Q system 10.76 cfs Total Flow in Storm Drain H cds 0.36 ft Required Head Difference to Pro,cess Q treat DIS Pipe Size 1.5 ft DIS Pipe Slope 0.3208 ftlft U/S Pipe Size 1.5 ft U/S Pipe Slope 0.0275 ftlft PMSU Weir Height I 1.00 I ft I PMSU Weir length I 3.5 I ft I :"::7 :;i'" . ,.,,~ . '~i-';~ it", '. ',,' , IiIY.PRAOt:l~iIM~ACr'OFGE)S~UNlrJ\r;$~S;TEM.~FI;;OW,:;·:,;\\i,'i:r;;~,~~'~~~Z~5:f.l.?f)~[~;;;:;?%~',·J;.:', SO Station DIS of CDS 39+97.50 1 Pipe Invert EI dis of CDS 300.81 2 Finished Grade EI@_ CDS 309.52 3 EGl EI dis of CDS 302.79 HGl EI dis of CDS 302.07 Critical Depth in dis Pipe 4 Hcont 0.125 ft Contraction loss from CDS Manhole to dis Pipe 5 EGl EI dis of Baffle 302.91 HGl EI dis of Baffle 302.73 6 Baffle loss 0.50 ft loss Through Baffle Orifice 7 EGl EI dis of Weir 303.41 HGl EI dis of Weir 303.40 8 Hweir 0.14 ft loss From Flow Over Submerged Weir 9 EGl EI u/s of Weir 303.58 HGl EI u/s of Weir 303.53 10 Hexp 0.28 ft Expansion loss from u/s Pipe to CDS Manhole 11 EGl u/s of CDS Unit 303.86 HGl EI u/s of CDS Unit 303.29 SO Station U/S of CDS 40+02.50 Increase in HGL 1.22 ft Freeboard U/S of CDS Unit 6.23 ft 1!f.'Z;i;j,\i;i2::Y;k:'A't,j(;J~,~~:;~~l,)I,:' ~>(·:DRS;T,R~,I\II~~(1f:1~I;~.«t:.I.~~S¥S;r;.E.~~~AE~~?AT~$Y;$,:r:J:M:,~t:;~W,:::i~!}~?-;t'lf~~s\~:W:~~~l.¥gZf.!~;~ft{ length to U/S Manhole/CB Rim Elevation at U/S Manhole/CB Friction Loss to U/S Manhole/CB HGl Ef at U/S Manhole/CB Freeboard at U/S Manhole/CB Loss of Head Due to Contractions For Higher Velocities with H > 1.0 foot: For lower Velocities with H < 1.0 foot: Loss of Head Due to Baffle For Baffie/Orifice (pressure): Loss of Head Due to Weir For Weir (free discharge): For Submerged Weir: 18.54 309.4 0.19 303.48 5.92 Loss of Head Due to Expansion/Enlargement: For All Situations: ft ft ft NO FLOODING OCCURS AT U/S MANHOlElCB, Hcont = (1/c -1)2 * [~/2g] c = 0.582 + 0.0418/(1.1 -r) r = ratio of pipe diameters Hcont = 0.7*(v1 -v2l1 2g Hbaffle = [Q I c Aor]2 I 2g c = 0.6 Hweir = [Q I cl]2i3 c = 3.08 Hweir = Hu/s -Hd/s Hu/s = [Q I Ks * cl]2i3 C = 3.08 Ks = [1 -(Hd/s I Hu/s)1,S]O.3BS Hexp = 1.098 [(v1 -v2) 1.919]/2g SHEET 1 OF2 I I I I I I I I I I- I I I I II ! :1 I I I I TOTAL HEAD LOSSES --~.~~w--------~====~ QJ) EGL AND HGL QSYS ~ @EGL AND HGL SCREEN SUMP Finished Grade EL @ Hcont . @EGL AND HGL CD DIS INV EL OIL BAFFLE CDS IN-LINE PMSU STORM WATER TREATMENT UNIT LOSSES WITH OIL BAFFLE e~' CDSiM 1eCtf\ICL.OQES PATENTED LA COSTA GREENS 1.2 & 1.3 CARLSBAD, CA DATE 5/22/06 DRAWN TJ APPROV. SCALE NTS SHEET 2 OF 2 I I I I I I I I I I I I I I il I I I I DrC;linage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 Chapter 4 HYDRAULIC ANALYSIS 4.2 -Neigh'borhood 1.3 StormCAD Model Output ' AH:ad H:IREPORTS12352\146IA02,doc W.O.2352·1461170 812112008 8:23 AM -,-'-... -----_ .. _------ - Scenario: LA COSTA GREENS -DEVELOPED CONDITIONS: NEIGHBORHOOD 1.3 ?_'\ . ..-//0 RSR-213 1-210 _..--k------..-/.----.. ..- ~rv CO-213 "-------..-._---_ P-3 '-~------'------a Title: La Costa Greens -Neighborhood 1.3 (Developer IPs) h:\storrncadI2352\146\neigh 1.3.stm '"0 j,. HW-204 08/11/06 12:11 :51 PM . © Haestad Methods, Inc. RSR-203 Hunsaker & Associates San Diego, Inc . 37 Brookside Road Waterbury, CT 06708 USA +1-203-755-1666 Project Engineer: AH StormCAD v5.5 [5.5005] Page 1 of 1 -. -_ .. --.------ - --'-Scenario: LA COSTA GREENS -DEVELOPED CONDITIONS: NEIGHBORHOOD 1.3 Combined Pipe\Node Report Label~pstrearrbownstrearrl.Jpstrea~ownstrealPstrea~ownstrea1Lengthronstructe1HYdraUli1section Material Manning1HYdraUli1HYdraUliJAveragetrotai Flow Node! Node ! . Invert Invert Ground Ground (ft) Slope Slope Size n Grade Grade Velocity! (cfs) Elevation Elevation Elevation Elevation (%) (%) Line In Line Out (ft/s) (ft) (ft) (ft) (ft) '(ft) (ft) P-2 11-210 CO-213 P-3 1 RSR-20J' CO-213 P-4 CO-213 HW-204 P-1 RSR-21 1-210 290.74 298.96 289.69 292.85 290.19 301.43 290.19 305.68 286.96 300.30 291.24 310.00 Title: La Costa Greens -Neighborhood 1.3 (Developer IPs) 300.30 55.26 300.30 68.00 291.51 95.30 301.43 80.42 1.00 1.34124 inchl ConcretE! 0.0131 291.841 291.10 6.88 12.901 12.82 124 inchl concretEl 0.0131299.841291.12115.28 2.86 3.34 24 inch ConcretE 0.013 290.88 287.69 10.51 2.00 1.79 18 inch ConcretE 0.013 293.37 291.93 5.77 h:\stormcad\2352\146\neigh 1.3.stm Hunsaker & Associates San Diego, Inc 08/11/06 12:12:07 PM © Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA +1-203-755-1666 9.51 6.21 10.94 1.89 --,- Project Engineer: AH StormCAD v5.5 [5.50051 Page 1 ot'1 ------~--~-~-------Profile Scenario: LA COSTA GREENS -DEVELOPED CONDITIONS: NEIGHBORHOOD 1.3 Label: P-3 Up. Invert: 298.96 ft Dn. Invert: 290.19 ft L: 68.00 ft Size: 24 inch S: 12.90 % STORM DRAIN PROFILE (FROM RISER TO CLEANOUT) Label: RSR-203 Rim: 305.68 ft Sump: 298.96 ft i -1 ?10.00 I·t~-:'~~-----------"----------~------------·I 305 00 ~,I . ~ I , '~ / L<;Ibe~ll: CO-213 " Rim: 300.30 ft ',.. Sum : 289.69 ft -------__ ... ___ ._.,_, _______ . ___ ...1. __ ... __ .... ----_.-... __ .------.. -----J 300.00 Elevation (ft) -0-. ____ --I_ ------.... -.--.. ---.. _-------.-_., 295.00 .. _--. -------_ .. -----.. --, 290.00 ___ I _. ______ ._ .... _____________ _ 0+00 1+00 Station (ft) 285.00 2+00 Tille: La Co;>ta Greens -Neighborhood 1.3 (Developer IPs) h:\storrncad\2352\146\neigh 1.3.stm Hunsaker & Associates San Diego,lnc 08/11/06 12:12:29 PM © Haestad Methods, Inc. 37 Brookside Road Waterbury. CT 06708 USA .j.1-203-755-1666 Project Engineer:' AH Storm CAD v5.5[5.5005] Page 1 of 1 ___ ,_-_---1-___ _ - - ---Profile Scenario: LA COSTA GREENS -DEVELOPED CONDITIONS: NEIGHBORHOOD 1.3 Label: RSR·213 Rim: 310.00 ft . Sump: 292.85 ft STORM DRAIN PROFILE (FROM RISER TC?. HEADWALL) --------_.--.. T--------.. -... ---. ---.-----. -'---.. ---.. -.... , 310.00 I -------~--------____ _l_ .. -... --.---·1 305.00 I ....... " .. ""t- Label: 1·210 Rim: 301.43 ft Sump: 290.74 ft Label: CO·213 Rim: 300.30 ft I Sump: 289.69 ft __ . ______ , 300.00 _."._~ __ t-__ _____ M. _______ • _. __ ,,, • .-------_.-._._._-_._---------.--.-._---_ .. "._------.-.-,~----- 0+00 , " '. Label: P-2 " , , " Label: HW·204 Rim: 291.51 ft Sump: 286.92 ft I Up Invert: 290.74·ft Label: P·1 85 ft Dn: Invert: 290.19 ft Up Invert: 292.. L' 55 26 ft Dn; Invert: 291.24 ft L Size:'24 inch I "--Label: P-~ 289 69ft ___ . __ . ________ .1 285.00 c.8O.42 , 8: 1.00 % _--.!l~ '''''"_" _ .___. 3+00 Size: 18 Inch __ . ____ .... __ ._ ____ Dn.lnvert. 286.96 ft 8:2.00% ---2<011 l:95.30ft ----... Size: 24 Inch 1+00 Station (ft) S:2.86% Title: La Costa Greens -Neighborhood 1.3 (Developer IPs) h:\storrncad\2352\146\neigh 1.3.stm Hunsaker & Associates San Diego, Inc 08/11/06 12:12:45 PM © Haestad Methods. Inc. 37 Brookside Road Waterbury. CT 06708 USA +1-203-755-1666 Elevation (ft) Project J;::ngineer: AH StormCAD v5.5 [5.5005] Page 1 of 1 I~ I, I :1, II' I : II I: I v I I ': I' I' I, I: I: ,I I I, I II I I I I I I I I I I I I I I I I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 5 INLET SIZING AH:ad H:IREPORTSI235211461A02.doc W.O.2352·1461170 812112005 8:23 AM I I I I I I I I I I I I I I I I I !I I CURB INLET SIZING LA COSTA GREENS· NEIGHBORHOODS 1.2 AND 1.3 NEIGHBORHOOD 1'.3 Street Surface Inlet Node SIope1 Flo~ Type 10 S (%) Q (cfs) On-Grade 210 4.88% 7.9 1 From street profiles in Improvement Plans 2 From AES ouput Gutter Depression a (ft) 0.33 3 From Manning's Equation: Q = (1.49/n)*A*S112*R213 Flow Required Depth3 Length of y (ft) Opening4 (ft) 0.36 18.9 The hydraulic radius, R, and area, A, are expressed as a function of the flow depth, y. Typical cross-section of a Type G gutter is used for the analysis. 4 Per City of Carlsbad Standards From Equation: Q = O.7L(a+y)312 5 Length shown on plans (Required Length of Opening + 1 foot) NEIGHBORHOOD 1.2 Street Surface Inlet Node SIope1 Flo~ Type 10 S (%) Q (cfs) Sump 117 N\A 1.9 Sump 105 N\A 1.9 Sump 113 N\A 3.9 1 From street profiles in Improvement Plans 2 From AES Model ouput Gutter Depression a (tt) N\A- N\A N\A 3 Per City of Carlsbad Standards From Ratio: Q/l = 2 5 Length shown on plans (Required Length of Opening + 1 foot) Flow Required Depth Length of y (ft) Opening3 (tt). N\A 0.9 N\A 0.9 N\A 1.9 Use Length 5 (ft) 20 Use Length 5 (ft) 5 5 5 H:\EXCEL \2352\146\1NLETS-CARLSJ;3AD.x1s 8/11/2006 I .1 I' I :1 I I 1 ,I I I 'I I, I I I I I I VI I I I I I I I I I I I I I I I I I II I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1_2 & 1.3 CHAPTER 6 AC BERM OPENING DESIGN AH:~d H:IREPORTS\235211461A02.doc W.O.2352-146/170 812112006 8:23 A"1 I I I I I I I I I I I I I I, I I II i I I 8/11/2006 OPENING LENGTH DETERMINATION LA COSTA GREENS -NEIGHBORHOODS 1.2 AND 1.3 Per City of Carlsbad Standards for On-Grade Openings: , Where: Q = O.7L(a + y)3/2 Q = Runoff (cfs) a = Depth of Depression of Flowline (ft) y = Depth of Flow (ft) L = Length of Clear Opening (ft) Determine Opening Length in AC berm: Node Location: Node 218 Q= 0.18 cfs* (See 85th Percentile Peak Flow Determination spreadsheet) a= 0.00 ftA y= 0.27 ft (See FlowMaster ouput) L= 1.83 ft L= 1.9 ft Notes: * The length of the AC berm opening is designed to convey the first flush runoff only into the the grassy swale. A Unlike gutters, the AC berm does not have a flowline depression. H:\EXCEL\2352\146\AC Berm Opening.xls I I I I I I I I I I I I I I I I I I I Cross Section for Street A XSect Friction Method Solve For Manning Formula Normal Depth Channel Slope No"rmal Depth Discharge c 0 i :> .!f! w 0.00 . . . . . : ~ .. · .... *······ .. ··~· .. · .. t ...... •••• ........ ,·· .. • .. • .... ·····*· .. · .. · .... · .. · .. 1 .. • .. ••• .... • .. • .. 1· .. "··".·· 0.70 ..... J ............ ..1. ........... _ .... 1... ............ j ...... -.. ..1. ............. I... .. .. 0.50 0.40 0.00. ~:;==+=:~t::=':l~::::t~-:=I:= 0.30 ·· .. ····1··············· .1' ........ "..... -·· .. ·· .... ·····l··· .. ··· .. ·· .. ···r~'"·· .. ··· .. ··r· to •• 0 : : . 0.20 '0.10 0.00 -0.10 ··" ......................... , ...... • •• • .... •• .. 1· ... •••• .. • .. ••• • ... •• ......... ·I ........ " ...... "t ....... . i I ~ . ! i ~ -•... " ) ..........• ···1······· •...•. ~.-............ -{..... ......... •·······• __ ·····t· ._, .. . _=t=t=L:~t~I~=~=: -0.20 . f i ~ ~ ~ ! 0..00 ' &.us 1 0+10 ' 0+'15 1 0+20 ' 0+25 ' 0+30 station 2.00 % 0.27 ft 6.64 cfs Bentley Systems, Inc. Haestad Methods Solution Center Bentley FlowMaster [08.01.066.00] 8/11/200612:20:38 PM 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 Page 1 of 1 I I I I I I I I I I I I I I I I I I I 8/11/2006 85th PERCENTILE PEAK FLOW DETERMINATION Modified Rational Method -Effective for Watersheds < 1.0mi2 Project Name: Work Order: Jurisdiction: BMP Location La Costa Greens -Neighborhoods 1.2 & 1.3 2352-141 City of Carlsbad Grassy Swale @ Node 205 (This flow enters Grassy Swale from AC Berm Opening) Developed Drainage Area = Natural Drainage Area = Total Drainage Area to BMP = Dev. Area Percent Impervious = Nat. Area Percent Impervious = Overall Percent Impervious = Dev. Area Runoff Coefficient = Nat. Area Runoff Coefficient = Runoff Coefficient = RATIONAL METHOD RESULTS Q = CIA where: Q = C= 1= A= Using the Total Drainage Area: C= 1= A= Q= 1.00 acres 0.00 acres 1.00 acres 100.0 % 0 % 100.0 % 0.90 0.45 0.90 85th Percentile Peak Flow (cfs) Runoff Coefficient Rainfall Intensity (0.2 inch/how per RWQCB mandate). Drainage Area (acres) 0.90 0.2 inch/hour 1.00 acres· 0.18 cfs* * NOTE: Corresponds to a portion of the first-flush runoff into the grassy swale, generated by Private Drive "A" and the proposed RV Storage site only. This flow enetrs the grassy swale throught he AC berm opening. The AC berm opening was sized to only allow this flow to enter. H:\EXCEL\2352\146\85th Flow.xls I I I I I I I I I I I I I I I I I I I 8/1112006 WEIGHTED RUNOFF COEFFICIENT CALCULATIONS FOR GRASSY SWALE BMP @ NODE 205 La Costa Greens -Neighborhoods 1.2 & 1.3 U/S DIS NODE NODE 201 202 202 205 206 207 207 208 209 208 208 205 TOTALA= WEIGHTEDC= IMPERVIOUS = A (acres) 0.07 0.38 0.06 0.27 0.21 0.01 1.00 ac 0.90 100.0 % 7 of 10 IMPERVIOUS C (%) 0.90 100 0.90 100 0.90 100 0.90 100 0.90 100 0.90 100 H:\t=XCEL\235.2\146\85th Flow.xls :1 I I I I I .1 I I I 1 I ·1 1 ·1 I; I ! I If VII I I I I I I I il I I I I I I I I jl I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 7 DESIL T BASIN DESIGN 7.1 -100-Year Mass-Grade Condition AES Model Output (for Riser and Desilt Basin Design Only) AH:ad H:IREPORTS\23521146\A02.doc W.0.2352·1461170 812112006 8:23 AM I I I I I I I I I I I I I I I I I **************************************************************************** RATIONAL METHOD HYDROLOGY COMPUTER PROGRAM PACKAGE Reference: SAN DIEGO COUNTY FLOOD CONTROL DISTRICT 2003,1985,1981 HYDROLOGY MANUAL (c) Copyright 1982-2003 Advanced Engineering Software (aes) Ver. 1.5A Release Date: 01/01/2003 License ID 1239 Analysis prepared by: HUNSAKER & ASSOCIATES -SAN DIEGO 10179 Huennekens Street San Diego, Ca. 92121 (858) 558-4500 ************************** DESCRIPTION OF STUDY ************************** * LA COSTA GREENS -NEIGHBORHOODS 1.2 AND 1.3 * * 100-YEAR MASS-GRADED CONDITION HYDROLOGIC ANALYSIS INTO DESILT BASINS * * (FOR RISER AND DESILT BASIN DESIGN ONLY) * ************************************************************************** FILE NAME: H:\AES2003\2352\146\INT100MG.DAT TIME/DATE OF STUDY: 10:57 08/11/2006 USER SPEGIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION: 2003 SAN DIEGO MANUAL CRITERIA USER SPECIFIED STORM EVENT(YEAR) = 100.00 6-HOUR DURATION PRECIPITATION (INCHES) = 2.800 SPECIFIED MINIMUM PIPE SIZE(INCH) = 18.00 SPECIFIED PERCENT OF GRADIENTS(DEClMAL) TO USE FOR FRICTION SLOPE = 0.90 SAN DIEGO HYDROLOGY MANUAL "C"-VALUES USED FOR RATIONAL METHOD NOTE: USE MODIFIED RATIONAL METHOD PROCEDURES FOR CONFLUENCE ANALYSIS *USER-DEFlNED STREET-SECTIONS FOR COUPLED PIPEFLOW AND STREETFLOW MODEL* HALF-CROWN TO STREET-CROSSFALL: CURB GUTTER-GEOMETRIES: MANNING WIDTH CROSSFALL IN-/ OUT-/PARK-HEIGHT WIDTH LIP HIKE FACTOR NO. (FT) (FT) SIDE / SIDE/ WAY (FT) (FT) (FT) (FT) (n) 1 2 20.0 15.0 15.0 10.0 0.020/0.020/ 0.020/0.020/ --- 0.50 0.50 1.50 0.0313 0.125 0.0150 1.50 0.0313 0.125 0.0150 GLOBAL STREET FLOW-DEPTH CONSTRAINTS: 1. Relative Flow-Depth = 0.00 FEET as (Maximum Allowable Street F~ow Depth) -(Top-of-CUrb) 2. (Depth) * (Velocity) Constraint = 4.0 (FT*FT/S) *SIZE PIPE WITH A FLOW CAPACITY GREATER THAN OR EQUAL TO THE UPSTREAM TRIBUTARY PIPE.* +--------------------------------------------------------------------------+ I I I BEGIN ANALYSIS INTO DESILT BASIN #1 (MASS-GRADED LAND TYPE) I I I +--------------------------------------------------------------------------+ **************************************************************************** FLOW PROCESS FROM NODE 101.00 TO NODE 102.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< ============================================================================ *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .5500 S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET) = 70.00 uPSTREAM ELEVATION(FEET) = 317.00 DOWNSTREAM ELEVATION(FEET) = 315.60 ELEVATION DIFFERENCE(FEET) = 1.40 SUBAREA OVERLAND TIME OF FLOW(MIN.) = 6.574 100 YEAR RAINFALL INTENSITY (INCH/HOUR) 6.183 SUBAREA RUNOFF (CFS) 0 .75 TOTAL AREA (ACRES) = 0.22 TOTAL RUNOFF (CFS) 0.75 **************************************************************************** FLOW PROCESS FROM NODE 102.00 TO NODE 103.00 IS CODE = 51 »»>COMPUTE TRAPEZOIDAL CHANNEL FLOW««< »»>TRAVELTIME THRU SUEAREA (EXISTING ELEMENT)««< ELEVATION DATA: UPSTREAM (FEET) = CHANNEL LENGTH THRU SUBAREA (FEET) = 315.60 DOWNSTREAM (FEET) 122.20 CHANNEL SLOPE = 306.80 0.0720 1 I I I I I I I I I I I I I I I I I I CHANNEL BASE{FEET) 0.00 "Z" FACTOR = 99.990 MANNING'S FACTOR = 0.030 MAXIMUM DEPTH{FEET) = 0.50 100 YEAR RAINFALL INTENSITY (INCH/HOUR) = 5.554 *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .5500 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW{CFS) 1.35 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY{FEET/SEC.) 1.71 AVERAGE FLOW DEPTH{FEET) 0.09 TRAVEL TIME{MIN.) 1.19 TC{MIN.) = 7.76 SUBAREA AREA{ACRES) 0.39 SUBAREA RUNOFF (CFS) 1.19 AREA-AVERAGE RUNOFF COEFFICIENT 0.550 TOTAL AREA{ACRES) = 0.61 PEAK FLOW RATE{CFS) 1.86 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH (FEET) = 0.10 FLOW VELOCITY (FEET/SEC.) 1.79 LONGEST FLOWPATH FROM NODE 101.00 TO NODE 103.00 = 192.20 FEET. **************************************************************************** FLOW PROCESS FROM NODE 104.00 TO NODE 103.00 IS CODE = 81 »»>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< 100 YEAR RAINFALL INTENSITY{INCH/HOUR) = 5.554 *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .5500 S.C.S. CURVE NUMBER (AMC II) = 0 AREA-AVERAGE RUNOFF COEFFICIENT = 0.5500 SUBAREA AREA{ACRES) 0.20 SUBAREA RUNOFF{CFS) TOTAL AREA{ACRES) 0.81 TOTAL RUNOFF{CFS) = TC{MIN.) = 7.76 0.61 2.47 +--------------------------------------------------------------------------+ I END ANALYSIS TO DESILT NASIN #1 (MASS-GRADED LAND TYPE) I I I I BEGIN ANALYSIS TO DESILT BASIN #2 (MASS-GRADED LAND TYPE) I +--------------------------------------------------------------------------+ **************************************************************************** FLOW PROCESS FROM NODE 211. 00 TO NODE 212.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< ============================================================================ *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .5500 S.C.S. CURVE NUMBER (AMC II) = 0 INITiAL SUBAREA FLOW-LENGTH{FEET) = 65.00 UPSTREAM ELEVATION{FEET) = 313.00 DOWNSTREAM ELEVATION{FEET) = 312.30 ELEVATION DIFFERENCE{FEET) = 0.70 SUBAREA OVERLAND TIME OF FLOW (MIN.) = 7 . 787 100 YEAR RAINFALL INTENSITY{INCH/HOUR) 5.544 SUBAREA RUNOFF{CFS) 0.18 TOTAL AREA{ACRES) = 0.06 TOTAL RUNOFF{CFS) 0.18 **************************************************************************** FLOW PROCESS FROM NODE 212.00 TO NODE 213.00 IS CODE = 51 »»>COMPUTE TRAPEZOIDAL CHANNEL FLOW««< »»>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT) ««< ============================================================================ ELEVATION DATA: UPSTREAM (FEET) = 312.30 DOWNSTREAM (FEET) 310.00 CHANNEL LENGTH THRU SUBAREA{FEET) = 98.30 CHANNEL SLOPE 0.0234 CHANNEL BASE{FEET) 0.00 "Z" FACTOR = 99.990 MANNING'S FACTOR = 0.030 MAXIMUM DEPTH (FEET) = 0.50 100 YEAR RAINFALL INTENSITY{INCH/HOUR) = 4.867 *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .5500 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW{CFS) 0.71 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY{FEET/SEC.) 0.94 AVERAGE FLOW DEPTH{FEET) 0.09 TRAVEL TIME (MIN.) 1.74 Tc{MIN.) = 9.53 SUBAREA AREA{ACRES) 0.39 SUBAREA RUNOFF{CFS) 1.04 AREA-AVERAGE RUNOFF COEFFICIENT 0.550 TOTAL AREA{ACRES) = 0.45 PEAK FLOW RATE{CFS) 1.20 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH (FEET) = 0.10 -FLOW VELOCITY{FEET/SEC.) 1.11 LONGEST FLOWPATH FROM NODE 211.00 TO NODE 213.00 = 163.30 FEET. 2 I I I I I I I I I I I I I I I I I I I +--------------------------------------------------------------------------+ I END ANALYSIS TO DESILT BASIN #2 (MASS-GRADED LAND TYPE) I I I I BEGIN ANALYSIS TO EXISTING DESILT BASIN #3 (MASS-GRADED LAND TYPE) I +--------------------------------------------------------------------------+ **************************************************************************** FLOW PROCESS FROM NODE 215.00 TO NODE 216.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< ============================================================================ *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .5500 S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET) = 65.00 UPSTREAM ELEVATION(FEET) = 322.00 DOWNSTREAM ELEVATION(FEET) = 321.40 ELEVATION DIFFERENCE(FEET) = 0.60 SUBAREA OVERLAND TIME OF FLOW(MIN.) = 8.051 WARNING: INITIAL SUBAREA FLOW PATH LENGTH IS GREATER THAN THE MAXIMUM OVERLAND FLOW LENGTH = 62.69 (Reference: Table 3-1B of Hydrology Manual) THE MAXIMUM OVERLAND FLOW LENGTH IS USED IN Tc CALCULATION! 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.426 SUBAREA RUNOFF(CFS) 0.21 TOTAL AREA(ACRES) = 0.07 TOTAL RUNOFF(CFS) 0.21 **************************************************************************** FLOW PROCESS FROM NODE 216.00 TO NODE 217.00 IS CODE = 51 »»>COMPUTE TRAPEZOIDAL CHANNEL FLOW««< »»>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT) ««< ============================================================================ ELEVATION DATA: UPSTREAM (FEET) = 321.40 DOWNSTREAM (FEET) 320.90 CHANNEL LENGTH THRU SUBAREA(FEET) = 194.80 CHANNEL SLOPE 0.0026 CHANNEL BASE(FEET) 0.00 "Z" FACTOR = 99.990 MANNING'S FACTOR = 0.030 MAXIMUM DEPTH(FEET) = 0.50 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 3.486 *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .5500 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) 0.72 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) 0.41 AVERAGE FLOW DEPTH(FEET) 0.13 TRAVEL TIME(MIN.) 7.94 Tc(MIN.) = 15.99 SUBAREA AREA(ACRES) 0.52 SUBAREA RUNOFF(CFS) 1.00 AREA-AVERAGE RUNOFF COEFFICIENT 0.550 TOTAL AREA(ACRES) = 0.59 PEAK FLOW RATE(CFS) = 1.13 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH (FEET) = 0.16 FLOW VELOCITY.(FEET/SEC.) LONGEST FLOWPATH FROM NODE 215.00 TO NODE 0.46 217.00 = 259.80 FEET. **************************************************************************** FLOW PROCESS FROM NODE 217.00 TO NODE 218.00 IS CODE = 51 »»>COMPUTE TRAPEZOIDAL CHANNEL FLOW««< »»>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT) ««< ============================================================================ ELEVATION DATA: UPSTREAM (FEET) = 320.90 DOWNSTREAM (FEET) CHANNEL LENGTH THRU SUBAREA(FEET) = 465.50 CHANNEL SLOPE CHANNEL BASE(FEET) 0.00 "Z" FACTOR = 99.990 MANNING'S FACTOR = 0.030 MAXIMUM DEPTH(FEET) = 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 2.722 *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .5500 S.C.S. CURVE NUMBER (AMC II) = 0 0.50 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) AVERAGE FLOW DEPTH(FEET) 0.13 TRAVEL TIME(MIN.) 1.67 1.04 Tc(MIN.) = 23.46· 0.72 SUBAREA AREA (ACRES) AREA-AVERAGE RUNOFF COEFFICIENT SUBAREA RUNOFF (CFS) 0.550 7.47 TOTAL AREA(ACRES) = 1.31 PEAK FLOW RATE(CFS) = END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH (FEET) = 0.13 FLOW VELOCITY(FEET/SEC.) 1.08 313.20 0.0165 1.08 1.96 LONGEST FLOWPATH FROM NODE 215.00 TO NODE 218.00 = 725.30 FEET. **************************************************************************** FLOW PROCESS FROM NODE 218.00 TO NODE 218.00 IS CODE = 1 3 I I I I I I I I I I I I I I I I I I I »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 1 ARE: TIME OF CONCENTRATION(MIN.) 23.46 RAINFALL INTENSITY (INCH/HR) = 2 .72 TOTAL STREAM AREA(ACRES) = 1.31 PEAK FLOW RATE(CFS) AT CONFLUENCE = 1.96 **************************************************************************** FLOW PROCESS FROM NODE 2l8.00 TO NODE 218.00 IS CODE = 7 »»>USER SPECIFIED HYDROLOGY INFORMATION AT NODE««< USER-SPECIFIED VALUES ARE AS FOLLOWS: TC(MIN) = 5.00 RAIN INTENSITY(INCH/HOUR) = 7.38 TOTAL AREA(ACRES) = 0.01 TOTAL RUNOFF(CFS) = 0.18 *********************************************~****************************** FLOW PROCESS FROM NODE 218.00 TO NODE 218.00 IS CODE = »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< »»>AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES««< 1 ============================================================================ TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 2 ARE: TIME OF CONCENTRATION(MIN.) 5.00 RAINFALL INTENSITY (INCH/HR) = 7.38 TOTAL STREAM AREA (ACRES) = 0.01 PEAK FLOW RATE(CFS) AT CONFLUENCE = 0.l8 ** CONFLUENCE DATA ** STREAM RUNOFF Tc INTENSITY NUMBER (CFS) (MIN.) (INCH/HOUR) 1 1.96 23.46 2.722 2 0.l8 5.00 7.377 AREA (ACRE) 1.3l O.Ol RAINFALL INTENSITY AND TIME OF CONCENTRATION RATIO CONFLUENCE FORMULA USED FOR 2 STREAMS. ** PEAK FLOW RATE TABLE ** STREAM RUNOFF Tc INTENSITY NUMBER (CFS) (MIN.) (INCH/HOUR) 1 0.60 5.00 7.377 2 2.03 23.46 2.722 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE(CFS) 2.03 Tc(MIN.) = 23.46 TOTAL AREA(ACRES) = l.32 LONGEST FLOWPATH FROM NODE 215.00 TO NODE 2l8.00 725.30 FEET. **************************************************************************** FLOW PROCESS FROM NODE 2l8.00 TO NODE 219.00 IS CODE = 5l »»>COMPUTE TRAPEZOIDAL CHANNEL FLOW««< »»>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT)««< ============================================================================ ELEVATION DATA: UPSTREAM (FEET) = 313.20 DOWNSTREAM (FEET) 3ll.80 CHANNEL LENGTH THRU SUBAREA(FEET) = 137.00 CHANNEL SLOPE 0.0102 CHANNEL BASE (FEET) 4.00 "Z" FACTOR = 3.000 MANNING'S FACTOR = 0.250 MAXIMUM DEPTH (FEET) = 1.00 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 2.386 *USER SPECIFIED (SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .5500 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) 2.51 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY (FEET/SEC.) 0.43 AVERAGE FLOW DEPTH(FEET) 0.88 TRAVEL TIME(MIN.) 5.31 Tc(MIN.) = 28.77 SUBAREA AREA (ACRES) 0.74 SUBAREA RUNOFF (CFS) 0.97 AREA-AVERAGE RUNOFF COEFFICIENT 0.559 TOTAL AREA(ACRES) = 2.06 PEAK FLOW RATE(CFS) 2.75 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH (FEET) = 0.92 FLOW VELOCITY(FEET/SEC.) 0.44 219.00 = LONGEST FLOWPATH FROM NODE 215.00 TO NODE 862.30 FEET. **************************************************************************** FLOW PROCESS FROM NODE 219.00 TO NODE 203.00 IS CODE = 51 4 I I I I I I ,I I I I I I I I I I I I »»>COMPUTE TRAPEZOIDAL CHANNEL FLOW««< »»>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT) ««< ELEVATION DATA: UPSTREAM (FEET) = 311.80 DOWNSTREAM (FEET) 307.10 CHANNEL LENGTH THRU SUBAREA(FEET) = 200.10 CHANNEL SLOPE 0.0235 CHANNEL BASE(FEET) 0.00 "Z" FACTOR = 99.990 MANNING'S FACTOR = 0.030 MAXIMUM DEPTH(FEET) = 0.50 100 YEAR RAINFALL INTENSITY (INCH/HOUR) = 2.264 *USER,SPECIFIED(SUBAREA) : USER-SPECIFIED RUNOFF COEFFICIENT = .5500 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) 3.62 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY (FEET/SEC.) 1.36 AVERAGE FLOW DEPTH(FEET) 0.16 TRAVEL TIME(MIN.) 2.45 Tc(MIN.) = 31.22 SUBAREA AREA(ACRES) 1.40 SUBAREA RUNOFF (CFS) 1.74 -AREA-AVERAGE RUNOFF COEFFICIENT d .555 TOTAL AREA(ACRES) = 3.46 PEAK FLOW RATE(CFS) = 4.35 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH (FEET) = 0.17 FLOW VELOCITY(FEET/SEC.) 1.49 LONGEST FLOWPATH FROM NODE 215.00 TO NODE 203.00 = 1062.40 FEET. +--------------------------------------------------------------------------+ I I I END ANALYSIS TO EXISTING DESILT BASIN #3 (MASS-GRADED LAND TYPE) I I I +--------------------------------------------------------------------------+ ============================================================================ END OF STUDY SUMMARY: TOTAL AREA(ACRES) PEAK FLOW RATE(CFS) 3.46 TC(MIN.) = 4.35 31.22 ============================================================================ END OF RATIONAL METHOD ANALYSIS 5 I I I I I I I I I I I I I I 'I I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 7· DESIL T BASIN DESIGN 7.2 -Riser and Desilt Basin Calculatio-ns AH:ad H:IREPORTSI23521146\A02.dac W.O.2352-146J170 -6121/2006 8:23 AM I I I I I I I I I I I I I I I I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 7 DESIL T BASIN DESIGN 7.2 -Riser and Desilt Basin Calculations "Proposed Desilt Basin #1" AH:ad H:IREPORTSI235211461A02.doc W.O.2352·146/170 8/2112006 8:23 AM I I I I I I I I I I I I I I I I I I I DESIL T BASIN DESIGN LA COSTA GREENS -NEIGHBORHOOPS 1.2 AND 1.3 PROPOSED DESIL T BASIN #1 -NEIGHBORHOOD 1.2 Per Optiori 2, Part 8 of Section A of the State Water Resources Control Board Order No. 99-0B-DWQ, sediment basins shall, at a minimum, be designed as follows: Sediment basins, as measured from the bottom of the basin to the principle outlet, shall have at least capacity equivalent to 3,600 cubic feet of storage per acre draining into the sediment basin. The length of the basin shall be more than twice the width of the basin. The length is determined by measuring the distance between the inlet and the outlet; and the depth must not be less than three feet nor greater than five feet for safety reasons and for maximum effiCiency. - GRADED AREA TO BASIN 100-YEAR PEAK FLOW TO BASIN ------------> ~acres ------------> ~cfs REQUIRED STORAGE CAPACITY BELOW PRINCIPLE OUTLET ELEV. BOTTOM OF BASIN ELEVATION ------------> RISER/PRINCIPLE SPILLWAY EL. -------------> DEPTH BELOW PRINCIPLE OUTLET IDESIGN BASIN BOTTOM WIDTH 1-------------> DESIGN BASIN BOTTOM LENGTH DESIGN STORAGE CAPACITY "BELOW PRINCIPLE OUTLET ELEV. 1100-YEAR HW OVER RISER 1------------> 100-YEARWSE OVER RISER FREEBOARD ABOVE -----------> 100-YEAR WSE ITOP OF BASIN ELEVATION 1-------------> 2916 fe 108 CY 0.067 acre-ft. ~feet ~feet 3.0 Ifeet BElfeet N/A feet 2920 ft3 108 CY 0.067 acre-ft. ~feet 310.0 feet 1.0 1ft. 311.0 Ifeet (From AES Model Output and Hydro Map) (From AES Model Output and Hydro Map) (From Grading Plans) (From Grading Plans) (3 <= Depth <= 5 feet) (Length> 2 * Width) (From Stage-Storage spreadsheet) (From Riser Design Spreadsheet) (From Grading Plans) * Emergency spillway crest elevation shall be set at or above 100-Year WSE. The emergency' spillway shall be sized to convey the 100-year runoff assuming 100% clogging of principle spillway. FOR BROAD-CRESTED EMERGENCY SPILLWAY WEIRS: If the CREST ELEVATION = ----------> Then the Spillway Opening Must Be = 8/11/2006 I:J'EDfeet ~feet lof7 H:\EXCEL\2352\146\DESILT BASIN-OPTION 2.xls I I I I I I I I I I I I I I I I I ~ I I RISER DESIGN FOR DESIL T .BASIN LA COSTA GREENS -NEIGHBORHOODS 1.2 AND 1.3 Proposed Desilt Basin #1 -Neighborhood 1.2 Weir Formula for Orifices & Short Tubes (free & submerged): Q = 0.85*CA(2gH) 1/2 Q = 0.85*0.6A(64.32H)1/2 Q = 4.1A(H)1/2 Therefore, H = (QI4.1A) 2 (Equation 1) Weir Formula for riser acting as straight weir: Q = CLH2I3 Therefore, H = (QI3.3L) 213 (Equation 2) Node 103 : where: 0.85 is a reduction factor for trash rack (corresponding to a 15% reduction for the grate) C = Orifice Coefficient = 0.6 from Table 4-10, Kings Handbook A = Cross-Sectional Area of Orifice (fe) g = Gravitational Constant = 32.16 ft/s2 H = Head above Top of Riser (ft) where: C = Weir Coefficinet = .3.3 from Eqn. 5-40, Kings Handbook L = Length of Weir (ft) H = Head above Top of Riser (ft) Q100 = 2.38 cfs Riser d = 30 in Thus, A = 4.909 sq. ft. ---.. ~ H = 0.01 ft. (Eqn. 1) (Eqn.2) L = 7.854 ft. ~ H = 0.20 ft. Therefore: I H = 0.20 ft. I 8/11/2006 20f7 H:\EXCEL\2352\146\RISER DESIGN.xls I I- I- I I I I I I I I I I I I I II I I STAGE·STORAGE TABLE LA COSTA GREENS -NEIGHBORHOODS 1.2 AND 1.3 Proposed Desilt Basin #1 -Neighborhood 1.2 Elevation Elevation Total Elevation Area Total Volume eft) Difference eft) Difference eft) (acres) (acre-ft.) 306.8 0.013 0.000 307.0 0.014 0·003 0.20 0.20 308.0 0.020 0.020 1.00 1.20 309.0 0.027 0.O4~ 1.00 2.20 309.8 * 0.033 0.067 0.80 3.00 310.0 0.034 0.074 0.20 3.20 311.0 0.042 0.112 _ 1.00 4.20 *Note: This elevation corresponds to the elevation at the top of the riser. :. Vreq = 0.067 acre-ft ~ Vrisertop = 0.067 acre-ft 8/11/2006 30f7 H:\EXCEL\2352\146\STAGE STORAGE.xls I I I I I I' I ·1 I I I I I I I ,I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 7 DESIL T BASIN DESIGN 7.2 -Riser and Desilt Basin Calculations "Proposed Desilt Basin #2" AH:ad H:IREPORTS123S2\1461A02.doc W.O.23S2-146/170 6121/2006 6:23 AM I I I, I I I I I ., ,I I I I I I I I I I DESIL T BASIN DESIGN LA COSTA GREENS -NEIGHBORHOODS 1.2 AND 1.3 PROPOSED DESIL T BASIN #2 -NEIGHBORHOOD 1.3· Per Option 2, Part B of Section A of the State Water Resources Control Board Order NO. 99-0B-DWQ, sediment basins shall, at a minimum, be designed as follows: Sediment basins, as measured from the bottom of the basin to the principle outlet, shall have at least capacity equivalent to 3,600 cubic feet of storage per acre draining into the sediment basin. The length of the basin shall be more than twice the width of the basin. The length is determined by measuring the distance between the inlet and the outlet; and the depth must not be less than three feet nor greater than five feet for safety reasons and for maximum efficiency. GRADED AREA TO BASIN 100-YEAR PEAK FLOW TO BASIN REQUIRED STORAGE CAPACITY BELOW PRINCIPLE OUTLET ELEV. BOTTOM OF BASIN ELEVATION RISER/PRINCIPLE SPILLWAY EL. DEPTH BELOW PRINCIPLE OUTLET -----------> ~acres ------------> ~cfs -------------> ------------> 1620 te 60 CY 0.04 acre-ft. ~feet ~feet 3.0 Ifeet IDESIGN BASIN BOTTOM WIDTH 1-----------> . ~feet DESIGN BASIN BOTTOM LENGTH c:J:I:Jfeet DESIGN STORAGE CAPACITY BELOW PRINCIPLE OUTLET ELEV. 2331 ft3 86 CY 0.05 acre-ft. 1100-YEAR HW OVER RISER 1------------> CIT:Jteet "1"'!'O"!'"O-"'Y~EA"'R~W~S~E"'O~V~E~R"'R~IS~E~R~-"" ~feet FREEBOARD ABOVE . 100-YEAR WSE -------------> a.;IT;..;O;.;.P_O;;.;F_B;.;A..;.S;.;,IN~E,;;,LE;;.V.;.;,A.;.;T..;.IO;;.;N~_ ...... I------------> 1.0 1ft. 310.0 Iteet (From AES-99 Output and Hydro Map) (From AES-99 OutJ)ut and Hydro Map) (From Grading Plans) (From Grading Plans) (3 <= Depth <= 5 feet) (Length> 2 * Width) (From Riser Design Spreadsheet) (From Grading Plans) * Emergency spillway crest elevation shall be set at or above 100-Year WSE. The emergency spillway shall be sized to convey the 1 ~O-year runoff assuming 100% clogging of principle spillway. FOR BROAD-CRESTED EMERGENCY SPILLWAY WEIRS: Ifthe CREST ELEVATION = ---------> Then the Spillway Opening Must Be = 8/11/2006 ~feet ~feet 40f7 H:\EXCEL\2352\146\DESIL T BASIN-OPTION 2.xls I I I I I I I I I I I I I I I I I I I RISER DESIGN FOR DESIL T BASIN LA COSTA GREENS -NEIGHBORHOODS 1.2 AND 1.3 Proposed Desilt Basin #2 -Neighborhood 1.3 Weir Formula for Orifices & Short Tubes (free & submerged): o = 0.85*CA(2gH) 1/2 o = 0.85*0.6A(64.32H) 1/2 o = 4.1A(H) 1/2 Therefore, H = (Q/4.1A) 2 (Equation 1) Weir Formula for riser acting as straight weir: 0= CLH2I3 Therefore, H = (Q/3.3L) 213 (Equation 2) Node 213 : where: 0.85 is a reduction factor for trash rack (corresponding to a 15% reduction for the grate) C = Orifice Coefficient where: = 0.6 from Table 4-10, Kings Handbook A = Cross-Sectional Area of Orifice (ff) g = Gravitational Constant = 32.16 ftIs2 H = Head above Top of Riser (ft) C = Weir Coefficinet = 3.3 from Eqn. 5-40, Kings Handbook L = Length of Weir (ft) H = Head above Top of Riser (ft) 0 100 = 1.20 cfs Riser d = 30 in Thus, A = 4.909 sq. ft. ---.... H = 0.00 ft. (Eqn. 1) (Eqn.2) L = 7.854 ft. • H = 0.13 ft. Therefore: IH= 0.13 ft. I 8/11/2006 5 of? H:\EXCEL\2352\146\RISER DESIGN.xls I I I ,I I I I I' I I I I I I I I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 7 DESIL T BASIN DESIGN 7.2 -Riser and Desilt Basin Calculations "Proposed Desilt Basin #3" AH:ad H:IREPORTS123521146IA02.doc W.O.2352·1481170 8121i2006 8:23 AM I I I I I I I I I I, I I I I I I I I I DESIL T BASIN DESIGN LA COSTA GREENS -NEIGHBORHOODS 1.2 AND 1.3. EXISTING DESIL T BASIN #3 -NEIGHBORHOOD 1.3 Per Option 2, Part 8 of Section A of the State Water Resources Control Board Order No. 99-08-DWQ, sediment basins shall, at a minimum, be designed as follows: Sediment basins, as measured from the bottom of the basin to the principle outlet, shall have at least capacity equivalent to 3,600 cubic feet of storage per acre draining into the sediment basin. The length of the basin shall be more than twice the width of the basin. The length is determined by measuring the distance between the inlet and the outlet; and the depth must not be less than three feet nor greater than five feet for safety reasons and for maximum efficiency. GRADED AREA TO BASIN 100-YEAR PEAK FLOW TO BASIN REQUIRED STORAGE CAPACITY BELOW PRINCIPLE OUTLET ELEV. BOTTOM OF BASIN ELEVATION RISER/PRINCIPLE SPILLWAY EL. ------------> c:::II::J acres -----------> ~CfS -------------> ------------> 12456 fe 461 CY 0.29 acre-ft. ~feet ~feet DEPTH BELOW PRINCIPLE OUTLET 3.0 Ifeet IDESIGN BASIN BOTTOM WIDTH 1------------> 63t3 feet DESIGN BASIN BOTTOM LENGTH 111 feet DESIGN STORAGE CAPACITY 21411 ft3 BELOW PRINCIPLE OUTLET ELEV. 793 CY 0.49 acre-ft. 11 OO-YEAR HW OVER RISER 1-------------> ~feet 100-YEARWSE OVER RISER 306.0 feet FREEBOARD ABOVE 1.1 1ft• 100-YEAR WSE ITOP OF BASIN ELEVATION 1------------> . 307.1 Ifeet (From AES-99 Output and Hydro Map) (From AES-99 Output and Hydro Map) (From Grading Plans) (From Grading Plans) (3 <= Depth <= 5 feet) (Length> 2 * Width) (From Riser Design Spreadsheet) (From Grading Plans) * Emergency spillway crest elevation shall be set at or above 100-Year WSE. The emergency spillway shall be sized to convey the 100-year runoff assuming 100% clogging of principle spillway. FOR BROAD-CRESTED EMERGENCY SPILLWAY WEIRS: If the CREST ELEVATION = -------------> Then the Spillway Opening Must Be = 8/11/2006 ~feet r:::IE:Jfeet 6of7 H:\EXCEL\2352\146\DESIL T BASIN-OPTION 2.xls I I I I I I I, I I I I I I I I I I· II I RISER DESIGN FOR DESIL T BASIN LA COSTA GREENS -NEIGHBORHOODS 1.2 AND 1.3 Existing Desilt Basin #3 -Neighborhood 1.~ Weir Formula for Orifices & Short Tubes (free & submerged): Q = 0.85*CA(2gH)1/2 Q = 0.85*0.6A(64.32H) 1/2 Q = 4.1A(H)1/2 Therefore, H = (Q/4.1A) 2 (Equation 1) Weir Formula for riser acting as straight weir: Q = CLH2I3 Therefore, H = (Q/3.3L) 213 (Equation 2) Node 203 : where: 0.85 is a reduction factor for trash rack (cgrresponding to a 1'5% reduction for the gr~te) C = Orifice Coefficient where: = 0.6 from Table 4-10, Kings. Handbook A = Cross-Sectional Area of Orifice (ff) 9 = Gravitational Constant = 32.16 ftls2 H = Head above Top of Riser (ft) C = Weir Coefficinet = 3.3 from Eqn. 5-40, Kings Handbook L = Length of Weir (ft) H = Head above Top of Riser (ft) Q100 = 4.35 cfs Riser d = 36 in Thus, A = 7.069 sq. ft. ---+,. H = 0.02 ft. (Eqn.1) (Eqn.2) L = 9.425 ft. ,. H = 0.27 ft. Therefore: I H = 0.27 ft. I 8111/2006 7of7 H:\EXCEL\2352\146\RISER DESIGN.xls I I I, I- I I I, I I: I I 1_-, -, I- I: - I I I i ' I -VIlli I I "I" I I I I I I I I, I I I I I ,I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTERS RIP RAP DESIGN AH:ad H:\REPORTS\2~52\146IA02.doc W.O.2352-1461170 8121/2006 8:23 AM , I I I I I: I I; I I I I, I I I I I ; ~. 'I I 'I RIPRAP SIZING LA COSTA GREENS -NEIGHBORHOOD 1.2 1.3 DEVELOPER IMPROVEMENTS Grassy Swale (Refer to Developed Condition Hydrology Map in Chapter 10) Ditch Diameter, D = 4.0 ft Velocity, v = 0.56 fps (From FlowMaster Output) Use 0-40: Type 1 Rock Class: No.3 Backing (Per SDRSD D-40 and 2003 Regional Supplement to "Greenbook 2003" 'Standard Specifications) Length, L= 16.0 ft Upstream Width, W= 8.0 ft Downstream Width, W= 12.0 ft Using 3:1 side slopes and placing riprap up to the top of pipe: Total Upstream W = 20.0 ft Total Downstream W= 24.0 ft (Per SDRSD D-40) Thickness, T = 0.6 ft (Per SDRSD 0-40 and 2003 Regional Supplement to "Green book 2003" Standard Specifications) Filter Blanket: Upper Layer: 3/16. II Crushed Rock (or equivalent) Thickness, T = 0.6 ft Lower Layer: Not Required (Per 2003 Regional Supplement to "Greenbook 2003" Standard Specificatiom H:\EXCEL\2352\146\RIPRAP.xlsGrassy Swale -Rip Rap 8/21/2006 'I I I I I,' I I ,I I I I I I I I II I 'I I I RIPRAP SIZING 0-40 ENERGY DISSIPATOR DIMENSIONS For z = 3, depth = 0: Per San Diego Regional Standard Drawing (Dwg. No. D-40): D (in) d (ft) W 1 (ft) W (ft) L (ft) TW1 12 0.50 4.0 4.0 10.0 7.0 18 0.75 4.0 4.5 10.0 8.5 24 1.00' 4.0 6.0 10.0 10.0 30 1.25 5.0 7.5 10.0 12.5 36 1.50 6.0 9.0 12.0 15.0 42 1.75 7.0 10.5 14.0 17.5 48 2.00 8.0 12.0 16.0 20.0 54 2.25 9.0 13.5 18.0 22.5 60 2.50 10.0 15.0 20.0 25.0 66 2.75 11.0 16.5 22.0 27.5 72 3.00 12.0 18.0 24.0 30.0 78 3.25 13.0 19.5 26.0 32.5 84 3.50 14.0 21.0 28.0 35.0 90 3.75 15.0 22.5 30.0 37.5 H:\EXCEL\2352\146\RIPRAP.xlsD-40 W 1=2*D (min) D FLOW o o o o o TW 7.0 9.0' 12.0 15.0 18.0 21.0 24.0 27.0 30.0 33.0 36.0 39.0 42.0 . 45.0 8/21/2006 I ,I ,I I I I I ) I I I I -I 'I-- I- I-I I I I I~-__ ~~--- IX I I I I I I I I I I I I' I I I I I I :1 I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 9 APPENDICES' Appendix 9.1 . Hydrologic Analysis Excerpts from."Mass- Graded Hydrology Study for La. Costa Greens Neighborhoods 1.1-1.3 & EI Camino Real' . Widening" AH:ad H:\REPORTSI2352\146\A02.doc W.O.2352·1461170 812112006 8:23 AM I '1 I I I I I I I I I I I I I I I I 'I MASS-GRADED HYDROLOGY STUDY' for LA COSTA GREENS NEIGHBORHOODS 1.1-1.3" & EL CAMINO REAL WIDENING City of Carlsbad, California Prepared for: . Real Estate Collateral Management Company c/o Morrow Development 1903 Wright Place Suite 180 Carlsbad, CA 92008 W.O. 2352-138 August 23, 2005 Hunsaker & Associates San Diego, Inc. Raymond L. Martin, R.C.E. Vice President AH:ad H:IREPORTSI2352113B Greens 1.1 thru 1.3131d SUBMITTi\L\A03.doc W.O.2352·13B 81111200612:30 PM I I I I I I I I I I I' I I I I I I I il Mass-Graded Hydrology Study La Costa Greens Neighborhoods 1.1-1.3 & EI Camino Real Widening CHAPTER 3 RATIONAL METHOD HYDROLOGIC ANALYSIS . . (AES MODEL OUTPUT) 3.2 -100-Year Mass-Graded Condition 'AES Model Output. AH:ad H:IREPORTSI23521138 Greens 1.1 thru 1.3\3nl SU~MIITALIA03.doc W.O.2352-138 81111200612:33 PM I I I I I I I I I I I I I I I 1 I I' ----------------------------------------------------------------------~----- »»>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< ================================================================~=========== 100 YEAR RAINFALL INTENSITY (INCH/HOUR) = 4.203 *USER SPECIFIED (SUBAREA) : INDUSTRIAL DEVELOPMENT RUNOFF COEFFICIENT = .9000 SUBAREA AREA(ACRES) 0.67 SUBAREA RUNOFF (CFS) = 2.53 TOTAL AREA(ACRES) 0.83 TOTAL RUNOFF(CFS) = 3.45 TC(MIN) = 11:96 **************************************************************************** FLOW PROCESS FROM NODE 117.00 TO NODE 117.00 IS CODE = 1 »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< ============================================================================ TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 1 ARE: TIME OF CONCENTRATION(MIN.) =' 11.96 RAINFALL INTENSITY (INCH/HR) = 4.20 TOTAL STREAM AREA(ACRES) = 0.83 PEAK FLOW RATE (CFS) AT CONFLUENCE = 3.45 **************************************************************************** FLOW PROCESS FROM NODE 118.00 TO NODE 117.00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< ============================================================================ *USER SPECIFIED (SUBAREA) : INDUSTRIAL DEVELOPMENT RUNOFF COEFFICIENT = .8900 INITIAL SUBAREA FLOW-LENGTH = 225.00 UPSTREAM ELEVATION = 315.00 DOWNSTREAM ELEVATION = 309.80 ELEVATION DIFFERENCE = 5.20 URBAN SUBAREA OVERLAND TIME OF FLOW (MINUTES) 4 .289 TIME OF CONCENTRATION ASSUMED AS 6-MlNUTES 100 YEAR RAINFALL INTENSITY (INCH/HOUR) = 6.559 SUBAREA RUNOFF (CFS) 4.09 TOTAL AREA(ACRES) = 0.70 TOTAL RUNOFF (CFS) '4.09 **************************************************************************** FLOW PROCESS FROM NODE 117.00 TO NODE 117.00 IS CODE'= 1 ---------------------------------------------------------------------------~~ »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< »»>AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES««< ============================================================================ TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 2 ARE: TIME OF CONCENTRATION (MIN. ) 6 . 00 RAINFALL INTENSITY(INCH/HR) = 6.56 TOTAL STREAM AREA(ACRES) = 0.70 PEAK FLOW RATE(CFS) AT CONFLUENCE = 4.09 ** CONFLUENCE DATA ** STREAM RUNOFF Tc INTENSITY AREA I I I I I I I I I I I I I i NUMBER· (CFS) (MIN. ) ( INCH/HOUR) (ACRE) 1 3.45 11.96 4.203 0.83 2 4.09 6.00 6.559 . 0.70 RAINFALL INTENSITY AND TIME OF CONCENTRATION RATIO CONFLUENCE FORMULA USED FOR 2 STREAMS. **' PEAK FLOW RATE TABLE ** STREAM RUNOFF Tc IN:r'ENSITY NUMBER (CFS) (MIN. ) (INCH/HOUR) 1 6.30 6.00 6.559 2 6.07 11.96 4.203 COMPUTED CONFLUENCE ') (! No.OE.. ..iZ.O PEAK FLOW RATE (CFS) 6.00 TOTAL AREA (ACRES) = l.53 **********************************************************************.****** FLOW PROCESS FROM NODE 117.00 TO NODE· 120.00 IS CODE = »»>COMPUTE PIPEFLOW TRAvELTIME THRU SUBAREA««< »»>USING USER-SPECIFIED PIPESIZE««< 4 ============================================================================ DE~TH OF FLOW IN 18.0 INCH PIPE IS 4.1 INCHES PIPEFLOW VELOCITY (FEET/SEC.) = 20.5 UPS~REAM NODE ELEVATION = 302.36 DOWNSTREAM NODE ELEVATION = 278.47 FLOWLENGTH (FEET) = 80 . 68 MANNING'S N = O. 01·3 GIVEN PIPE DIAMETER(INCH) = 18.00 NUMBER OF PIPES 1 PIPEFLOW THRU SUBAREA(CFS) 6.30 . TRAVEL TIME (MIN.) = 0.07 TC (MIN.) = 6.07 .J <!. NOO~ i~o **************************************************************************** FLOW PROCESS FR9M NODE 120.00 TO NODE '114.00 IS CODE = 52 »»>COMPUTE NATURAL VALLEY CHANNEL FLOW««< »»>TRAVELTIME THRU SUBAREA««< ============================================================================ UPSTREAM NODE ELEVATION = 277.50 DOWNSTREAM NODE ELEVATION = 125.00 CHANNEL LENGTH THRU SUBAREA(FEET) 1578.00 .CHANNEL SLOPE = 0.0966 CHANNEL FLOW THRU SUBAREA (CFS) = 6.30 FLOW VELOCITY (FEET/SEC) = 6.93 (.PER PLATE D-6.1) TRAVEL TIME(MIN.) = 3.80 TC(MIN.) = 9.86 **************************************************************************** FLOW PROCESS FROM NODE 120.00 TO NODE 114.00 IS CODE = 8 »»>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< . . ============================================================================ 100 YEAR RAINFALL INTENSITY (INCH/HOUR) = 4.760 *USER SPECIFIED (SUBAREA) : RURAL DEVELOPMENT RUNOFF COEFFICIENT = .4500 I I I I I I I I I I I" INDUSTRIAL DEVELOPMENT RUNOFF COEFFICIENT "INITIAL SUBAREA FLOW-LENGTH = 376.00 UPSTREAM ELEVATION = DOWNSTREAM ELEVATION = 324.30 317.15 ELEVATION DIFFERENCE = 7 . 15" .8700 URBAN SUBAREA OVERLAND TIME OF FLOW (MINUTES) 6 .480 100 YEAR RAINFALL INTENSITY (INCH/HOUR) = 6.241 SUBAREA RUNOFF (CFS) 4.18 TOTAL AREA(ACRES) = 0.77 TOTAL RUNOFF (CFS) 4.18 *******************************************************~******************** FLOW PROCESS FROM NODE 202.00 TO NODE 203.00 IS CODE = 51 »»>COMPUTE TRAPEZOIDAL CHANNEL FLOW««< »»>TRAVELTIME THRU SUBAREA««< ============================================================================ UPSTREAM NODE ELEVATION = 317.15 DOWNSTREAM NODE ELEVATION = 307.10 CHANNEL LENGTH THRU SUBAREA(FEET) = 625.40 CHANNEL SLOPE = 0.0161 CHANNEL BASE (FEET) = 0.00 "Z" FACTOR:= 99.990" MANNING'S FACTOR = 0.030 MAXIMUM DEPTH(FEET) = 0.50 CHANNEL FLOW THRU SUBAREA(CFS) = 4.18 FLOW vELOCITY(FEET/SEC) = 1.29 FLOW DEPTH(FEETl 0.18 TRAVEL TIME(MIN.) = 8.10 TC(MIN.) = 14.58 **************************************************************************** FLOW PROCESS FROM NODE 202.00 TO NODE 203.00 IS CODE = 8 »»>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< ====================================================~======================= 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 3.699 *USER SPECIFIED (SUBAREA) : INDUSTRIAL DEVELOPMENT RUNOFF COEFFICIENT = .8700 4.9 SUBAREA RUNOFF CFS 15.90 L",T=O,...,T."..,AL=ARE,--_A_(:..".A-:-C_RE=-S=-,)~ ___ 5 _. 7_1~_T_O_TAL __ R_UN_O_F_F~( C_F_S....;l_= ___ --' (J NoD E. £.0"l- TC(MIN) = 14.58 **************************************************************************** FLOW PROCESS FROM NODE 203.00 TO NODE 204.00 IS CODE = »»>COMPUTE PIPEFLOW TRAVELTIME THRU SUBAREA««< »»>USING USER-SPECIFIED PIPESIZE««< 4 ====================================================~======================= DEPTH OF FLOW IN 24.0 INCH PIPE IS 6.9 INCHES PIPEFLOW VELOCITY(FEET/SEC.) = 26.9 UPSTREAM NODE ELEVATION = 298.96 DOWNSTREAM NODE ELEVATION = FLOWLENGTH(FEET) = 47.06 GIVEN PIPE DIAMETER(INCH) = PIPEFLOW THRU SUBAREA (CFS) TRAVEL TIME (MIN.) = 0.03 286.20 MANNING'S N = 0.013 24.00 NUMBER OF PIPES = 1 20.08 .... 1 T_C_(_M_IN_._) __ 14_._6_1 .... 1 e NODE. 2.0 t I ,I ,I 1 I I I 1 I I I I I I I I , l FLOW PROCESS FROM NODE 124.00 TO NODE 100.00 IS CODE = 8 ---------------------------------------------------------~------------------ »>~>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< ============================================================================ 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 3.038 *USER SPECIFIED (SUBAREA) : RURAL DEVELOPMENT RUNOFF COEFFICIENT = .4500 SUBAREA AREA(ACRES) 16.38 SUBAREA RUNOFF (CFS) '22.39 TOTAL AREA(ACRES) 20.22 TOTAL RUNOFF(CFS) = 29.33 TC(MIN) 19.78 **************************************************************************** FLOW PROCESS FROM NODE 100.00 TO NODE 100.00 IS CODE = »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< »»>AND COMPUTE VARIOUS CONFLUENCED STREAM, VALUES««< 1 ============================================================================ , TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 2 ARE: TIME OF CONCENTRATION(MIN.) = 19.78 RAINFALL INTENSITY (INCHj:EIR) = 3.04' TOTAL STREAM AREA (ACRES) = 20 . 22 PEAK FLOW RATE (CFS) AT CONFLUENCE = 29.33 ** CONFLUENCE DATA ** STREAM RUNOFF Tc INTENSITY NUMBER (CFS) (MIN. ) ( INCH/HOUR) 1 116.28 22.50 2.796 2 29.33 19.78 3.038 AREA (ACRE) 70.87 20.22 RAINFALL INTENSITY AND TIME OF CONCENTRATION RATIO' CONFLUENCE FORMULA USED FOR 2 STREAMS. ** PEAK FLOW RATE TABLE ** STREAM RUNOFF Tc INTENSITY NUMBER (CFS) (MIN.) (INCH/HOUR) 1 136.36 19.78 3.038 2 143.28 22.50 2.796 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE (CFS) 143.28 Tc(MIN.) = TOTAL AREA (ACRES) = 91.09 e. NoDE. '100! 22.50' -t::/<IS-r~N9 ,.D-O+ ~ +--------------------------------------------------------------------------+ I END BASIN #1 -EL CAMINO REAL WIDENING, LA COSTA GREENS NEIGHBORHOOD I I 1.1 THROUGH 1.3, AND LA COSTA GREENS RV STORAGE AR&A (NODE SERIES 100) I I BEGIN BASIN #2 -LA COSTA GREENS SOUTH LOT (NODE SERIES 200) I +-------~------------------------------------------------------------~-----+, **************************************************************************** FLOW PROCESS FROM NODE 201. 00 TO NODE 202~00 IS CODE = 21 »»>RATIONAL METHOD INITIAL SUBAREA ANALYSIS««< ============================================================================ *USER SPECIFIED (SUBAREA) : I I I I I I I. I' I I I I I I I II I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1:2 & 1.3 CHAPTER 9. APPENDICES . Appendix 9.2· H'ydrologic Analysis Excerpts from "Drainage' Study for A/ieante Road -North of Poinsettia" AH:ad H:IREPORTS\23521146\A02.doc W.O 2352-1461170 8/21/2006 8:23 AM I I I I I I I I I I I I I I I I I I I DRAINAGE STUDY for ALICANTE ROAD NORTH OF POINSETTIA LANE. City of Carlsbad, California Prepared for Real Estate Collateral·Management Company c/o Morrow Development 1903 Wright Place Suite 180 Carlsbad, CA 92008 W.O. 2352-81 December 1, 2003 Hunsaker & Associates San Diego, Inc. Raymond L. Martin, R.C.E. Project Manager AH h:lrepot1S1235210B113rd submittal\a02.doc W.O.2352·81 11/26/20031:41 PM . I I I I I I I I I I I I I I I **************************************************************************** FLOW PROCESS FROM NODE 425.00 TO NODE 426.00 IS CODE = 8 »»>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< ============================================================================ 100 YEAR RAINFALL INTENSITY (INCH/HOUR) = 3.932 *USER SPECIFIED (SUBAREA) : RURAL DEVELOPMENT RUNOFF COEFFICIENT = .3500 SUBAREA AREA(ACRES) 20.00 SUBAREA RUNOFF (CFS) TOTAL AREA(ACRES) 22.00 TOTAL RUNOFF(CFS) = TC(MIN) = 13.26 27.53 30.57 ************************************~*************************************** FLOW PROCESS FROM NODE 426.00 TO NODE 427.00 IS CODE =' 52 »»>COMPUTE NATURAL VALLEY CHANNEL FLOW««< »»>TRAVELTIME THRU SUBAREA««< ===============================================~============================ UPSTREAM NODE ELEVATION = 175.00 DOWNSTREAM NODE ELEVATION = 105.00 CHANNEL LENGTH THRU SUBAREA (FEET) = 1400.00 CHANNEL SLOPE = 0.0500 CHANNEL FLOW THRU SUBAREA(CFS) = 30.57 FLOW VELOCITY(FEET/SEC) = 7.53 (PER PLATE D-6.1) TRAVEL TIME(MIN.) = 3.10 TC(MIN.) = 16.36 **************************************************************************** FLOW PROCESS FROM NODE 426.00 TO NODE 427.00 IS CODE = 8 »»>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< ============================================================================ 100 YEAR RAINFALL INTENSITY (INCH/HOUR) = 3.434 *USER SPECIFIED (SUBAREA) : COMMERCIAL DEVELOPMENT RUNOFF SUBAREA AREA (ACRES) 30 . 00 TOTAL AREA(ACRES) = 52.00 TC(MIN) = 16.36 COEFFICIENT = .6000 SUBAREA RUNOFF (CFS) = TOTAL RUNOFF (CFS) =' 61.81 92.38 *********************************************************************~****** FLOW PROCESS FROM NODE 427.00 TO NODE 427.00 IS CODE = '8 »»>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW««< ============================================================================ 100 YEAR RAINFALL INTENSITY (INCH/HOUR) = 3.434 *USER SPECIFIED (SUBAREA) : SINGLE FAMILY DEVELOPMENT RUNOFF COEFFICIENT = .5000 = 36.00 SUBAREA RUNOFF CFS 61.81 ,-::T:-:O:-:T;.:.AL=,:;.:AREA:;.:::;:;~(A::.:C::.:R..:::E~S,..:.) ___ .:...8 8.:..-. O.:...O.:..---.,;T.:...O..;.;T;;.;AL~.:...RUN..;;.;;.;,.O.:...F.:...F;...:...( C.:...F.:...S~)_=_.;.;;..;....;;.... ___ .... Co NOD 1::. 4-2:9- TC (MIN) = 16. 36 ~'1,.I=='TIN9,?-"'34- . H~w7'n.l..-+---------------------------------,----------------------------------~------+ I CODE 8 FRON NODE 427 TO NODE 427 CORRESPONDS TO "SUBAREA-CODE 8" AS I I SHOWN ON THE ULTIMATE CONDITION HYDROLOGY MAP LOCATED IN CHAPTER 7. I I I \ 1 1 1 1 1 1 1 I I I .1 1 I I I +--------------------------------------------------------------------------+ **************************************************************************** FLOW PROCESS FROM NODE 427.00 ·TO NODE 400.00 IS CODE ;= »»>COMPUTE PIPEFLOW TRAVELTIME THRU SUBAREA««< »»>USING USER-SPECIFIED PIPESIZE««< 4 =========================================~================================== PIPEFLOW VELOCITY{FEET/pEC.) = 12.3 UPSTREAM NODE ELEVATION = 105.00 104.37 MANNING'S N = 0.013 DOWNSTREAM NODE ELEVATION = FLOWLENGTH{FEET)'= 56.19 GIVEN PIPE DIAMETER{INCH) = PIPEFLOW THRU SUBAREA (CFS) TRAVEL TIME{MIN.) = 0.08 48.00 NUMBER OF PIEES 1 154.20 [!...T....;C;....;{.;..M_IN_ . ..;.)_=_1_6-' .. '-4 .... 4-11 Q. NO 05. +2"1-~/<.l ~ T I t-J <=j P -'3+ ;-\-E:1\'pW1(L.L.. +--------------------------------------------------------------------I USE 48" RCP BASED ON INLET CONTROL CALCULATION SHOWN IN CHAPTER 5 I OF THIS REPORT. I +--------------------------------------------------------------------------+ **************************************************************************** FLOW PROCESS FROM NODE 400.00 TO NODE 400.00 IS CODE = »»>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE««< »»>AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES««< 1 ============================================================================ TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 2 ARE: TIME OF CONCENTRATION{MIN.) = 16.44 RAINFALL INTENSITY (INCH/HR) = 3.42 TOTAL STREAM AREA (ACRES) = 88 . 00 PEAK FLOW RATE{CFS) AT CONFLUENCE = 154.20 ** CONFLUENCE DATA ** STREAM NUMBER 1 2 RUNOFF (CFS) . 396.19 154.20 Tc (MIN.) 19.08 16.44 INTENSITY. (INCH/HOUR) 3.110 3.424 AREA (ACRE) 283.67 88.00 RAINFALL INTENSITY AND TIME OF CONCENTRATION RATIO CONFLUENCE FORMULA USED FOR 2 STREAMS. ** PEAK FLOW RATE TABLE ** STREAM RUNOFF NUMBER (CFS) 1 514.05 2 536.24 Tc (MIN. ) 16.44 19.08 INTENSITY ( INCH/HOUR) 3.424 3.110 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE (CFS) 536.24 Tc{MIN.) = 19.08 TOTAL AREA{ACRES) = 371.67 I I I I I I I I I I I I I I I I I I +--------------------------------------------------------------------------+ I I END 100-YEAR HYDROLOGY ANALYSIS FOR ALICANTE ROAD -NORTH (PHASE 1) I I I L +--------------------------------------------------------------------------+ ============================================================================ END OF STUDY SUMMARY: PEAK FLOW RATE (CFS) = 536.24 Tc (MIN.) = 19.08 TOTAL AREA(ACRES) = 371.67 ============================================================================ END OF RATIONAL METHOD ANALYSIS 1 I I.: I ·1 I' I I I I I I I I I I 1 I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 9 APPENDICES Appendix 9.3 Hydraulic Analysis Excerpts from "Drainage Study for A/ieante Road -North of Poinsettia" AH:ad H:IREPORTS123521146\A02.dac W.O.2352·1461170 &2112006 8:23 AM I I I I .1 I I I I I I I I· I l •• i' J • , DRAINAGE STUDY for ALICANTE ROAD NORTH OF POINSETTIA LANE City of Carlsbad, California Prepared for Real Estate Collateral Management Company c/o Morrow Development 1903 Wright Place Suite 180 Carlsbad, CA 92008 W.O. 2352-81 December 1, 2003 Hunsaker & Associates San Diego, Inc. Raymond L. Martin, RC.E. Project Manager AH h:lrepcrts1235210B113rd submlttana02.doc I I I I I I I I I I I I I I I I I Scenario: ALICANTE ROAD -NORTH (PHASE 1) j123 ALICANTE ROAD. NORTH (PHASE 2) // ~P=:ER~D~W=G:-",::,N~0::':=',::4",0c.::O:.::.8c::J=~:-::-_::--______ ~L-___________ ----STA. 86tOO .00 ALICANTE ROAD· NORTH (PHASE 1) PER DWG. NO. 397·2F SHEETll I ~ .. ' G...... 1·133" P'8 HW·402 _ ____ .~ . .() <. /ca.40~' '?? ,,<:> : 1·127 ~ •. J. CO.4 0 3 [3--"" '" )"::: P·13 LUG·40S ~ -El C6.40 6 ! I .... I a:~ l I 0.407; .. l ! SHEETll ;' ~S~H~E~E=T~1=0--------~/~----------------STA.79+00.00 ~ ""'006.410 'I'", ,,'" ... 13'1.411 'I"';" CO·408 SH EET 10 ..... , :::.:.=.:..:..=-________________ :.:.,.-__________ STA. 74+00.00 SHEeT9 \\ ~ Title: ALiCANTE ROAD h:\.,. \2352\81 \3rd submittal delta 3\final.stm 11/26/03 01 :33:50 PM © Haestad Methods, Inc. >,\'0 '~ ..... " PO IN SETTIA LANE PER D WG. 397·21 1·420 Hunsaker & Associates· San Diego, Inc. 37 Brookside Road Waterbury, CT 06708 USA Project Engineer: H&A Employee StormCAD v5.5 [5.5003] +1-203-755-1666 Page 1 of 1 .-.----.-:-- --.--- - I Label U/S DIS U/S DIS Node Node Ground Ground Elevation Elevation (ft) (ft) P-7 CO-123 CO-404 160.80 153.00 P-8 1-127 CO-404 153.00 153.00 P-9 1-133 CO-404 153.00 153.00 P-10 CO-404 CO-403 153.00 152.00 P-11 HW-402 CO-403 141.60 152.00 P-12 CO-403 LUG-40! 152.00 147.65 P-13 CB-406 LUG-4O! 145.70 147.65 P-14 LUG-40E 0-407 147.65 134.88 P-15 0-407 CO-408 134.88 124.27 P-16 CB-410 1-411 122.80 124.48 P-17 1-411 CO-408 124.48 124.27 P-18 1-416 CO-408 124.48 124.27 P-19 CO-408 CO-417 124.27 118.39 P-20 CO-417 CO-418 118.39 114.67 P-21 1-420 CO-418 114.82 114.67 P-22 1-422 CO-418 114.82 114.67 P-23 CO-418 CO-400, 114.67 116.50 P-24 HW-427 CO-400 109.00 116.50 Title: ALiCANTE ROAD h:\ ... \2352\81\3rd submittal delta 3\final.stm 11/26/03 01 :34:24 PM Scenario: ALiCANTE ROAD -NORTH (PHASE 1) Combined Pipe\Node Report UlS DIS Length Pipe Section Mannings System Max HGL Invert Invert (ft) Slope Size unll Flow Capacity In Elevation Elevation (%) (efs) (cfs) (ft) (ft) (ft) 150.82 137.15 :WO.30 4.71 36 inch. 0.013 92.71 144.73 153.68 141.56 138.15 27.24 12.52 24 inch 0.013 5.15 80.04 142.61 138.75 138.65 5.26 1.90 18 inch 0.013 4.75 14.48 142.71 136.65 134.78 27.67 6.76 42 Inch 0.013 97.70 261.54 141.10 134.00 133.67 66.33 0.50 72 inch 0.013 291.89 298.70 141.15 133.34 131.21 85.67 2.49 72 inch 0.013 377.51 667.75 138.56 134.96 133.21 47.03 3.72 24 inch 0.013 6.15 43.64 136.46 131.21 122.27 360.29 2.48 72 Inch 0.013 382.31 667.08 136.46 121.27 113.44 360.25 2.17 84 inch 0.013 382.31 941.76 126.42 115.33 114.93 9.75 4.10 18 inch 0.013 7.87 21.28 121.47 114.60 113.44 ~9.25 3.97 18 inch 0.013 10.39 20.92 121.15 113.56 113.44 3.25 3.69 18 Inch 0.013 3.91 20.18 120.87 113.11 108.37 268.18 1.77 84ineh 0.013 392.76 849.26 118.33 108.04 103.82 236.93 1.78 84 inch 0.013 392.76 852.53 113.26 104.63 103.57 35.25 3.01 18 inch 0.013 3.44 18.21 110.81 103.85 103.57 9.25 3.03 18 inch 0.013 3.36 18.27 110.78 103.49 102.20 65.33 1.97 84 Inch 0.013 396.19 897.64 108.74 105.00 104.37 56.19 1.12 48 inch 0.013 154.20 152.09 108.63 Hunsaker & Associates -.San Diego, Inc. © Haestad Methods, Inc. 37 Brookside Road" Waterbury, CT 06708 USA +1-203-755-1666 - --- HGL Velocity Velocity Out (ft) 142.70 142.70 142.70 140.83 140.83 136.46 136.46 127.66 120.86 121.42 120.86 120.86 114.53 110.77 110.77 110.77 107.88 107.79 In Out (tus) (tus) 13.34 13.12 3.10 1.64 2.69 2.69 10.15 10.15 10.32 10.32 ! 14.45 14.39 2.43 1.96 14.58 14.29 12.59 9.93 4.45 4A5 5.88 5.88 2.21 2.21 12.75 10.95 12.75 10.21 1.95 1.95 1.90 1.90 12.81 11.84 12.87 13.47 Project Engineer: H&A Employee StormCAD v5.5 [5.5003] Page 1 of 1 - ._._._._,_:_.-- -_.:-- - - -----Profile Scenario: ALiCANTE ROAD -NORTH (PHASE 1) ALICANTE ROAD -NORTH (PHASE 1 ) MAIN LINE (NODES 123-403) -Label: CO-1 Rim: 160.8 Sump: 150.812 ft Label: CO-404 Rim: 153.00 ft Sump: 136.65 165.00 . III ~.... I 160.00 ~ ..... ft 155.00 150.00 Elevation (ft) Label: P-7 _.' Invert: 150.82 ft Dnt Invert: 137.15 ft L: 290.30 ft Size: 36 inch 0+00 1+00 Title: ALiCANTE ROAD --.......... I-H-I-I 1145.00 1--1;1 I 140.00 136.65 ft 134.78 ft L: 27.67 ft 42 inch 6.76 % 2+00 Station (ft) 3+00 Hunsaker & Associates -San Diego, Inc. I-~----tl 135.00 130.00 4+00 h:\ ... \2352\81\3rd submittal delta 3\final.stm 11/26/03 01 :34:44 PM © Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA +1-203-755-1666 Project Engineer: H&A Employee StormCAD v5.5 [5.5003] Page 1 of 1 I I I I I I I I I I I I I I I I I I I Profile Scenario: ALiCANTE ROAD -NORTH (PHASE 1) ALICANTE ROAD -NORTH. (PHASE 1) LATERAL (NODES 127-133) Label: 1-127 - Rim: 153.00 ft Sump: 141.56 ft Label: P-8- Up. Invert: 141.56 ft On. Invert: 138.15 ft L: 27.24 ft Size: 24 inch S: 12.52 % 0+00 Title: ALiCANTE ROAD h:\ ... 12352\81\3rd submittal delta 3\final.stm 11/26/03 01 :35:00 PM © Haestad Methods, Inc. Label: CO-404 Rim: 153.00 ft· Sump: 136.65 ft Label: 1-133 . Rim: 153.00 ft Sump: 138.75 bel: P-9 p. Invert: .138.75 n. Invert: 138.65 5.26 ft : 18 inch . 1.90 0/0 155.00 150.00 Elevation (ft) 145.00 140.00 0+50 Station (ft) 135.00 1+00 Hunsaker & Associates -San Diego, Inc. 37 Brookside Road Waterbury, CT 06708 USA Project Engineer: H&A Employee StormCAD v5.5 [5.5003] +1-203-755-1666 Page 1 of 1 ~---~,...----.... -,--:----1--- Label: HW-402 ~ Rlm:141.60fl '. Sump: 134.00 n Label: P-11 - Up. Invert: 134.00 It On. Invert: 133.67 fI L: 66.33 fI Size: 72 in ch S: 0.50 % Profile Scenario: ALiCANT,E ROAD -NORTH (PHASE 1) .ALlCANTE ROAD -NORTH (PHASE 1 ) MAIN LINE (NODES 402-400) -.-.. --160.00 -,--.--.-, 150.00 ~ I 1""-" "" I I Sump: 1~1.27 n ·-1--·-+----.. ·'1140.00 "-./ ,I -La CO-40B 24.27 II : 113.11 ~'-I---=: _ III I --·1 I: I / +---1130.00 --L: 1---· -=1. / /1 ·1---1120.00 - Elevation (ft) Label: P-12 Up. Inver!: 133.34 fl 1 ---S --_n_n 1 :lLapel' I:'-Jp' --On. Invert: 131.21 fl ---. 2.~-a-o/o 11_ I~ .. ...4. ~.., .. ""'71. P l: 85.67 II Size: 72 In ch S: 2.49 % ~'.:·::I'r:·:lI::·~·:·[;-:-. _. I r .. :.IJ~I--.. I-----ll10.00 ---+·---If----+---II----+---t-------rl TI:::iil~:l' :rIT~~iii·:linl::~!nm'~:u·~!:1 1 ... _ L~ . 1-1----1-·------1100.00 0"'00. 1+00 2"'00 Title: ALICANTE ROAD h:\ ... \2352\B1\3rd submittal delta 3\final.stm 11/26/03 01 :35:19 PM 3"'00 4+00 5+00 6+00 7+00 a ... oo 9+00 10+00 11+00 12+00 Station (tt) Hunsaker & Associates -San Diego, Inc. © Haestad Methods, Inc. 37 Brookside Road Waterbury; CT 0670B USA +1-203-755-1666 13+00 14+00 15+00 90.00 .180.00 16+00 Project Engineer: H&A Employee StormGAD v5.5 [5.5003] Page 1 of 1 - I I I- I I I- I I I I I I I- I I '-I- I I l , Profile Scenario: ALICANTE ROAD -NORTH (PHASE 1) ALICANTE ROAD -NORTH (PHASE 1) LATERAL (NODES 406-405) Label: C8-406 - Rim: 145.70 ft Sump: 134.96 ft Label: P-13 Up. In ve rt: 1 34 . 96ft On. In ve rt: 1 33.21 ft L: 47.03 ft Size: 24 inch S: 3.72 % 150.00 __ -Label: LU -405 Rim: 147.6 ft Sump: 131 21 ft 145.00 140.00 Elevation (ft) 135.00 0+00 0+50 Station (ft) 130.00 1+00 Title: ALiCANTE ROAD h:\ ... \23S2\81 \3rd submittal delta 3\final.stm 11/26/03 01 :3-S:38 PM © Haestad Methods, Inc. Project Engineer: H&A Employee Hunsaker & Associates -San Diego, Inc. StormCAD vS.S [S.5003] 37 Brookside Road Waterbury, CT 09708 USA _+1-203-75S-1666 Page 1 of 1 I I I I I. I. I I· I I I I I· I I l , J , , , Profile Scenario: ALICANTE ROAD -NORTH (PHASE 1) ALICANTE ROAD -NORTH (PHASE 1) LATERAL (NODES 410-416) Label: 1-416 - Rim: 124.48 ft Sump: 113.56 ft Label: P-18 ~/­ Up. Invert: 113.56 ft D n. I nve rt: 11 3.4 4 ft L: 3.25 ft Size: 18 inch S: 3.69 % 0+00 -Labkl: CO-408 Riml 124.27 ft Sump: 113.11 ft 130.00 -label: 1-411 : ~im: 124.48 ft u mp: 114.60 ft \ \ ~. -Label: C8-410 Rim: 122.80 ft Su mp: 115.33 ft 125.00 Elevation (ft) 120.00 ,-Label: P-16 Up. Invert: 115.33 ft On. I n vert: 11 4 .9 3 ft L: 9.75 ft Size: 18 inctil S:4.10% -Labf I: P-·17 . Up. Invert: 114.60 ft On. ~nvert: 113.44 ft L: 29.25 ft Size: 18 inch S: 3 97 % 115.00 0+50 Station (ft) 110.00 1 +00 Title: ALiCANTE ROAD Project Engineer: H&A Employee h:\ ... \23S2\81\3rd submittal delta 3\final.stm Hunsaker & Associates -San Diego, Inc. StormCAD vS.S [S.5003] 11/26/03 01 :3S:51 PM © Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06798 USA +1-203-755-1666 Page 1 of 1 I I I I I. I I I I. I I I I· I I I' ·1 I I I - Profile Scenario: ALICANTE ROAD -NORTH (PHASE 1) ALICANTE ROAD -NORTH (PHASE 1) LATERAL (NODES 420-422) Label: CO-4 8-. Rim: 114.67 ft Sump: 103.49 ft Label: 1-420 - . Rim: 114.82 ft Sump: 104.63 ft Label: P-21 Up. Invert: 104.63 ft On. Invert: 103.57 ft L: 35.25 ft Size: 18 inch S: 3.01 0/0 0+00 120 .. 00 -Label: 1-4 2 Rim: 114. 2 ft Sump: 10 .85 ft 115.00 Elevation (ft) 110.00 105.00 Label: P-22 Up. Invert: 03.85-ft On. Invert: 03.57 ft L: 9.25 ft Size: 18 in S: 3.03 % 0+50 Station (ft) 100.00 1+00 Title: ALiCANTE ROAD Project Engineer: H&A Employee h:\ ... \2352\81\3rd submittal delta 3\final.stm Hunsaker & Associates· San Diego, Inc. StormCAD v5.5. [5.5003] 11/26/03 01 :36:03 PM © Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA +1-203-755-1666 Page 1 of 1 I I I I I I I I I I I I I I I I I I I , Label: HW-427- Rim: 109.00 ft Sump: 105.00 ft Title: ALiCANTE ROAD Profile Scenario: ALICANTE ROAD -NORTH (PHASE 1) ALICANTE ROAD -NORTH (PHASE 1) LATERAL (NODES 427-400), ,---------;---------; 120.00 -Label: Rim: 11 .50 ft Sump:' 01.87 ft 1--______ +-+-1-____ ---1 115.00 Elevation, (ft) f---,...-------+-t+------1 110.00 0+00 0+50 Station (ft) 105.00 -Label: p- Up. Invert: 105.00 ft On. Invert: 104.37 ft L: 56.19 ft Size: 48 in h S: 1.12 % 100.00 1 +00 h:I ... \2352\8113rd submittal delta 3\final.stm 11/26/03 01 :36:37 PM © Haestad Methods, Inc. Hunsaker & Associates· San Diego, Inc. 37 Brookside Road Waterbury" CT !;l6'(.OIl USA Project Engineer: H&A Employee StormCAD v5.5 [5.5003] +1-203-755-1666 Page 1 of 1 I I I I I I I I I I I I I I I i. I l I l • HEADWATER DEPTH CALCULATION ALICANTE ROAD NORTH -PHASE 1 (CONST.RUCTION CHAN.GES) 11/26/2003 Given: r~~~ 15.11 N9 ])-34 HW Location:~ Diameter: D = 48-in (From StormCAD output) Discharge: Q = 154.20 cfs (From AES .output) Freeboard: f = 2.00 ft (Minimum requirement) Per Hydraulic Design of Highway Culverts: Appendix 0 -Design Charts, Tables, and Forms Chart 1 -Headwater Depth for Concrete Pipe Culverts with Inlet Control HW/D= HW= HW= 2.20 105.6 in 8.80 ft Ground Surface Elevation = U/S Culvert Invert (Entrance) = HW Elevation (w/o freeboard) = Actual freeboard: f = 1.95 ft 115.75ft 105.00 ft 113.80 ft (From storm drain profiles) (From sto[m drain profiles) HW Elev = 113.80 ft s Ground Surface Elav =' 115.75ft H:\EXCEL\2352\81\3rd.SUBMITTAL\HW Depth Calc 48-inch.xls I I I~" . \ .. I I I I I I I ('" . ·1 .. ·· I I I I 'I I , ... I c. en WJ :J: 0 Z Z .... e l-e:: IIJ :> ..J ::l 0 LL. 0 a: WJ I- LIJ ::E ~ Q ~ cO :r II t:l ISO IS! :H 33 30 21 2.>4 21 13 1~ 12 II 10,000 a,ooo EXAMPLE· 0 .. 04:Z Inc~ (3.3 , ... tl Q-I2.0 eta ¥'" 11 'a fwI (I) %.;! I.~ ~l t.1 7.4 (3) t.: 7.1 ·0 I. 1M 1-1; .=. J...~O H; SCALE (I) (2} (~l ENTRANCE TYPE S .. un ",. willi ~IQ" •• II ~"". ell" .. in 11.411 ... 11 ~r"lt '1I~ ,'·I .. tl"t r ...... 01101 1'Z1 Ir (3) ,n\.c1 ~erlz •• teIl1 Ie Ic .. I. Ill. '"U .... t,r.I'II_t lull", .. 111'4 111"11111 _ a 1,,4 ~ luln." in,,.e ... ill ~.1r IU". CHART 10 ( I ) (3) IS. 5. 4. 3. I.~ .9 .21 --I---I==-.7--l-=-.-r .~ H£AOWATEfI SCALES 2.!:3 REVISal) MAY 19E4 HEADWATER DEPTH FOR CONCRETE PIPE CULVERTS WITH INLET CONTROL 181 I I I I I I I I I I· I· I I· I I '1 I I' I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 9 APPENDICES Appendix 9.4 Revised Hydraulic Analysis for Storm Drai.n and Revised Headwater Depth Calculation for Existing D-34 Headwall (per Drawing No. 397-2F) AH:ad H:IREPORTSI235211461A02.doc W.O.2352·146/170 812112006 8:23 AM I I, I· I I. I I I I I, I I I I l . , 'I l I Scenario: ALiCANTE ROAD NORTH' ___ REVISED IiYDRAWCANlJ.YSIS FOR EXlST1NGSlORM ORAlNM.ONGAUCANTEROAO NORTH(OWG. NO.397·2F) CQ.1Zl /fiJ // AUCOOEROAO.t10RTH(PHASE~ / ~Pffi~OW~G~~~.~~ ________________________ ~ __________________________ SfA~fOO.oo AUCANTEROAO.NORTH(PHASE1) ",I PEROWG NO.397·2F SHffill I I SHffill SHffil0 SHffil0 SIiEET9 Title: ALICANTE ROAD h:\stormcad\2352\ 141 \dwg 397 -2f.stm CO-4OO """ .: C04J7 / , I I I ~ 1-416 04/12106 03:21:08 PM © Haestad Methods, Inc. t~ I I . ~.~ { Poll CW;; ~,~ ClJ.410 J.411 .0 ") \ C0-417 POiNSETIlAWlE PERDWG.397·lH Sf A. 79.0000 Sf A 74fOO.oo J.431 Hunsaker & Associates San Diego, Inc 37 Brookside Road Waterbury, CT 06708 USA SfA.7tlf45.OS AUCANTE DETENTION BASIN Project Engineer: H~ Employee StormCAD v5.5 [5.5005] +1~203-755':1666 Page 1 of 1 ~ ~I'_' ---. ~~ ~_ '_ ._._._._ :~_ --- Label UIS DIS UIS Node Node Ground Elevation P-7 CO-123 CO-404 P-8 1-127 CO-404 P-9 1-133 CO-404 P-10 CO-404 CO-403 P-11 HW-402 CO-403 P-12 CO-403 LUG-405 P-13 CB-406 LUG-405 P-14 LUG-405 CO-407 P-15 CO-407 CO-408 P-16 CB-410 1-411 P-17 1-411 CO-408 P-18 1-416 CO-408 P-19 CO-408 CO-417 P-20 CO-417 CO-418 P-21 1-420 CO-418 P-22 1-422 CO-418 P-23 CO-418 CO P-24 HW-427 CO P-25 CO JS P-26 JS OUTLET Title: ALiCANTE ROAD h:\stormcad\2352\ 141 \dwg 397 -2f.stm 05/15/06 02:59:42 PM (tt) 156.50 153.08 153.00 153.31 139.00 152.15 144.70 148.00 134.88 122.80 124.48 124.48 124.27 118.39 114.82 114.82 114.67 110.00 115.07 116.00 Scenario: ALiCANTE ROAD NORTH Combined Pipe\Node Report DIS U/S DIS Length Slope Pipe Manning's Flow Max Ground Invert Invert (tt) (%) Diameter "n" (cfs) CapC!city Elevation Elevation Elevation D (cfs) (tt) (tt) (tt) 153.31 143.74 137.16 140.50 4.68 36 inch 0.013 92.71 144.32 153.31 141.56 138.15 27.24 12.52 24 inch 0.013 5.15 80.04 153.31 138.75 138.65 5.26 1.90 18 inch 0.013 4.75 14.48 152.15 137.50 136.36 27.67 4.12 42 inch 0.013 97.70 204.20 152.15 134.00 132.76 66.33 1.87 84 inch 0.013 291.89 873.41 148.00 132.43 1;30.08 85.67 2.74 84 inch 0.013 377.51 1,057.09 148.00 134.96 131.10 47.03 8.21 24 inch 0.013 6.15 64.81 134.88 130.08 120.14 360.30 2.76 84 inch 0.013 382.31 1,061.23 124.27 119.81 112.60 360.25 2.00 84 inch 0.013 382.31 903.71 124.48 114.49 114.09 9.75 4.10 18 inch 0.013 7.87 21.28 124.27 113.76 112.60 29.25 3.97 18 inch 0.013 10.39 20.92 124.27 112.72 112.60 3.25 3.69 18 inch 0.013 3.91 20.18 118.39 112.27 106.91 268.18 2.00 84 inch 0.013 392.76 903.09 114.67 106.58 103.25 235.93 1.41 84 inch 0.013 392.76 758.92 114.67 104.16 103.10 35.25 3.01 18 inch 0.013 3.44 18.21 114.67 103.85 103.57 9.25 3.03 18 inch 0.013 3.36 18.27 115.07 102.75 101.56 64.33 1.85 84 inch 0.013 396.19 868.82 115.07 105.00 104.14 56.19 1.53 48 inch 0.013 147.80 177.70 116.00 101.06 99.42 113.13 1.45 84 inch 0.013 543.19 769.12 105.00 99.39 99.00 78.88 0.49 8x5tt 0.013 543.19 428.44 Hunsaker' & Associates San Diego, Inc © Haestad Methods, Inc. 37 Brookside Road Waterbury. CT 06708 USA +1-203-755-1666 ----- HGL HGL In Out (t1) (t1) 146.60 141.48 142.36 141.48 141.49 141.48 140.54 138.62 138.49 138.04 137.55 136.47 136.47 136.47 135.24 123.20 124.96 118.76 119.37 119.31 119.04 118.76 118.76 118.76 117.49 113.38 113.21 112.40 112.43 112.40 112.41 112.40 111.57 111.33 111.92 111.33 109.78 108.96 107.53 106.90 Velocity Velocity In Out (tus) (ftls) 13.34 13.12 4.39 1.64 2.69 2.69 11.00 14.86 11.18 9.38 12.51 10.25 2.41 1.96 12.59 23.65 12.59 10.66 4.45 4.45 5.88 5.88 2.21 2.21 12.75 10.57 10.41 10.21 1.95 1.95 1.90 1.90 10.29 10.29 11.76 11.76 14.11 14.11 13.58 13.58 Project Engineer: H&A Employee StormCAD v5.5 [5.5005] Page 1 of 1 - -- ---.-- --,--Profile Scenario: ALiCANTE ROAD NORTH ALICANTE ROAD NORTH MAIN LINE (NOPES 402-0UTLET) ---r---. ---,-----r----r--- --- ---- ·-....:p..""----~~~j~~~~~--i---------i__----!__----}------~-------.J---.---I------I----.--i .. -----l-----j-------~--.. ----- ·----l160.00 ---1150.00 label: HW-402 Rim: 141.00ft Sump: 134.00 ft label: P-12 Up. Invert 132.43 ft Dn. Invert 130.08 ft l:85.67ft Size: 84 Inch S: 274 % 0+00 1+00 2+00 Title: ALiCANTE ROAD h:\stormcad\2352\141\dwg 397-2tstm 05/15/06 03:00:00 PM 3+00 5+00 6+00 7+00 8+00 9+00 10+00 11+00 12+00 13+00 SIaUon(fl) Hunsaker & Associates San Diego, Inc © Haestad Methods, Inc_ 37 Brookside Road Waterbury, CT 06708 USA +1-203-755-1666. .---~----+---J """ label: P-25 Up. Invert 101.05 ft Dn. Invert 99.42 fi L:l13.13ft Size: 84 Inch S:1.45~ I Elevation (ft) label: P-25 Up. Invert: 99.39 fl Dn. Invert: 99.00 ft L:7!B8fl Size: Bx5ft S: 0.49 % Project Engineer: H&A Employee StormCAD v5_5 [5.5005] Page 1 of 1 POOR QUALITY ORIGINAL S Title: ALICANTE; ROAD h:\stormcad\2352\14'1 \dwg 397 -2f.stm 05/15106 03:00:15 PM '-"_;~_c._,._!,_., ______ _ Label: HW-427 Rim: 110.00 ft Sump: 105.00 ft Profile Scenario: ALiCANTE ROAD NORTH ALiCANTE ROAD NORTH LATERAL (NODES 427-CO) ! --------"-------1120.00 i I i I [--------_ .. _-_._-_._. Label: CO Rim: 115.07 ft Sump: 101.06 ft -------------1 115.00 I i Elevation (ft) 1!ffiL..-.. -------+-I~I·------·-·----·--·--·---·-i 110.00 ~I ---i 105.00 Label: P-24 I Up. Invert: 105.~0 ft Dn.lnvert: 104J4 ft L: 56.19 ft . Size: 48 ihch S: 1.53 % I L ___ . _____ .. ______ ._, ______ m .. __ ........ --.. -.----•• __ -.1 100.00 0+00 0+50 Station (tt) Hunsaker & Associates San Diego, Inc 1+00 ' ©Haestad Methods. Inc. 37 Brookside Road Waterbury; CT 06708 USA +1-203-755-1666 Project Engineer: H&A Employee Storm CAD v5.5 [5.5005] . Page 1 of 1 ~-~'_ " _ i I!IIII -, -. -, ,-_ _ _ ,-_ _ _ _ Title: ALICANTE ROAD h:\stormcad\2352\ 141 \dwg 397 -2f.stm 05/15/06 03:00:34 PM Label: 1-420 Rim: 114.82 ft Sump: 104.16 ft Label: P-21 Up. Invert: 104.16 ft Dn. Invert: 103.10 ft L: 35.25 ft Size:,1.8 inch Profile Scenario: ALiCANTE ROAD NORTH ALICANTE ROAD NORTH , LATERAL (NODES 420-422) --"------------'--"-·'''T-''--------, ---'--'-"---, 120.00 Label: 1-422 Rim: 114.82 ~t Sump: 103.855 ft ~----'~ .-rft-----:--------: --\115.00 i I Elevation (ft) 110.00 a~I-~-------'-------,--1 105.00 Label: P-22 ! Up. Invert: 1 03185 ft Dn. Invert: 1 03157 ft L: 9.25 ft I Size: 18 inch I -~~_~Q3--~~---... -...I100.00 S: 3.01 % . 0+00 0+50 Station (ft) 1+00 Hunsaker & Associates San Diego, Inc © Haestad Methods, Inc. 37 Brookside Road Waterbury. CT 06708 USA +1-203-755-1666 Project Engineer: H&A Employee StormCfl,D v5.5 [5~50051 Page 1 of 1 I I I I I. I I I I I I I I· I L I' , I , , , REVISED HEADWATER DEPTH CALCULATION EXISTING 0-34 HEADWALL AT THE NORTHEAST CORNER OF THE ALiCANTE ROAD-POINSETTIA LANE INTERSECTION 5/15/2006 Given: .Location: Diameter: Discharge: Freeboard: Node 100 0= Q= f= 48 in 147.80 cfs 2.00 ft (From StormCAD output) . (From AES Output) (Minimum requirement) Per Hydraulic Design of Highway Culverts: Appendix D -Design Charts, Tables, and Forms Chart 1 -Headwater Depth for Concrete Pipe Culverts with Inlet Control HW/D= HW= HW= 2.01 96.48 in 8.04 ft Ground Surface Elevation = U/S Culvert Invert (Entrance) = HW Elevation (w/o freeboard) = Actual freeboard: f = 2.71 ft 115.75 ft 105.00 ft 113.04 ft (From storm drain profiles) (From storm drain profiles) HW Elev = 113.04 ft ~ Ground Surface Elev = 115.75 ft H:\EXCEL\2352\141\HW Depth Calc 48-inch.xls I I I I I I I ('.' , I,:, I I I I I , • \~C 16~ 156 144 F1:2.0 -1061 4511 t<.tP G NODEJ..OO (Ef-. \S:.i \ N9 ))-3+ tiwj r: 10,000 -f!',oo<) ~ "5,COO -0,000 4,000 . ~.CrO-O £Xj.;,MPLf. ' o ... :!: I»~J\."~ (3,5 f"'~il Q3 120 d~ (I) ~) (3) E wrra\ i~ c 1::. TYPE Til \l'''~ ~~,;l<lo (:l!) qr (:3) p~el~.;t 1l~ll;~1ilGn1 i" ioQIl14 (11, l,,~~ . nag ltT~l~~~ l~eUf(&1~ Ibl~ t'Wl$;'¥-J~ ~ 4l~..t ~ 1J~1-1Iht", '4)~ rO ... ·'H '&fA S~ ~ itl\!&Hftt~flt { ! ) __ ,J. HEADW,a,1'ER O·E:PTH FOR 181 CONCRETE PiPE CULVERTS ·W~··t' 1...!. I Ii! Ll.:'-I -0 !!I~-..... ; I n i~ '-C:'II~ i RVl... I I I I' I I I I I I I I I I I I I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 9 APPENDICES Appendix 9.5 Excerpts from Drawing No. 397-2F "La Costa Greens -A/ieante Road (North)"~ Sheets 9-11 AH:ad H:IREPORTS\235211461A02.doc W.O.2352·146/170 8121/2006 6:23 AM I I I I '1 I I I I I I I I I I I, I· 1 I ./' ./ ©2002 O'Day Consultants, Inc. " " ... .:. .. _--.• ..... _---.. _-- ~~~~TS 5900 Pwl .... Court Suite 100 CCI1.t1Od. California 92005 71iO-VJI-noo rOle 760-13'1-6580 ....w.ccla,.acznIlllI\lJIItLcorft QyI tnV'l'lI.nnq Plann"', P-. '3~9 "'" .... -... --,.~ / , .' "'-..... .... ._--_.- .. " .... ". ...... . ......... , , '" ", '" ... ~ ...... . ........ .................. '. '. ." ... ,.--~::-'.- PLAN ALICANT£ ROAD = "=#)' OESlONED BY: ~ DAre APRIL 2001 DRAWN BY: J.s Y L SCALE: ~ PROJECT MGR.:...1&-J09 NO.' !I7-10!i7 __________ --11 RCE ENGINEER OF WORK: -:c:CC-..JI l1I\01H'f O. C.II1ROIl DAm "/0'1 RCE: '55381 REVIEWED BY: SPECTOR "AS BUILT" EXP. ___ _ DATE --DA~ H .. l..!. 2 t ::(::;: .. --_ .. _.-.-... -.----- ........ ........ ~ 0' 10' ~' 20' SCALE: 1" • ~O' SEE SHEET No. ~ FOR S//HFACE 1JIP/101S1fNT PlANS SEE SHEET No. 7 FOR SCHe/ oJ: WAIE11 PUNS H ........ ~ ... ~=-I .... ,.~ BENCHMARK: OESC!lIl'l10N: B//ASS OISC IN IIfZL IJIJNUIIlJff (So. CIl CCN1l/OC. PT. 1l11JO(}-28S+89 te) LOCATION: ON !I. CAIJ/NO IlEAl. 2.6.1111. Hi. 'r Fl/OIIIA crurA AISII/£ RECORD FROM: Nll'W/ CQ.IH/'r CONma. ~1i4 ELEVATION: J1U1 DAnni: Nr;'.'!J 19z9 &I' .. /~! ...... fj/l'.L./D'6I~ D.\TE lNl11AL. ENGtNEER OF 'HOlU(i ~0ICe!.C).1\..k:.. lQ{"1"I--\U~~ ~~,~~CJU ~~=~==~ CCNmACTm 7r} I£lffFr 1/£ EXACT LOCAlION OF DlSllNr; IlllllTlES IN THE' FTaD I'RIa? 7r} CCNSlRIJCllON! ~eJ,...Ic:.lu:,e,:..DF~ ~~~I.J.~.,.~. REVISION DESCRIPilON "!III ~ OlHER N'PROV.Il. OAn: I IMI'nAL crTY APPROVAL G,\-UlS\rna:s7~~laJMi I~ !.at5 JII'I CiT _________ ............. _.~ nmJCll!l::~ ..... ~ "".11 .. , 1I'1.1E11-m;lIr.ctNlS TYEf '8-,' INLET NOm /III!lIE' POS!iIlIIE. STEPS SHnJ. BE PlACED IN WAlL Hf1IIour PIP" OPEJIIIIIJ, OlliERIfISE OIEl/ OPEJIIIII: (}f' SIIAlI.£S1" OfIJlC7&. Ji.QIDL EUCTRallC OA iii fll£S ARE FOR REFERENCE ONI.Y I.N/J AR£ NOT 7r) 1£ (JSBJ FOR HOf1IZONTIJ. OR 1£RllCAl. SURVEY CON7ROL I SHEET 1·1 CITY OF CAPT Q'Q An II SHEETS I to ENGiNEERlNQ t c.T.!S-{JS CMWO __ \~I .' ...... [ l \ .......... -. \. . .. ~ .... r"':-~:':-~~' E-~.~O? \ Po~~~TS SOU PalItNl' cau,t . Suit. 100 ec.mbcd, CallfonnCl 9200a 76o-t.l1-17QD rOIl; 7tiG-931-858D __ .odQ~t_tS.::orn eMI £n~I\llerlnq ~-, Pracculng ",,-, .. -...... _.-- L~.?~_~ .. _ ..... _ ....... -.---.. ,._---'-'. . __ .... -'" .. ~ .... " -......... 'g. PLAN st:Al£: ,'=-10' DESIGNED BY: ~ DAlE: ~ "AS BUILT" DRAWN BY: JS. ilL SCI\£: ~ PROJECt' MGR.t....L&:-JOB NO.: g'l-ID51 OAT!: RCE: ___ EXP. ___ _ REVIEWED BY: ~::;:-;;-I'\DDnll~' u;~:. "~;pJ..?~ INSPECTOR DATE ........... :!'.~ ..... . .... BENCHMARK: DESCRIPTIOtl: BRASS O/Sr: IN IffZ1 1I0l/UUENT (.5:IJ. ell COI/lI/OI. pr. HIBIJQ-288+/J9 £1:) LOCITION: ON £1. !iAIIIIIO IlEAl. 2.6J dIZ M. 'r Fl/OI.//A COSTA AVEJIl/£ RECORD fROM: NOR//{ C1XJNrr·COI/lI/OI. DATA ELEVATIO~~ J1f.~l DATUII: NGfrll!12S ~0~.,·,=--~- 0' 10' 40' J:d!!JJ!d!il CONlF/ACTrJR l7) 'd:l?JF't THE EXACT LOCA 1I1J11 OF CXlS7lNG 1J1lUl1!S IN THE fiW PHIOR l7) CONSlRIlCllON! 7YPE '8-1' INLET NOTE: IH/El/£ POSSlIiI£. STEPS SHALl. 8£ PIAc£!) IN IY~LI. '1If1HOflT PIP£ OPENINIl, Oll/El/lllSO Ole.' OPSllNr; Of' S1.t;ll£ST OIAME1El/. NOTE!! EUClRONIC OA TA FlL!S ARE FOR N£mI£NCO ON!. Y AND ARE NOr l7) iJE IISBJ FON HORIZONTAL OR 'rfRllCAL STJH'£'f CONlROl. I ~~'II CITY OF CARLSBAD II SHOEOS I ~==~===~==============:====~I ==-41 ==~===+=~I II ENGINEERING OEPARThlENT 12 I'U8UC STOfIJI fJ//AIN PUNS me: ra./1'Z.ltnal~ ~/r:Lo/o!Jl ~ .... lE IINlTIAL ENGINEER OF WORK 'I\~ ewc.t~~~ ~~~~ REVISION DESCRIPTION Go\.ltlJS\.'I7\!tt1I1:S\,'OZ,JUlJIW ~-IR: 1·:2!Ii!!II .. c:n " 7ii DATE lIN 01l!ER APPROVAL LA COSTA GRE£NS AUCANTF ROAO (NORTH) c:r. g!J-(JJ 'DAlE IlNmAL CIlY APPRGVAI. CMWO __ " 55100 PuIII..-Cwrl , Sun, 100 CGmbGd, CQUfomla nCO!! 7&D-IIJI_noO Fm= 7eQ-9lt-1S680 CIvIl En~=ring PIcnn"'" ---. ---/ .... -~»~< , , .. -,.., // .' / ",," .. '; #' / ... ' -/' /" ." / . / ,,' // 0' 10' 40' ZO~-80' SCPL£: 1· = <\0' f'\"'~ ... ~ .... ~ ~~,I~ ~un.,JGo, lCl'I-r"'\ ~ '!:o\ ~I~u.:. -.J oe,c.o, 00'0.. .,1Z.I::.l ~~-(1~ :f~~~~~g:~~ SEE SHEE1' No. J RJ// StJI1FACE /MPtIOlEMENT PUNS S!E SHEET No. 6 RJ// SE/Ifi/ ok /fA TEI/ Pl.Al/S STORM DRAIN JUNCTION DFTAIL NO spAl£ '<U CArmON II REMARKS #J~O-O arHCP ~ {J5!f:.o 18" RCP ~ {J5D-O RADIUS LENGTH 1601.92' Joo.oo' {{2.61' 128.06' 5oaOO'j J&8{ CONlRAC77JR ro VERIFY 7H£ EXACT £OCA llON OF £)(}S7lNC 1J1lUlI£S IN THe FIELD PRIOR ro CONSTRUC71ONl .1!J)EJ1 8.£CTRONIC OATA FTl£S ARE FOR REFERENCE ONl.Y ANO A/?C NOT ro 8e IJSfl) FOR ffOlllZamI£ OR VEJ?llCAI. st/R'£'t CONTROl. . .ptAN·'~, At/CANTF ROAD = 1"=4fI' ~=i==~=============t====~=+==~==~~I~ICI1~~~G~~~~ADIL1lJ , PrI11lJC srrJIIItI IlIWf( I'/.AHS F1J/f: "AS BUILT" BENCHMARK: DESCl1l1'l10N: 8/IASS = 1/1 IIf!L IlOMIlIENT (S.JJ. ca CON1ROI. pr. i0800-28lJ+1J!1 s:) EXP____ DAn;: LOCAlION: on EJ. CAMINO H£4l. ZSJ ID. Nt. "r f//OIJ LA C!1S'TA A1fIM' RECORD FROLl: NOf/Tf{ COUNTY CONTl/Q. VA rA aEVAlION: 111.~' QATUU: NGWJ 1929 t·v .... · <:::::!:.: REVISION Go\..JmlS\'37t~~,,~ntNO IlHIooW lo3OG:! PI" CT' • ;aID'Sl 91112.1: 8W1l1lI.: Hr:tZoIStR: 1&QUtt\.: KlItJp~ lIaTP3: ~ 1~ t~!IICIlI'\.I.N: JIIaV.U1\. LA COSTA, GREENS AUCANTE ROAO (NORTH) t:.r. 99-()3 CMWO __ I; I I I I I I . ' I 'I , I, I: I I . I I ' I I 'I ii' x I I I I I I I I I I I I I I I :1 I I I Drainage Study Developer Improvements La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 10 HYDROLOGY EXHIBITS Exhibit 10.1 Developed Condition Hydrology Map AH:ad H:\REPORTS\2352\146\A02.doc W.O.2352·1461170 812112006 8:23 AM ..... ,.. / 1- LEGEND PROJECT BOUNDARY WATERSHED BNDY WATERSHED ID NODE DRAINAGE DIRECTION -.---------.--- EXISTING STORM DRAIN PROPOSED STORM DRAIN == =tQ]== == ==== CITY OF ENCINITAS VICINITY MAP NTS / / / / / / I I / I I-I I ( I ~,.o, /1 ~ -/ , ' , --, BASIN #2: ~~. /d NEIGHBORHOOD 1.3 Q_= 10.gcfs. / /~ .. -. I , I i l , '".;r' ., ----- 1.3 FUTURE MUL TI-FAMIL RESIDENTIAL SITE i f ( \ \ .H&A 8/5/2008 CAMINO VIDA ROBLE ~- --------. ---~ -- IGHBORHOOD 1.3 . FUTURE MULTI-FAMILY SITE -~- I I . \ \ \ , \ \ \ \ , , \ \ " \ PREPARED BY: HUNSAKER & ASSOCIATES SAN DI£Co, INC PLANNING 10179 Huennekens Street ENGINEERING San Diego. Ca 92111 SURVEYING PH(856)558-4500· FX(85B)5-5U·1414 DEVELOPED CONDITION HYDROLOGY MAP FOR LA COSTA GREENS NEIGHBORHOODS 1.2 & 1.3 DEVELOPER IMPROVEMENTS XHIBIT 10.1 CITY OF CARLSBAD, CALIFORNIA c SHEET 1 OF 1 R:\0510\&Hyd\0510$H08-NEIGH 1.2 & 1.3-FE-INT100.dwg[ 7692]Aug-21-2006: 11:53 -T , c. ,-. ~, e, "" 0 '" LEGEND PROJECT BOUNDARY EXISTING HCP LINE WATERSHED BNDY DRAINAGE DIRECTION LOCATION 10 NODE EXISTING STORM DRAIN -------- ---.. -. ----. o PROPOSED STORM DRAIN =-~-===== o 100 200 300 ~SCALE 1"= 100~1, __ ~I i i , ! ~ ~Wl' 6" ! , i / tYV...J .-. . i "$£,4 .j . ~ n: . , Q 100 = B. 7 cfs. A= 1.7 oc. Te = B.1 min. \\ \ \, 0 100 = 37. 6 cfs. A= 10.0oc. Ta = 9.0 min. ~\ 0 100 = 4.2cfs. A=O.90c. Ta = 10.4 min. PREPARED BY: HUNSAKER & ASSOCIATES SAN DlfCO, INC PLANNING 10179 Huennekens Street ENQNEERING San Diego, Ca 92121 SURVEYING PH(858)558-4500· FX(858)558-1414 H&A 8/5/2008 MASS-GRADED HYDROLOGY MAP FOR LA COSTA GREENS NEIGHBORHOODS 1.1-1.3 CITY OF CARLSBAD, CALIFORNIA SHEET 1 OF 2 R: \0510\&Hyd\0510$H02-MG100.dwg[O]Jan-24-2005: 19: 35 '" '" I N '" '" N ... d ,,; , , , o 100 200 300 ~=---~ ; i ' ; , i : , , . , , ! . \ . SCALE 1" -10D~ ! .' ---.~."', I' i ! .$,,. I ! 1/,,-., ,.,"'I .... ~~7 I ~~~" , '. \ ' , \ \ ",m,~ "",-p " f ~~.0 \ ./ ~~-< Q lOa = 20.8 cfs. A= 5.9 ac. Tc =14.9 min. \~ ) SEE SHEET l' H&A 8/5/2008 HCP Q'OO=74.8cfs. A= 43.4 ac. Tc =18.5 min. '----' - .....-.-HCP .. "'. I '1 I I -4 .. -r; / / HUNSAKER ) -4 I ! & ASSOClA TES SAN DIFGO, INC PlANNING 10179 Huennekens Street ENGINEERING San Diego, Ca 92121 SURVEYING PH(85B)558-4500' FX(858}55a-1414 Q'00 = 178.2 cfs. A=91 . .3 ac. Tc =14.8min. ( LEGEND PROJECT BOUNDARY EXISTING HCP LINE WATERSHED BNDY DRAINAGE DIRECTION LOCATION 10 NODE EXISTING STORM DRAIN -------- ---o ='==-~::':":"== ........... ~ ....... - PROPOSED STORM DRAIN --~-======= MASS-GRADED HYDROLOGY MAP FOR LA COSTA GREENS NEIGHBORHOODS 1.1-1.3 CITY OF CARLSBAD, CALIFORNIA \, \ \ SHEET 2 OF 2 R:\D510\&Hyd\0510$H02-MG100,dwg[ O]Jan-24-2005:20:34 '" "' I N '" '" N "" 0 '" PROJECT SITE9~ x 298,9 NTS ---------, I I I I I I I II I I " II ® :: 'Sr)f~'y.2P~1~~'1 310.5 II II I I I I ~ .---- /1 ! ~.--, A= 5.3 oc. Te = B.2 min. 0.57 ACRES: CD 310.2 " " ji 11.9 310.7 LEGEND SCALE 1" WATERSHED BOUNDARY 40' SUBAREA BOUNDARY NODES ------ I , I , ( <J~ 311.7 / , j ! , ! I / , ! 1 . \ \ \ , j i \ \ \ ( CD 313.5 PREPARED FOR: HUNSAKER & ASSOCIATES SAN DIEGO. INC PLANNING 9707 Waples Street ENGINEERING San Diego, Ca 92121 SURVEYING PH(B5B)55B-4500' FX(B5B)55B·1414 H&A 8/5/2008 /'J n ,,// /> \ ® " 323.1 14 ACRES @ 322.5 I . I I I '~I_~ • .L~_~~------.• ~-------~--r Q 100 = 2.7 cfs. A= O.B ac. T;; = 6.4 min. @ 323.7 I \ I \ f I \ \ i ( \ ~ @ 320.4 @ 320.9 \ .\ \ \ \ '\ \\ \ v, o G ) \ \ , \, , , ® 320.6 @ 320.1 ® 319.9 @ 320.1 0.55 ACRES C@' 320.7 DEVELOPED CONDITION HYDROLOGY MAP FOR I La Costa Greens N. 1.3 CITY OF CARLSBAD, CALIFORNIA i I \ , , \ \ I j 1 ! I I I , I \ , I I i i I ) , \ , \ \ \ l \ \ 120 R:\0510\&Hyd\0510$H15-DEV-1.3-HYDRO.dwg[]Apr-08-2008: 09: 31 \ \ \ \ I I \ 1 \ MAP 1 OF 1 I I I I I I I I I I I I I I II i ,I i I 'I Drainage Study Developer Improvem~nts " La Costa Greens Neighborhoods 1.2 & 1.3 CHAPTER 10 HYDROLOGY EXHIBITS Exhibit 10.2 Site Exhiibit AH:ad H:IREPORTS123521146\A02.doc ' W.O.2352-146/170 812112006 8:23 AM , -" LEGEND PROJECT BOUNDARY ------ DRAINAGE DIRECTION ----------------- EXISTING STORM DRAIN PROPOSED STORM DRAIN == =12]1== == === _-r PROJECT SITE CITY OF ENCINITAS " CITY OF SAN MARCOS VICINITY MAP o 150 300 ~ I SCALE 1"= 150' PREPARED BY: HUNSAKER & ASSOCIATES SAN DI£(;O INC PLANNING 10179 Huennekens Street ENQNEERING San Diego, Ca 92121 SURVEYING PH(858)558 4500· FX(858)55&1414 NTS 450 XHIBIT 10.2 SITE EXHIBIT LA COSTA GREENS NEIGHBORHOODS 1 .2 & 1.3 DEVELOPER IMPROVEMENTS CITY OF CARLSBAD, CALIFORNIA '- SHEET 1 OF 1 H&A Sf2li2006 { -1 ---r / .( " I -1 I /: ;' =-1/ '>= .. ~""'~ F _,*-~ '1 / '\. ' ""'-' EXISTING D":34 HEADWALL '/ " ~ ~,,\>'I ; \ I ,,,,--' --\ 'Ii , ,'f; ,'/ IV 1 ! ~~¥:t < f / /J /f I' :If 'u / TO BA TlSQUITOS / LAGOON & It'" PACIFIC OCEAN f ,/ f < / "< /---;. ; \ "..4«s~ f'> ; "1 ~ /' , ...... ~, f f ,"f '::'/ , I AUCANTE DETENTION BASIN - I ,., L ,_. I ~. I .n ~\0510\&Hyd\0510$HOB-NEIGH 1.2 & 1,3-FE-INT100.dwg[ 7692]Aug-21-2006: 11:54 :;; I N en '" N "" 0 "