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CDP 2020-0001; PATEL RESIDENCE; DRAINAGE STUDY; 2021-01-07
DRAINAGE STUDY PATEL RESIDENCE TERRAMAR, CARLSBAD BOULEVARD CITY OF CARLSBAD CDP 2020-0001 CDP 2020-0013 GR 2020-0001 DWG 526-6A Prepared for: Rajesh Patel Vagha Development LLC 3170 Vista Way Oceanside, CA 92056 Prepared by: bha, Inc land planning, civil engineering, surveying 5115 Avenida Encinas, Suite L Carlsbad, CA 92008-4387 (760) 931-8700 January 7, 2021 W.O. 1085-1458-600 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 2 TABLE OF CONTENTS I. DISCUSSION Vicinity Map…………………………………..…………... 4 Purpose and Scope………………………………….…….. 5 Project Description……………………………………….. 5 Study Method……………………………………………... 6 Conclusions……………………………………………….. 8 Declaration of Responsible Charge………………….….. 9 II.EXHIBITS Pre-Developed Hydrology Map & Post-Developed Hydrology Map…………………….… 10 III.HYDROLOGY & HYDRAULIC CALCULATIONS HYDROLOGY CALCULATIONS……………………. 11 Pre-Developed Hydrology Calculations…………..…… 12 Undetained Post-Developed Hydrology Calculations……………………………………………… 15 Detained Post-Developed Hydrology Calculations…………….………………………………… 20 6-inch and 8-inch Pipe Calculations..…………………… 25 HYDRAULIC CALCULATIONS………………..…. 28 Basin Outlet Detail……………………………............... 29 Storage and Capacity Calculations and 85th Percentile Volumes…….………………...……….... 30 Storage Basin Hydrograph Routing Models…………. 39 IV.REFERENCES Precipitation Frequency Estimates…………………… 51 Web Soils Survey…………………………………….…… 55 San Diego County Hydrology Manual …………….… 59 Reference Drawings (Dwg No. 270-2) ……………….. 70 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 3 I. DISCUSSION Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 4 PACIFIC OCEAN NOT TO SCALE CEREZO DRIVE Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 5 PURPOSE AND SCOPE: The purpose of this report is to publish the results of a hydrology and hydraulic analysis for the proposed residential project along Carlsbad Boulevard, near Terramar Beach in the City of Carlsbad, APN 210-115-08. The proposed project is a 0.166-acre site. The scope is to study pre- developed and post-developed hydrology and hydraulics as it influences the surrounding properties during an 100-year frequency storm event, and make recommendations to intercept, contain and convey runoff to the historic point of discharge. PROJECT DESCRIPTION: The project is located along Carlsbad Boulevard between Cerezo Drive and Manzano Drive. The proposed project is a 0.166 acre site. The project proposes the development of a two story single family residence with an underground garage. The disturbed area is 0.166 acres; the existing site is 0% impervious pre-development. The developed drainage basin matches the existing drainage basin in terms of overall area and basin limits. Storm flows affecting the site are limited to the rainfall that lands directly on this property and drainage from the easterly abutting properties that flow across the subject property. The following table summarizes the pre-developed condition runoff information from the site. Please refer to the Pre-developed Condition Hydrology Map for existing drainage area. TABLE 1—Summary of Pre-Developed Condition Peak Flows 100 YEAR 0.333 0.72 STORM EVENT AREA (ac)PEAK FLOW (cfs) The post-developed drainage pattern will be similar as the pre-developed drainage pattern with some modifications to incorporate the Best Management Practices (BMPs) into the project design to mimic the impacts on storm water runoff and quality. The post-developed runoff from the project will gravity flow toward Carlsbad Boulevard. Prior to discharging from the project site, low impact development strategies (site design bmps) will be incorporated into the site design. Post-developed site runoff from impervious areas such as rooftops and walkways will be directed onto the impervious dispersion areas. The intent is to slow runoff discharges and reduce volumes while achieving incidental treatment. Runoff will then surface flow to Carlsbad Boulevard and eventually to an existing curb inlet in Carlsbad Boulevard approximately 45 feet to the north. Impervious surfaces have been minimized where feasible. Post-developed drainage patterns will not alter the existing flow pattern and will discharge from the site to the historic discharge location. Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 6 A portion of the driveway slopes easterly from Carlsbad Boulevard into the covered garage. This runoff is collected in a trench drain and conveyed into a lift station located in the garage and pumped via a 2-inch force main to the front planter area adjacent to Carlsbad Boulevard. Approximately 255 square feet of driveway drains towards the trench drain (0.04 cfs). See calculations for runoff on Post-Developed Hydrology Map. Table 2 summarizes the expected cumulative undetaned 100-year peak flow rate from the post- developed site. TABLE 2—Summary of Post-Developed Condition Peak Flows 100 YEAR 0.333 1.11 STORM EVENT AREA (ac)PEAK FLOW (cfs) STUDY METHOD: The method of analysis was based on the Rational Method according to the San Diego County Hydrology Manual. The Hydrology and Hydraulic Analysis were done on HydroSoft by Advanced Engineering Software 2014. Design Storm – 100-year return interval Land Use – Residential Soil Type — The site was modeled with Type B hydrologic soils as determined from the NRCS Web Soil Survey. Type B soils have moderate infiltration rates when thoroughly wetted. Rainfall Intensity – Initial time of concentration (Tc) values based on Table 3-2 of the San Diego County Hydrology Manual (SD HM). Rainfall Isopluvial Maps from the SD HM were used to determine P6 for 100 year storm, see references. Rainfall Intensity = I = 7.44x(P6)x(Tc)- 0.645 P6 for 100 year storm = 2.51 inches In accordance with the County of San Diego standards, runoff coefficients were based on land use and soil type. An appropriate runoff coefficient (B) for each type of land use in the subarea was selected from Table 3-1 of San Diego Hydrology Manual multiplied by the percentage of total area (A) included in that class. The sum of the products for all land uses is the weighted runoff coefficient (∑ [CA]). For the pre-developed and post-developd conditions, a runoff coefficient of 0.30 was selected for all Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 7 landscaped and pervious areas assuming 0% impervious. In the developed conditions, the concrete and roof areas were considered 95% impervious and assigned a runoff coefficient of 0.87. The exhibits show the offsite area, proposed on-site drainage system, on-site subareas, and nodal points. Table 3 summarizes the composite C-values calculated in the pre-developed condition hydrology and post-developed Conditions. TABLE 3 - Weighted Runoff Coefficient Value Calculations for Pre-Developed and Post-Developed Condition Peak Flows Up Node Down Node Total Area (ac)C1 A1 (acres)C2 A2 (acres)Ccomp 10 20 0.111 0.30 0.030 0.87 0.081 0.72 20 30 0.056 0.30 0.036 0.87 0.020 0.50 30 40 0.166 0.30 0.166 0.87 0.000 0.30 Up Node Down Node Total Area (ac)C1 A1 (acres)C2 A2 (acres)Ccomp 10 20 0.111 0.30 0.030 0.87 0.081 0.72 20 30 0.056 0.30 0.036 0.87 0.020 0.50 30 40 0.107 0.30 0.052 0.87 0.055 0.59 33 33 0.038 0.30 0.000 0.87 0.038 0.87 35 35 0.021 0.30 0.000 0.87 0.021 0.87 Pre‐Developed Hydrology Post‐Developed Hydrology Note: C‐values taken from Table 3‐1 of San Diego County Hydrology Manual, consistent with on‐site existing soil types. See References. Developed condition peak flows were calculated using the modified rational method. The majority of the roof runoff is conveyed into raised biofiltration planter boxes (Biofiltraion Basin 1 and Biofiltration Basin 2) at each back corner of the residential structure in the rear yard via roof down spouts. Runoff routed through the raised biofiltration planter boxes are modeled with HEC-HMS. The Modified-Puls detention routing analyzes existing and developed condition 100-year peak flow rates for the biofiltration basins ensures that post-development peak flow is less than or equal to pre-development peak flow for the 6-hour 100-year storm event at the project’s point of compliances (POC-1). The Modified-Puls results are summarized in Table 4 below. HEC-HMS allows for hydrology input time steps of 1, 2, 3, 4, 5, 10, 15 & 20 minutes. Rational Method analysis input was used to determine an inflow hydrograph using the 2/3’s 1/3 distribution as detailed on pages 4-2 and 4-3 of the 2003 County of SD HM. The time of concentration (Tc) used for the construction of these hydrographs was rounded to the nearest time interval that HEC- HMS could accept. In addition to detaining runoff, the biofiltration basins provide pollutant control. Storage provided in the biofiltration layers of the basin consist of engineered fill soil layer and the underlying gravel base layer. As HEC-HMS uses an elevation-storage-discharge function to model the basin volume (stage-storage) and basin discharge (stage-discharge) relationships, the available storage volume Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 8 provided by these aforementioned sub-layers is accounted for by reducing the total sub-basin volume by the corresponding void ratio for each layer (0.4 for gravel and 0.2 for soil respectively). It should be noted that as a conservative design approach, it has been assumed that the 85th percentile water quality event volume was stored in the biofiltration basins prior to the routing of the 100-year storm event. The volume is a conservative hydraulic design methodology only. See Hydraulic Calculations for storage volume calculations. Rational method hydrographs, stage- storage, stage-discharge relationships and HEC-HMS model output is provided in calculations section of this report. See the comparison of pre-developed condition hydrology and post-developed condition hydrology in Table 4 below. TABLE 4 - Summary of Pre-Developed and Post-Developed Condition Peak Flows 100 YEAR 0.330 0.72 1.11 0.13 STORM EVENT 0.85 AREA (ac) PRE‐DEVELOPED PEAK FLOW (cfs) UNDETAINED POST‐DEVELOPED PEAK FLOW (cfs) DETAINED POST‐DEVELOPED PEAK FLOW (cfs) DIFFERENCE (cfs) CONCLUSIONS: As shown in Table 4, the development of the proposed Patel Residence project site will result in a net increase of peak flow discharged from the project site 0.13 cfs during a 100-year storm event. However this increase is considered negligible to the overall drainage discharged into the public storm drain downstream where an existing curb inlet located along Carlsbad Boulevard intercepts runoff. In addition landscaping areas, impervious dispersion areas (including the decomposed granite parkway in Carlsbad Boulevard will slow runoff discharges further to reduce runoff to pre- developed conditions. These small collection techniques foster opportunities to maintain the existing hydrology and provide a much greater range of retention practices. The developed site will also implement source control and site design BMPs in accordance with the “Standard Project” stormwater requirements. Peak flow rates listed above were generated based on criteria set forth in SD HM presented in this report. The hydraulic calculations show that the proposed onsite storm drain facilities can sufficiently convey the anticipated runoff without any adverse effects. Based on this conclusion, runoff released from the proposed project site will unlikely cause any adverse impact to downstream water bodies or existing habitat integrity. Sediment will likely be reduced upon site development. Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 9 DECLARATION OF RESPONSIBLE CHARGE I hereby declare that I am the Engineer of Work for this project, that I have exercised responsible charge over the design of the project as defined in section 6703 of the business and professions code, and that the design is consistent with current standards. I understand that the check of project drawings and specifications by the City of Carlsbad is confined to a review only and does not relieve me, as Engineer of Work, of my responsibilities for project design. Ron Holloway R.C.E. 29271 Date Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 10 II.EXHIBITS PRE-DEVEOPED HYDROLOGY MAP & POST-DEVELOPED HYDROLOGY MAP 30 0.50 C=0.50 0.056 K:\Civil 3D\1458\DWG\HYDRO\1458_EXIST_HYDROLOGY_EXHIBIT.dwg, 12/1/2020 9:13:13 AM 51.6 EP 51.6 -EP EXIS11NG STORM DRAIN ,,,.,.,,,, ,,, r =-, I ~ D :r: ~ i-----+~1_.i;~ij7'~-~'--EX/S11NG CURB INLET PER " DWG 214-4 ~ (51.J2 TC) I I I 1 I 51.4 ! i-coNC- ! \7 I q I 1 f 51,b ,~ I I s1 I I I I 51.5 °i' ( 48.JO IE±) ~ t -coNC- L. I~ 52.6 -DIRT ~ -~ -DIR' I PROPERTY LINE 53,8 -D1RT 55,0 ,..-DIRT ' I I . < PROPERTY LIN 8.7 -DIRT - f JO \ ( r \n I ----~ I /~J ~ - - - - - - - - -.. -- - - - - - - - -__ \ __ ---:::, -+ic'a-- ---- - - - -.. I 51.6 ~ EP 100' ui I 51,6 o -coNC, -a ~ I t :1-----------~50!_.' __ -+--------i---+'-_A_c __ l-------'5~0~' -+'°"+-l--__:/:--~e,---- 1 I ~ ~ ~ 51.6 -EP ~ \ "' 17.5± ' I ~· ± t I I I <J 18' ± " 51,6 -coNC, 53.0 -DIRT LEGEND SURFACE NODE SURFACE RUNOFF 100 YEAR STORM EVENT (CFS) BASIN AREA (ACRES) RUNOFF COEFFICIENT BASIN BOUNDARY /SUB-BOUNDARY ~ DIRT C) <" PROJECT BOUNDARY ------0 PACIFIC Cf' OCEAN ~ ~ SITE- NOT TO SCALE CEREZO DRIVE FLOWLINE -~ -DIR' . .MJ...--DIR' ' 5 .6 ~ oRT B I ' I I 56.0 -p1RT GB 1 o· . [ C . I . ' □ . I 2c I i ' [] 5' o· -\ 1 o· SCALE: 1" = 59.0 -DJRI :y 10' 20' DA TE OF PREPARATION: REVISIONS DESCRIPTION 30' DATE rio\ /~ @I) C-0.72 ------------------- - bl-lA,lnc. land planning. clvll engineering, suiveylng 5115 AVENIDA ENCINAS SUITE "L" CARLSBAD, CA. 92008-4387 (760) 931-8700 CDP 2020-0001 CDP 2020-0013 GR2020-0001 DWG526-6A PRE-DEVELOPED HYDROLOGY PATEL RESIDENCE TERRAMAR CARLSBAD BOULEVARD CITY OF CARLSBAD, CALIFORNIA SHEET 1 OF 1 SHEETS 30 0.50 C=0.50 0.056 K:\Civil 3D\1458\DWG\HYDRO\1458_PROP_HYDROLOGY_EXHIBIT-GP.dwg, 12/1/2020 10:32:01 AM PACIFIC OCEAN ~ ~ NOT TO SCALE CEREZO DRIVE C' 51.6 -EP 51.6 -EP 51.6 -EP 51.6 ~EP EXISllNG STORM DRAIN • """"'' ,.,, T ,,,,_, I I ~ AC ~ AC I ~ AC I I 51.9 -AC LEGEND SURFACE NODE U) 0 ~ ~ V) 0 ~ ~ V) 0 ~ ~ V) 0 ~ ~ V) 0 ~ I ; ; ~ , coN • <1~ 4 4 L] q L] 4 q ' 4. q q L] q A ~:v., /CON <J ~1-~ -COi C. kl 51.6 i--coNC-, SURFACE RUNOFF 100 YEAR STORM EVENT (CFS) BASIN AREA (ACRES) RUNOFF COEFFICIENT BASIN BOUNDARY /SUB-BOUNDARY PROJECT BOUNDARY FLOVvUNE 0 --- q 4 C 5Ut,tP PUMP RUNOFF P6 = 2.51, 1C = 5 MIN, I = 6.61 Q • aA • 0.95 X 6.61 X 255/43560 • 0.04 CfS FACTOR OF SAFTEY = 2. Q = 0.08 CfS I / PROPERTY UNE 53.0 ,_ DIRT A PROPERTY U IMPERVIOUS AREA: ~ BUILDING / ROOF ~ POOL AREA I 4q 4 I CONCRETE I ./, 4 4] DRIVEWAY 14• q I DRIVEWAY (OFF-SITE) 4 ~ GROUTED PAVERS TOTAL 3,367 SF 1,011 SF 51 SF 235 SF 217 SF 98 SF 4,979 SF I I I I I I I I I " -~ ~DIR• PERVIOUS AREA: I " j "" "' LANDSCAPE "' 1: ; : ; : ; : ; : ; PERVIOUS PAVERS I DECOMPOSED GRANITE ~~;~;~;~j BIOFIL 1RA TION BASIN (EXCLUDING COVERED AREAS) TOTAL ~ D I '1 I ;:'I ~T 23 DIR I I (JO\ V 0.50_) @) C=0.50 ------~-----... ~--------- 1,871 SF 469 SF 49 SF 101 SF 2,490 SF REVISIONS 59.0 -DIRT \ ,;g.3 - _5!Ll,- -----01RT DA TE OF PREPARATION: DESCRIPTION DATE ------- 1 o· 5' o· ---1 o· 20' 30• CDP 2020-0001 ----CDP 2020-0013 GR2020-0001 DWG526-6A SCALE: 1'' = 1 O' bl-lA,lnc. land planning. clvll engineering, suiveylng 5115 AVENIDA ENCINAS SUITE "L" CARLSBAD, CA. 92008-4387 (760) 931-8700 POST DEVELOPED HYDROLOGY EXHIBIT PATEL RESIDENCE TERRAMAR CARLSBAD BOULEVARD CITY OF CARLSBAD, CALIFORNIA SHEET 1 OF 1 SHEETS Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 11 III. HYDROLOGY CALCULATIONS Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 12 PRE-DEVELOPED HYDROLOGY CALCULATIONS Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 13 ____________________________________________________________________________ **************************************************************************** RATIONAL METHOD HYDROLOGY COMPUTER PROGRAM PACKAGE Reference: SAN DIEGO COUNTY FLOOD CONTROL DISTRICT 2003,1985,1981 HYDROLOGY MANUAL (c) Copyright 1982-2014 Advanced Engineering Software (aes) Ver. 21.0 Release Date: 06/01/2014 License ID 1459 Analysis prepared by: BHA INC. 5115 AVENIDA ENCINAS, SUITE L CARLSBAD, CA 92008 ************************** DESCRIPTION OF STUDY ************************** * EXISTING HYDROLOGY * * * * * ************************************************************************** FILE NAME: K:\HYDRO\1458\1458E1.DAT TIME/DATE OF STUDY: 15:37 05/02/2020 ---------------------------------------------------------------------------- USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION: ---------------------------------------------------------------------------- 2003 SAN DIEGO MANUAL CRITERIA USER SPECIFIED STORM EVENT(YEAR) = 100.00 6-HOUR DURATION PRECIPITATION (INCHES) = 2.510 SPECIFIED MINIMUM PIPE SIZE(INCH) = 4.00 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 30.0 20.0 0.018/0.018/0.020 0.67 2.00 0.0313 0.167 0.0150 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.* **************************************************************************** FLOW PROCESS FROM NODE 10.00 TO NODE 20.00 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< ============================================================================ *USER SPECIFIED(SUBAREA): USER-SPECIFIED RUNOFF COEFFICIENT = .7200 S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET) = 70.00 UPSTREAM ELEVATION(FEET) = 59.90 DOWNSTREAM ELEVATION(FEET) = 59.20 ELEVATION DIFFERENCE(FEET) = 0.70 SUBAREA OVERLAND TIME OF FLOW(MIN.) = 5.723 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 14 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.062 SUBAREA RUNOFF(CFS) = 0.35 TOTAL AREA(ACRES) = 0.08 TOTAL RUNOFF(CFS) = 0.35 **************************************************************************** FLOW PROCESS FROM NODE 20.00 TO NODE 30.00 IS CODE = 51 ---------------------------------------------------------------------------- >>>>>COMPUTE TRAPEZOIDAL CHANNEL FLOW<<<<< >>>>>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 59.20 DOWNSTREAM(FEET) = 58.10 CHANNEL LENGTH THRU SUBAREA(FEET) = 35.00 CHANNEL SLOPE = 0.0314 CHANNEL BASE(FEET) = 0.00 "Z" FACTOR = 20.000 MANNING'S FACTOR = 0.030 MAXIMUM DEPTH(FEET) = 0.50 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.792 *USER SPECIFIED(SUBAREA): USER-SPECIFIED RUNOFF COEFFICIENT = .5000 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 0.43 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) = 1.39 AVERAGE FLOW DEPTH(FEET) = 0.12 TRAVEL TIME(MIN.) = 0.42 Tc(MIN.) = 6.14 SUBAREA AREA(ACRES) = 0.06 SUBAREA RUNOFF(CFS) = 0.16 AREA-AVERAGE RUNOFF COEFFICIENT = 0.630 TOTAL AREA(ACRES) = 0.1 PEAK FLOW RATE(CFS) = 0.50 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH(FEET) = 0.13 FLOW VELOCITY(FEET/SEC.) = 1.42 LONGEST FLOWPATH FROM NODE 10.00 TO NODE 30.00 = 105.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 30.00 TO NODE 40.00 IS CODE = 51 ---------------------------------------------------------------------------- >>>>>COMPUTE TRAPEZOIDAL CHANNEL FLOW<<<<< >>>>>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 58.10 DOWNSTREAM(FEET) = 52.50 CHANNEL LENGTH THRU SUBAREA(FEET) = 105.00 CHANNEL SLOPE = 0.0533 CHANNEL BASE(FEET) = 0.00 "Z" FACTOR = 20.000 MANNING'S FACTOR = 0.030 MAXIMUM DEPTH(FEET) = 0.50 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.268 *USER SPECIFIED(SUBAREA): USER-SPECIFIED RUNOFF COEFFICIENT = .3000 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 0.63 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) = 1.80 AVERAGE FLOW DEPTH(FEET) = 0.13 TRAVEL TIME(MIN.) = 0.97 Tc(MIN.) = 7.11 SUBAREA AREA(ACRES) = 0.17 SUBAREA RUNOFF(CFS) = 0.26 AREA-AVERAGE RUNOFF COEFFICIENT = 0.449 TOTAL AREA(ACRES) = 0.3 PEAK FLOW RATE(CFS) = 0.72 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH(FEET) = 0.13 FLOW VELOCITY(FEET/SEC.) = 1.98 LONGEST FLOWPATH FROM NODE 10.00 TO NODE 40.00 = 210.00 FEET. ============================================================================ END OF STUDY SUMMARY: TOTAL AREA(ACRES) = 0.3 TC(MIN.) = 7.11 PEAK FLOW RATE(CFS) = 0.72 ============================================================================ ============================================================================ END OF RATIONAL METHOD ANALYSIS Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 15 UNDETAINED POST-DEVELOPED HYDROLOGY CALCULATIONS Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 16 ____________________________________________________________________________ **************************************************************************** RATIONAL METHOD HYDROLOGY COMPUTER PROGRAM PACKAGE Reference: SAN DIEGO COUNTY FLOOD CONTROL DISTRICT 2003,1985,1981 HYDROLOGY MANUAL (c) Copyright 1982-2014 Advanced Engineering Software (aes) Ver. 21.0 Release Date: 06/01/2014 License ID 1459 Analysis prepared by: BHA INC. 5115 AVENIDA ENCINAS, SUITE L CARLSBAD, CA 92008 ************************** DESCRIPTION OF STUDY ************************** * UNDETAINED PROPOSED HYDROLOGY * * * * * ************************************************************************** FILE NAME: K:\HYDRO\1458\1458P1.DAT TIME/DATE OF STUDY: 09:38 12/01/2020 ---------------------------------------------------------------------------- USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION: ---------------------------------------------------------------------------- 2003 SAN DIEGO MANUAL CRITERIA USER SPECIFIED STORM EVENT(YEAR) = 100.00 6-HOUR DURATION PRECIPITATION (INCHES) = 2.510 SPECIFIED MINIMUM PIPE SIZE(INCH) = 4.00 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 30.0 20.0 0.018/0.018/0.020 0.67 2.00 0.0313 0.167 0.0150 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.* **************************************************************************** FLOW PROCESS FROM NODE 10.00 TO NODE 20.00 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< ============================================================================ *USER SPECIFIED(SUBAREA): USER-SPECIFIED RUNOFF COEFFICIENT = .7200 S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET) = 70.00 UPSTREAM ELEVATION(FEET) = 59.90 DOWNSTREAM ELEVATION(FEET) = 59.20 ELEVATION DIFFERENCE(FEET) = 0.70 SUBAREA OVERLAND TIME OF FLOW(MIN.) = 5.723 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 17 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.062 SUBAREA RUNOFF(CFS) = 0.35 TOTAL AREA(ACRES) = 0.08 TOTAL RUNOFF(CFS) = 0.35 **************************************************************************** FLOW PROCESS FROM NODE 20.00 TO NODE 30.00 IS CODE = 51 ---------------------------------------------------------------------------- >>>>>COMPUTE TRAPEZOIDAL CHANNEL FLOW<<<<< >>>>>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 59.20 DOWNSTREAM(FEET) = 58.10 CHANNEL LENGTH THRU SUBAREA(FEET) = 35.00 CHANNEL SLOPE = 0.0314 CHANNEL BASE(FEET) = 0.00 "Z" FACTOR = 20.000 MANNING'S FACTOR = 0.030 MAXIMUM DEPTH(FEET) = 0.50 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.792 *USER SPECIFIED(SUBAREA): USER-SPECIFIED RUNOFF COEFFICIENT = .5000 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 0.43 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) = 1.39 AVERAGE FLOW DEPTH(FEET) = 0.12 TRAVEL TIME(MIN.) = 0.42 Tc(MIN.) = 6.14 SUBAREA AREA(ACRES) = 0.06 SUBAREA RUNOFF(CFS) = 0.16 AREA-AVERAGE RUNOFF COEFFICIENT = 0.630 TOTAL AREA(ACRES) = 0.1 PEAK FLOW RATE(CFS) = 0.50 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH(FEET) = 0.13 FLOW VELOCITY(FEET/SEC.) = 1.42 LONGEST FLOWPATH FROM NODE 10.00 TO NODE 30.00 = 105.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 30.00 TO NODE 40.00 IS CODE = 51 ---------------------------------------------------------------------------- >>>>>COMPUTE TRAPEZOIDAL CHANNEL FLOW<<<<< >>>>>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 58.10 DOWNSTREAM(FEET) = 52.90 CHANNEL LENGTH THRU SUBAREA(FEET) = 105.00 CHANNEL SLOPE = 0.0495 CHANNEL BASE(FEET) = 0.00 "Z" FACTOR = 20.000 MANNING'S FACTOR = 0.013 MAXIMUM DEPTH(FEET) = 0.50 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.516 *USER SPECIFIED(SUBAREA): USER-SPECIFIED RUNOFF COEFFICIENT = .5900 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 0.67 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) = 3.63 AVERAGE FLOW DEPTH(FEET) = 0.10 TRAVEL TIME(MIN.) = 0.48 Tc(MIN.) = 6.62 SUBAREA AREA(ACRES) = 0.11 SUBAREA RUNOFF(CFS) = 0.35 AREA-AVERAGE RUNOFF COEFFICIENT = 0.613 TOTAL AREA(ACRES) = 0.2 PEAK FLOW RATE(CFS) = 0.82 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH(FEET) = 0.11 FLOW VELOCITY(FEET/SEC.) = 3.43 LONGEST FLOWPATH FROM NODE 10.00 TO NODE 40.00 = 210.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 40.00 TO NODE 40.00 IS CODE = 1 ---------------------------------------------------------------------------- >>>>>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE<<<<< ============================================================================ TOTAL NUMBER OF STREAMS = 3 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 18 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 1 ARE: TIME OF CONCENTRATION(MIN.) = 6.62 RAINFALL INTENSITY(INCH/HR) = 5.52 TOTAL STREAM AREA(ACRES) = 0.24 PEAK FLOW RATE(CFS) AT CONFLUENCE = 0.82 +--------------------------------------------------------------------------+ | BIOFILTRATION BASIN 1 | | | | | +--------------------------------------------------------------------------+ **************************************************************************** FLOW PROCESS FROM NODE 33.00 TO NODE 33.00 IS CODE = 7 ---------------------------------------------------------------------------- >>>>>USER SPECIFIED HYDROLOGY INFORMATION AT NODE<<<<< ============================================================================ USER-SPECIFIED VALUES ARE AS FOLLOWS: TC(MIN) = 5.00 RAIN INTENSITY(INCH/HOUR) = 6.61 TOTAL AREA(ACRES) = 0.04 TOTAL RUNOFF(CFS) = 0.22 **************************************************************************** FLOW PROCESS FROM NODE 33.00 TO NODE 33.00 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.) = 5.00 RAINFALL INTENSITY(INCH/HR) = 6.61 TOTAL STREAM AREA(ACRES) = 0.04 PEAK FLOW RATE(CFS) AT CONFLUENCE = 0.22 +--------------------------------------------------------------------------+ | BIOFILTRATION BASIN 2 | | | | | +--------------------------------------------------------------------------+ **************************************************************************** FLOW PROCESS FROM NODE 35.00 TO NODE 35.00 IS CODE = 7 ---------------------------------------------------------------------------- >>>>>USER SPECIFIED HYDROLOGY INFORMATION AT NODE<<<<< ============================================================================ USER-SPECIFIED VALUES ARE AS FOLLOWS: TC(MIN) = 5.00 RAIN INTENSITY(INCH/HOUR) = 6.61 TOTAL AREA(ACRES) = 0.02 TOTAL RUNOFF(CFS) = 0.12 **************************************************************************** FLOW PROCESS FROM NODE 35.00 TO NODE 35.00 IS CODE = 1 ---------------------------------------------------------------------------- >>>>>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE<<<<< >>>>>AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES<<<<< ============================================================================ TOTAL NUMBER OF STREAMS = 3 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 3 ARE: TIME OF CONCENTRATION(MIN.) = 5.00 RAINFALL INTENSITY(INCH/HR) = 6.61 TOTAL STREAM AREA(ACRES) = 0.02 PEAK FLOW RATE(CFS) AT CONFLUENCE = 0.12 ** CONFLUENCE DATA ** Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 19 STREAM RUNOFF Tc INTENSITY AREA NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE) 1 0.82 6.62 5.516 0.24 2 0.22 5.00 6.613 0.04 3 0.12 5.00 6.613 0.02 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 0.96 5.00 6.613 2 0.96 5.00 6.613 3 1.11 6.62 5.516 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE(CFS) = 1.11 Tc(MIN.) = 6.62 TOTAL AREA(ACRES) = 0.3 LONGEST FLOWPATH FROM NODE 10.00 TO NODE 35.00 = 210.00 FEET. ============================================================================ END OF STUDY SUMMARY: TOTAL AREA(ACRES) = 0.3 TC(MIN.) = 6.62 PEAK FLOW RATE(CFS) = 1.11 ============================================================================ ============================================================================ END OF RATIONAL METHOD ANALYSIS Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 20 DETAINED POST-DEVELOPED HYDROLOGY CALCULATIONS Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 21 ____________________________________________________________________________ **************************************************************************** RATIONAL METHOD HYDROLOGY COMPUTER PROGRAM PACKAGE Reference: SAN DIEGO COUNTY FLOOD CONTROL DISTRICT 2003,1985,1981 HYDROLOGY MANUAL (c) Copyright 1982-2014 Advanced Engineering Software (aes) Ver. 21.0 Release Date: 06/01/2014 License ID 1459 Analysis prepared by: BHA INC. 5115 AVENIDA ENCINAS, SUITE L CARLSBAD, CA 92008 ************************** DESCRIPTION OF STUDY ************************** * DETEAINED PROPOSED HYDROLOGY * * * * * ************************************************************************** FILE NAME: K:\HYDRO\1458\1458P1R.DAT TIME/DATE OF STUDY: 09:35 12/01/2020 ---------------------------------------------------------------------------- USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION: ---------------------------------------------------------------------------- 2003 SAN DIEGO MANUAL CRITERIA USER SPECIFIED STORM EVENT(YEAR) = 100.00 6-HOUR DURATION PRECIPITATION (INCHES) = 2.510 SPECIFIED MINIMUM PIPE SIZE(INCH) = 4.00 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 30.0 20.0 0.018/0.018/0.020 0.67 2.00 0.0313 0.167 0.0150 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.* **************************************************************************** FLOW PROCESS FROM NODE 10.00 TO NODE 20.00 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< ============================================================================ *USER SPECIFIED(SUBAREA): USER-SPECIFIED RUNOFF COEFFICIENT = .7200 S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET) = 70.00 UPSTREAM ELEVATION(FEET) = 59.90 DOWNSTREAM ELEVATION(FEET) = 59.20 ELEVATION DIFFERENCE(FEET) = 0.70 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 22 SUBAREA OVERLAND TIME OF FLOW(MIN.) = 5.723 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.062 SUBAREA RUNOFF(CFS) = 0.35 TOTAL AREA(ACRES) = 0.08 TOTAL RUNOFF(CFS) = 0.35 **************************************************************************** FLOW PROCESS FROM NODE 20.00 TO NODE 30.00 IS CODE = 51 ---------------------------------------------------------------------------- >>>>>COMPUTE TRAPEZOIDAL CHANNEL FLOW<<<<< >>>>>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 59.20 DOWNSTREAM(FEET) = 58.10 CHANNEL LENGTH THRU SUBAREA(FEET) = 35.00 CHANNEL SLOPE = 0.0314 CHANNEL BASE(FEET) = 0.00 "Z" FACTOR = 20.000 MANNING'S FACTOR = 0.030 MAXIMUM DEPTH(FEET) = 0.50 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.792 *USER SPECIFIED(SUBAREA): USER-SPECIFIED RUNOFF COEFFICIENT = .5000 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 0.43 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) = 1.39 AVERAGE FLOW DEPTH(FEET) = 0.12 TRAVEL TIME(MIN.) = 0.42 Tc(MIN.) = 6.14 SUBAREA AREA(ACRES) = 0.06 SUBAREA RUNOFF(CFS) = 0.16 AREA-AVERAGE RUNOFF COEFFICIENT = 0.630 TOTAL AREA(ACRES) = 0.1 PEAK FLOW RATE(CFS) = 0.50 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH(FEET) = 0.13 FLOW VELOCITY(FEET/SEC.) = 1.42 LONGEST FLOWPATH FROM NODE 10.00 TO NODE 30.00 = 105.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 30.00 TO NODE 40.00 IS CODE = 51 ---------------------------------------------------------------------------- >>>>>COMPUTE TRAPEZOIDAL CHANNEL FLOW<<<<< >>>>>TRAVELTIME THRU SUBAREA (EXISTING ELEMENT)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 58.10 DOWNSTREAM(FEET) = 52.90 CHANNEL LENGTH THRU SUBAREA(FEET) = 105.00 CHANNEL SLOPE = 0.0495 CHANNEL BASE(FEET) = 0.00 "Z" FACTOR = 20.000 MANNING'S FACTOR = 0.013 MAXIMUM DEPTH(FEET) = 0.50 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.516 *USER SPECIFIED(SUBAREA): USER-SPECIFIED RUNOFF COEFFICIENT = .5900 S.C.S. CURVE NUMBER (AMC II) = 0 TRAVEL TIME COMPUTED USING ESTIMATED FLOW(CFS) = 0.67 TRAVEL TIME THRU SUBAREA BASED ON VELOCITY(FEET/SEC.) = 3.63 AVERAGE FLOW DEPTH(FEET) = 0.10 TRAVEL TIME(MIN.) = 0.48 Tc(MIN.) = 6.62 SUBAREA AREA(ACRES) = 0.11 SUBAREA RUNOFF(CFS) = 0.35 AREA-AVERAGE RUNOFF COEFFICIENT = 0.613 TOTAL AREA(ACRES) = 0.2 PEAK FLOW RATE(CFS) = 0.82 END OF SUBAREA CHANNEL FLOW HYDRAULICS: DEPTH(FEET) = 0.11 FLOW VELOCITY(FEET/SEC.) = 3.43 LONGEST FLOWPATH FROM NODE 10.00 TO NODE 40.00 = 210.00 FEET. **************************************************************************** FLOW PROCESS FROM NODE 40.00 TO NODE 40.00 IS CODE = 1 ---------------------------------------------------------------------------- >>>>>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE<<<<< ============================================================================ Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 23 TOTAL NUMBER OF STREAMS = 3 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 1 ARE: TIME OF CONCENTRATION(MIN.) = 6.62 RAINFALL INTENSITY(INCH/HR) = 5.52 TOTAL STREAM AREA(ACRES) = 0.24 PEAK FLOW RATE(CFS) AT CONFLUENCE = 0.82 +--------------------------------------------------------------------------+ | BIOFILTRATION BASIN 1 | | | | | +--------------------------------------------------------------------------+ **************************************************************************** FLOW PROCESS FROM NODE 33.00 TO NODE 33.00 IS CODE = 7 ---------------------------------------------------------------------------- >>>>>USER SPECIFIED HYDROLOGY INFORMATION AT NODE<<<<< ============================================================================ USER-SPECIFIED VALUES ARE AS FOLLOWS: TC(MIN) = 15.00 RAIN INTENSITY(INCH/HOUR) = 3.26 TOTAL AREA(ACRES) = 0.04 TOTAL RUNOFF(CFS) = 0.04 **************************************************************************** FLOW PROCESS FROM NODE 33.00 TO NODE 33.00 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.) = 15.00 RAINFALL INTENSITY(INCH/HR) = 3.26 TOTAL STREAM AREA(ACRES) = 0.04 PEAK FLOW RATE(CFS) AT CONFLUENCE = 0.04 +--------------------------------------------------------------------------+ | BIOFILTRATION BASIN 2 | | | | | +--------------------------------------------------------------------------+ **************************************************************************** FLOW PROCESS FROM NODE 35.00 TO NODE 35.00 IS CODE = 7 ---------------------------------------------------------------------------- >>>>>USER SPECIFIED HYDROLOGY INFORMATION AT NODE<<<<< ============================================================================ USER-SPECIFIED VALUES ARE AS FOLLOWS: TC(MIN) = 15.00 RAIN INTENSITY(INCH/HOUR) = 3.26 TOTAL AREA(ACRES) = 0.02 TOTAL RUNOFF(CFS) = 0.01 **************************************************************************** FLOW PROCESS FROM NODE 35.00 TO NODE 35.00 IS CODE = 1 ---------------------------------------------------------------------------- >>>>>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE<<<<< >>>>>AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES<<<<< ============================================================================ TOTAL NUMBER OF STREAMS = 3 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 3 ARE: TIME OF CONCENTRATION(MIN.) = 15.00 RAINFALL INTENSITY(INCH/HR) = 3.26 TOTAL STREAM AREA(ACRES) = 0.02 PEAK FLOW RATE(CFS) AT CONFLUENCE = 0.01 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 24 ** CONFLUENCE DATA ** STREAM RUNOFF Tc INTENSITY AREA NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE) 1 0.82 6.62 5.516 0.24 2 0.04 15.00 3.256 0.04 3 0.01 15.00 3.256 0.02 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 0.85 6.62 5.516 2 0.54 15.00 3.256 3 0.54 15.00 3.256 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE(CFS) = 0.85 Tc(MIN.) = 6.62 TOTAL AREA(ACRES) = 0.3 LONGEST FLOWPATH FROM NODE 10.00 TO NODE 35.00 = 210.00 FEET. ============================================================================ END OF STUDY SUMMARY: TOTAL AREA(ACRES) = 0.3 TC(MIN.) = 6.62 PEAK FLOW RATE(CFS) = 0.85 ============================================================================ ============================================================================ END OF RATIONAL METHOD ANALYSIS Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 25 6-INCH AND 8-INCH PIPE CALCULATIONS ____________________________________________________________________________ Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 26 **************************************************************************** HYDRAULIC ELEMENTS - I PROGRAM PACKAGE (C) Copyright 1982-2014 Advanced Engineering Software (aes) Ver. 21.0 Release Date: 06/01/2014 License ID 1459 Analysis prepared by: BHA INC. 5115 AVENIDA ENCINAS, SUITE L CARLSBAD, CA 92008 ---------------------------------------------------------------------------- TIME/DATE OF STUDY: 12:10 05/03/2020 ============================================================================ Problem Descriptions: 6-inch Pipe Flow @ 1.0% **************************************************************************** >>>>PIPEFLOW HYDRAULIC INPUT INFORMATION<<<< ---------------------------------------------------------------------------- PIPE DIAMETER(FEET) = 0.500 FLOWDEPTH(FEET) = 0.450 PIPE SLOPE(FEET/FEET) = 0.0100 MANNINGS FRICTION FACTOR = 0.013000 >>>>> NORMAL DEPTH FLOW(CFS) = 0.60 ============================================================================ NORMAL-DEPTH FLOW INFORMATION: ---------------------------------------------------------------------------- NORMAL DEPTH(FEET) = 0.45 FLOW AREA(SQUARE FEET) = 0.19 FLOW TOP-WIDTH(FEET) = 0.300 FLOW PRESSURE + MOMENTUM(POUNDS) = 3.72 FLOW VELOCITY(FEET/SEC.) = 3.213 FLOW VELOCITY HEAD(FEET) = 0.160 HYDRAULIC DEPTH(FEET) = 0.62 FROUDE NUMBER = 0.719 SPECIFIC ENERGY(FEET) = 0.61 ============================================================================ ____________________________________________________________________________ Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 27 **************************************************************************** HYDRAULIC ELEMENTS - I PROGRAM PACKAGE (C) Copyright 1982-2014 Advanced Engineering Software (aes) Ver. 21.0 Release Date: 06/01/2014 License ID 1459 Analysis prepared by: BHA INC. 5115 AVENIDA ENCINAS, SUITE L CARLSBAD, CA 92008 ---------------------------------------------------------------------------- TIME/DATE OF STUDY: 11:26 05/03/2020 ============================================================================ Problem Descriptions: 8-inch Pipe Flow @ 1.0% **************************************************************************** >>>>PIPEFLOW HYDRAULIC INPUT INFORMATION<<<< ---------------------------------------------------------------------------- PIPE DIAMETER(FEET) = 0.670 PIPE SLOPE(FEET/FEET) = 0.0100 PIPEFLOW(CFS) = 1.11 MANNINGS FRICTION FACTOR = 0.013000 ============================================================================ CRITICAL-DEPTH FLOW INFORMATION: ---------------------------------------------------------------------------- CRITICAL DEPTH(FEET) = 0.50 CRITICAL FLOW AREA(SQUARE FEET) = 0.282 CRITICAL FLOW TOP-WIDTH(FEET) = 0.584 CRITICAL FLOW PRESSURE + MOMENTUM(POUNDS) = 8.48 CRITICAL FLOW VELOCITY(FEET/SEC.) = 3.941 CRITICAL FLOW VELOCITY HEAD(FEET) = 0.24 CRITICAL FLOW HYDRAULIC DEPTH(FEET) = 0.48 CRITICAL FLOW SPECIFIC ENERGY(FEET) = 0.74 ============================================================================ NORMAL-DEPTH FLOW INFORMATION: ---------------------------------------------------------------------------- NORMAL DEPTH(FEET) = 0.50 FLOW AREA(SQUARE FEET) = 0.28 FLOW TOP-WIDTH(FEET) = 0.583 FLOW PRESSURE + MOMENTUM(POUNDS) = 8.46 FLOW VELOCITY(FEET/SEC.) = 3.934 FLOW VELOCITY HEAD(FEET) = 0.240 HYDRAULIC DEPTH(FEET) = 0.48 FROUDE NUMBER = 0.997 SPECIFIC ENERGY(FEET) = 0.74 ============================================================================ Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 28 III. HYDRAULIC CALCULATIONS BASIN OUTLET DETAILS Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 29 BASIN OUTLET DETAILS 8U/UJING rn.HJA TKM BUIWING rn.HJATKM BW FOOTPRINT " 57.16 FG SPI.ASH PNJ "l'ERF'MAlED P\C PfPE P\C PF£ !Un£-lolk ONC SZE LARGER »£ Pff DIA JO 1,11. llll'ERIENU utER--J RUNNING IMI.L BIOFD.TRATION BASIN 2 SECTION D-D N.T.S. EIIP FOOTPRINT 57.89 F, SPI.ASH PNJ --_______________ g --------- BIOFILTRATION BASIN 1 SECTION B-B N.T.S. 58.55 TW -J RITIJHIHG IMI.L 'JO MIL UNER N01E:; JO-MIL IMPERMEA81£ UNER FOR 8I0RE1E:NllOI/ CONFORM TO THE' FOLLOMNG SPE'C/F1CAT!ONS, SPECIFIC GRAWTY (ASIM D792): 1.2 (G/CC. MIN.): 1E:NSJI£ (AS1M D882): 7J (LB/IN-MDTH. MIN): ELOI/GAT!ON AT BREAK (AS11.1 0882): J80 (:t MIN); MODULUS (AS1M 0882): JO (LB/IN-MOTH. MIN.): ANO 1E:AR STRENGTH (ASIM 01004): 8 (LB/IN. MIN): SEAM SHEAR STRENGTH (AS1M D882) 58.4 (LB/IN, MIN); SEAM PEEL STRENGTH (AS1M D882) 15 (LB/IN, IN). SEE COLORADO LINING INTERNAT!ONAL PVC JO HTTP· (/WWNCOI QRAQOI/NING CQM/1>ROQIJCTSIPVCPD[I OR APPROvrn E'OUAL. Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 30 STORAGE AND CAPACITY CALCULATIONS AND 85th PERCENTILE VOLUMES Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 31 Stage‐Storage & Stage‐Discharge Relationship for Biofiltration Basin 1 Discharge vs. Elevation Table HMP orifice Basin Dimensions No. of orif: 1 Area: 104 ft2 Gravel Porosity 0.4 Dia: 6.00 in Perimeter 44 ft Soil Porositiy 0.2 Area: 0.1963 ft2 Gravel Depth 1.00 ft Cg‐low: 0.62 Soil Depth 1.50 ft Mulch Depth 0.25 ft Total Subsurface Depth 2.75 ft Basin Depth Volume Basin Depth Volume Qtotal (ft)(ft3)(ft) (acre‐ft) (cfs) 0.000 0 0.000 0.00000 0.0000 0.083 6 0.083 0.00015 0.0120 0.167 10 0.167 0.00023 0.0120 0.250 13 0.250 0.00031 0.0120 0.333 17 0.333 0.00039 0.0120 0.417 20 0.417 0.00047 0.0120 0.500 24 0.500 0.00055 0.0120 0.583 27 0.583 0.00063 0.0120 0.667 31 0.667 0.00071 0.0120 0.750 34 0.750 0.00079 0.0120 0.833 38 0.833 0.00086 0.0120 0.917 41 0.917 0.00094 0.0120 1.000 45 1.000 0.00102 0.0120 1.083 46 1.083 0.00106 0.0120 1.167 48 1.167 0.00110 0.0120 1.250 50 1.250 0.00114 0.0120 1.333 52 1.333 0.00118 0.0120 1.417 53 1.417 0.00122 0.0120 1.500 55 1.500 0.00126 0.0120 1.583 57 1.583 0.00130 0.0120 1.667 58 1.667 0.00134 0.0120 1.750 60 1.750 0.00138 0.0120 1.833 62 1.833 0.00142 0.0120 1.917 64 1.917 0.00146 0.0120 2.000 65 2.000 0.00150 0.0120 2.083 67 2.083 0.00154 0.0120 2.167 69 2.167 0.00158 0.0120 2.250 71 2.250 0.00162 0.0120 2.333 72 2.333 0.00166 0.0120 2.417 74 2.417 0.00170 0.0120 2.500 76 2.500 0.00174 0.0120 2.583 78 2.583 0.00178 0.0120 2.667 79 2.667 0.00182 0.0120 2.750 0.0000 57.16 81 2.750 0.00186 0.0120 2.833 0.0833 57.24 90 2.833 0.00206 0.0120 2.917 0.1667 57.33 98 2.917 0.00226 0.0120 3.000 0.2500 57.41 107 3.000 0.00246 0.0120 3.083 0.3333 57.49 116 3.083 0.00266 0.0120 3.167 0.4167 57.58 124 3.167 0.00285 0.0120 3.250 0.5000 57.66 133 3.250 0.00305 0.6086 3.333 0.5833 57.74 142 3.333 0.00325 1.6995 3.417 0.6667 57.83 150 3.417 0.00345 3.1120 3.500 0.7500 57.91 159 3.500 0.00365 4.7848 Basin Elev.Ponding Depth Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 32 Stage‐Storage & Stage‐Discharge Relationship for Biofiltration Basin 2 Discharge vs. Elevation Table HMP orifice Basin Dimensions No. of orif: 1 Area: 59 ft2 Gravel Porosity 0.4 Dia: 6.00 in Perimeter 44 ft Soil Porositiy 0.2 Area: 0.1963 ft2 Gravel Depth 1.00 ft Cg‐low: 0.62 Soil Depth 1.50 ft Mulch Depth 0.25 ft Total Subsurface Depth 2.75 ft Basin Depth Volume Basin Depth Volume Qtotal (ft)(ft3)(ft) (acre‐ft) (cfs) 0.000 0 0.000 0.00000 0.0000 0.083 5 0.083 0.00011 0.0068 0.167 7 0.167 0.00016 0.0068 0.250 9 0.250 0.00020 0.0068 0.333 11 0.333 0.00025 0.0068 0.417 13 0.417 0.00029 0.0068 0.500 15 0.500 0.00034 0.0068 0.583 17 0.583 0.00038 0.0068 0.667 19 0.667 0.00043 0.0068 0.750 21 0.750 0.00048 0.0068 0.833 23 0.833 0.00052 0.0068 0.917 25 0.917 0.00057 0.0068 1.000 27 1.000 0.00061 0.0068 1.083 28 1.083 0.00063 0.0068 1.167 29 1.167 0.00066 0.0068 1.250 30 1.250 0.00068 0.0068 1.333 31 1.333 0.00070 0.0068 1.417 32 1.417 0.00072 0.0068 1.500 33 1.500 0.00075 0.0068 1.583 33 1.583 0.00077 0.0068 1.667 34 1.667 0.00079 0.0068 1.750 35 1.750 0.00081 0.0068 1.833 36 1.833 0.00084 0.0068 1.917 37 1.917 0.00086 0.0068 2.000 38 2.000 0.00088 0.0068 2.083 39 2.083 0.00090 0.0068 2.167 40 2.167 0.00093 0.0068 2.250 41 2.250 0.00095 0.0068 2.333 42 2.333 0.00097 0.0068 2.417 43 2.417 0.00099 0.0068 2.500 44 2.500 0.00102 0.0068 2.583 45 2.583 0.00104 0.0068 2.667 46 2.667 0.00106 0.0068 2.750 0.0000 57.89 47 2.750 0.00108 0.0068 2.833 0.0833 57.97 52 2.833 0.00120 0.0068 2.917 0.1667 58.06 57 2.917 0.00131 0.0068 3.000 0.2500 58.14 62 3.000 0.00142 0.0068 3.083 0.3333 58.22 67 3.083 0.00154 0.0116 3.167 0.4167 58.31 72 3.167 0.00165 0.6396 3.250 0.5000 58.39 77 3.250 0.00176 1.7451 3.333 0.5833 58.47 82 3.333 0.00187 3.1690 3.417 0.6667 58.56 87 3.417 0.00199 4.8514 Basin Elev.Ponding Depth Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 33 STORAGE BASIN HYDROGRAPH - BIOFILTRATION BASIN 1 Q100yr = 0.22 Tc = 5 min P6 100yr = 2.51 in C = 0.87 A = 0.038 I =7.44*P6*D‐0.645 6.61319 VOL =I*D/60 ∆VOL =V1 ‐V0 I (incr) = ∆VOL/T Q =CIA VOL = C*P6 *A ND I VOL ∆VOL I (incr) Q VOL (min)(in/hr)in (in)(in\hr)(cfs)(cf) 0 0 0 0 0.55 6.61 0.2203 66 0.0000 1 5 6.61 0.55 0.15 1.84 0.0615 18 0.0050 2 10 4.23 0.70 0.11 1.31 0.0436 13 0.0050 3 15 3.26 0.81 0.09 1.05 0.0350 10 0.0051 4 20 2.70 0.90 0.07 0.89 0.0297 9 0.0052 5 25 2.34 0.98 0.07 0.78 0.0261 8 0.0053 6 30 2.08 1.04 0.06 0.70 0.0234 7 0.0053 7 35 1.89 1.10 0.05 0.64 0.0213 6 0.0054 8 40 1.73 1.15 0.05 0.59 0.0197 6 0.0055 9 45 1.60 1.20 0.05 0.55 0.0183 5 0.0056 10 50 1.50 1.25 0.04 0.52 0.0172 5 0.0057 11 55 1.41 1.29 0.04 0.49 0.0162 5 0.0058 12 60 1.33 1.33 0.04 0.46 0.0153 5 0.0059 13 65 1.26 1.37 0.04 0.44 0.0146 4 0.0060 14 70 1.21 1.41 0.03 0.42 0.0139 4 0.0061 15 75 1.15 1.44 0.03 0.40 0.0134 4 0.0062 16 80 1.11 1.47 0.03 0.38 0.0128 4 0.0063 17 85 1.06 1.51 0.03 0.37 0.0123 4 0.0065 18 90 1.03 1.54 0.03 0.36 0.0119 4 0.0066 19 95 0.99 1.57 0.03 0.35 0.0115 3 0.0068 20 100 0.96 1.60 0.03 0.33 0.0111 3 0.0069 21 105 0.93 1.62 0.03 0.32 0.0108 3 0.0071 22 110 0.90 1.65 0.03 0.32 0.0105 3 0.0072 23 115 0.88 1.68 0.03 0.31 0.0102 3 0.0074 24 120 0.85 1.70 0.02 0.30 0.0099 3 0.0076 25 125 0.83 1.73 0.02 0.29 0.0097 3 0.0078 26 130 0.81 1.75 0.02 0.28 0.0094 3 0.0080 (Re‐0rdered) Ordinate Sum = Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 34 27 135 0.79 1.78 0.02 0.28 0.0092 3 0.0083 28 140 0.77 1.80 0.02 0.27 0.0090 3 0.0085 29 145 0.75 1.82 0.02 0.26 0.0088 3 0.0088 30 150 0.74 1.84 0.02 0.26 0.0086 3 0.0090 31 155 0.72 1.86 0.02 0.25 0.0085 3 0.0094 32 160 0.71 1.89 0.02 0.25 0.0083 2 0.0097 33 165 0.69 1.91 0.02 0.24 0.0081 2 0.0102 34 170 0.68 1.93 0.02 0.24 0.0080 2 0.0105 35 175 0.67 1.95 0.02 0.23 0.0078 2 0.0111 36 180 0.66 1.97 0.02 0.23 0.0077 2 0.0115 37 185 0.64 1.99 0.02 0.23 0.0076 2 0.0123 38 190 0.63 2.00 0.02 0.22 0.0074 2 0.0128 39 195 0.62 2.02 0.02 0.22 0.0073 2 0.0139 40 200 0.61 2.04 0.02 0.22 0.0072 2 0.0146 41 205 0.60 2.06 0.02 0.21 0.0071 2 0.0162 42 210 0.59 2.08 0.02 0.21 0.0070 2 0.0172 43 215 0.58 2.09 0.02 0.21 0.0069 2 0.0197 44 220 0.58 2.11 0.02 0.20 0.0068 2 0.0213 45 225 0.57 2.13 0.02 0.20 0.0067 2 0.0261 46 230 0.56 2.15 0.02 0.20 0.0066 2 0.0297 47 235 0.55 2.16 0.02 0.19 0.0065 2 0.0436 48 240 0.54 2.18 0.02 0.19 0.0064 2 0.0615 49 245 0.54 2.19 0.02 0.19 0.0063 2 0.2203 50 250 0.53 2.21 0.02 0.19 0.0062 2 0.0350 51 255 0.52 2.23 0.02 0.18 0.0062 2 0.0234 52 260 0.52 2.24 0.02 0.18 0.0061 2 0.0183 53 265 0.51 2.26 0.02 0.18 0.0060 2 0.0153 54 270 0.50 2.27 0.01 0.18 0.0059 2 0.0134 55 275 0.50 2.29 0.01 0.18 0.0059 2 0.0119 56 280 0.49 2.30 0.01 0.17 0.0058 2 0.0108 57 285 0.49 2.32 0.01 0.17 0.0057 2 0.0099 58 290 0.48 2.33 0.01 0.17 0.0057 2 0.0092 59 295 0.48 2.34 0.01 0.17 0.0056 2 0.0086 60 300 0.47 2.36 0.01 0.17 0.0055 2 0.0081 61 305 0.47 2.37 0.01 0.16 0.0055 2 0.0077 62 310 0.46 2.39 0.01 0.16 0.0054 2 0.0073 63 315 0.46 2.40 0.01 0.16 0.0054 2 0.0070 64 320 0.45 2.41 0.01 0.16 0.0053 2 0.0067 65 325 0.45 2.43 0.01 0.16 0.0053 2 0.0064 66 330 0.44 2.44 0.01 0.16 0.0052 2 0.0062 67 335 0.44 2.45 0.01 0.16 0.0052 2 0.0059 68 340 0.43 2.46 0.01 0.15 0.0051 2 0.0057 69 345 0.43 2.48 0.01 0.15 0.0051 2 0.0055 70 350 0.43 2.49 0.01 0.15 0.0050 2 0.0054 71 355 0.42 2.50 0.01 0.15 0.0050 1 0.0052 72 360 0.42 2.52 0.00 0.00 0.0000 0 0.0000 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 35 BIOFILTRATION BASIN 1 Initial Storage Runoff Coefficeint = 0.87 85th Percentile Rainfall (I) (in) = 0.57 Area = 0.038 Initial Storage = CIA = 0.00158 i l l Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 36 STORAGE BASIN HYDROGRAPH - BIOFILTRATION BASIN 2 Q100yr = 0.12 Tc = 5 min P6 100yr = 2.51 in C = 0.87 A = 0.021 I =7.44*P6*D‐0.645 6.61319 VOL = I*D/60 ∆VOL = V1 ‐V0 I (incr) = ∆VOL/T Q = CIA VOL = C*P6 *A ND I VOL ∆VOL I (incr) Q VOL (min) (in/hr) in (in) (in\hr) (cfs) (cf) 0 0 0 0 0.55 6.61 0.1197 36 0.0000 1 5 6.61 0.55 0.15 1.84 0.0334 10 0.0027 2 10 4.23 0.70 0.11 1.31 0.0237 7 0.0027 3 15 3.26 0.81 0.09 1.05 0.0190 6 0.0028 4 20 2.70 0.90 0.07 0.89 0.0161 5 0.0028 5 25 2.34 0.98 0.07 0.78 0.0142 4 0.0029 6 30 2.08 1.04 0.06 0.70 0.0127 4 0.0029 7 35 1.89 1.10 0.05 0.64 0.0116 3 0.0030 8 40 1.73 1.15 0.05 0.59 0.0107 3 0.0030 9 45 1.60 1.20 0.05 0.55 0.0099 3 0.0030 10 50 1.50 1.25 0.04 0.52 0.0093 3 0.0031 11 55 1.41 1.29 0.04 0.49 0.0088 3 0.0031 12 60 1.33 1.33 0.04 0.46 0.0083 2 0.0032 13 65 1.26 1.37 0.04 0.44 0.0079 2 0.0033 14 70 1.21 1.41 0.03 0.42 0.0076 2 0.0033 15 75 1.15 1.44 0.03 0.40 0.0073 2 0.0034 16 80 1.11 1.47 0.03 0.38 0.0070 2 0.0034 17 85 1.06 1.51 0.03 0.37 0.0067 2 0.0035 18 90 1.03 1.54 0.03 0.36 0.0065 2 0.0036 19 95 0.99 1.57 0.03 0.35 0.0063 2 0.0037 20 100 0.96 1.60 0.03 0.33 0.0061 2 0.0037 21 105 0.93 1.62 0.03 0.32 0.0059 2 0.0038 22 110 0.90 1.65 0.03 0.32 0.0057 2 0.0039 23 115 0.88 1.68 0.03 0.31 0.0055 2 0.0040 24 120 0.85 1.70 0.02 0.30 0.0054 2 0.0041 25 125 0.83 1.73 0.02 0.29 0.0053 2 0.0042 26 130 0.81 1.75 0.02 0.28 0.0051 2 0.0043 (Re‐0rdered) Ordinate Sum = Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 37 27 135 0.79 1.78 0.02 0.28 0.0050 2 0.0045 28 140 0.77 1.80 0.02 0.27 0.0049 1 0.0046 29 145 0.75 1.82 0.02 0.26 0.0048 1 0.0048 30 150 0.74 1.84 0.02 0.26 0.0047 1 0.0049 31 155 0.72 1.86 0.02 0.25 0.0046 1 0.0051 32 160 0.71 1.89 0.02 0.25 0.0045 1 0.0053 33 165 0.69 1.91 0.02 0.24 0.0044 1 0.0055 34 170 0.68 1.93 0.02 0.24 0.0043 1 0.0057 35 175 0.67 1.95 0.02 0.23 0.0042 1 0.0061 36 180 0.66 1.97 0.02 0.23 0.0042 1 0.0063 37 185 0.64 1.99 0.02 0.23 0.0041 1 0.0067 38 190 0.63 2.00 0.02 0.22 0.0040 1 0.0070 39 195 0.62 2.02 0.02 0.22 0.0040 1 0.0076 40 200 0.61 2.04 0.02 0.22 0.0039 1 0.0079 41 205 0.60 2.06 0.02 0.21 0.0038 1 0.0088 42 210 0.59 2.08 0.02 0.21 0.0038 1 0.0093 43 215 0.58 2.09 0.02 0.21 0.0037 1 0.0107 44 220 0.58 2.11 0.02 0.20 0.0037 1 0.0116 45 225 0.57 2.13 0.02 0.20 0.0036 1 0.0142 46 230 0.56 2.15 0.02 0.20 0.0036 1 0.0161 47 235 0.55 2.16 0.02 0.19 0.0035 1 0.0237 48 240 0.54 2.18 0.02 0.19 0.0035 1 0.0334 49 245 0.54 2.19 0.02 0.19 0.0034 1 0.1197 50 250 0.53 2.21 0.02 0.19 0.0034 1 0.0190 51 255 0.52 2.23 0.02 0.18 0.0033 1 0.0127 52 260 0.52 2.24 0.02 0.18 0.0033 1 0.0099 53 265 0.51 2.26 0.02 0.18 0.0033 1 0.0083 54 270 0.50 2.27 0.01 0.18 0.0032 1 0.0073 55 275 0.50 2.29 0.01 0.18 0.0032 1 0.0065 56 280 0.49 2.30 0.01 0.17 0.0031 1 0.0059 57 285 0.49 2.32 0.01 0.17 0.0031 1 0.0054 58 290 0.48 2.33 0.01 0.17 0.0031 1 0.0050 59 295 0.48 2.34 0.01 0.17 0.0030 1 0.0047 60 300 0.47 2.36 0.01 0.17 0.0030 1 0.0044 61 305 0.47 2.37 0.01 0.16 0.0030 1 0.0042 62 310 0.46 2.39 0.01 0.16 0.0030 1 0.0040 63 315 0.46 2.40 0.01 0.16 0.0029 1 0.0038 64 320 0.45 2.41 0.01 0.16 0.0029 1 0.0036 65 325 0.45 2.43 0.01 0.16 0.0029 1 0.0035 66 330 0.44 2.44 0.01 0.16 0.0028 1 0.0033 67 335 0.44 2.45 0.01 0.16 0.0028 1 0.0032 68 340 0.43 2.46 0.01 0.15 0.0028 1 0.0031 69 345 0.43 2.48 0.01 0.15 0.0028 1 0.0030 70 350 0.43 2.49 0.01 0.15 0.0027 1 0.0029 71 355 0.42 2.50 0.01 0.15 0.0027 1 0.0028 72 360 0.42 2.52 0.00 0.00 0.0000 0 0.0000 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 38 BIOFILTRATION BASIN 2 Initial Storage Runoff Coefficeint = 0.87 85th Percentile Rainfall (I) (in) = 0.57 Area = 0.021 Initial Storage = CIA = 0.00086 i l l Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 39 STORAGE BASIN HYDROGRAPH ROUTING MODELS Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 40 BIOFILTRATION BASIN 1 11/30(2020 Project: Raised Planter Simulation Run: Qroo Standard Report Simulation Start: 31 December 1999, 24:00 Simulation End: I January 2000, 06:00 HMS Version: 4.6.1 Executed: 01 December 2020, 00:30 Global Results Summary Hydrologic Element Drainage Area (Mb) Peak Discharge (CFS) Dma I Not specified 0.2.2. Basin 1 Not specified 0.04 1'°11DeofPeak 01Jan2.ooo, 04,05 01Jan2000, 04:15 fle://Jl<.:/CMI 3D/1458/REP0RTS/HYDROL0GY,1-!EC-HM$/PDF$.-RAl$ED PLANTER 1/RAISED PLANTER 1.html Volume(IN) N/a N/a 1/5 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 41 11/30/2020 Source: DMA I Downstream : Basin I Flow Method: Gage Flow Flow Gage : POC -I Peak Discharge (CFS) Time of Peak Discharge Volume(IN) 0.15 ,ii' "' ~ ~ 0.1 "' 0.05 0 00:00 01:00 Jan1,2000 oz,oo Staridard Report Reault1:DMA1 Outflow Tune 0.22 01Jan2000, 04:05 Not specified 04,00 fieJ//K:ICMI 3D/1458/REPORTSIHYDROLOOYA-iEC-HMS/PDFSIRAISED PLANTER 1/RAISED PLANfER 1.hlml 06:00 2/5 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 42 11/30/2020 Reservoir: Basin I Peak Discharge (CFS) Time of Peak Discharge Volume(IN) Peak Inflow (CFS) Time of Peak Inflow Inflow Volume (AC -FT) Maximum Storage (AC -FT) Peak Elevation (FT) Discharge Volume (AC -FT) Observed Pool Elevation Gage Observed Peak Pool Elevation (FT) Observed Pool Elevation RMSE Stdev Observed Pool Elevation Percent Bias Time of Maximum Observed Pool Elevation Observed Pool Elevation Nash Sutcliffe Standard Report Results: Buin I 0.04 01Jan2000, 04:15 Not specified 0.22 01Jan2000, 04:05 0.01 0 3.17 0.01 Not specified Not specified Not specified Not specified Not specified Not specified fiei//K'./Civil 3D/1458/REPORTS/HYDR0L0GYIHEC-HM$/PDF$/RAl$ED PLANTER 1/RAISED PLANTER 1.hlml Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 43 11/30/2020 0.003 0.002s f 0.002 i ~ ~O,OOIS 0 !ii 0.001 o.ooos en ~ ii, ~ g; ~ ~ 8 t g ~ 00:00 Jan 1, 2000 0.2 0.15 0.1 o.os 0 00;()0 Jan1,2000 Standard Report Storage 01:00 02:00 03=00 Tune Combined Inflow 01,00 02;00 03,00 O.j.;00 Tune fie'///K:/CMI 3D/14~P0RTS/HYDR0L0GY/I-IEC-HMS/PDFSIRAISED PLANTER 1/RAISED PLANTER 1.html 06:00 05,00 06;00 4/5 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 44 11 /30/'l020 t: z 0 ~ ~ Ill 3 "·S 2 1.5 0.5 00:00 Ja.o 1,2000 0.04 0.035 0.02 0.01s 00:00 Jan1,2000 Standard Report Pool Elevation 01:00 0!2:00 03:00 04:00 Time Outflow 01:00 02:00 04:00 Time fie:///K:/Civll 3D/1458/REPORTS/HYDROLOGY/I-IEC-HMS/PDFSIRAISED PLANTER 1/RAISED PLANTER 1.html os:oo 06:00 05:00 06:00 5/5 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 45 BIOFILTRATION BASIN 2 11/30f.!020 Project: Raised Planter 2 Simulation Run: Qroo Standard Report Simulation Start: 31 December 1999, 24:00 Simulation End: I January 2000, 06:00 HMS Version: 4.6.1 Executed: 01 December 2020, 00:26 Global Results Summary Hydrolc,sic Element Drainage Area (Mla) Peak Discharge (CPS) Dma1 Basin I Not specified Not specified 0.12 0.01 T"uneofPealr. 01Jan2000, 04:os 01Jan2000, 04:15 He:///K:/CMI 3D/1458/REPORTS/HYDROLOOY/HEC-HMS/PDFS/RAISED Pl.ANTER 2/RAISED PLANTER 2.html Volume(IN) N/a Nia 1/5 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 46 11(30/2020 Source: DMA I Downstream: Basin I Flow Method: Gage Flow Flow Gage : POC -I Peak Discharge (CFS) Time of Peak Discharge Volume(IN) 0.12 0.1 o.08 -;;;- "' ~ ~ o.o6 "' 0.04 0.02 0 00:00 01:00 Janl,2000 02:00 Standard Report Reaulta: DMA I Outflow Time 0.12 01Jan2000, 04:05 Not specified 04:00 fieJI/KJClvH 30(1458/REPORTSIHYDROLOGY/HEC-HMS/PDFS/RAISED PLANTER z.RAISED PL.ANTER 2.html 06:oo Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 47 11/30/2020 Reservoir: Basin I Peak Discharge (CFS) Time of Peak Discharge Volume(IN) Peak Inflow (CFS) Time of Peak Inflow Inflow Volume (AC -FT) Maximum Storage (AC -FT) Peak Elevation (FT) Discharge Volume (AC -FT) Observed Pool Elevation Gage Observed Peak Pool Elevation (FT) Observed Pool Elevation RMSE Stdev Observed Pool Elevation Percent Bias Time of Maximum Observed Pool Elevation Observed Pool Elevation Nash Sutcliffe Standard Report Results: Duin I 0.01 01Jan2000, 04:15 Not specified 0.12 01Jan2000, 04:05 0 0 3.08 0 Not specified Not specified Not specified Not specified Not specified Not specified fle:/1/K:/Civil 3D/1458/REPORTSIHYDROLOGY/l-iEC-HMS/PDFS/RAISED PLANTER 2/RAISED PLANTER 2.hlml Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 48 11/30/2020 0.0014 0.0012. f 0,001 i r0008 ~-0006 0.0004 0.0002 .;;- i:z. ~ ~ 25 I'll l 8 ~ g "' 00!00 Janl,2000 0.12 O.l o.o8 o.o6 0,04 0.02. 0 00;00 Jan1,2000 Standard Report Storage 01!00 02!00 o:;:oo Time Combined Inflow 01;00 02;00 OJ.00 Time fiet//K:/Civil 3D/1458/REP0RTSIHYDR0L0GY/HEC-HM$/PDF$/RAl$ED PLANTER 2/RAISED PLANTER 2.html 05:00 06:00 06;00 4/5 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 49 11/30/2020 ~ z 0 ~ ~ ~ 3 2.5 2 1.5 o.s 00!00 Jan1,2000 0.013 o.ou 0.011 o.oo8 01!00 Standard Report Pool Elevation 02!00 o:;:oo 04:00 Time Outflow 0.007 _______________________ _ 00;00 Jan1,2000 01;00 02;00 OJ.00 04,00 Time fiet//K:/Civil 3D/1458/REP0RTSIHYDR0L0GY/HEC-HM$/PDF$/RAl$ED PLANTER 2/RAISED PLANTER 2.html 05:00 06:00 06;00 5/5 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 50 IV. REFERENCES Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 51 Precipitation Frequency Data Server Pagel of 4 NOAA Atlas 14, Volume 6, Version 2 Location name: Carlsbad, California, USA* Latitude: 33.1274', Longitude: -117.3316' Elevation: 63.46 ft** • source: ESRI Maps ... source: USGS POINT PRECIPITATION FREQUENCY ESTIMATES Sanja Perica, Sarah Dietz, Sarah Heim, Lillian Hiner, Kazungu Maitaria, Deborah Martin, Sandra Pavlovic, lshani Roy, Carl Trypaluk, Dale Unruh, Fenglin Yan, Michael Yekta, Tan Zhao, Geoffrey Bonnin, Daniel Brewer, Li-Chuan Chen, Tye Parzybok, John Yarchoan NOAA, National Weather Service, Silver Spring, Maryland PF tabular I PF graphical I Maps & aerials PF tabular I PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches)1 Bl Average recurrence interval (years) I 1 II 2 II 5 II 10 II 25 II 50 II 100 II 200 II 500 II 1000 I 5-min I 0.124 0.156 (0 1~i.g~43)1 0.240 (02~i~1m1I 0.339 0.387 0.438 0.512 0.573 (0.104-0149) (0.131-0.188 0.199-0.291) (0.266-0.437) (0295-0.512) (0.324-0597) (0.363-0. 730) 0391-0848) i 10-min I 0.177 0.224 0.288 0.343 0.422 0.486 0.554 0.628 0.734 0.821 (0.149-0.213) (0.188-0.269 (0.242-0.348) 0.285-0.418) (0.338-0.532) (0.381-0.627) (0.423-0. 733) (0.465-0.856) (0 520-1.05) (0.561-1.22) I 15-min I 0.214 0.271 0.349 0.415 0.510 0.588 0.670 0.759 0.887 0.993 0.180-0.258 0.228-0.326 0.292-0.421 0.345-0.505 0.409-0.644 0.460-0.758 0.511-0.887 I (0.562-104) (0 629-1.26) I (0678-1.47) I30-min I 0.302 0.382 0.491 0.585 0.719 0.828 0.944 1.07 1.25 1.40 (0.254-0.363) (0.321-0.459 (0.411-0.592) 0.486-0. 711) (0.576-0.906) (0.648-1.07) (0. 720-1.25) (0.792-1.46) (0.886-1.78) (0.955-2.07) 60-min 0.411 0.519 0.668 0.795 0.977 1.13 1.28 1.45 1.70 1.90 (0.346-0.493 0.436-0.624 (0 560-0 805) 0.660-0.967 (0. 783-1.23) (0.882-1.45) (0.979-1.70) (108-198) (1.20-2.42) (130-2.81) 2-hr 0.5~6 0.697 0.888 1.05 1.28 1.47 1.66 1.88 2.18 2.43 (0.469-0 .586-0.838 (0.744-1 07) (0.872-1.28) (1.03-1.61) (1.15-189) (1.27-2.20) (139-256) (1.55-3.11) (1 66-3 60) = 3-hr 0.659 0.822 1.05 1.23 1.50 1.71 1.94 2.18 2.52 2.81 (0554-0791 (0.691-0.989 (0875-126) (1.02-1.50) (1.20-1.89) (1.34-2.21) (1.48-2.57) (162-2 97) (1.79-3.60) (1.92-4.15) ~ 0.860 1.08 1.37 1.61 1.95 2.22 2.51 2.80 3.22 3.56 (0. 723-1. 03) (0.904-1.29) (115-1.65) (134-1.96) (1.57-2.46) (174-287) (1.91-332) (208-382) (2.28-4.59) (2.43-526) ~ 1.1 0 1.40 1.79 2.11 2.55 2.89 3.24 3.61 4.12 4.51 (0.926-1.32) (1.17-1.68) (1.50-2.15) (1.75-2.56) (2.04-3.21) (2.27-3.73) (2.48-4.29) (2.68-4.93) (2.92-5.87) (3.08-6.68) ~ 1.35 1.74 2.25 2.66 3.22 3.66 4.10 4.55 5.16 5.64 24-hr (1.19-1.57) (153-2.02) (198-261) (2 32-3.12) (2 72-3.89) (303-450) (3.32-5.16) (359-589) (3.92-6.95) (414-7.85) 2-day 1.65 2.15 2.79 3.31 4.02 4.57 5.13 5.70 6.48 7.08 ~ (1.46-191) (189-2.491 (2.45-3.24) (2.89-3.88) 13.40-4.86) (3.79-5.63) (4.15-6.461 (450-7 38) (4.91-8.72) (5.20-985) I 3-day I 1.86 2.42 3.1 5 3.76 4.58 5.21 5.86 6.53 7.44 8.14 (1.64-2.15) (213-2.80) (2.77-366) (328-4.40) (3.87-5.53) (4.32-6.42) (4.75-7 39) (5.15-8.45) (5.64-100) (598-11.3) 4-day 2.02 2.64 3.45 4.12 5.04 5.75 6.47 7.22 8.24 9.04 (1.78-234) (2 32-3.05) (3.04-4.01) (3.60-4.83) (4.26-6.09) (4 76-7 08) (5.24-8.16) (5 70-934) (6.25-11.1) (663-12.6) 7-day 2.35 3.09 4.08 4.90 6.02 6.90 7.79 8.72 10.0 11.0 (2.07-2.72) (2.73-3.58) (3.59-4.74) (4.27-5.73) (5.09-7.27) (5.71-8.49) (6.31-9.82) (6.88-11.3) (7.58-13.5) (8.08-15.3) = 10-<lay 2.61 3.45 4.59 5.52 6.82 7.83 8.88 9.97 11.5 12.7 (2.30-302) (304-4.00) (4.03-533) (4.81-6.46) (5.76-8.23) (6.49-965) (7.19-11.2) (7 86-129) (8.70-15.4) (9.29-17.6) = 20-<lay 3.15 4.22 5.67 6.89 8.59 9.94 11.3 12.8 14.9 16.5 (2.78-3.64) (3.72-4.89) (499-659) (601-8.06) (7.26-10.4) (8.23-12.2) (9.18-14.3) (101-166) (11.3-20.0) (121-23.0) 130-<lay 1 3.74 5.04 6.81 8.30 10.4 12.1 13.9 15.7 18.4 20.5 (3.30-432) (4.43-5.83) (5.98-7 91) (7.24-9.72) (8.80-12.6) (10.0-149) (11.2-1 7.5) (12.4-20.4) (13.9-24.7) (150-28.5) -4.40 5.94 8.05 9.86 12.4 14.5 16.7 19.0 22.3 25.0 45-<lay (388-509) (5 23-6.88) (7 08-935) (859-115) (105-15.0) (120-17 9) (135-210) (150-246) (16.9-301) (184-34 8) 60-<lay 5.09 6.84 9.28 11.4 14.4 16.8 19.4 22.2 26.2 29.5 (4.49-5.89) (6.03-7.93) (8.15-10.8) (9.92-13.3) (12.2-17.4) (13.9-20.7) (15.7-24.5) (17.5-28.8) ( 19. 9-35. 3) (21.7-41.0) Precipitation frequency (PF) estimates in this table are based on frequency analy~s of partial duration series (PDS). umbers in parenthesis are PF estimates at lc,,,yer and upper bounds of the 90% confidence interval. The probability that precipitation frequency estimates or a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is 5%. Estimates at upper bounds e not checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values to NOAA Atlas 14 document for more information Back to Top I I I https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=33 . l 274&1on=-l l 7J3 l 5&da ... 3/24/2020 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 52 Precipitation Frequency Data Server PF graphical PDS-based depth-duration-frequency (DDF) curves Latitude: 33.1274•, Longitude: -117.3315• 30 ,----,--,----,---,----,---,----,----.----,---.-....,...-,---,---,----,---,---,-, 25 ~ £ 20 C. ., "0 .2 15 -~ C. ·u 10 ~ 5 0 C: ·e J, 30 25 ~ ,:: 20 C. ., "0 C: 15 -~ ·i ·u 10 ~ C. s 01 . ' . ' . . . . . . '-:·. ··~ •• -·~ ••••• , ...... ~-•• i .... --~--····:· ••••• ~-····? .. ·:·. ~-. ·-~---:-.... ·:·-. · .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . ' . . . . ' . . . . . . . . . . . . . -.. :.. -.. :. -.... : ... --. -. -.. .:. -. : -.... -: -... -.. : .... -: ... -. : . -.: .. .: ..... .:. . . . . . . . . ' . . . . . . . . . . . ' . . . ' ................ ..-.... ·········· .. ,•· .. ; .... ;.. ···i···••\••··••:---i·····{····••:•-·· C: C: C: C: ... ... ... '-... >. >. >. >. >. >. >. >. >. -~ ·e ·e ·e ,:: .c ,:: ,:: ,:: .. .. .. .. .. .. .. .. .. ,:. ,J, "' N .,. "0 ~1 "i' "i' "i' "0 "i'"i' ~ J, ~ s ... N ,:. ... ~ isl ~ ~s ... Duration . . . . . • • • • • • • ~• • • • • • • • ~ • • • • • • • • • • • ~ • • • • • • • •:• • • • • • • • -:• • ••••I••••• . . . . ' . ' . . . . . ' ' . ' ' . ..... --:-. . . . . . ........ -..... ; . -. . ..... ~ - 2 s 10 25 so 100 200 500 1000 Average recurrence interval (years) NOAA Atlas 14. Volume 6. Version 2 Created (GMT): Tue Mar 24 22:26:12 2020 Back to Top Page 2 of 4 Average recurrence 1n1erval (years) -, 2 -5 -10 -25 -50 -100 -200 500 -1000 Duration -s-min -2-<lay -10-tnln -3-<lay I S-rnln -4-<lay -30-tnin -7-aay -60-tnln -1()-<lay -2-nr -2()-<lay -3-nr -3()-<lay -6-nr -45-day -12-hr -6()-<l8y 24-hr https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=33.1274&1on=-J 17.33 J 5&da... 3/24/2020 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 53 Precipitation Frequency Data Server Maps & aerials Small scale terrain .Carlsbad Large scale terrain rp111u11111." Ylt"ttlrYHle: MLl'netJ • ··-.I Oce:-,s,-•-1 Large scale map S rHa CttYil;a / 100km .,._ __ _,t ni En~cnad~ 0 Page 3 of 4 https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_printpage.html?lat=33.1274&1on=-J 17.33 J 5&da... 3/24/2020 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 54 Precipitation Frequency Data Server Back to Top US Department of Commerce National Oceanic and Atmospheric Administration National Weather Service National Water Center 1325 East West Highway Silver Spring, MD 20910 Questions?: HDSC.Questions@noaa.gov Page 4 of 4 https://hdsc. nws. noaa.gov/hdsc/pfds/pfds _pri ntpage. htm I ?lat=3 3. 127 4&1 on=-11 7.33 1 S&da... 3/24/2020 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 55 .... . .. . . " . ; . =~It C ;o •. :1. ... ·•!•:Jo: , ... ',~ I ;!I• -:?J.:. !JI.! \, $.. , .. ·,,,; ·. " .. \ .. ~. • . ---"I. ~-. . .. . • .. -;r~' -• .. ,,,' • . . I -.... ..... .. ,.-.. • \, 1 \ ·, \ i., -• \\ ·~~,\--'I • --.• ·, ~-~ '-.fia ' .. • I. . ,, ' •, \ \ \ MIC '· \ 1 I • ~ ... .. .. ,/" .,,., L ~ ' .i~ \ . ' \ ', \\ . ~ -• ... ' \ I ' -,,■ ~ '· \ \ ... '' i! '· .. ". ' I ' ~~. ' " . ~., •, ,.., I :, ' ,~,,~I 1:;1 °, ' •: \ . \ ~-} ~,tre(l l!:,:,i ,,;\;•],-] . . ~ \ -':t -·~., , \ , ~rH,,\ ,-.:;;,J.-s. \ ..., I ·, .. \ ,., ..•. • !t~. i!I ! :,:. •• ! . ,:.. . . '• .. ••"-~--::.•~ ~ -•••:.. , . ... ..... ,. -.... -•-r.:-: ·••:..1-..: ~, .. I I :; .. ... .. Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 56 Hydrologic Soil Groop-San Diego County Area, California MAP LEGEND MAP INFORMATION Area or Interest (AOI) Area of Interest (AO~ Soils Soll Rating Polygons □ A □ A/0 DB 0 BIO 0 C 0 Clll □ 0 D Not roled or not ovoioble Soll Rating Lines A A/0 B BIO C Clll 0 ~ -Not ra1ed or not ■valable Soll Rating Points C A a A/0 ■ B ■ BIO lJSO,\ Natural Resources --Conservation Service C C C CID 0 □ Not rated or not •voil•b~e Water Features Streams and Cimels Transponall on +++ Rails -Interstate Highways -US Routes Major Roods Lo"'I Roads Background • Aarial Photography Web Soil Survey National Cooperallve Soil Survey The soil surveys that comprise your AOI were mapped at 1:24,000. Werning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstancing of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based en the Web Mercator projection, which preserves drection and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of lhe version date(s) listed below. Soil Survey Area: San Diego County Area, California Survey Area Data: Version 14. Sep 16. 2019 Soil map uni ls are labeled (as space allows) for map scales 1 :50,000 or larger. Date(s) aerial images were photogaphed: Nov 3, 2014-Nov 22, 2014 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a resuff. some minor shi11ing of map unit boundaries may be evident. 3/24/2020 Page 2 014 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 57 Hydrologic Soll Group-San Diego County Area, California Hydrologic Soil Group Map unit symbol Map unit name Rating Acres In AOI Percent of AOI MIC Marina loamy coarse B 0.2 sand, 2 to 9 percent slopes Totals for Area of Interest 0.2 Description Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (f:,JD, BID, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential) when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potentia l, soils that have a high water table, soils that have a claypan or clay layer at or nea r the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (AID, BID, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group Dare assigned to dual classes. Rating Options Aggregation Method: Dominant Condition Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 100.0% 100.0% 3/24/2020 Page 3 of 4 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 58 Hydrologic Soll Group-San Diego County Area, California Component Percent Cutoff: None Specified Tie-break Rule: Higher Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 3/24/2020 Page 4 of 4 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 59 San Diego County Hydrology Manual Date: June 2003 Section: Page: 3 5 of26 Where: C = 0.90 x (%Impervious)+ Ci, x (l -% Impervious) Cp = Pervious Coefficient Runoff Value for the soil type (shown in Table 3-1 as Undisrurbed 1atural Terrain/Permanent Open Space, 0% Impervious). Soil type can be determined from the oil 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 pennaneut, the appropriate value should be selected based upon the soil and cover and approved by the local agency. 3-5 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 60 Cl) a. 0 cij -a, ~ ci5 ..... 20 18 16 14 12 10 9 8 7 5 4 3 0 * 1.! 1.6 1.4 1.2 1.0 0.9 0.8 0.7 0.6 0.5 0.4 1.--1.s·-----------1 l__,, = .015--..+,I _ 2% _,_____ n=.0175 ------::...:::_ ___ --..! 2% I L... I 3// __ ,.,_., <vL -~ C'.)·1 ff ~ --, I --- r--...__ ) I I r---.._ I I -----I t-.. I Conctele Gutter I I-- I ' ~-1 I --.i I I r-... 0.13 I I ----r---.. l J , ' I Paved f--.... ~ J ~ 10 ~ r--~6' I_ ~ J RESIDENTIAL STREET ONE SIDE ONLY .,..._ I,,~ I "'-..!....<r ·/:) I r'Z. -,........__ I I ~ I ' --......... -,..... I I ""' I I '"-..... -... 1,,"'6r I '--/... ---., I r1z__ I ...... ,.,_.,, ----J I'--. 11; ---~., s I f"-.-... I I (:, --........ s ..... J ~r-t 'ft ~ ~ I I'---~ t,: r--.._ I t ~ ~" I,__ I/ ~I/ I I"--cJ' ,__ !> .... -,.,_, I ...... qj /~ r--.. "" "s:,· r--.. I fol .......__ ,.,_(/) I i,-........__ ---c::f ""''?' .... ' ' r--....1 J ~3 J ff1 ....._,___ i'I I f_p I ~ o/ 1'--~L qj I ...... -,.,_"' /' v_,.? J I r---.. r----I ell " r---i1 r-.......:-sr I r!:_.s. r---... I I f l I'-.. I L J I J I ------J 'r---1 /"-...__ I cJ'I '.._ I ......... , I ,.........._ ___ I ---.........._, I ........ v_,.? , I I'-..... I .............._ I i--!P.,;_ j I ~ I ~/ I' I'...... -~ I "-..._ ........... "" I fl'...... ~I ...... 'I'...... .... ·P.s. j 2 3 5 6 7 8 9 10 20 30 40 50 Discharge (C.F.S.) EXAMPLE: Glvon: Q = 10 s ~ 2.5% Chart gives: Depth= 0.4, Velocity = 4.4 f.p,s. SOURCE: San Diego County Department of Special District Services Design Manual F I GU R E Gutter and Roadway Discharge -Velocity Chart ~ Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 61 EQUATION: V = 1.49 R"• s11> n 0.3 0.2 ro 0.2 f 40 0.3 t 0.15 f 30 0.4 0.10 0.09 l"' 0.08 20 0.07 0.06 0.6 0.05 ~ 0.04 0.8 "" 0.9 0.03 ~ 1.0 <?6' 10 "" > < 0.02 ll'. /' /] 8 ':' -a; "" 0 ~ 7 / ~ .2 .!= <ii Cl) <ii 6 ~ 0. a. / -a; 0.01 D 2 Y~ °Qi .S! 0.009 <I'. ~ ~ ll'. _i; 0.008 .G ~ ;# ~ w 0.007 ...J ~ ~4 a._ ::::> 0 0.006 3/ ...J rn <>: 0.005 ll'. D >-o.oo~&,--I ~ 0.002 0.001 0.0009 0.0008 0.0007 0.0006 0.0005 0.0004 0.0003 6 8 9 10 20 SOURCE: USDOT, FHWA, HDS-3 (1961) ""'8 ...J w > GENERAL SOLUTION Manning's Equation Nomograph 3 2 1.0 0.9 0.8 0.7 0.6 0.5 0.01 0.02 o'l-/ p C ' 0.03 c <l) ·u it: <l) 0.04 0 0 (/) (f) ~ r o.os I CJ O.OG ::::> 0 er: 0.07 0.08 0.09 0.10 0.2 0,3 0.4 I" '~_;REI Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 62 10.0 9.0 8.0 7.0 -;:-::, i OJ 6.0 5.0 I 4.0 I 3.0 I I 2.0 -fi _s1,0 i0,9 ·ji'lo.a ., ~0.7 0.6 j 0.5 0.4 0.3 I 0.2 ~, r-... r-... ' r-.. ' ... ..... , ... r,.. I'-.. .... ....... I'-I'-.. I'-.. .... ,, ... i,. ' r-...r-.. ........ .... ' i,..i,. ,... i,., ..... '"'r-... ... ......... ,... i' '~, 'r-.. ..... ' ,... ', "i,... i,. '~ ..... r-... ... I'-. ' ~ .... 'r-.. ~ ~ ' 'i-.. '~ ' ... .... , ""• ~ .... i,..,... ~ ..... ~ 'r-.. , ..... '~ 'i,.. '~ r-.. .... , r-.., ..... '~ '~ ....... ',~ ~, ~ i j ~ ~1~ 15 20 30 Minutes 11 ~ ~ ~ ~ ~ ~ 40 50 1 0uraUon 11111111111 11111 :I 1111111111 11111 I 1111111111 11111 I EQUATION I = 7.44 P6 D.o.545 11 = Intensity (in/hr) Ps = 6-Hour Precipitation (in) D = Duration (min} 'i,... , .... "" 1'-i,. I'-.. ..... 1, 'i-.. I• ,,... I'-...._ ..... ,, ~ • 1,, :-., ., ~ ' ' ~ I'-.. ..... ,, . I'-. ' .... , 1', .... ""' ' ... 'i,. I'-·, 'i,... ......... 2 3 4 Hours I" I 5 6 ~ s ~ i n M~ u~ ug u~ •~a 35~ J,O 2.5 2.0 1.5 1.0 Intensity-Duration Design Chart -Template Dlrec:tlons 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 appllcaple 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 I.he intensity-duration curve for the location being analyzed. AppllcaUon Fonn: {a} Selected frequency ..fQQ_ year {b) P5 = '2., >I in., P24 = 1i to 'PP5 = _il %12) 24 (c) Adjusted p6t2l = __ in. (d) 'x = __ min. (e) I = __ in.fhr. Note: This chart replaces the Intensity-Duration-Frequency curves used since 1965. I P6 1 1.5 2 2.51313.5 4 4.5 5 I 5.5 i 6 OuraUon I I I I I I I I I I I I i I 5 2.63 3,95 5.27 6,59 7.9019,22 10.5-4 11.86p3.17 14~,~ 7 2.12 3,18 4.24 5.30 6.36°7.42 8.48 9.5-4 i 10.60 11,66 12.72 --,-0 1.68 2.53 3,37 4.21 5.05 5.90 6.74 7.58 I 8.42 9.27 I 10.11 15 1.30 1.95 2.59 3.24 3.89 4.541 5.19 . 5.84 I 6.49 7.13 [21!_ 20 1.08 1.62 2.15 2.69 J.23 3.TTI 4.31 4.85 I 5.39 5.93 16.46 --rs 0.93 ~ 1.87 2.33 2.80 J.211 J.73 I 4.20_,~ 5.13 5.6o ~ 1183 1.24 1.66 2.07 2.49 2.90 3.32 3.73 4.15 4.56 4.98 40 0.69 1.03 1.38 1.72 2.07 2.41 2.76 ±!.Q_[ 3.45 ( 3.79 j 4.13 50 0.60 0.90 1.19 1.49 1.79 2.09 2.39 2.69 2.98 i 3.28 3.58 60 0.53 0.80 -~ ~ 1.59[ 1.86 2.12 2.39 2,65 ! 2.92 3.18 90 0.41 0.61 0.82 1.02 1.23 1.43 1.63 1.84 i 2.D4 I 2.25 i 2.45 120 0.34 0.51 0.68 0.85 1.02 1. 19 1.36 1.531 1.7~ 1.87.!i 150 0.29 0.44 0.59 0.7310,88 1.03 1.18 T52f 1.47 1.62 1.76 180 0.26 0.39 0.52 0.6510,78 0.91 T.o4° 1.1s 0T3Tl1.44 1.s1 240 0.22 0.33 0.43 0.5-410.65 0.76 0.87 ¥aH 1.08 FPof 1.30 ~ 0.19 0.28 0.38 0.4710.56 0.66 0.75 0.85 lf.94"1.0fi 1.13 360 0.17 0.25 0.33 0.4210.50 0.581 0.67 0.75 I 0.84 I 0.92 I 1.00 FIGURE ~ Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 63 10.0 9.0 8.0 7.0 6.0 5.0 I 4,0 I 3.0 I I 2.0 -.::-~ a, ~1.0 ~0.9 -~0.8 io.1 0.6 0.5 0.4 0.3 I 0.2 ! 0.1 I'-. I'-. .... ""' i-.. i' ' , .... r-,. I'-. ' ,,/' ' ~ ', r-,. I'-."" ......... '. ' ' ~-I I"', .... ~ ' . ""~ "' ~ -~ r-,.r-,. , i""i-.. "'~ ~-~ , .... ' .... ~ I'--~ ,i-.. -~ ' l"'i,.~ -~ ·, ..... I',, , I" .... -~ .... r-,.r-,. '". ' ' 'r,.. i-..1"-. ~ .... ' , .... ~ "'· ~-~ 5 i; 7 8 9 1·0 15 20 JO Minutes ~ ~ ~ ~~~ ~ 40 50 1 Duration 1111111111 11111 1111111111 11111 1111111111 11111 EQUATION I = 7.44 Ps o-0.645 I = Intensity (in/hr) Ps = 6-Hour Precipitation (in) D = Duration (min) i-..,.... ,, r--"" "'i,. ..... ........ ' ~ I• 'i,. ..... ..... .... ' . :-,, I', .... "'"' "'"' ~-I"'._ r-., I',!', ' I', ' r,.. I', I"' :-,, I',~ ' ~I', ... -~ ii-.,.... ~ , .... 2 3 4 Hours II II II I I 5 6 a, :'t 0 !,; ,, iil Q. 6.0 'E. 5.5 ~-5.0 g 4.5 '"§' " 4.0 ~ 3.5 .e 3.0 2.5 2.0 1.5 1.0 Intensity-Duration Design Chart -Template Directions for Application: {1) From precipitation maps delermine 6 hr and 24 hr amounts for the selected frequency. These maps are included in lhe County Hydrology Manual (10, 50, and 100 yr maps induded 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 lhe 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 /0 year (b) Ps = _&_1n., P24 = ~:6 = izL %(2) 24 (c) Adjusted P6f2> = __ in. (d) 1x = __ min. (e) I = __ in.lhr. Note: This chart replaces the Intensity-Duration-Frequency curves used since 1965. _1_ 15_1-Hw.J 3.5 I 4 145 I I I~ ,~ 5 I sis 6 Ouralloo I I I I I I I I I I I 5 2.63 l3.95l5.27l~901!1.22 10,54 11~86Jl3.17 14.49) 15.81 7 2.12 13.18 4.24 5.30 6.36 7.42 8.48 9.64 10.60 11--:Sei 12.12 10 1.68 12.53 J.3714.2115,05 5.90 8.74 7.581 8.42 9.27 iTo.IT 15 1.30 1.9S 2.591 3.24 13.89 4.54 5.19 5.84 I 6.49 7.13 I 7.78 ~ 1.08 1.62 z.,s,2.6913,23 J.77 4.31 4.85 s.39 5.93 I 6.•s 25 0.93 1.~ 1.87 2.33 !2,80 J.;rr J/[3J.!1Q__ 4,67 5.1315.60 ~ 0.83 1.2411.66 2.0712,49 2.90 3.32 ~-~5 4.56 4.98 ,o 0.69 1.03 1.3!!__1,Z~_J2.07J2.41, 2.76 ..L!._O ! 3.45 -3.79 4.13 --sci ~ 0.90 1.19 1.4911.79 2.091 2.39 2.69 I 2.98 3.28 I 3.58 60 0.53 0.80 I.Cl§_ 1.3Jj 1.59 1.8~12.12 il2.65 2.92 j 3.18 I 1: 0.41 0.61 0.82 1.0211.23 1.43 1.63 ,.~ 2.04 2.25 j 2~ 0.34 0,51 0.68 0.85 1.02 Ll9i 1.36 1.53 1.70 1.87 2.04 ~ 0.29 0.44 0.59 0.73 0.88 1.03° 1.18 1.32 1.47 1,62. 1.76 180 0.26 0.39 0.52 0.65 0.7Bfo.91 f:°04 ill . 1.31 1,4411$ 240 0.22 0,33 0.43 0.54 0.65 0.76 0.87 0.98 t 1.08 1,19 ! 1.30 300 0.19 0,28 0.3B 0.47 0.56 0.66 0.75 0.85 . 0.94 1.03 I 1.13 360 0.17 0.25 0.33 0.42 0.5010.58 0.67 0.75 0.8'1 I 0.92 I 1.00 FIGURE ~ Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 64 San Diego County Hydrology Manual Date: June 2003 3.2 DEVELOl'lNG I.NP T DATA FOR THE RA no AL METHOD Section: Page: 3 20 of26 This section describes the development of the necessary data to perfonn RM calculations. Section 3.3 describes the RM calculation process. Tnput data for calculating peak flows and Tc's with the RM should be developed as follows: l. On a topographic base map, outline the overall drainage area boundary show~g adjacent drains, existing and proposed drains, and overland Dow paths. 2. Verify the accuracy of the drainage map in the field. 3. Divide the drainage area into subareas by locating significant points of interest. These divisions should be based on topography, oil type, and Jand use. Ensure that an appropriate first subarea is delineated. For natural areas, the first subarea flow path length should be less than or equal to 4,000 feet plus the overland flow length (Table 3-2). For developed areas the initial subarca flow path length should be consistent with Table 3-2. The topography and slope within the initial subarea should be generally uniform. 4. Working from upstream to downstream, assign a number representing each subarea in the drainage system to each point of interest. Figure 3-8 provides guidelines for node number for geographic infonnalion system (GIS)-based studies. 5. Measure each subarea in the drainage area to determine its size in acres {A). 6. Determine the length and effective slope of the flow path in each subarea. 7. Identify the soil type for each subarea. 3-20 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 65 Study Area SC / .. ··1 I . : ·1 l._.. ~ t / -. ,./ L-· Study Area LA 0 Define Study Areas (Two-Letter ID) 0 Define Maps (or Subregions on Region Basis) 0 Define Model Subareas on Map Basis ' . . , ' ~#~ / #--1 .. ___ _ __ ... 0 Define Major Flowpaths in Study Area @ Define Regions on Study Area Basis Subarea ID== (LA010112) Ni:::_ l Region# ,...., Area (ID) # l 1 l © Define Model Nodes (Intersection of Subarea Boundaries with Flowpath Lines) GIS/Hydrologic Model Data Base Linkage Setup: Nodes, Subareas, Links LA 01 01 03 0 Number Nodes I'·~_-; El Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 66 San Diego County Hydrology Manual Date: June 2003 Section: Page: 3 22 of26 8. 'Dete1mine the runoff coeflicient (C) for each subarea based on Table 3-1. If the subarea contains more than one type of development classification, use a propo1tionare average for C. In detenn.i.ning C for the subarea, us<:: future land use taken from the applicable community plan, Multiple pecies Conservation Plan, National Forest land use plan, etc. 9. Calculate the CA value for the subarea. 10. Calculate the I:(CA) vaJue(s) for the subareas upstream of the point(s) of interest. 11. Dctennine P6 and P24 for the study using the isopluvial maps provided in Appendix B. If necessary, adjust the value for P6 to be within 45% to 65% of the value for P24. St:e Section 3.3 for a description of the RM calculation process. 3.3 PERFORMING RAT.TO AL METHOD CALCULATIONS This section describes the RM calculation process. Using the input data, calculation of peak flows and Tc's should be performed as follows: 1. Determine T; for the first subarea. Use Table 3-2 or Figure 3-3 as discussed in Section 3.1.4. If the watershed is natural, the travel time to the downstream end of the first subarea can be added to T; to obtain the Tc. Refer to paragraph 3.1.4.2 (a). 2. Dete1mine I for the subarea using Figure 3-1. If T; was less than 5 minutes use the 5 minute time to determine intensity for calculating the flow. 3. Calculate the peak discharge flow rate for the subarea, where Qp = E(CA) I. In case that the downstream :flow raLe is less than the upstream flow rate, due to the long travel time that is not offset by the additional subarea runoff, use the upstream peak flow for design purposes until downstream flows increase again. 3-22 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 67 San Diego County Hydrology Manual Date: June 2003 4. Estimate the Tt LO the next point of interest. 5. Add the T1 to the previous Tc to obtain a new Tc. Section: Page: 6. Continue with step 2, above, until the final point of interest is reached. 3 23 of26 Note: The MRM should be used to calculate the peak discharge when there is a junction from independent subareas into the drainage system. 3.4 MODI FIED RATIONAL METHOD (FOR JU CTION ANALYSIS) The purpose of th is section is to describe the steps necessary to develop a hydrology repmt for a small watershed using the MRM. It is necessary to use the MRM if the watershed contains junctions of independent drainage systems. The process is based on the design mrurnals of the City/County of San Diego. The general process description for using this method, including an example of the app lication of this method, is described below. The engineer should only use the MRM for drainage areas up to approximately I square mile in size. If the watershed will significantly exceed I square mile then the NRCS method described in Section 4 should be used. The engineer may choose to use either the RM or the MRM for ca!ClLlations for up to an approximately I-square-mile area and then transition the study to the RCS method for additional downstream areas that exceed approximately square mile. The transition process is described in Section 4. 3.4.1 Modified Rational Method General Process Description The general process for the MRM differs from the RM only when a junction of independent drainage systems is reached. The peak Q, Tc, and I for each of the independent drainage systems at the point of the junction are calculated by the RM. The independent drainage systems are then combined using the MRM procedure described below. The peak Q, Tc, and 1 for each of the independent drainage systems at the point of the junction must be ca.I cu lated prior to using the MRM procedure to combine the independent drainage systems, as these 3-23 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 68 San Diego County Hydrology Manual Date; June 2003 Section: Page; 3 24 of26 values will be used for the MRM calculations. After the independent drainage systems have been combined, RM calculations are continued to the nex.t point of interest. 3.4.2 Procedure for Combining Independent Drainage Systems at a Junction Calculate the peak Q, T0, and T for each of the independent drainage systems at the point of the junction. These values will be used for the MRM calculations. At the junction of two or more independent drainage systems, the respective peak f1ows are combined to obtain the maximum flow out of the junction at Te. Based on the approximation that total runoff increases directly in proportion to time a general equation may be written to determine the maximum Q and its corresponding Te using the peak Q, Te, and l for each of the independent drainage systems at the point immediately before the junction. The general equation requires that contributing Q's be numbered in order of increasing T0• Let Qi, T1, and I1 co1Tespond to the tributary area with the shortest Tc-Likewise, let Q2, T 2, and h correspond to the ttibutary area with the ne,....-t longer T0; Q3, T3, and h correspond to the tributary area with the next longer Tc; and so on. When only two independent drainage systems are combined, leave Q3, T3, and I3 out of the equation. Combine the independent drainage systems using the jw1ction equation below: Junction Equation: Ti < T2 < 3 3-24 Patel Residence, Terramar, Carlsbad Boulevard bha, Inc. Drainage Study land planning, civil engineering, surveying 69 San Diego County Hydrology Manual Date; June 2003 Section: Page: 3 25 of26 Calculate QTI, Qr2, and QTJ. Select the largest Q and use the T0 associated with that Q for further calculations (see the three Notes for options). If the largest calculated Q's are equal (e.g., QT1 = Qn > Qn), use the shorter of the Tc s associated with that Q. This equation may be expanded for a junction of more than three independent drainage systems using the same concept. The concept is that when Q from a selected subarea (e.g., Q,) is combined with Q from another subarea with a shorter Tc (e.g., Q1), the Q from the subarea with the shorter Tc is reduced by the ratio of the l's (12/T1); and when Q from a selected subarea (e.g., Q2) is combined with Q from another subarea with a longer Tc (e.g., Q3), the Q from the subarea with the longer Tc is reduced by the r'dlio of the Tc's (T2/T3). Note #1: At a junction of two independent drainage systems that have the same Tc, the tributary flows may be added to obtain the Qp- This can be verified by using the junction equation above. Let Q3, T3, and !3 = 0. When T1 and T2 are the same, 11 and Ii are also the same, and T1/T2 and Ii/11 = I. Ti/f 2 and 12/11 are cancelled from the equations. At this point, Q·n = Qn = Qi + Qi. Note #2: In the upstream part of a watershed, a conservative computation is acceptable. When the times of concentration CTc's) are relatively close in magnitude (within 10%), use the shorter Tc for the intensity and the equation Q = :E(CA)I. Note #3: . An optional method of determining the Tc is to use the equation Tc -[CL (CA)7.44 P6)/Q] us This equation is from Q = :E(CA)I = :E(CA)(7.44 PJT064 " ) and solving for Tc. The advantage in this option is that the Tc is consistent with the peak flow Q, and avoids inappropriate fluctuation in downstream flows in some cases. 3-25 NO. r' 121 131 [±] rs 1M [2) r:: .. _ t-~-; -· ----:-•~,,=":Iii --1, - -,_ ---- 83+00 84+00 [j]/ ,· () 84 0 ~ /-rd' AC Wate r ~I/ ~ ~ 0 / If) STORM DRAIN DATA DEL TA OR BRG. RADIUS LENGTH REMARKS .S 30' 4/' .¾" E ISl'.0'' . 30" fi'CP S30'41'5,lo"E 2200' 30" RCP 5-30•4f5/i,''E 252.D' 24" RCP S 30• 4f 5c,," E 251.0' z4,• RCP s-30•4r5,.•1c 9 1.0· 18" RCP N 59"18'04"E 1c..2· 18" RCP S 30°41's(;1 E 235-0'" .30"RCP :.=:..:.::::: 85+00 86+00 . -:,=,+~,-, ____ ;_,_.,''.",_;;-' -~ :' --.,,,,:;-~~E- ~~ ," '"'""•t' .;:;.:; ~. . '.::r::~::: :::,;;_ .. :er::,. cc::,.·::£:.:,,_ --~--.;. =i=;.. ·.=:-..::.:· .. -:c' E t=,. ~.c=i ::' .. -- ·:.::...l ~ ,:~i:;J;::'~ ~-- ·•·-:c:.r.: ·.c_r · .::.f '-:· - -:: :;=; -""'lc5c c',-,; - 87+00 88+00 89+00 90+00 Sea le.: I" c 4o' t 12':t,pe A-l·(Mod;f ,ed) S'e:e. Cet .. ,l:Be.losoi:c.._ Curb /n /et "3 Sta 89 <OIP i Type A C.O. "'4 SI• 89+01P, 15' Lt See Note o.-, -----.._ \ · Snee+ 13. ~ Nofe:·-~Storni Drain •t.4'#ifr0f"ProfHe . -. ;ihown. .o.n 11 Storm. Cro.tn·Proftr- .. --·<lnd D,:to,b ''. <,h,,t. 14. LiJ > a: C 0 N w a:: w· u \.. MODIFIED TYPE A-I INLET No Scale 91 +oo t Tvc• A C.O. *3 St<191•58, 15 'Lt. ·;:,:. 92+00 93+00 = -~:-!:r . ==-· ---·-· 94+00 Exir,fin9 Inlet ' 18" IT. 1 .C.F.~-(to remain) ~ -·-'--: ~--. ~-- . ::,-~~: :;· -1::~;;f-";:--- 95+00 <t Type A'C.O. "2 Sta 94+09 , 15' Lt . +,, " .. ..c I I <n -::.,1. + ..... _.-+:i-----: 1/) ~ CITY OF CARLSBAD IISH!ETSI 1--t-+------------'----+--i ~ ENG I NU IIING OE PAR HIE!IT 2(& t--t-1-------------+--t t---+-+-----------+-----t CARLSBAD BOULEVARD IMPROVEMENTS OAT€ IIY OESCRI PTION APP'O REVISIONS STORM DRAIN PLAN 8c PROFILE STA 83+00 TO STA 95 + 00 APP'/'~ rf,{, . II /I IIE. '7:Z.ff'(// CITY ENGIN[EII PIIOJECT NO. II 3 205 _ ~l'WING NO. 270-2 J.N,270 l l. 'l NO. 111 fzl cj-°'_-·• -_ .,_;,,_•,f· ::.. 95-+00 STORM DRAIN DATA DEL TA OR BRG. RADIUS LENGTH REMARKS s 30°41'54>" E 209 IB"RCP 5 37°25 5S'E 13e' 18" RCP Note , len9th shown is from <;;_ 6fructure to -~ •. ~-"j:$- =,;::. :,:·f~ ~ ~a-::: .. :L F' -r i:::f£:::i= :;:~;r---- ·,,+t,_ -:g:~ ~. cJi:•. ~-f-:.:: - ;.;:. :_::::: .. -::~==-:·· ·-+•· ,,:·· ~~-4Unfi7!·· --'P:5i 4, _ -~t ~-b-:&;: _:·_L -i 96+00 97+00 98+00 ~ If Ty~-eeo. · * I 5ta 97•09, 15' Lt . structure {. 15' T~pe A -1 ("'1odified) :. I Curb lnlef "'I t !e,t,, 98+~, 32'L. I I \_-R/W Scale: l11=4o' --'•·,-oc-',.· c ..• ·-·····;"::..:.': .. :t:: ;·:"'::~::.ft. ··-·:::~ ::_;.~::..· ----=~;;;:::·:::.--i:, •. B Mftftfii~;I:_!~~ : ;': -···-·;.···-.-. . ·- 99+00 I ., __ ,., .... =- BOULEVARD :-·,~: -~--.=1: . -~ts;. .. .:·r:.t - ==£cc*•·~ ·-+-;J\ . ,-~~i-.::....:..,._ . '. ,. ; TNUT l t;vr rc11 TRANSI7JON GllTTEA TAAHSITION . ---~10~·----------+----"'0::.'----~ TOP 0, Cl.JR~-"/ I lNl[f WllJTH SHO""" ON PLANS £l£VATION. ...:~~- ·:.·-:J.= 9::::. ··:· ---~ 7. -- ::_ '": ·c:~ ·....:..... CllR8/'ROFIL£-/Nl[T:J•--: • i:::r=::i===============~:::::c:~J'r.l s~H~EE~T,;I =c~1;;r~v~ol!!F~c~A~R~L~s;;;;agA~o~1~1s~_HE:;::;£::::::;Ts=ril i f3 ENGINECPIINO DEPARTMENT 2(;:, J./'tl70