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HomeMy WebLinkAboutCT 05-18; Seascape; HYDROLOGY CALCULATIONS; 2013-09-211f .. 27· (3 HYDROLOGY CALCULATIONS FOR SEASCAPE (TENTATIVE MAP NO. CT 05-18) CITY OF CARLSBAD RECEIVED NOV 2 7 2013 LAND l.JL.. v cLOt-, __ r· .. • ENGINEERING 5 1269DS.PM5 HYDROLOGY & HYDRAULIC CALCULATIONS FOR SEASCAPE CITY OF CARLSBAD Rev Sept. 21, 2013 Rev. October 18, 2012 Rev. August21, 2012 June 25, 2012 Job No. 1269 R. BHATIA, M.S., P.E. R.C.E. #051348 Exp. 6-30-14 Prepared By: CIVCOM & ASSOCIATES 6540 Lusk Blvd. Suite C135, San Diego, California 92121 Phone: (858) 658-9400 Fax: (858) 658-9420 ·CIVCOM Certification 1.0 General Background 2.0 Existing Conditions Vicinity Map Attachment A TABLE OF CONTENT Hydrology Map-Pre-Development Condition 3.0 Methodology 3.1 Rational Method 3.2 Confluence Method 4.0 Hydrology Computations & Results 4.1 Proposed Storm Drain Facilities 4.2 Post Development Condition Hydrology Map-Post-Development Condition Computations-1 0 yr Storm Computations-1 00 yr Storm Hydrology Results 4.3 Existing Capacity in Black Rail Road Computations-100 yr Storm Computations-1 0 yr Storm 4.4 Inlet Design at Avena Court East 5.0 Conclusions & Recommendations References Appendices Attachments B, C & D Maps 1. Exhibit 1 -On Site-Pre Development Condition 2. Exhibit 2-On Site-Post Development Condition 3. Exhibit 3 -Black Rail Road -Post Development Condition Page 1 2 2 3 3 4 5 5 5 6 6 7 CIVCOM CERTIFICATION 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 stadards . . I understand that the check of the 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. R. Bhatia, R.C.E. 51348 Registration Expires 06-30-14 -1 - 3-ol-~4. Date CIVCOM 1.0 GENERAL BACKGROUND This report presents a drainage study for the Seascape project. The project is located east of Black Rail Road and north of Avena Court East in the City of Carlsbad (see Vicinity Map). The proposed site consists of approximately 4.4 acres adjoining Black Rail Road to the West and Avena Court to the South, Carlsbad Tract No. 99-10 adjoins to the North and Carlsbad Tract No. 97-20 adjoins on the South of Avena Court East. Currently the site is vacant and has, in the past, been used for agricultural purposes. There are no existing permanent structures on this property. The proposed development consists of a 12 lot single family residential subdivision. 2.0 EXISTING CONDITIONS There are no existing off-site storm runoff flows entering the site. The existing brow ditch, inlets located North of the boundry intercept all the flow fron the north. These inlets deliver the flow to the east via 18"pipe and a brow dich with riprap at the eastern end. There is a ridge line on the subject site that splits the existing drainage into two basins as shown on the map. This drainage study includes a Hydrology Study for the basins 100 and 200 (see Hydrology Map-Exhibit 1 ). The basin 100 is located along the east side of Black Rail Road. In the pre-development condition, this basin consists of approximately 3.2 acres which currently contributes storm runoff to an existing brow ditch outlet to existing curb & gutter on the east side of the Black Rail Road; and the runoff ultimately flow to existing 8' B-1 inlet in the Black Rail Road at Sta 10+81.95. The basin 200 is located along east side of the property. In the pre-development condition, this basin consists of approximately 1.6 acres which currently contributes storm runoff to adjacent property at the southeast corner of the property. All runoff from the site eventually drains to the Batiquitos Lagoon (see ATTACHMENT A). -2- CIVCOM CAMINO REAL ? f\LOMAR ~\RPORT RD . --- -AVIARA PKWY. <(--~ ·~· VICINITY MAP NOT TO SCALE ATTACHMENT A HYDROLOGY STUDY CT 05~18 3.0 METHODOLOGY 3.1 RATIONAL METHOD The Rational Method as described in the San Diego Hydrology Manual, Section 3, (Revised June 2003) shall be used to determine storm runoff. The Rational Method formula is expressed as follows: Q=CIA Where: Q =peak discharge, in cubic feet per second (cfs) C =runoff coefficient, proportion of the rainfall that runs off the surface. I =average rainfall intensity for a duration equal to the T c for the area, (in/Hr.) A= drainage area contributing to the design location, in acres. The coefficient C has no units and is based on the soil group and the percentage of impervious area for the drainage sub-area. Attachment F included calculations for the percent of impervious area for each drainage sub-area. The following values are used in the calculations: Soil Group D from San Diego County Soils Group Map. See Attachment B. Runoff coefficient, ("C") from Table 3-1. See Attachment C. 10 year 6 Hr. Rainfall = 1.5" from See Attachment D. 10 year 24 Hr. Rainfall= 3.1" from See Attachment D. 100 year 6 Hr. Rainfall = 2.6" from See Attachment D. 100 year 24 Hr. Rainfall = 4.4" from See Attachment D. Time of concentration is derived from the equation Tc=(11.9 L3/H}-385 X60 minutes. -3- CIVCOM For basins where time of concentration is less than 8 minutes, a minimum value of 8 minutes is used. Travel time in pipes is calculated by equation L I (V*60). Each sub area is calculated individually for time of concentration with longest aggregate time being the total time for the site. Intensity is derived from the equation in Intensity chart. I = 7.44 p 6Q-.64s The site is first divided into drainage sub-areas. See the On-Site Hydrology Maps in Attachment B. The time of concentration, Tc, for each sub-area along the drainage path is computed based on the initial time of concentration for the initial area and the travel time to reach each succeeding node. Based on the time of concentration, the rainfall intensity is determined using Figure 3-2 (See Attachment D). Then applying the rational method equation, the peak runoff is determined at each node along the drainage path. Q's are tabulated for each sub-area along drainage path. 3.2 Confluence Method Let Q, T and I correspond to the tributary with the largest discharge. Let q, t, and i correspond to the tributary with the smallest discharge. Let Q, and T correspond to the discharge and the time of concentration when peak flow occurs. If T > t, the peak discharge is corrected by the ratio of the intensities: Q = Q + q(l/i) and T=T. If T < t, the peak discharge is corrected by the ratio of the times of concentration: Q=Q+q(T/t) and T=T. -4- CIVCOM 4.0 HYDROLOGY COMPUTATIONS & RESULTS 4.1 PROPOSED STORM DRAIN FACILITIES Hydro modification low flow node 207 to node 206 on west side of Surf Crest Street is intercepted by a proposed Filterra Bio-Retention inlet F2 and processed. Hydromodification low flow node 208 to node 209 on east side of Surf Crest Street in intercepted by a proposed Filterra Bio-Retention inlet F1 and processed. Outlet of 6" PVC carries the flow from F1 and combined with oulet pipe from F2 and carries it in 6" PVC northwestly direction through the SDG&E easement. This flow outlets in a brow ditch D-75 that carries it to a D-25 outlet (R3) at node 111. Low flow from node 111 flows southerly in Street A and it is intercepted by Filterra Bio- Retention inlet F3 and F4. The outlet flow from F3 and F4 is combined to 17' type B-1 inlet K at node 121 Avena Court East which conveys the flow to an existing 24" storm drain in Black Rail Road. The table on the following page summerizes the above inlets, capacities and their functions. 4.2 POST -DEVELOPMENT CONDITION In the post-development condition, a new inlet is proposed at approx. Sta 1 0+60 of Avena Court East sized to receive all the flow from Basin 100 & flow from Basin 200 as shown on the attached Exhibit 2. Western portion of the Basin drains to a Filterra Inlet (F2) that drains to the drainage swale thru the Open space lot and carries the runoff to the North end of the private Street A. Eastern portion of the Basin also drains to a Filterra Inlet (F1) that drains to the drainage swale thru the Open space lot and carries the runoff to the North end of the private Street A. The runoff from the south eastern portion of the Basin 200 sheet flows to the southeast corner. The new proposed inlet at Sta 1 0+60 in Avena Court East will be connected via a 18" pipe to the existing 24" RCP storm drain in Black Rail Road at approx. Sta 14+90. The following pages summarize the storm runoff computations for 1 0-yr event and 1 00-yr event and results for the Post-Development conditions. -5- CIVCOM SESCAPE CT 05-18 Storm Drain Facilities ID No. Facility TYPE LOCATION 10 No. F1 FILTERRA SURF CREST ST. STA 2+19 F2 FILTERRA SURF CREST ST. STA2+15 F3 FILTERRA STREET A STA 0+75 F4 FILTERRA STREET A ST A 0+45 R3 0-25 CDS STREET A ST A 2+ 72 K TYPE B-1 INLET AVENA COURT EAST STA ·10+60 FILTERRA LOCATION AREA UNITID (ACRES) F1 SURF CREST ST 0.14 F2 SURF CREST ST 0.14 F3 STREET A 0.22 F4 STREET A 0.22 SEASCAPE CT 05-18 Filterra Inlet Sizing INTENSITY RUNOFF Q Q IN/HR CO-EFF CFS GPM 0.2 0.95 0.0266 12 0.2 0.95 0.0266 12 0.2 0.95 0.0418 19 0.2 0.95 0.0418 19 *PER MANUFACTURER FIL TERRA INLET MEDIA PROCESSES 1.0 GPM/ SF. FILTERRA CAPACITY ADEQUATE SIZE* GPM 4X4 16 YES 4X4 16 YES 4X6 24 YES 4X6 24 YES PROJECT: SEASCAPE JOB No .: 1269 FROM TO U/S NODE NODE ELEV BASIN 100 101 102 339.00 103 104 344.00 110 111 356.00 111 112 344.00 112 112 112 121 327.00 BASIN 200 203 204 358.00 204 206 356.00 205 206 358.00 CT99 207 367.00 207 206 358.00 206 206 201 202 359.00 CT99 208 378.00 208 209 358.00 209 121 354.00 121 121 202 230 354.00 1248ds.xls DS LENGTH ELEV FEET 336.00 210.00 328.00 320.00 348.00 220.00 328.00 260.00 322.00 150.00 356.00 150.00 354.00 180.00 353.00 140.00 356.00 150.00 354.00 220.00 354.00 170.00 356.00 330.00 354.00 220.00 322.00 480.00 342.00 160.00 10 -Year Storm Ti Tc INTENSITY SUB. MIN MINUTES (IN/HR) (ACRES) POST -DEVELOPED WITH CT 99-10 2.46 10.00 2.50 0.81 2.10 8.00 2.80 0.81 1.78 8.00 2.20 0.55 1.65 9.65 1.95 0.43 9.65 1.95 2.60 1.37 11.02 1.80 2.60 1.95 8.00 2.80 0.15 2.41 10.41 2.40 1.27 8.00 2.80 0.20 1.01 8.00 2.80 0.40 2.32 10.32 2.42 0.14 10.32 2.42 0.89 1.58 8.00 2.80 0.53 1.93 8.00 2.80 1.00 2.32 10.32 2.35 0.14 2.57 12.89 2.40 0.39 11.02 1.80 1.05 8.00 2.80 0.30 c CA TOTAL CA 0.49 0.40 0.40 0.49 0.40 0.40 0.35 0.19 2.46 0.90 0.39 2.85 1.57 -1.57 0.49 0.07 0.07 0.07 0.35 0.07 0.07 0.90 0.36 0.36 0.90 0.13 0.49 0.63 0.49 0.26 0.26 0.90 0.90 0.90 0.90 0.13 1.29 0.90 0.35 2.27 3.84 0.35 0.11 0.11 Q (CFS) 0.99 1.11 5.41 5.55 3.07 2.83 0.21 0.18 0.20 1.01 1.18 1.52 0.73 2.52 3.02 5.44 6.91 0.29 SHEET 1 OF 2 11/22/2013 REMARKS Initial Area Initial Area Grass Area Street Flow Confluence Street Flow Initial Area Street Flow Initial Area Street Flow Street Flow Confluence Initial Area Street Flow Street Flow Street Flow Confluence Grass Area PROJECT: SEASCAPE JOB No.: 1269 FROM TO U/S NODE NODE ELEV BASIN 100 101 102 339.00 103 104 344.00 110 111 356.00 111 112 344.00 112 112 112 121 327.00 OS ELEV 336.00 328.00 348.00 328 .00 322 .00 BASIN 200 PLUS OFF-SITE 203 204 358.00 356.00 204 206 356.00 354.00 205 206 358.00 353.00 CT99 207 367.00 356 .00 207 206 358.00 354.00 206 206 201 202 359.00 354.00 CT99 208 378.00 356.00 208 209 358.00 354.00 209 121 354.00 322.00 121 121 202 230 354.00 342.00 1248ds.xls LENGTH FEET 210.00 320.00 220.00 260.00 150.00 150.00 180.00 140.00 150.00 220.00 170.00 330.00 220.00 480.00 160.00 100-Year Storm Ti Tc INTENSITY SUB. MIN MINUTES (IN/HR) (ACRES) POST -DEVELOPED CONDITION 2.46 10.00 4.30 0.81 2.10 8.00 5.00 0.81 1.78 8.00 3.80 0.55 1.65 9.65 3.50 0.43 9.65 3.50 2.60 1.37 11 .02 3.30 2.60 1.95 8.00 5.00 0.15 2.41 10.41 4.20 1.27 8.00 5.00 0.20 1.01 8.00 5.00 0.40 2.32 10.32 4.20 0.14 10.32 4.20 1.58 8.00 5.00 0.53 1.93 8.00 5.00 1.00 2.32 12.25 3.90 0.16 2.57 14.82 3.30 0.39 14.82 3.30 1.05 9.05 4.80 0.30 c CA TOTAL CA 0.49 0.40 0.40 0.49 0.40 0.40 0.35 0.19 0.47 0.90 0.39 0.95 1.57 -1.57 0.49 0.07 0.07 0.07 0.35 0.07 0.07 0.90 0.36 0.36 0.90 0.13 0.13 0.63 0.49 0.26 0.26 0.90 0.90 0.90 0.90 0.14 1.04 0.90 0.35 2.28 3.86 0.35 0.11 0.11 Q (CFS) 1.71 1.98 1.77 3.32 5.50 5.19 0.37 0.31 0.35 1.80 0.53 2.64 1.30 4.50 4.07 7.54 12.73 0.50 SHEET 1 OF 2 11/22/201 3 REMARKS Initial Area Initial Area Grass Area Street Flow Confluence Street Flow Initial Area Street Flow Initial Area Street Flow Street Flow Confluence Initial Area Street Flow Street Flow Street Flow Confluence Grass Area PROJECT: SEASCAPE JOB NO.: 1269 FROM TO UIS OS NODE NODE ELEV ELEV BASIN 100 100 110 358.00 348.00 110 120 348.00 340.00 209 121 354.00 322.00 120 121 BASIN 200 200 210 358.00 355.00 210 230 355.00 350.00 1248ds.xls LENGTH FEET 160.00 270.00 420.00 110.00 290.00 100-YEAR STORM Ti Tc INTENSITY SUB. c MINUTES MINUTES (IN/HR) (ACRES) PRE-DEVELOPED CONDITION 1.13 10.00 4.30 0.30 0.45 2.25 12.25 5.00 2.50 0.45 2.80 2.20 10.00 4.50 0.40 0.90 12.25 3.90 3.20 PRE-DEVELOPED CONDITION 1.17 10.00 4.10 0.20 0.45 2.93 12.93 3.80 1.40 0.45 1.60 CA TOTAL CA 0.14 0.14 1.13 1.26 0.36 0.36 1.62 0.09 0.09 0.63 0.72 Q (CFS) 0.58 6.30 6.30 1.62 6.32 0.37 2.74 2.74 SHEET 2 OF 2 11/22/2013 REMARKS Initial Area Street Flow Confluence Initial Area Hydrology Results 1 00 -Year Storm PRE-DEVELOPED POST-DEVELOPED CONDITION CONDITION AREA DISCHARGE AREA DISCHARGE (ACRES) (CFS) (ACRES) (CFS) BASIN 100 3.2 6.32 3.48 5.19 BASIN 200 1.60 2.74 1.24 4.07 4.80 9.06 4.72 9.26 OFF SITE CT 99 0.00 0.00 1.40 4.16 OFF SITE AVENA CT. 0.40 1.20 0.40 1.20 cfs (cubic feet per second) 1248ds.xls -5 - TENTATIVE MAP TRACT NO. CT CITY OF CARLSBAD ' ' ' ' BA ' ' ' : ' : ' ' ' ' ' ' ' ' .--------J _____ J ENGINEER OF WORK R. BHATIA CtVCOiol & ASSOCfA T£S 5850 06£RLIH DRM', SUITE JSO SN< DIEGO, CA 92121 (858) 658-94-00 05-18 L .....>-\ I I I I I I DITCH LEGEND SUB01V1S10N I!Ol.OIDARY---------------- LOT BOUNDARY------------------------ OUST. STORti DRAIN AND CLENoiOUT ---- EXISTING CONT~-------------------- PROPOS£0 CONTOUR-------------------- STREET ELEVATION--------------------- STREET GRH>E ------------------------ FENCE LNE ------------------------- RET~NNG WALL----------------------- BASIH 80\JNDARY------------------------- SUB AREA BOUNDARY-------------------- NOD£ NUMSER ------------------------ SUB /IR.EA ACREAGE--------------------- DIRECTION OF FLOW----------------------- I'll I --J50--__ ,. __ 100 YR STORM PEAK DISCHARGE----------0100 • 2.0 Cf'S PRE ·DEVELOPMENT BASIN 100 0.3AC 2.5AC 2.8AC 100• 2.66 CFS TC•12.93 MIN A•1.6 AC BASIN 200 0.2AC 1.4AC 1.6AC HYDROLOGY MAP PRE-DEVELOPMENT CONDITION eXHI81T 1 ' --- TENTATIVE MAP TRACT NO. CT CITY OF CARLSBAD SEASCAPE ....... '• I ,, ENGINEER OF WORK R. BHATIA CIVCOIJ It ASSOCIATES 6540 LUSK BLVD., SUITE CIJS SN< DECO, CA 92121 (858! 658-9400 I IJ! , :: J: ----r EXISTJIIG M.ETS Y\t<, 05-18 LEGEND SUIIOMSION BOUNDARY---------------- LOT BOlHlARY------------------------ EXlST. STOfU' DRAIN N«> CLENK»UT--·- EXISTING CONTOI..R-------------------- PROPOS£0 CONTOUR-------------------- STREET ELEVATION--------------------- STREET GRADE ------------------------ FENCE liNE -------------·------------ RETM..c; WALL----------------------- BASIN BOlti>MY------------------------- SUB AREA BOlHlARY-------------------- NOO£ NUIIBER ------------------------ SUB AREA .ocREAGE--------------------- OIIECTION OF FLOW----------------------- 100 YR STOMA PEAK DISCHARGE---------- TIME OF CONCENTRATION---------------- PRE -DEVELOPMENT __ ,_ -----~ ---- 0100 • 2.0 crs TC • 5.5 ..... BASIN 100 BASIN 200 3.20 AC 1.60 AC POST-DEVELOPMENT BASIN 100 3.48 AC BASIN 200 1.24 AC ,~'y,~ROLOGY MAP POST-DEVELOPMENT CONDITION EXHIBIT 2 4.3 EXISTING CAPACITY AT BLACK RAIL ROAD The existing Storm Drain System on Black Rail Road was constructed per Improvement Plan 335-5. The storm drain carrying flow from Seascape will connect to this existing system at approx. Sta 14+90 on Black Rail Road. Exhibit 3 shows the connection point Node 511 as well as all the areas upstream of the connection. In order to evaluate the capacity of the existing pipe all upstream contributing areas, time of concentration and the resulting flows were computed based on existing Hydrology Studies for those areas as follows: Area Tract No. Contributing Area Encantada CT 98-17 1.13Ac Tabata CT 00-13 2.53Ac Yammamoto CT 04-01 2.70Ac Aviara Pointe CT 99-10 3.40Ac Aviara Pointe CT 99-10 1.20Ac Seascape CT 05-18 4.17 Ac Black Rail Road 1.90Ac All the flows from properties to the North of the site enters the Storm Drain System via pipes and inlets located at sta 17+72 on Black Rail Road. However, the runoff generated from Seascape will flow into the existing storm drain at Sta 14+90 via a proposed inlet and 24" pipe. Total flow at Node 511 (see Exhibit 3) is calculated per the attached worksheet. Total flow from Node 511 to 512 for Post Development Condition based on 1 00-yrfrequency is 27.46 cfs. The capacity of the existing 24" RCP@ 5.50% is 53.05 cfs. The proposed 1 00-yr discharge results in a depth of flow in the pipe of 1.13 ft. 4.4 INLET DESIGN AT AVENA COURT EAST The inlet design and sizing is based on the following equation from Canty of San Diego Drainage design Manual: Q/L = 0.7 (a+ y}312 Q = interception capacity of the curb inlet (ft3/s ); y =depth of flow approaching the curb inlet (ft); a= depth of depression of curb at inlet (ft); -6- CIVCOM 5.0 CONCLUSIONS & RECOMMENDATIONS Based on the above calculations and analysis it is concluded that the downstream existing pipe can accommodate the proposed discharge. Therefore, the development of this site does not have any adverse effect on the existing Storm Drain System. The existing system can adequately handle the flow from this development. CJVCOM CIVCOM a A880CIAT1!8 6540 LUSK BL\10, SulT• Ct35 San OleQo, Coll1'or-nlo 92121 (8581 658-9400 Faxo 11581 658-9420 CT 97-20 512 TENTATIVE MAP TRACT NO. CT 05-18 BLACK RAIL ROAD CITY OF CARLSBAD BLACK RAIL ROAD I rsooj ~/ ) CT 98-1 CT 00-13 ---l====tl==::t CT 04-01 GRAPHIC SCAL£ 1"• 80' - POST DEVELOPMENT CONDITION EXHIBIT 3 PROJECT: SEASCAPE JOB No.: 1269 FROM TO CONTRIBUTING NODE NODE AREA 500 501 BLACK RAIL ROAD 501 506 BLACK RAIL ROAD 506 508 BLACK RAIL ROAD 500 502 BLACK RAIL ROAD CT98-17 502 CT98-17 502 507 BLACK RAIL ROAD 503 507 CT 00-13 502 507 CT 04-01 502 507 CT 99-10 502 507 504 505 CT 04-01 CT99-10 505 CT 99-10 505 508 508 511 CT99-10 509 CT 99-10 509 510 CT 05-18 509 510 CT05-18 510 CT 05-18 510 511 511 512 NODES SHOWN ON EXHIBIT 3 BLKRAILDS.xls Ti MIN Tc BLACK RAIL ROAD 100-YEAR STORM INTENSITY SUB. MINUTES (IN/HR) (ACRES) c POST-DEVELOPED CONDITION -100 YEAR 0.10 0.80 0.89 0.80 0.10 0.80 10.00 1.13 0.49 0.89 0.80 10.00 2.53 0.49 0.67 0.49 0.60 0.49 8.20 18.20 3.10 2.03 0.49 2.80 0.49 0.30 18.50 3.00 12.00 3.30 1.52 0.49 4.20 16.20 3.30 1.57 0.49 16.20 3.30 3.09 0.49 10.00 2.60 0.49 16.20 3.30 0.19 18.69 3.00 CA TOTAL CA 0.08 0.08 0.71 0.79 0.79 0.79 0.08 0.08 0.55 0.55 0.71 0.71 1.24 1.24 0.33 0.33 0.29 0.29 3.21 0.99 0.99 1.37 1.37 2.37 2.37 6.37 0.74 0.74 0.77 0.77 1.51 1.51 1.27 1.27 2.79 2.79 9.15 Q (CFS) 9.94 - 19.10 2.46 2.54 5.00 9.20 27.46 SHEET 1 OF 2 11/22/2013 REMARKS Street Flow Street Flow Pipe Flow Street Flow Overland Flow Gutter Flow Street Flow Street Flow Street Flow Confluence Pipe Flow Pipe Flow Pipe Flow Confluence Street Flow Street Flow Street Flow Pipe Flow Pipe Flow PROJECT: SEASCAPE JOB NO.: 1269 FROM TO CONTRIBUTING NODE NODE AREA 500 501 BLACK RAIL ROAD 501 506 BLACK RAIL ROAD 506 508 BLACK RAIL ROAD 500 502 BLACK RAIL ROAD .J T98-1 502 CT98-17 502 507 BLACK RAIL ROAD 503 507 CT 00-13 502 507 CT 04-01 502 507 CT 99-10 502 507 504 505 CT 04-01 ~T99-1 505 CT 99-10 505 508 508 511 ~ T99-1 509 CT 99-10 509 510 CT 05-18 ~T05-1 510 CT 05-18 510 511 511 512 NODES SHOWN ON EXHIBIT 3 BLKRAI LDS .xis Ti Tc MIN MINUTEE BLACK RAIL ROAD 1 0 -YEAR STORM INTENSITY SUB. c (IN/HR) (ACRES) POST -DEVELOPED CONDITION -10 YEAR 0.10 0.80 0.89 0.80 0.10 0.80 10.00 1.13 0.49 0.89 0.80 10.00 2.53 0.49 0.67 0.49 0.60 0.49 8.20 18.20 1.50 2.03 0.49 2.80 0.49 0.30 18.50 1.40 12.00 1.52 0.49 4.20 16.20 1.57 0.49 10.00 2.60 0.49 16.20 1.80 0.19 18.69 1.40 CA TOTAL CA 0.08 0.08 0.71 0.79 0.79 0.79 0.08 0.08 0.55 0.55 0.71 0.71 1.24 1.24 0.33 0.33 0.29 0.29 3.21 0.99 0.99 1.37 1.37 2.37 2.37 6.37 0.74 0.74 0.77 0.77 1.27 1.27 2.79 2.79 9.15 Q (CFS) 4.81 - 8.91 5.02 12.82 REMARKS Street Flow Street Flow Pipe Flow Street Flow Overland Flow Gutter Flow Street Flow Street Flow Street Flow Confluence Pipe Flow Pipe Flow Pipe Flow Confluence Street Flow Street Flow Street Flow Pipe Flow Pipe Flow SHEET 2 OF 2 11/22/2013 Project Description Project File Worksheet Flow Element Method Solve For Input Data CAPACITY OF EXIST PIPE IN bla Worksheet for Circular Channel c:\haestad\fmw\seascape. fm2 EXIST PIPE CAPACITY Circular Channel Manning's Formula Full Flow Capacity Mannings Coefficient Channel Slope Diameter 0.013 0.055000 fUft 24.00 in Results Depth 24.0 in Discharge 53.05 cfs Flow Area 3.14 fF Wetted Perimeter 6.28 ft Top Width 0.00 ft Critical Depth 1.98 ft Percent Full 100.00 Critical Slope 0.051097 fUft Velocity 16.89 fUs Velocity Head 4.43 ft Specific Energy FULL ft Froude Number FULL Maximum Discharge 57.07 cfs Full Flow Capacity 53.05 cfs Full Flow Slope 0.055000 fUft 11/22/13 01 :44:41 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 FtowMaster v5.13 Page 1 of 1 Project Description Project File Worksheet Flow Element Method Solve For Section Data Cross Section Cross Section for Circular Channel c:\haestad\fmw\seascape. fm2 EXIST PIPE CAPACITY Circular Channel Manning's Formula Channel Depth Mannings Coefficient Channel Slope Depth 0.013 0.055000 tUft 1.02 ft Diameter Discharge 24.00 27.46 in cfs 24.00 in ~~ H 1 NTS 11/22/13 01:39:02 PM Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 (203) 755-1666 FlowMaster v5.13 Page 1 of 1 Detailed Report for Pipe SD-1 @ Avena Court lEast Section Material: Concrete Section Shape: Circular Section Size: 18 inch Number Sections: 1 Description Discharge Mannings Coefficient Length Constructed Slope Upstream Flow Time Pipe Flow Time System Flow Time Grade Elevations 6.37 cfs 0.013 61 .00 ft 0.013279 ftlft 15.50 min 0.17 min 15.67 min Location Invert Ground Crown (ft) (ft) Upstream 319.00 323.10 Downstream 318.19 323.00 Messages: Profile: Steep supercritical frontwater profile (S2). Profile: Critical depth assumed upstream. (ft) 320.50 319.69 Description Capacity Hydraulic Drop Energy Slope Upstream Velocity Average Velocity Downstream Velocity Cover Depth (ft) (ft) 2.60 0.98 3.31 0.78 Violation: does not meet minimum cover constraint at downstream end. Project Title: seascape c:\haestad\stmc\project1 .stm Civcom & Associates HGL (ft) 12.10 cfs 1.01 ft 0.011378 ftlft 5.23 ftls 6.07 ftls 6.91 ftls EGL (ft) 319.98 320.40 318.97 319.71 Project Engineer: CIVCOM & ASSOCIATES StormCAD v1 .0 08/22/12 08:46:37 AM © Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA (203) 755-1666 Page 1 of 1 REFERENCES 1. Standards for Design and Construction of Public Works Improvements in the City of Carlsbad. 2. San Diego County Hydrology M-anual, 2003 3. Hydrology Study for CT 04-01 in the City of Carlsbad, pepared by MLB Engineering, February 27, 2006 4. Drainage StudyforTabata Property CT 00-13, prepared by O'Day Consultants, Inc. May9, 2002 5. Hydrology Map for Hadley Property CT 98-17 in the City of Carlsbad Prepared by MLB. 5. Hydrology Map for Moore Property CT 98-17 in the City of Carlsbad 7. Drainage Study for Aviara Pointe CT 99-10, prepared by Civcom & Associates June 27,2002 CIVCOM APPENDICES CIVCOM 5 B 15 .20 40 Minutes Duration EQUATION = 7.44 P6 0-0.645 Intensity (inlhr) 6-Hour Precipitation (in) Duration (min) 2 3 Hours 4 2.5 2.0 1.5 1 0 5 6 Intensity-Duration Design Chart -Template Directions for Application: ('I) 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 crf 45% to 65% of the 24 hr precipitation {not applicaple to Desert}. (3) Plot 6 hr precipitation on the right side oi the chart. (4) Draw a line through the point parallel to the plotted lines. (5) This line is the Intensity-duration curve for the location being analyzed. Application Form: (a) Selected frequency~ year (b) r6 = __LL in .. p24 = _3j__ .;s = 4 ~ %(2> ~ 24 (c) Adjusted p5!2l = I' in. (d) !x = ___ min. (a) I= ___ in.!hr. Note: This chart replaces the Intensity-Duration-Frequency curves used since 1965 . . ,iPS 1~----~--~~.; :·-;·-3.5 4 ~---;--~~----·;-~ Duration . i * I ! I I ! , I I l ., 5 2.53 •3.9.5i 5.27 6.59 ' 7.90 9.22 10.54!! 1.86 .1~.17' 14.49 15.8~1' :; -z.~~-?. ji-1? .• ,2~: 5~3( 1l.~s.:? ·~~ s.4s : 9.54 . 1oso, 11.ss, 12.12 I 10 Lo_~_,2._53:3 :37 ~.21 .~ 5.05, 5.90. ~:r4: 758 8.42_; ~p 1Q.I ~~ ! 15 13!> ,1.9~,2,59 ;.3?.:!i3·89~4.54, 5.).9.. 5 .. 84 6.~9 , ?:13 __ ~7.:?.8 1' 20 1.08 . 162! 2 15:269: :!.23;,3.77 . ·131 .. 4 .. 85. S:J~ . _?.9:1 , 64?. 25 0.93 '1.40· 1.87 ' 2.33. 2.80' 3.27 3.73 . 4.20 4.67 5. t3 5.60 .:;J! d.~ :.~..;; ~ G~~-:~:~~;~2-~·~_:::s-D; 3.32 ! 3.7~ ~ ~-~·. :-~~ · ~;~ f 4~. o.69 , 1 o3: 1 38 , 1.'2. 2.01 , 2 41 : 2.76 . 3.lo •• 1.4!>., ., . .~, • ~.'"I ~~ o.oo ;o.~o1 u?, 1.~9 . 1.J9 ,_2.o~.: 2.~9. .. 2o9 · 2.!~. ~.zs j .:J.~s 1 oO 0.53 0 80, l.Oo 1.33 1.59 1 So 2.12 2.39 2.<>=> 2.9?. : 3.18 1 . 9Lo::H j-oai [ o,s2 j 1.02 · 1231143. 1 s~-.. 1.84 ;.· 2,04 : 2.:25 i 2 4sj 120 0.34 051 O.Sil iO.BS ,I.02 119· 1-36 • 1.53 , !.70 1.87 2.04 150 .. 0.29 ).44;0.59 j 0.13:o.as •. 1.03' ua : 132 :1.47 : 1,62 : 1.761 1_~Q g,2s.;o.~n;o,.52 [0.6S j0.78,0.91 ' 1.0-t . LIB ' I.Jl ; 1.44 J57 24() 0.22 ·o.33;0.43 ' 0.54 ,0.65. 0.76 O.B7 , 0.98 ; 1.08 . 1.19 ' 130 3oo o:i9 ;o:2S:_o,~~~o 4i ;o.50: o.aa : o.1s 1 o.es · o,94 ._~o3 : u J 360 0.1! '0.25; 0.33 0.42 0.50, 0.58 0:?1 __ 0.75 0.84 0.92 i.OO FIGURE 3-1 2.0 O'l ± :; 0 0 ~ .c: 1) -;, Ol Cil .;;; 0 .~1.0 6.0 -g: ;o.9 (if 5.5 "" 0 ·~o.e 5.0 :J *0.7 4.5 5 0 4.0 '::J' (0 0.6 3.5 ~ 0.5 3.0 0.4 2.5 2.0 6 7 8 9 10 15 20 30 40 so 2 3 4 5 6 Minutes Hours Duration lntensity·Duration Design Chart· Template ------- Directions for Application: (1) From precipitation maps determine 6 hr and 24 hr amoLJnts for the selected frequency. These ffi8PS are included in the County Hydrology Manual p o. 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% lo 65% of the 24 hr precipitation (not applicaple to Desert). (3) Plot 6 hr precipitation on the right side of the chart. (4) Draw a line through the point parallel to the plotted lines. (5) This line is the intensity-duration curve for the location being analyzed. Application Fonn: (a) Selected frequency _ 10-0 ye<u· (b)P6 = 2:6 in.,P24 = l.i·f; ~= 6f!1' o;o!2l ----·p24 -- (c) Adjusted P6<2> = Z· ~ in . (d) lx = ___ min. (e) I = __ in./hr. Note: This chart replaces the Intensity-Duration-Frequency curves used since 1965. Ps 1 -, ·~ 1.s : 2 • ?..5 ; 3 is i 4 4.s : s 1 s:s r s Duration ) I : i I ;· I i ! I .' I : I .j ! I ' t ----~ -~ 3-~_3 .1:! 9~. ~.27 . 6.?9 1 !·9~! 9 2?! 10.?4. 11.86_; 13 ! 'l 14A~ 1,~._8-~ . _ 7 3.J.?..te,!~i ~?2l.S,3?.'g,~§i!Bi ~·:!8_~_~!)4 i tO_!lOI IL_?Sp 27? 10 1 sa , 2.53: 3..37 : 4.2t Is os1s.oo. a.1-1 7.5s , 8.42 I 9.27 , 10.11 1s 13o l 1.9s1 2.59i3.2>~i369 i4.5,jf 5.19 ; 5.84 !"6A9 17.t3 l 7.7li 20 "t:Oil ;,.62;2.t51'2.69 j :lh~s77; 4.31"i ~:s5i"S.3!f! 5:93T6.46 25, .9 ila ·; 1.40: l.~-!! :?~~ifi ? 66,~ ?~: ~.~a : ~-?0 ['4.67 r 5.13"J5.6o 3.9 _P:~3 ~-~;~~j ~·~?.1 .. ~·~? -~_2.~~-i-'?·~~~.? .~:?_t ~~?-~--~--~·lfi t ~t:;s i. ~~ .~~ Y·~~ j 1q3\ L:Ji!j 1.72 !29?! ?4! )2.7~) 3,!!J l 3.~5J:!-?9 ! .~·l:J . s~ _o 6!! : o.9o; 1,1 ~-!1-~9 L 1J 9; 2.~~ 1 2.39 : _2.§~ ; 2 .. ~~ j ~~~ -1 a.;,~ G~ __ q,s3 ·O ~o; 1 9~ 1 . 1.33 ~ 1.59 ~ 1.~~~ 2. !2 ; 2.3~ ! ?.ss 2 ~2 ~ ~~ 90 041 •061:082 1 02 ;123; 1.431 163 ; 1.84 :2.04 '22!> I iH5 ·--·ho ·o-3·1 lo .. si;o.s8 ' o.as.~ i.o2; 1 19: t.s~ \ 1 53 ;·1.10 j 1.a1 2.~4 .!S.~ .~·~9.;0.44 !059l 6.73 )988 1 1·0~l 1 !ll : 1.32 i 1.47 1 1.62 !1?§ 1_8~ !J 't6 !0!3.~l~52i O.G5 :0.78 )~.9! 1.0:-1 J 1.18 ! 1.31. 1 .4~ 1 1.~7 .?~0. .0.2.?_;q.3*:~3i.!J·~: 0.65; <?,?~J O.B7 ! 0._!1~ j L~ i 1 .. 1~ j 13~ _,300. -~·I9 i q2~~-~,3~:9··rr.f q,?~~o.~e;o.75 :.9,as : Q.?~ i !,0~_!1,!3 3so 0.11 lo.2sJo,JJi 0.42 ;o,so ;o.ss. o.s7 L_0.75 1 o.s4 i o.92 L .. !.:.£0 ATTACHM ENT B HYDROLOGY STUDY CT 05~18 Table 3-1 HYDROLOGY STUDY CT 05-·18 RUNOFF COEFFlClENTS FOR URBAN AREAS --------------------------------,---------------------------------- Land Use Runoff Coefficient "C" Soil Ty Je NRCS Elements Count Elements % IMl,ER. A B c D Undisturbed N<ltur<ll Terrnin (NC!tural) Permanent Open Space 0* 0.20 0.25 0.30 0.35 Low Density Residential (LDR) Residential, 1.0 DU/A or less 10 0.27 O.J2 0.36 0.<11 Low Density Residential (LDR) Residential, 2.0 DU/A or less 20 0.34 0.38 0.42 0.46 Low Density Rcsidentinl (LDR) Rcsi~ential, 2.9 DUIA or less 25 0.38 0.41 0.45 0.49 Medium Density Residential (MDR) Residenti11l, 4.3 DUIA or less 30 0.41 0.45 f).48 0.52 Medium Density Residential (MDR) ResiclentinL 7.3 DU/A or less 40 0.48 0.51 0.54 0.57 Medium Density Residential (MDR) Residential, 10.9 DUiA or less d~ .) 0.52 0.54 0.57 0.60 Medium Density Residentifll (MDR) Residential, 14.5 DU/A or less 50 0.55 0.58 0.60 0.63 High Density Residential (HDR) Re-sidential, 24.0 DUIA or less 65 0.66 0.67 0.69 0.71 High Density Residential (HDR) Residential, 43.0 DU/A or Jess so 0.76 0.77 0.78 0.79 Commercial/lndustri;~l (N . Com) Neighborhood Commercial so 0.7fi 0.77 0.78 lU9 Commercial/lndustrial (G. Com) General Commercial &5 0.30 0.80 0.8 1 0.82 Commercial/hidustrial (O.P. Com) Office Pro fcssionaliCommercial 90 0.83 0.84 0.84 O.ll5 Commercial/Industrial (Limited 1.) Limited lndm:trial 90 0.83 0.84 0.84 0.85 Cornmercial/1 ndustrial (Genera 11.) General Industrial 95 0.87 0.87 0.87 0.87 ~The V!!hJ·-:;s ~5S0[:1!!!~d '-~'!!!-: IJ~·S !=::p~:-·;!cu~ :;'!;.:_y t.~ o..:;:..ed ~c,;-~;teet ccd~t.•!it~~C.fi vf th~ :ur:~!fr cL•t::fG:·.:c·.ni ;:,s rie~:cr!bcd in Section 3. i .2 {_represenltng the lJervious runoff coefficient, Cp, for the soil type), or for areas th<~t will re~na·in undisturbed in perpetuiiy. Justification must be given that the area will remain nat11ral forever (e.g., the area is located in Cleveland N<~tional Forest). DU/A =dwelling units per acre NRCS =National Resources Conservation Service ATTACHMENT C Element* Natural LDR LDR LDR MDR lviDR :tviDR MDR HDR HDR N.Com G. Com O.P./Com Limited I. General I. Table 3-2 HYDROLOGY STUDY CT 05-18 MAXIMUM OVERLAND FLOW LENGTH (LM) & INITIAL TIME OF CONCENTRATIO:~ (Ti) DU/ .5% 1% 2% 3% 5% 10% Acre LM Ti LM Ti LM Ti LM Ti LM Ti LM Ti 50 13.2 70 12.5 85 10 .9 100 10.3 100 8.7 100 6.9 1 50 12.2 70 11.5 85 10.0 /100 9.5 100 8.0 100 6.4 2 50 11.3 70 10.5 85 9.2 100 8.8 100 7.4 100 5.8 2.9 50 110.7 70 10.0 85 8.8 95 8.1 100 7.0 100 5.6 4.3 50 10.2 70 9.6 80 8.1 95 7.8 :tOO 6.7 /IOO 5.3 7.3 50 9.2 65 8.4 80 7.4 95 7.0 100 6.0 100 4.8 10.9 50 8.7 65 7.9 80 6.9 I 90 6.4 !00 5.7 100 4.5 14.5 50 8.2 65 7.4 80 6.5 90 6.0 100 5.4 100 4.3 24 50 6.7 65 6.1 75 5.1 90 4.9 95 4.3 100 3.5 tl."' ,.J 50 5.3 65 4.7 75 4.0 85 3.8 95 3.4 100 2.7 50 5.3 60 4.5 75 4.0 85 3.8 95 3.4 100 2.7 so I 4.7 60 4.1 75 3.6 85 3.4 90 2.9 100 2.4 50 4.2 60 3.7 70 3.1 80 2.9 90 2.6 100 2.2 so 4.2 60 3.7 70 3.1 80 2.9 I 90 2.6 100 2.2 I 50 3.7 60 3.2 10 I 2.7 80 2.6 90 2.3 100 1.9 *See Table 3-1 for more detailed description ATTACHMENT C2 .6.E I Feet Lsooo I Tc Tc L .6.E = :: = EQUATION c~~3Y.385 Time of concentration (hours) Watercourse Distance (mile s) Change in elevation along effective slope lin~ (See Figure 3-S)(feet) .6.E SOURCE: California Division oi Highways (1941) and Kirpich (1940) L Miles Feet 4000 '\. . 3000 0.5 '\. 2000 1800 i600 1400 1200 1000 900 800 700 600 500 400 300 20{) L '\. Nomograph for Determination of Tc "'"l""'" 4 240 3 iBO 2 '\. ' " Tc Time of Concentration (Tc) or Travel Time (Tt) for Natuml Watersheds FIGURE L3-4 I 513 I I'P22.n At:; - Q100-44.40 ~ TC•18.7 WI. I / / I CIVCOM a ASSOCIATES 6540 LUSK BLVD. Sui-te Cl35 San Diego, California 92121 (858) 658-9400 Fax: (858) 658-9420 \ I f CT 97-20 -~'\ /<::_1512 I ~~ r r r r ' r / --. / / / ' / ,/ / / ' / r r r ' / ' ' -~ ----~ --------------·-- t v ' ' ' ~ r / / / / / / / TENTATIVE MAP TRACT NO. CT 05-18 ' so 40 0 80 160 -- GRAPHIC SCALE 1"= 80' ·BLACK CITY OF 240 RAIL ROAD CARLSBAD CT 04-01 . CT 00-1.3 / / CT 98·1~ I ~-----1 ' I ··. ' 1----------.j ' i r------.j POST DEVELOPMENT EXHIBIT 3 l:j 11 1 I . i! .1 I : l ' I. - l t I VICINITY 11' f i . CIVCOM 6 A880CIATE8 5850 Oberlin Drtve. Sutte 350 Son Diego, Calt'fornta 92121 <8581 658-9400 Fax. <858) 658-9420 CAMINO REAl. ( 0.81AC) \ \ \ l I f ! I i TENTATIVE MAP TRACT NO. CT ' r' j \ ' ill \ l l i ! I \ I I i CITY OF CARLSBAD ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' ' 100 ( 0.81AC) \ "\ \ ,_ i i ' ' ' ' ' ' ' ' SEASCAPE ' ' ' ' ' ' ' ' ' I ' ~ f' 1 EXISTING f,. RIDGE liNE d o.15AC) // ' I [, \ ' \ ~~-- 1 I '' ' \ \ \ · £NGIN££R OF WORK R. BHATIA CIVCOM & ASSOCIATeS 6540 LUSK BLVD., SUIT£ C1.J5 SAN DIEGO, CA 92121 (858) 658-9400 ' ' ' ' ' (o.53AC) ' ' ' ' ' _, ' ' ' ' ' ' ' ' ' ' ------------------------------ 05-18 LEGEND ' ' ., ' ' ' 'i ' \ l ' ' ' ' ' ' ' ' SUBOlVISION BOUNDARY---------------- LOT BOUNDARY------------------------ EXIST. STORM DRAIN AND CLEANOUT ---- EXISTING CONTOUR-------------------- PROPOSED CONTOUR-------------------- STREET ELEVATION--------------------- STREET GRADE ------------------------ FENCE LINE -----------------------.,-- RETAINING WALL----------------------- BASIN BOUNDARY------------------------- SUB AREA BOUNDARY-------------------- NODE NUMBER ------------------------ SUB AREA ACREAGE--------------------- DIRECTION OF FLOW----------------------- -··-·---··- -350- 2.001. ----- 022] ( 0.2 AC) 100 YR STORM PEAK DISCHARGE----------Q100 • 2.0 CFS TIME OF CONCENTRATION·---------------TC a 5.5 MIN. ' ' PRE -DEVELOPM.ENT BASIN 100 3.20 AC BASIN 200 1.60 AC POST-DEVELOPMENT BASIN 100 3.48 AC ' ' ' BASIN 200 1.24 AC HV,DROLOGY MAP ' POST-DEVELOPMENT CONDITION EXHIBIT 2 m 0 .. -"' 6 '-.-> ·~ / L-----------------------------------------------------------------------------------~--------------------------------------------------~--------------------------------------------------------------_ji~ . ( ' ' ' ' ' ' ' ' I 19 .... I I I I I I I I I I I .!&4 CIVCOM & A880CIA TE8 5850 Oberlin Drive. Suite 350 I sen Diego. Call'fornra 92121 (8!581 658-9400 Faxol858) 658-9420 ···--.----- TENTATIVE MAP TRACT NO. CT CITY OF CARLSBAD ' ' ' ' ' ' ' ' ' ' DRAINAGE:-,SW ALE ' ' ' \ ' ' ' ' __....:-7·- ._ ___ l I I I I 1 I I 1 1 I I I 1 I I I I I I I . DRAINAGE I -~120 __ , I I I I I I I I ~ ( 2.5 AC) I . ----------~-, ; I I I I I I BA I I I I I I I I I I I I I I 1 I _;;__T------r-..J "" I \' l ~ II : ~ II : i t ' ;' ,( I I I I II ' -'---------~e>:: ' ' ' ' .... ' ' ' ' ' IN', I I I I I I I , ___ _ - I I I I.-J=s=s-=.o--.1 l EX.HOOS£ I I I :J__ -'=:I 1 ; t I I Ell HflltSE I J I 365.0 I : 1L I I L__ --j L---.3---...C-- ', 0 -----, r-...-------. ~ I '' I I I I ' I I I I 'I I I I I I I I I 1 ,;,i ' I I § '.J I (8 I I <It 1, I fii I I ·"' ' I if 1 A~ I ' I 1 ~<;> I ', ~ ! I I I 'I ft I L-~""'-L·· l .. 'f~, : -~-L-...---- ' .... ' ENGINEER OF WORK R. BHATIA CIVCOM St ASSOCIA TE:S I • I • I • L I I 5850 OBERLIN DRIVE, SUIT£ JSO SAN DIEGO, CA 92121 (858) 658•9400 ' ' ' ' ' . ' ' ' ' ' ' ' ' CAMINO REAL 05-18 ' ' ' ~-~ I I I I I I --1 I I ' I I I I I I I I I I I I I I I I __ ..J .. EXIST BROW DITCH LEGEND SUBDIVISION BOUNDARY---------------- LOT BOUNDARY------------------------ EXIST. STORM DRAIN AND CLEANOUT---- EXISTING CONTOUR-------------------- PROPOSED CONTOUR-------------------- STREET ELEVATION--------------------- STREET GRADE ------------------------ FENCE LINE ------------------------- RETAINING WALL----------------------- BASIN BOUNDARY------------------------- -··-·---··- ==t2E===== ...---350--..-...... -350- 2.00X ....... o....--"~-~-~~--·-' -~--~-·-··-. .... . .. ,.. .. ... SUB AREA BOUNDARY------------------------- NODE NUMBER ------------------------(!Q£]. SUB AREA ACREAGE---------------------( 0.2 AC) DIRECTION OF ELOW----------------------- 100 YR STORM PEAK DISCHARGE----------Q1DO • 2.0 CFS TIME OF CONCENTRATION.----------------TC .. 5.5 MIN. PRE -DEVELOPMENT BASIN 100 0.3AC 2.5AC 2.8AC BASIN 200 0.2AC .1.4AC 1.6AC HYDROLOGY MAP PRE-DEVE.LOPMENT CONDITION EXHIBIT f "' c. "' '-' tn "' "' "'I m CD (\J ... I E' ~ .:· ,._ ' ·- 1 i t· L_ __________ ~-----------------------~--------------------------------------------------------------~-----------------------------------------------~