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Home My WebLink AboutPD 2020-0008; CHURCH RESIDENCE; DRAINAGE STUDY; 2020-08-18 (2)DRAINAGE STUDY FOR CHURCH RESIDENCE ADAMS STREET DWG 524-6A GR2020-015 PD2020-008 APN: 206-200-04 PREPARED BY: SOWARDS AND BROWN ENGINEERING, INC. CONSULTING ENGINEERS 2187 NEWCASTLE AVENUE, STE 103, CARDIFF, CA 92007 (760) 436-8500 18-045 8/18/20 SOWARDS AND BROWN ENGINEERING 2187 NEWCASTLE AVENUE, STE 103 CARDIFF BY THE SEA, CALIFORNIA 92007 JOB: 18-045 CHURCH RESIDENCE DATE: 8/18/2020 SHEET: 1 1. 2. 3. 4. 5. 6. 1. 2. 3. 4. 5. DRAINAGE STUDY FOR: SITE SPECIFICS: A PORTION OF THE SITE WILL DRAIN NORTHEASTERLY AFTER DEVELOPMENT, DUE TO CITY REQUIREMENTS TO WIDEN ADAMS STREET AND ADD A SIDEWALK. THE BALANCE OF THE LOT WILL CONTINUE TO DRAIN SOUTHERLY TO THE LAGOON AFTER PROPOSED STORM WATER TREATMENT WITH DEVELOPMENT OF THE SITE. REFER TO THE ENCLOSED DRAINAGE MAPS FOR BASIN LOCATIONS AND AREAS THE SITE IS A 0.45 ACRE RESIDENTIAL LOT LOCATED IN CARLSBAD, SOUTH OF ADAMS STREET AND EXTENDS INTO AGUA HEDIONDA LAGOON TO THE SOUTH. THE SITE IS CURRENTLY VACANT AND IS BORDERED BY VACANT LOTS TO THE NORTH. THE LOT TO THE WEST IS A PROPOSED SINGLE FAMILY RESIDENCE AND THERE IS AN EXISTING SINGLE FAMILY RESIDENCE TO THE EAST. THE ENTIRE SITE CURRENTLY DRAINS SOUTHERNLY TO THE LAGOON WITH NOMINAL OFFSITE DRAINAGE FROM THE WEST. THERE IS NO CROSS‐LOT DRAINAGE TO THE LOT TO THE EAST DUE TO A WALL AT THE COMMON PROPERTY LINE. A SINGLE FAMILY RESIDENCE WILL BE BUILT ON THE SITE AND BIOFILTRATION BASINS WILL BE INCLUDED FOR WATER TREATMENT. AN UNDERGROUND VAULT PROVIDES MITIGATION OF THE FLOW FROM THE BIOFILTRATION BASINS. THE WESTERLY 75 FEET OF THE EASTERLY 225 FEET OF LOT 6 IN BLOCK 'D' OF BELLA VISTA, IN THE CITY OF CARLSBAD, COUNTY OF SAN DIEGO, STATE OF CALIFORNIA. ACCORDING TO MAP THEREOF NO. 2152. USE SAN DIEGO COUNTY HYDROLOGY MANUAL ‐ RATIONAL METHOD DESIGN FOR 100‐YEAR STORM USING THE COUNTY'S ISOPLUVIAL CHARTS AND INTENSITY‐DURATION FORMULA TO DETERMINE INTENSITIES (I100). SEE ATTACHED USE OVERLAND TIME OF FLOW FORMULA FROM FIGURE 3‐3 OR NATURAL WATERSHED NOMOGRAPH FROM FIGURE 3‐4 TO DETERMINE TIMES OF CONCENTRATION (TC). SEE ATTACHED RUNOFF COEFFICIENT BASED ON SOIL TYPE 'B' ACCORDING TO THE USDA WEB SOIL SURVEY WEBSITE AND TABLE 3‐1. RUNOFF COEFFICIENTS ARE WEIGHTED BASED ON THE AREAS OF THE INDIVIDUAL SURFACES. SEE ATTACHED CRITERIA: USE FIGURE 3‐1 TO DETERMINE THE ADJUSTED 6‐HOUR STORM RAINFALL AMOUNT APN: 206‐200‐04 SOWARDS AND BROWN ENGINEERING 2187 NEWCASTLE AVENUE, STE 103 CARDIFF BY THE SEA, CALIFORNIA 92007 JOB: 18-045 CHURCH RESIDENCE DATE: 8/18/2020 SHEET: 2 Basin A:Area : 19,660 ft2 →0.451 ac Soil Type 'B' , C = 0.25 ft2 Runoff Coefficient Area 19,660 C = 0.25 : Weighted Runoff Coefficient Ti = Initial Time of Concentration (min) D = 100 : flow length (ft) s = 27.50 : slope (%)Elev1:62.8 Elev2:35.3 Tt = Travel Time (min) L= 0.25 )√100 ³√27.5 173.43 Ti = 1.8 ( 1.1 ‐ Ti =5.07 min : flow length (ft)→0.033 miles ∆E = 33.0 : flow length (ft)Elev1:35.3 Elev2:2.26 (11.9 x 0.033 ³) 0.385 5.07 + 0.78 = 5.85 min Tt =33 Tt =0.013 hrs → Q100 =0.672 Pre‐Development Hydrology cfs Q100 = Peak Discharge (cfs) = 0.25 x 5.95 x 5.85 ‐0.645 I100 =5.95 in/hr I100 = Rainfall Intensity (in/hr) = 7.44 x 2.50 0.78 min Tc = Time of Concentration (min) = min I100 = P6 = 2.50 D = 5.85 x 0.45 ܫଵ଴଴ ൌ 7.44ܲ଺ܦି଴.଺ସହ ܶ௜ ൌ 1.8 1.1 െܥ ܦ ݏయ ܶ௧ ൌ 11.9ܮଷ ∆ܧ ଴.ଷ଼ହ ܶ௖ ൌ ܶ௜ ൅ ܶ௧ ܳଵ଴଴ ൌܥ ൈ ܫଵ଴଴ ൈܣ D D (-) D D SOWARDS AND BROWN ENGINEERING 2187 NEWCASTLE AVENUE, STE 103 CARDIFF BY THE SEA, CALIFORNIA 92007 JOB: 18-045 CHURCH RESIDENCE DATE: 8/18/2020 SHEET: 3 I100 = Rainfall Intensity (in/hr) P6 = 2.50 Q100 =0.13 ◦ By inspection, Tc < 5 min Tc = 5.0 Post‐Development Hydrology Basin 1:Area : This Basin drains northeasterly to Adams Street, then easterly along the northerly flowline of Adams Street 1,493 ft2 →0.034 ac D = 5.00 I100 =7.44 x 2.5 x 5.00 ‐0.645 Runoff Coefficient 0.25 ft2 Impervious Surfaces , C = 0.90 772 ft2 cfs I100 = min C= : Weighted Runoff Coefficient0.59 6.59 in/hr Q100 = Peak Discharge (cfs) = 0.59 x 6.59 x 0.03 Soil Type 'B' Tc = Time of Concentration (min) , C =721 min ܳଵ଴଴ ൌܥ ൈ ܫଵ଴଴ ൈܣ ܫଵ଴଴ ൌ 7.44ܲ଺ܦି଴.଺ସହ D SOWARDS AND BROWN ENGINEERING 2187 NEWCASTLE AVENUE, STE 103 CARDIFF BY THE SEA, CALIFORNIA 92007 JOB: 18-045 CHURCH RESIDENCE DATE: 8/18/2020 SHEET: 4 Q100 =0.18 cfs This Basin drains to Bioretention Basins where runoff is treated before being piped to an underground vault for flow mitigation, then sheet flows to the Agua Hedionda Lagoon I100 =6.59 in/hr Q100 = Peak Discharge (cfs) = 0.82 x 6.59 x 0.03 I100 = Rainfall Intensity (in/hr) P6 = 2.50 D = 5.00 I100 =7.44 x 2.5 x 5.00 ‐0.645 C = 0.82 : Weighted Runoff Coefficient Tc = Time of Concentration (min) ◦ By inspection, Tc < 5 min Tc = 5.0 min Impervious Surfaces , C = 0.90 1,235 ft2 , C = 0.25 185 ft2 min Basin 2:Area : 1,420 ft2 →0.033 ac Runoff Coefficient Soil Type 'B' ܳଵ଴଴ ൌܥ ൈ ܫଵ଴଴ ൈܣ ܫଵ଴଴ ൌ 7.44ܲ଺ܦି଴.଺ସହ D SOWARDS AND BROWN ENGINEERING 2187 NEWCASTLE AVENUE, STE 103 CARDIFF BY THE SEA, CALIFORNIA 92007 JOB: 18-045 CHURCH RESIDENCE DATE: 8/18/2020 SHEET: 5 Q100 =0.56 cfs This Basin drains to Bioretention Basins where runoff is treated before being piped to an underground vault for flow mitigation, then sheet flows to the Agua Hedionda Lagoon I100 =6.59 in/hr Q100 = Peak Discharge (cfs) = 0.79 x 6.59 x 0.11 D = 5.00 I100 =7.44 x 2.5 x 5.00 ‐0.645 Tc = Time of Concentration (min) ◦ By inspection, Tc < 5 min Tc = 5.0 min I100 = Rainfall Intensity (in/hr) P6 = 2.50 Impervious Surfaces , C = 0.90 3,934 ft2 C = 0.79 : Weighted Runoff Coefficient Runoff Coefficient Soil Type 'B' , C = 0.25 780 ft2 Basin 3:Area : 4,714 ft2 →0.108 ac ܳଵ଴଴ ൌܥ ൈ ܫଵ଴଴ ൈܣ ܫଵ଴଴ ൌ 7.44ܲ଺ܦି଴.଺ସହ D SOWARDS AND BROWN ENGINEERING 2187 NEWCASTLE AVENUE, STE 103 CARDIFF BY THE SEA, CALIFORNIA 92007 JOB: 18-045 CHURCH RESIDENCE DATE: 8/18/2020 SHEET: 6 Q100 =0.07 cfs This Basin drains to Bioretention Basins where runoff is treated before being piped to an underground vault for flow mitigation, then sheet flows to the Agua Hedionda Lagoon I100 =6.59 in/hr Q100 = Peak Discharge (cfs) = 0.90 x 6.59 x 0.01 D = 5.00 I100 =7.44 x 2.5 x 5.00 ‐0.645 Tc = Time of Concentration (min) ◦ By inspection, Tc < 5 min Tc = 5.0 min I100 = Rainfall Intensity (in/hr) P6 = 2.50 Impervious Surfaces , C = 0.90 551 ft2 C = 0.90 : Weighted Runoff Coefficient Runoff Coefficient Soil Type 'B' , C = 0.25 0 ft2 Basin 4:Area : 551 ft2 →0.013 ac ܳଵ଴଴ ൌܥ ൈ ܫଵ଴଴ ൈܣ ܫଵ଴଴ ൌ 7.44ܲ଺ܦି଴.଺ସହ D SOWARDS AND BROWN ENGINEERING 2187 NEWCASTLE AVENUE, STE 103 CARDIFF BY THE SEA, CALIFORNIA 92007 JOB: 18-045 CHURCH RESIDENCE DATE: 8/18/2020 SHEET: 7 Q100 =0.10 cfs I100 =6.59 in/hr Q100 = Peak Discharge (cfs) = 0.87 x 6.59 x 0.02 This Basin drains to Bioretention Basins where runoff is treated before being piped to an underground vault for flow mitigation, then sheet flows to the Agua Hedionda Lagoon D = 5.00 I100 =7.44 x 2.5 x 5.00 ‐0.645 Tc = Time of Concentration (min) ◦ By inspection, Tc < 5 min Tc = 5.0 min I100 = Rainfall Intensity (in/hr) P6 = 2.50 Impervious Surfaces , C = 0.90 753 ft2 C = 0.87 : Weighted Runoff Coefficient Runoff Coefficient Soil Type 'B' , C = 0.25 36 ft2 Basin 5:Area : 789 ft2 →0.018 ac min ܳଵ଴଴ ൌܥ ൈ ܫଵ଴଴ ൈܣ ܫଵ଴଴ ൌ 7.44ܲ଺ܦି଴.଺ସହ D SOWARDS AND BROWN ENGINEERING 2187 NEWCASTLE AVENUE, STE 103 CARDIFF BY THE SEA, CALIFORNIA 92007 JOB: 18-045 CHURCH RESIDENCE DATE: 8/18/2020 SHEET: 8 x 6.59 x 0.03 Q100 =0.19 cfs This Basin drains to Bioretention Basins where runoff is treated before being piped to an underground vault for flow mitigation, then sheet flows to the Agua Hedionda Lagoon Runoff Coefficient Impervious Surfaces , C = 0.90 Soil Type 'B' , C = 0.25 = 0.88 in/hr C = 0.88 : Weighted Runoff Coefficient Tc = Time of Concentration (min) ◦ By inspection, Tc < 5 min Tc = 5.0 min Q100 = Peak Discharge (cfs) P6 = 2.50 D = 5.00 1,377 ft2 I100 = Rainfall Intensity (in/hr) I100 =7.44 x 2.5 x 5.00 ‐0.645 I100 =6.59 42 ft2 0.033 acBasin 6:Area : 1,419 ft2 → min ܳଵ଴଴ ൌܥ ൈ ܫଵ଴଴ ൈܣ ܫଵ଴଴ ൌ 7.44ܲ଺ܦି଴.଺ସହ D SOWARDS AND BROWN ENGINEERING 2187 NEWCASTLE AVENUE, STE 103 CARDIFF BY THE SEA, CALIFORNIA 92007 JOB: 18-045 CHURCH RESIDENCE DATE: 8/18/2020 SHEET: 9 Q100 =0.04 cfs This Basin drains to Bioretention Basins where runoff is treated before being piped to an underground vault for flow mitigation, then sheet flows to the Agua Hedionda Lagoon I100 =6.59 in/hr Q100 = Peak Discharge (cfs) = 0.87 x 6.59 x 0.01 D = 5.00 I100 =7.44 x 2.5 x 5.00 ‐0.645 Tc = Time of Concentration (min) ◦ By inspection, Tc < 5 min Tc = 5.0 min I100 = Rainfall Intensity (in/hr) P6 = 2.50 Impervious Surfaces , C = 0.90 288 ft2 C = 0.87 : Weighted Runoff Coefficient Runoff Coefficient Soil Type 'B' , C = 0.25 15 ft2 Basin 7:Area : 303 ft2 →0.007 ac min ܳଵ଴଴ ൌܥ ൈ ܫଵ଴଴ ൈܣ ܫଵ଴଴ ൌ 7.44ܲ଺ܦି଴.଺ସହ D SOWARDS AND BROWN ENGINEERING 2187 NEWCASTLE AVENUE, STE 103 CARDIFF BY THE SEA, CALIFORNIA 92007 JOB: 18-045 CHURCH RESIDENCE DATE: 8/18/2020 SHEET: 10 This Basin drains to Bioretention Basins where runoff is treated before being piped to an underground vault for flow mitigation, then sheet flows to the Agua Hedionda Lagoon Q100 =0.05 cfs I100 =6.59 in/hr Q100 = Peak Discharge (cfs) = 0.90 x 6.59 x 0.01 D = 5.00 I100 =7.44 x 2.5 x 5.00 ‐0.645 Tc = Time of Concentration (min) ◦ By inspection, Tc < 5 min Tc = 5.0 min I100 = Rainfall Intensity (in/hr) P6 = 2.50 Impervious Surfaces , C = 0.90 380 ft2 C = 0.90 : Weighted Runoff Coefficient Runoff Coefficient Soil Type 'B' , C = 0.25 0 ft2 Basin 8:Area : 380 ft2 →0.009 ac min ܳଵ଴଴ ൌܥ ൈ ܫଵ଴଴ ൈܣ ܫଵ଴଴ ൌ 7.44ܲ଺ܦି଴.଺ସହ D SOWARDS AND BROWN ENGINEERING 2187 NEWCASTLE AVENUE, STE 103 CARDIFF BY THE SEA, CALIFORNIA 92007 JOB: 18-045 CHURCH RESIDENCE DATE: 8/18/2020 SHEET: 11 Q100 =0.05 cfs This Basin drains to Bioretention Basins where runoff is treated before being piped to an underground vault for flow mitigation, then sheet flows to the Agua Hedionda Lagoon I100 =6.59 in/hr Q100 = Peak Discharge (cfs) = 0.83 x 6.59 x 0.01 I100 = Rainfall Intensity (in/hr) P6 = 2.50 D = 5.00 I100 =7.44 x 2.5 x 5.00 ‐0.645 C = 0.83 : Weighted Runoff Coefficient Tc = Time of Concentration (min) ◦ By inspection, Tc < 5 min Tc = 5.0 min Impervious Surfaces , C = 0.90 372 ft2 Soil Type 'B' , C = 0.25 44 ft2 0.010 ac Runoff Coefficient Basin 9:Area : 416 ft2 → min ܳଵ଴଴ ൌܥ ൈ ܫଵ଴଴ ൈܣ ܫଵ଴଴ ൌ 7.44ܲ଺ܦି଴.଺ସହ D SOWARDS AND BROWN ENGINEERING 2187 NEWCASTLE AVENUE, STE 103 CARDIFF BY THE SEA, CALIFORNIA 92007 JOB: 18-045 CHURCH RESIDENCE DATE: 8/18/2020 SHEET: 12 Q100 =0.30 cfs I100 =6.59 in/hr Q100 = Peak Discharge (cfs) = 0.25 x 6.59 x 0.18 Tc = Time of Concentration (min) ◦ By inspection, Tc < 5 min Tc = 5.0 min D = 5.00 I100 =7.44 x 2.5 x 5.00 ‐0.645 I100 = Rainfall Intensity (in/hr) P6 = 2.50 Impervious Surfaces , C = 0.90 0 ft2 C = 0.25 : Weighted Runoff Coefficient Runoff Coefficient Soil Type 'B' , C = 0.25 8,088 ft2 Basin 10:Area : 8,021 ft2 →0.184 ac min This Basin sheet flows to the Agua Hedionda Lagoon ܳଵ଴଴ ൌܥ ൈ ܫଵ଴଴ ൈܣ ܫଵ଴଴ ൌ 7.44ܲ଺ܦି଴.଺ସହ D SOWARDS AND BROWN ENGINEERING 2187 NEWCASTLE AVENUE, STE 103 CARDIFF BY THE SEA, CALIFORNIA 92007 JOB: 15-010 LANG TENTATIVE PARCEL MAP DATE: 8/18/2020 SHEET: 13 : flow length (ft) I100 = Rainfall Intensity (in/hr) P6 = 2.50 D I100 =6.13 in/hr Tc =5.59cfs 14.75 min QJ2 = Peak Discharge (cfs) QJ2 =1.20 cfs T1 Q100 =0.30 cfs I100 =6.59 in/hr Tc =5.00 min cfsQ100 =0.18 + 0.56 = + 0.07 T3 0.74 TJ1 = 5.0 min I100 =6.59 Q100 =0.74 + 0.10 0.19 + 0.04 + T10 <TJ2Junction 3: JCT 1 & Basins 4, 5, 6, 7 & 9 + miles ∆E= JCT 2 & Basins 10 0.05 =T4 in/hr Per Sheet 15 = 1.20 cfs min5.0= TJ3 = L = 104 : flow length (ft)→0.020 (11.9 x 0.020 ³) 0.385 14.8 Junction Analysis Junction 1:Basins 2 & 3 T2 = 5.0 minT6= in/hr Junction 2: TJ2 = 5.0 min I100 =6.59 T5= min TJ3 = 5.00 + 0.59 = 5.59 TJ3 =0.010 hrs →0.59 = 5.59 I100 =7.44 x 2.5 x 5.59 ‐0.645 I100 =6.13 in/hr T2 Q100 =1.20 Basin 10: Junction 2: ܶ௃ଷ ൌ 11.9ܮଷ ∆ܧ ଴.ଷ଼ହ ܫଵ଴଴ ൌ 7.44ܲ଺ܦି଴.଺ସହ D D D D SOWARDS AND BROWN ENGINEERING 2187 NEWCASTLE AVENUE, STE 103 CARDIFF BY THE SEA, CALIFORNIA 92007 JOB: 15-010 LANG TENTATIVE PARCEL MAP DATE: 8/18/2020 SHEET: 14 QJ3 =1.48 cfs Tc =5.59 min I100 =6.13 in/hr 1.38 1.486.13QT2 =1.20+0.30 =6.59 5.00QT1 =0.30 + 1.20 =5.59 SOWARDS AND BROWN ENGINEERING 2187 NEWCASTLE AVENUE, STE 103 CARDIFF BY THE SEA, CALIFORNIA 92007 JOB: 18-045 CHURCH RESIDENCE DATE: 8/18/2020 SHEET: 15 1.48Junction 3 0.405 5.59 6.13 0.56 Junction 1 Junction 2 0.221 5.00 6.59 0.83 1.20 0.740.065 5.00 6.59 0.85 6.59 0.90 0.30 0.05 6.59 0.87 0.04 0.05 Basin Area (ac)Tc (min) 8 0.009 5.00 2 0.033 5.00 Basin Area (ac) 3 0.108 5.00 I100 (in/hr)C 0.184 5.00 6.59 0.25 6.59 0.83 I100 (in/hr)C 0.013 5.00 6.59 0.90 Tc (min) 0.010 0.19 5 0.018 5.00 6.59 0.87 6 0.033 5.00 6.59 0.88 0.13 6.59 0.82 10 7 0.007 5.00 4 9 5.00 6.59 0.79 0.07 0.18 0.56 0.10 Hydrology Summary Post‐Development Hydrology 1 Pre‐Development Hydrology A 0.451 5.85 0.034 5.00 6.59 0.59 Q100 (cfs) 5.95 0.25 0.67 Q100 (cfs) SOWARDS AND BROWN ENGINEERING 2187 NEWCASTLE AVENUE, STE 103 CARDIFF BY THE SEA, CALIFORNIA 92007 JOB: 18-045 CHURCH RESIDENCE DATE: 8/18/2020 SHEET: 16 Increased flow will be mitigated by an underground vault to meet hydromodificiation requirements. Tory R. Walker Engineering will compute and size the underground vault upon obtaining initial City review of proposed development. The current vault was sized based on vault sizing of previous projects. Q Attention (i.e. Detention Analysis) is not required due to no risk of flooding the adjacent lagoon. 3. 1.48 ‐ TC =5.00 min Q100 =1.48 cfs TC =5.59 min 2.Since the existing lot is undeveloped, there is an increase in impervious area and flow. Junction 3 represents the total sheet flow into the lagoon. The increase in flow is: 0.67 Basin 1 is a portion of the pre‐development flow that is re‐directed to the street as a result of street widening.  0.13 cfs is being re‐directed. 1. 0.810= cfs NOTES: Post‐Development Hydrology Hydraulics Summary Pre‐Development Hydrology Q100 =0.67 cfs TC =5.85 min Q100 =0.13 cfs Junction 1 & 2 are used for pipe sizing and are not included Junction 3: Basin 1: SOWARDS AND BROWN ENGINEERING 2187 NEWCASTLE AVENUE, STE 103 CARDIFF BY THE SEA, CALIFORNIA 92007 JOB: 18-045 CHURCH RESIDENCE DATE: 8/18/2020 SHEET: 17  ◦ Use 6" @ 1.0% min. ◦ Per sheet 13,, QMAX =0.66 cfs  Basin 6:Q100 =0.19 cfs ◦ Use 6" @ 1.0% min. ◦ Per sheet 13,, QMAX =0.66  Basin 5:Q100 =0.10 cfs min. ◦ Per sheet 13,, QMAX =0.66 cfs ◦ Per sheet 20,, QMAX =1.24 Basin 4: min. cfs ◦ Use 6" @ 1.0% cfs min. 0.66 ◦ Use 6" @ 1.0% Basin 7:Q100 =0.04 cfs Hydraulics Summary cfs 1.5% min.6" @  Q100 =0.74 cfsJunction 1: ◦ Use 1.20 cfs 0.81 cfs, QMAX = min.  ◦ Per sheet 19 ◦ Use 6" @ 3.5% Junction 2:Q100 = Q100 =0.07   Basin 9:Q100 =0.05 cfs , QMAX =0.66 cfs cfs, QMAX = ◦ Per sheet 13, ◦ Per sheet 13, ◦ Use 6" @ 1.0% Circular Channel Analysi s & Desi gn Solved with Manning's Equation Open Channel -Uniform f l ow Worksheet Name : Church Comment: 6" PVC@ 1% Solve For Full Fl ow Capacity Given Input Data: Diameter ......... . Slope ............ . Manning's n ...... . Discharge ........ . Compu ted Results : Full Flow Capacity .... . Full Flow Depth ....... . Velocity ......... . Flow Area ........ . Critical Depth ... . Critical Slope ... . Percent Full ..... . Full Capacity .... . QMAX @.94D ....... . Froude Number .... . 0.50 ft 0 .0100 ft/ft 0.011 0.66 cfs 0 .66 cfs 0.50 f t 3.38 fps 0 .20 sf 0.41 ft 0.0099 ft/ft 100.00 % 0 .66 cfs 0.71 cfs FULL Open Channel Flow Module, Ver sion 3.21 (c) 1990 Haestad Methods, Inc. * 37 Brookside Rd * Wate rbury, Ct 06708 Circular Cha nnel Anal ysis & Design Solved wi th Manning's Equation Open Channel -Uniform flow Worksheet Name: Church Comment : 6" PVC@ 1 .5% Sol ve For Ful l Flow Capacity Given Input Data: Diameter ......... . Slope ............ . Manning's n ...... . Discharge ... . Computed Results: Full Flow Capaci ty .... . Full Fl ow Depth ....... . Velocity ......... . Flow Area ........ . Crit ical Depth ... . Critical Slope ... . Percent Full ..... . Full Capaci ty .... . QMAX @.94D ....... . Froude Number .... . a.so ft 0 .0150 ft/ft 0 .011 0 .81 cfs 0 .81 cfs a.so ft 4 . 14 fps 0.20 sf 0.45 f t 0.0133 ft/ft 100.00 % 0 .81 cfs 0 .87 c f s FULL Open Channel Fl ow Module , Vers ion 3.21 (cl 1990 Haestad Methods, Inc. * 37 Brookside Rd* Waterbury, Ct 06708 Circular Channel Analysis & Design Solved with Manning's Equation Open Channel -Uniform flow Worksheet Name : Comment: 6" PVC @ 3 .5% Solve For Full Flow Capacit y Given Input Data: Diameter ......... . Slope ............ . Manning's n ...... . Discharge ....... . Comput ed Results : Full Flow Capaci ty .... . Full Flow Depth ....... . Velocity ......... . Flow Area ........ . Critical Depth ... . Critical Sl ope ... . Percent Full ..... . ?ull Capacity .... . QMAX @.94D ....... . Froude Number .... . a.so ft 0 .0350 ft/ft 0.011 1. 24 cfs 1. 24 cfs 0.50 ft 6 . 3 2 fps 0.20 sf 0 .49 ft 0.0311 ft/ft 100.00 % 1.24 cfs 1.33 cfs FULL Open Channel Flow Module, Version 3 .21 (c) 1990 Haestad Methods, Inc. * 37 Brookside Rd* Waterbury, Ct 06708 Circular Channel Analysis & Design Sol ved with Manning 's Equation Open Channel -Uniform flow Worksheet Name: Comment: 6" PVC @ 4 .5% Sol ve For Full Flow Capacity Given Input Data: Di ameter ......... . Sl ope ............ . Manning's n ...... . Discharge ........ . Computed Results : Full Flow Capacity ..... Full Flow Depth ........ Velocity .......... Flow Area ......... Critical Depth .... Critical Slope .... Percent Full ...... Full Capacity ..... QMAX @. 94D ........ Froude Number ..... 0.50 ft 0 .0450 ft/ft 0.011 1.41 cfs 1.41 cfs 0.50 f t 7 .16 fps 0 .20 sf 0. 4 9 ft 0.0408 ft/ft 100.00 % 1. 41 cfs 1.51 cfs FULL Open Channel Flow Module, Version 3.21 (c) 1990 Haestad Methods, Inc . * 37 Brookside Rd * Waterbury, Ct 06708 Hydrologic Soil Group—San Diego County Area, California Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 1/23/2014 Page 1 of 4 36 6 7 2 0 0 36 6 7 3 0 0 36 6 7 4 0 0 36 6 7 5 0 0 36 6 7 6 0 0 36 6 7 7 0 0 36 6 7 2 0 0 36 6 7 3 0 0 36 6 7 4 0 0 36 6 7 5 0 0 36 6 7 6 0 0 36 6 7 7 0 0 469200 469300 469400 469500 469600 469700 469800 469900 470000 470100 469200 469300 469400 469500 469600 469700 469800 469900 470000 470100 33° 8' 54'' N 11 7 ° 1 9 ' 5 2 ' ' W 33° 8' 54'' N 11 7 ° 1 9 ' 1 2 ' ' W 33° 8' 32'' N 11 7 ° 1 9 ' 5 2 ' ' W 33° 8' 32'' N 11 7 ° 1 9 ' 1 2 ' ' W N Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 11N WGS84 0 200 400 800 1200Feet 0 50 100 200 300Meters Map Scale: 1:4,740 if printed on A landscape (11" x 8.5") sheet. USDA "' MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Rating Polygons A A/D B B/D C C/D D Not rated or not available Soil Rating Lines A A/D B B/D C C/D D Not rated or not available Soil Rating Points A A/D B B/D C C/D D Not rated or not available Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding 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: http://websoilsurvey.nrcs.usda.gov Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction 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 the version date(s) listed below. Soil Survey Area: San Diego County Area, California Survey Area Data: Version 7, Nov 15, 2013 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: May 3, 2010—Jun 19, 2010 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 result, some minor shifting of map unit boundaries may be evident. Hydrologic Soil Group—San Diego County Area, California Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 1/23/2014 Page 2 of 4USDA "' □ D D D D D D D D ,....,,. ,....,,. ,....,,. ■ ■ □ □ ,,..._, H-t ~ _,,., ~ --• Hydrologic Soil Group Hydrologic Soil Group— Summary by Map Unit — San Diego County Area, California (CA638) Map unit symbol Map unit name Rating Acres in AOI Percent of AOI CbC Carlsbad gravelly loamy sand, 5 to 9 percent slopes B 5.7 5.4% CbD Carlsbad gravelly loamy sand, 9 to 15 percent slopes B 7.4 7.0% GaF Gaviota fine sandy loam, 30 to 50 percent slopes D 11.6 11.0% LfC Las Flores-Urban land complex, 2 to 9 percent slopes D 18.6 17.6% LG-W Lagoon water 30.4 28.9% LvF3 Loamy alluvial land- Huerhuero complex, 9 to 50 percent slopes, severely eroded D 4.3 4.1% MlE Marina loamy coarse sand, 9 to 30 percent slopes B 27.3 26.0% Totals for Area of Interest 105.2 100.0% Hydrologic Soil Group—San Diego County Area, California Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 1/23/2014 Page 3 of 4 USDA ,., 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 (A/D, B/D, 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 potential, soils that have a high water table, soils that have a claypan or clay layer at or near 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 (A/D, B/D, 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 D are assigned to dual classes. Rating Options Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher Hydrologic Soil Group—San Diego County Area, California Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 1/23/2014 Page 4 of 4~ San Diego County Hydrology Manual Date: June 2003 Table 3-1 Section: Page: RUNOFF COEFFICIENTS FOR URBAN AREAS Land Use Runoff Coefficient "C" Soil Type NRCS Elements Coun Elements %IMPER. A B Undisturbed Natural Terrain (Natural) Permanent Open Space 0* 0.20 0.25 Low Density Residential (LDR) Residential, 1.0 DU/A or less 10 0.27 0.32 Low Density Residential (LDR) Residential, 2.0 DU/A or less 20 0.34 0.38 Low Density Residential (LDR) Residential, 2.9 DU/A or less 25 0.38 0.41 Medium Density Residential (MDR) Residential, 4.3 DU/A or less 30 0.41 0.45 Medium Density Residential (MDR) Residential, 7.3 DU/A or less 40 0.48 0.51 Medium Density Residential (MDR) Residential, 10.9 DU/A or less 45 0.52 0.54 Medium Density Residential (MDR) Residential, 14.5 DU/A or less 50 0.55 0.58 High Density Residential (HDR) Residential, 24.0 DU/A or less 65 0.66 0.67 High Density Residential (HDR) Residential, 43.0 DU/A or less 80 0.76 0.77 Commercial/lndustrial (N. Com) Neighborhood Commercial 80 0.76 0.77 Commercial/lndustrial (G. Com) General Commercial 85 0.80 0.80 Commercial/lndustrial (O.P. Com) Office Professional/Commercial 90 0.83 0.84 Commercial/lndustrial (Limited I.) Limited Industrial 90 0.83 0.84 Commercial/lndustrial General I. General Industrial 95 0.87 0.87 C 0.30 0.36 0.42 0.45 0.48 0.54 0.57 0.60 0.69 0.78 0.78 0.81 0.84 0.84 0.87 3 6 of26 D 0.35 0.41 0.46 0.49 0.52 0.57 0.60 0.63 0.71 0.79 0.79 0.82 0.85 0.85 0.87 *The values associated with 0% impervious may be used for direct calculation of the runoff coefficient as described in Section 3 .1.2 (representing the pervious runoff coefficient, Cp, for the soil type), or for areas that will remain undisturbed in perpetuity. Justification must be given that the area will remain natural forever (e.g., the area is located in Cleveland National Forest). DU/A= dwelling units per acre NRCS = National Resources Conservation Service 3-6 : : t :~+ + + + + + + + 33°310'1'-,;c--~-'-';;------ff==1~"'6'1"--------++--f-+-L-++--_J_L___--J-----l_j_-------'-+-l__----L__l _ _J_.'.__-+-__j__-L_ ___ -------l--rr--r-r------3n•7 + "' t:tHH 0 + "' -~ p + i:; ~ + + + r + + + + + . . . i l•'· / ;. "·~---· ..-1· -L./ r •• ,• . .. .... ........ .... :· ~·· I--,•~ .;>·:-.~f~::t'· I f c i- t Hi + ft+ tt+t++ + t t: ·33°15w'-:-r---'-!--t-----t-'-----~:-;---r;-;;;A~....-".''lf"<-""'-'_...+-i...,,..="'r--,,+-rlf------l-L~'.+,,--,-:,;~-'.:~.L.....c.:,,.c-'.J...L:"--'~FH~+-tt--+i--J >'•n.-~~-'\.. ... : I r"'":-/ 1 ('l .,. ~ 33°Q011 ~-~~1 ~'c,;a;,--=-::::-:;:::::::::JJlJ i 1;:--->t--'------'i'-'f-tt+f.H.~-'-'----'-nf'~--t-~tb::±fr:.':71t-'ft---'---'{------i-t--H"-1 -+---33°00· f--t;•··· ·: ... _.... . -. . :.•.-, ··-.. r.. ·::--.. 1\'t ··:t)· ;-'. . . .. . .. ~\ \-\.\' .\ + + + + + + + + + + +: ~ t+ + t dr 32°30' ~ ~1 <D + + + + + + f + t+ t I County of San Diego Hydrology Manual Rainfall Isopluvials 100 Year Rainfall Event -6 Hours lsopluvial (inches) DPW ~GIS ~GIS Oepamr..,,,r,1p,,t;;c,1~ '3-.rJp>11<mtr,,.iWOt1Sw,,icu .. 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PARTICLlAR PURPOSE C.Op>frigh\SeinGIS.AIIRight:eR-«! s Tllis products may contain lnloonallon from Iha SNIIOAG Regional E =~mor~~bereproducedwtthoullhe Tllisproductmaycootalnl!lfom>atlonwhk:hhasbeeoraproduced"'"'1 pennlsliongrantedb)'ThornasBrolhersMape 3 O 3 Miles ~- 100 2.5 4.5 56 2.5 5.0 6.59 10.0 9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 ~:5~ 0 .c <ii Q) .c g1.0 ~09 ~08 Q) Eo7 0.6 0.5 0.4 0.3 0.2 ' ' ' ' ... ' ' ' ' ' "' .... ' .... . ' .... , ... ~ ' .... ' . ' .... ~ ' .... ' . ' ... ' ' .... , ' ... r-.. !,..., ' .... , .... I'. ,, I"'' ... 'r-.. ·, ,, .. r-' ~ .. .... ' .... ,. ' .. I"' I'-"' ' • .. "" ~ .. ... I'. '"" ... ' i--., "", ~ .. .... .. , ... ,, ~ ~ ·, ""' 'r-.. ,,. ~ .. ... , .... ' I"' ~ .... ,. 'r-·, ',, ,. ~ , .. ''r-,, .... , 'i--,, ""' ~ 0.1 , , 5 6 7 8 9 10 15 20 ~ ~ ~ ~ ~ ~ .. ~ ~ ~ .. ~ .. 30 Minutes ~ .. ~ .. ~ '"" .... ~ ~r-~ .. ~ ~ .. .. ~ .. ~ .. .. .. ~ '"" ~ .. ~ ~ ""~ 40 50 Duration I = I = p6 = D = EQUATION 7.44 P6 D-0.645 Intensity (in/hr) 6-Hour Precipitation (in) Duration (min) 'r--. .... ' .... ,, I'. ,, ' I', r--. ' ,, ' 'i--'r-- ' ... , , ... 'i-- ' I', 'r--. ,, 2 ', ', .. ... .... ' ', ~ .. ""· .... ', ', ' ~ "" .. ... , . .... , .. .... , .. , ' I"' ', '"" I" I" 3 Hours .. ~ ~ .. .. ~ ~ ~ ~ 4 5 6 '{' I 0 ~ 7J ro 0 6.0 R 5.5 !!l. 5.0 g 4.5 '§' 0 4.0 ~ 3.5 ~ 3.0 2.5 2.0 1.5 1.0 Intensity-Duration Design Chart -Template Directions for Application: (1) From precipitation maps determine 6 hr and 24 hr amounts for the selected frequency. These maps are included in the County Hydrology Manual (10, 50, and 100 yr maps included in the Design and Procedure Manual). (2) Adjust 6 hr precipitation (if necessary) so that it is within the range of 45% to 65% of the 24 hr precipitation (not applicaple to Desert). (3) Plot 6 hr precipitation on the right side of the chart. ( 4) Draw a line through the point parallel to the plotted lines. (5) This line is the intensity-duration curve for the location being analyzed. Application Form: (a) Selected frequency ___ year p (b) Ps = __ in., P24 = --'P 6 = %(2) 24 (c) Adjusted p 6<2> = ___ in. (d) Ix= __ min. (e) I= __ in./hr. Note: This chart replaces the Intensity-Duration-Frequency curves used since 1965. I P6 1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 6 Duration I I I I I I I I I I I I 5 2.63 3.95 5.27 6.59 7.90 9.22 10.54 11.86 13.17 14.49 15.81 7 2.12 3.18 4.24 5.30 6.36 7.42 8.48 9.54 10.60 11.66 12.72 10 1.68 2.53 3.37 4.21 5.05 5.90 6.74 7.58 8.42 9.27 10.11 15 1.30 1.95 2.59 3.24 3.89 4.54 5.19 5.84 6.49 7.13 7.78 20 1.08 1.62 2.15 2.69 3.23 3.77 4.31 4.85 5.39 5.93 6.46 -25 0.93 1.40 1.87 2.33 2.80 3.27 3.73 4.20 4.67 5.13 5.60 30 0.83 1.24 1.66 2.07 2.49 2.90 3.32 3.73 4.15 4.56 4.98 ~ 0.69 1.03 1.38 1.72 2.07 2.41 2.76_ 3.10_ 3.45 3.79 4.13 50 0.60 0.90 1.19 1.49 1.79 2.09 2.39 2.69 2.98 3.28 3.58 --60 0.53 0.80 1.06 1.33 1.59 1.86 ,_?.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 2.04 2.25 ~2.45 120 0.34 0.51 0.68 0.85 1.02 1.19 1.36 1.53 1.70 1.87 2.04 150 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 0.78 0.91 1.04 1.18 1.31 1.44 1.57 240 0.22 0.33 0.43 0.54 0.65 0.76 0.87 0.98 1.08 1.19 1.30 300 0.19 0.28 0.38 0.47 0.56 0.66 0.75 0.85 0.94 1.03 1.13 360 0.17 0.25 0.33 0.42 0.50 0.58 0.67 0.75 0.84 0.92 1.00 FIGURE ~ f-w w LL z w (.) z <( f-Cl) 0 w Cl) 0::: => 0 (.) 0::: w ~ 3;: 2.50% slope---111 2.0--1-----1# 1001----=-1...:c•5,,,_---1-_-_-_-_-_--.,~ ... ~ .. "'!!.-..,.._---- 0 EXAMPLE: Given: Watercourse Distance (D) = 70 Feet Slope (s) = 1.3% Runoff Coefficient (C) = 0.41 Overland Flow Time (T) = 9.5 Minutes SOURCE: Airport Drainage, Federal Aviation Administration, 1965 T = 1.8 (1.1-C) VD 3'fs Cf) w f-=> z 20 ~ z w ~ i= 3;: 0 ....J LL 0 z <( ....J 0::: w > 0 FIGURE Rational Formula -Overland Time of Flow Nomograph 3-3 .6E Feet 5000 4000 Tc Tc L .6E = = = = EQUATION {1:.;.9~3)°.385 Time of concentration (hours) Watercourse Distance (mites) Change in elevation along effective slope line (See Figure 3-S)(feet) .6E 3000 2000 1000 0 0 0 } ' 500' 400 300 200 100 30 20 10 5 ' ' '~ 'ci)'Q. ~'$ ' ' ' ' ' ' ' ' L Miles Feet '1 3000 0.5 ' 2000 1800 1600 1400 1200 1000 900 800 700 600 500 400 300 200 L ' SOURCE: California Division of Highways (1941) and Kirpich (1940) Nomograph for Determination of ' ' Tc Hours Minutes 4 3 2 ' ' ' Tc 50 40 30 20 18 16 14 12 10 9 8 7 6 5 4 3 Time of Concentration (Tc) or Travel Time (Tt) for Natural \Vatersheds FIGURE ~ N I -l!2 as i ~ "' -"' i;5 !fl - I • I • I • A I I I • I • I I I • I 1 ~ i • kJ . I I t2 I • It=; i I • • I, I Ii • I • • I I I I • • I I • • I I • I • I I • • I \ • ~ ~, • t ., I • I ~-2s j () I I ~ I I i • I • • I I I • I I • j ~; I I • ~ I • I .. I • I • I ~ I I I I I I I L I ,L I I L I IL I ~ ; L I f8 IL I ,l l5 I ,1 I L I L I If I I I I I I : l I l I L I L ~ ~I l !\ I l I ~ I f I \ I l I I I I I I I I I I I I I I I ----...__ I I I I I ~ ~ ~ ~ ' I PRE-DEVELOPMENT DRAINAGE MAP ... ,,, "' ,,, "' "'\ ct. SIN ~ An -19,6 0 SF -0.45 \c C2 = 0.25 I I I I I I I "' I "' I I I I I I I I I I I I l100 = 5. 95 IN IHR 0100 = 0. 6 CFS I I I I I I I I I I I I I I I I I I I I I I I I I I I I • ii ii ii ii II ... I ' I I I I I I I I I • I I _, f' ..,Sc! I II \ ii \ I /2 \ .., I II ii ... 1 I I I \ I • I • I • I • I UM/TS OF SAND I SCALE: 1"=10' I ,f 'f I ' I ' ' ' ' I ' ~ROP£FENCE ' I/ 'I --------------1 I I I I I I I I I I I I I I I I I I I I I I I I I I lll✓r----J+-._ MEAN HIGH 11DE UNE AS OF ,JJNE 25, 2018 ELEVA 110N = 2.25 FLOOD PLAIN BOUNDARY PER FEMA MAP 0607JC0764G I I I I \ \ \ -I X .-.-.-.-I -------------- I I I I I PRE-DEVELOPMENT DRAINAGE JOB NO. 18-045 B/18/20 SOWARDS & BROWN ENGINEERING CONSUL TING ENGINEERS 2187 NEWCASTLE AVENUE SUITE 1 03 CARDIFF BY THE SEA, CA., 92007 TEL. 760/436-8500 FAX 760/436-BBOa 0 .._ ______________________________________________________________________________________________________________ _. D:\DRAWING FILES\TITLE SHEETS\GRADING TITLE SHEET.DWG REVISE0:02/15/17 N ~ "' ~ ~I e2 -('; -iS §§ iS "' 6 J, -,a! 25 a.. ~ e: c;l ij I -i:'2 as ~ -~ V) -V) es sg - BAS/ I " I " I 1 ' ' ' ' " ~ I I I I I I I I I I I I I I I I I I I I BASIN 3 A3 = 4,714 SF= 0.108 AC C3=0.79 l100 = 6.59 INIHR 0 100 = 0. 56 CFS ' ,·~~ \ ~ ''? ' '£ ~: \ ~.' Ifs ----"""- BASIN 2 A2 = 1,420 SF = 0.033 AC C2 = 0.82 l100 = 6.59 INIHR 0 100 = 0.18 CFS BASIN 4 POST-DEVELOPMENT DRAINAGE MAP ....c:::::::::::))= =:..._ _ ___..< JUNCTION 1 0 100 = 0. 74 CFS A4 = 551 SF = 0.013 AC C4 = 0.90 l100 = 6.59 INIHR 0100 = 0.07 CFS DE MIN/MUS A = 69 SF = 0.002 ~C BASIN 6 A5 = 1,419 SF = 0.033 AC C6 = 0.88 l100 = 6.59 INIHR 0 100 = 0.19 CFS I BASIN 5 As = 789 SF = 0.018 AC Cs = 0.87 l100 = 6.59 INIHR 0 100 = 0.10 CFS I I I I I BASIN 7 A7 _ 303 SF = 0.007 AC BASIN g C1 -0.87 ~~~~---- 1100 = 6.59 INIHR Ag = 416 SF = 0.010 AC 0100 = 0.04 CFS Cg = 0-83 IN I l100 = 6.59 I HR 0100 = 0. 05 CFS JUNCTION 2 • I \ .,.g \ C // \ ~ BAStN 10 A10 =\ 8,021 SF = 1.184 BASIN al A8 = 380 .F = 0.009 AC Ca= 0.90 / l100 = 6.59 INIHR 0100 = 0. Q5 CFS I ... \ // \ / J \ C10 = \0.25 / l100 = 6.59 I ">(HR 0 100 = 0. 30 OF/ A n // ... ? /\ ? ... 1 18.35' FROM 10P[RTY MONUi [NT TO 10? UFFER LINE i i ? Ii \I L I \ I \ \ I SCALE: 1"=10' I I I --------------1 I __, I I I I I I I I I I I I I I I I I I I I I I MEAN HIGH TIDE UNE AS OF ,JJNE 25, 2018 ELEVATION = 2.25 I I I -------------- I I I --;' I I I POST-DEVELOPMENT DRAINAGE JOB NO. 18-045 B/18/20 SOWARDS & BROWN ENGINEERING CONSUL TING ENGINEERS 2187 NEWCASTLE AVENUE SUITE 1 03 CARDIFF BY THE SEA, CA., 92007 TEL. 760/436-8500 FAX 760/436-BBOa G._ _______________________________________________________________________________________________________________________ _. D: \DRAWING FILES\111LE SHEETS\GRACING TITLE SHEET.DWG RE\IISED:02/15/17