HomeMy WebLinkAboutPD 2022-0012; POFF ADU; HYDROLOGY STUDY FOR POFF ADU; 2023-03-01HYDROLOGY STUDY
POFF ADU
PD 2022-0012, GR 2022-0018, DWG. 537-6A
CITY OF CARLSBAD
Prepared for:
Alex Poff
4374 Tuolumne Place
Carlsbad, CA 92010
Prepared by:
bhA, INC
land planning, civil engineering, surveying
5115 Avenida Encinas, Suite L
Carlsbad, CA 92008-4387
(760) 931-8700
March 01, 2023
w.o. 1146-1517-600
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TABLE OF CONTENTS
Chapter 1 – Exhibits .................................................................................................................................. 3
1.1 Existing Hydrology Map ............................................................................................ 4
1.2 Developed Hydrology Map ....................................................................................... 5
Chapter 2 – Rational Hydrology Calculations (100-Year Storm Event) .............................................. 6
2.1 Existing Hydrologic Analysis ............................................................................. 7
2.2 Developed Hydrologic Analysis ......................................................................... 9
Chapter 3 – References ............................................................................................................................ 15
3.1 References ......................................................................................................... 16
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Chapter 1
Exhibits
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Chapter 1.1
Existing Hydrology Map
EXIST. HOUSE
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Chapter 1.2
Developed Hydrology Map
EXIST. HOUSE
FF=354.89
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7
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Chapter 2
100-Year Storm Rational Hydrology Calculations
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2.1 Existing Condition Hydrologic Analysis
100-YEAR STORM
************************************************************************************** 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 CONDITION 100-YEAR STORM HYDROLOGY * * POFF ADU * * 1146-1517-600 * ************************************************************************** FILE NAME: K:\HYDRO\1517\1517E100.DAT TIME/DATE OF STUDY: 13:43 04/27/2022 ---------------------------------------------------------------------------- USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION: ---------------------------------------------------------------------------- 2003 SAN DIEGO MANUAL CRITERIA USER SPECIFIED STORM EVENT(YEAR) = 100.00 6-HOUR DURATION PRECIPITATION (INCHES) = 2.810 SPECIFIED MINIMUM PIPE SIZE(INCH) = 3.00 SPECIFIED PERCENT OF GRADIENTS(DECIMAL) TO USE FOR FRICTION SLOPE = 0.95 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 = .2500 S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET) = 100.00 UPSTREAM ELEVATION(FEET) = 352.00 DOWNSTREAM ELEVATION(FEET) = 325.40
ELEVATION DIFFERENCE(FEET) = 26.60
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SUBAREA OVERLAND TIME OF FLOW(MIN.) = 7.102 WARNING: THE MAXIMUM OVERLAND FLOW SLOPE, 10.%, IS USED IN Tc CALCULATION! 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 5.904 SUBAREA RUNOFF(CFS) = 0.27 TOTAL AREA(ACRES) = 0.18 TOTAL RUNOFF(CFS) = 0.27 +--------------------------------------------------------------------------+ | POC-1 | | | | | +--------------------------------------------------------------------------+ ============================================================================ END OF STUDY SUMMARY: TOTAL AREA(ACRES) = 0.2 TC(MIN.) = 7.10 PEAK FLOW RATE(CFS) = 0.27 ============================================================================ ============================================================================ END OF RATIONAL METHOD ANALYSIS
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2.2 Developed Condition Hydrologic Analysis
100-YEAR STORM
************************************************************************************** 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 ************************** * DEVELOPED CONDITION 100-YEAR STORM HYDROLOGY * * POFF ADU * * 1146-1517-600 * ************************************************************************** FILE NAME: K:\HYDRO\1517\1517P100.DAT TIME/DATE OF STUDY: 17:34 02/28/2023 ---------------------------------------------------------------------------- USER SPECIFIED HYDROLOGY AND HYDRAULIC MODEL INFORMATION: ---------------------------------------------------------------------------- 2003 SAN DIEGO MANUAL CRITERIA USER SPECIFIED STORM EVENT(YEAR) = 100.00 6-HOUR DURATION PRECIPITATION (INCHES) = 2.810 SPECIFIED MINIMUM PIPE SIZE(INCH) = 3.00 SPECIFIED PERCENT OF GRADIENTS(DECIMAL) TO USE FOR FRICTION SLOPE = 0.95
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 = .2500 S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET) = 58.00 UPSTREAM ELEVATION(FEET) = 352.00
DOWNSTREAM ELEVATION(FEET) = 332.75
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ELEVATION DIFFERENCE(FEET) = 19.25 SUBAREA OVERLAND TIME OF FLOW(MIN.) = 5.409 WARNING: THE MAXIMUM OVERLAND FLOW SLOPE, 10.%, IS USED IN Tc CALCULATION! 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 7.038 SUBAREA RUNOFF(CFS) = 0.05 TOTAL AREA(ACRES) = 0.03 TOTAL RUNOFF(CFS) = 0.05 **************************************************************************** FLOW PROCESS FROM NODE 20.00 TO NODE 30.00 IS CODE = 7 ---------------------------------------------------------------------------- >>>>>USER SPECIFIED HYDROLOGY INFORMATION AT NODE<<<<< ============================================================================ USER-SPECIFIED VALUES ARE AS FOLLOWS: TC(MIN) = 5.41 RAIN INTENSITY(INCH/HOUR) = 7.04 TOTAL AREA(ACRES) = 0.03 TOTAL RUNOFF(CFS) = 0.05 **************************************************************************** FLOW PROCESS FROM NODE 30.00 TO NODE 30.00 IS CODE = 81 ---------------------------------------------------------------------------- >>>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW<<<<< ============================================================================ 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 7.038 *USER SPECIFIED(SUBAREA): USER-SPECIFIED RUNOFF COEFFICIENT = .6700 S.C.S. CURVE NUMBER (AMC II) = 0 AREA-AVERAGE RUNOFF COEFFICIENT = 0.3368 SUBAREA AREA(ACRES) = 0.01 SUBAREA RUNOFF(CFS) = 0.04 TOTAL AREA(ACRES) = 0.0 TOTAL RUNOFF(CFS) = 0.09 TC(MIN.) = 5.41 **************************************************************************** FLOW PROCESS FROM NODE 30.00 TO NODE 30.00 IS CODE = 7 ---------------------------------------------------------------------------- >>>>>USER SPECIFIED HYDROLOGY INFORMATION AT NODE<<<<< ============================================================================ USER-SPECIFIED VALUES ARE AS FOLLOWS: TC(MIN) = 5.41 RAIN INTENSITY(INCH/HOUR) = 7.04 TOTAL AREA(ACRES) = 0.04 TOTAL RUNOFF(CFS) = 0.10 **************************************************************************** FLOW PROCESS FROM NODE 30.00 TO NODE 60.00 IS CODE = 41 ---------------------------------------------------------------------------- >>>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA<<<<< >>>>>USING USER-SPECIFIED PIPESIZE (EXISTING ELEMENT)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 327.30 DOWNSTREAM(FEET) = 326.87 FLOW LENGTH(FEET) = 43.26 MANNING'S N = 0.013 DEPTH OF FLOW IN 4.0 INCH PIPE IS 2.1 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 2.14 GIVEN PIPE DIAMETER(INCH) = 4.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 0.10 PIPE TRAVEL TIME(MIN.) = 0.34 Tc(MIN.) = 5.75 LONGEST FLOWPATH FROM NODE 10.00 TO NODE 60.00 = 101.26 FEET. **************************************************************************** FLOW PROCESS FROM NODE 60.00 TO NODE 60.00 IS CODE = 1 ---------------------------------------------------------------------------- >>>>>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE<<<<< ============================================================================ TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 1 ARE: TIME OF CONCENTRATION(MIN.) = 5.75 RAINFALL INTENSITY(INCH/HR) = 6.77
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TOTAL STREAM AREA(ACRES) = 0.04 PEAK FLOW RATE(CFS) AT CONFLUENCE = 0.10 **************************************************************************** FLOW PROCESS FROM NODE 40.00 TO NODE 50.00 IS CODE = 21 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< ============================================================================ *USER SPECIFIED(SUBAREA): USER-SPECIFIED RUNOFF COEFFICIENT = .2500 S.C.S. CURVE NUMBER (AMC II) = 0 INITIAL SUBAREA FLOW-LENGTH(FEET) = 75.00 UPSTREAM ELEVATION(FEET) = 352.00 DOWNSTREAM ELEVATION(FEET) = 332.77 ELEVATION DIFFERENCE(FEET) = 19.23 SUBAREA OVERLAND TIME OF FLOW(MIN.) = 6.151 WARNING: THE MAXIMUM OVERLAND FLOW SLOPE, 10.%, IS USED IN Tc CALCULATION! 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.478 SUBAREA RUNOFF(CFS) = 0.09 TOTAL AREA(ACRES) = 0.05 TOTAL RUNOFF(CFS) = 0.09 **************************************************************************** FLOW PROCESS FROM NODE 50.00 TO NODE 60.00 IS CODE = 7 ---------------------------------------------------------------------------- >>>>>USER SPECIFIED HYDROLOGY INFORMATION AT NODE<<<<< ============================================================================ USER-SPECIFIED VALUES ARE AS FOLLOWS: TC(MIN) = 6.15 RAIN INTENSITY(INCH/HOUR) = 6.48 TOTAL AREA(ACRES) = 0.05 TOTAL RUNOFF(CFS) = 0.09 **************************************************************************** FLOW PROCESS FROM NODE 60.00 TO NODE 60.00 IS CODE = 1 ---------------------------------------------------------------------------- >>>>>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE<<<<< >>>>>AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES<<<<< ============================================================================ TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 2 ARE: TIME OF CONCENTRATION(MIN.) = 6.15 RAINFALL INTENSITY(INCH/HR) = 6.48 TOTAL STREAM AREA(ACRES) = 0.05 PEAK FLOW RATE(CFS) AT CONFLUENCE = 0.09 ** CONFLUENCE DATA ** STREAM RUNOFF Tc INTENSITY AREA NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE) 1 0.10 5.75 6.767 0.04 2 0.09 6.15 6.478 0.05 RAINFALL INTENSITY AND TIME OF CONCENTRATION RATIO CONFLUENCE FORMULA USED FOR 2 STREAMS. ** PEAK FLOW RATE TABLE ** STREAM RUNOFF Tc INTENSITY NUMBER (CFS) (MIN.) (INCH/HOUR) 1 0.18 5.75 6.767 2 0.19 6.15 6.478 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE(CFS) = 0.19 Tc(MIN.) = 6.15 TOTAL AREA(ACRES) = 0.1 LONGEST FLOWPATH FROM NODE 10.00 TO NODE 60.00 = 101.26 FEET.
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**************************************************************************** FLOW PROCESS FROM NODE 60.00 TO NODE 70.00 IS CODE = 41 ---------------------------------------------------------------------------- >>>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA<<<<< >>>>>USING USER-SPECIFIED PIPESIZE (EXISTING ELEMENT)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 326.87 DOWNSTREAM(FEET) = 326.65 FLOW LENGTH(FEET) = 16.38 MANNING'S N = 0.013 DEPTH OF FLOW IN 4.0 INCH PIPE IS 2.9 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 2.72 GIVEN PIPE DIAMETER(INCH) = 4.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 0.19 PIPE TRAVEL TIME(MIN.) = 0.10 Tc(MIN.) = 6.25 LONGEST FLOWPATH FROM NODE 10.00 TO NODE 70.00 = 117.64 FEET. **************************************************************************** FLOW PROCESS FROM NODE 70.00 TO NODE 70.00 IS CODE = 81 ---------------------------------------------------------------------------- >>>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW<<<<< ============================================================================ 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.410 *USER SPECIFIED(SUBAREA): USER-SPECIFIED RUNOFF COEFFICIENT = .3700 S.C.S. CURVE NUMBER (AMC II) = 0 AREA-AVERAGE RUNOFF COEFFICIENT = 0.3332 SUBAREA AREA(ACRES) = 0.02 SUBAREA RUNOFF(CFS) = 0.06 TOTAL AREA(ACRES) = 0.1 TOTAL RUNOFF(CFS) = 0.24 TC(MIN.) = 6.25 **************************************************************************** FLOW PROCESS FROM NODE 70.00 TO NODE 100.00 IS CODE = 41 ---------------------------------------------------------------------------- >>>>>COMPUTE PIPE-FLOW TRAVEL TIME THRU SUBAREA<<<<< >>>>>USING USER-SPECIFIED PIPESIZE (EXISTING ELEMENT)<<<<< ============================================================================ ELEVATION DATA: UPSTREAM(FEET) = 326.65 DOWNSTREAM(FEET) = 321.00 FLOW LENGTH(FEET) = 24.01 MANNING'S N = 0.013 DEPTH OF FLOW IN 4.0 INCH PIPE IS 1.4 INCHES PIPE-FLOW VELOCITY(FEET/SEC.) = 8.59 GIVEN PIPE DIAMETER(INCH) = 4.00 NUMBER OF PIPES = 1 PIPE-FLOW(CFS) = 0.24 PIPE TRAVEL TIME(MIN.) = 0.05 Tc(MIN.) = 6.30 LONGEST FLOWPATH FROM NODE 10.00 TO NODE 100.00 = 141.65 FEET. **************************************************************************** FLOW PROCESS FROM NODE 80.00 TO NODE 100.00 IS CODE = 81 ---------------------------------------------------------------------------- >>>>>ADDITION OF SUBAREA TO MAINLINE PEAK FLOW<<<<< ============================================================================ 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 6.380 *USER SPECIFIED(SUBAREA): USER-SPECIFIED RUNOFF COEFFICIENT = .2500 S.C.S. CURVE NUMBER (AMC II) = 0 AREA-AVERAGE RUNOFF COEFFICIENT = 0.3263 SUBAREA AREA(ACRES) = 0.01 SUBAREA RUNOFF(CFS) = 0.02 TOTAL AREA(ACRES) = 0.1 TOTAL RUNOFF(CFS) = 0.25 TC(MIN.) = 6.30 **************************************************************************** FLOW PROCESS FROM NODE 100.00 TO NODE 110.00 IS CODE = 1 ---------------------------------------------------------------------------- >>>>>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE<<<<< ============================================================================
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TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 1 ARE: TIME OF CONCENTRATION(MIN.) = 6.30 RAINFALL INTENSITY(INCH/HR) = 6.38 TOTAL STREAM AREA(ACRES) = 0.12 PEAK FLOW RATE(CFS) AT CONFLUENCE = 0.25 **************************************************************************** FLOW PROCESS FROM NODE 90.00 TO NODE 110.00 IS CODE = 22 ---------------------------------------------------------------------------- >>>>>RATIONAL METHOD INITIAL SUBAREA ANALYSIS<<<<< ============================================================================ *USER SPECIFIED(SUBAREA): USER-SPECIFIED RUNOFF COEFFICIENT = .4400 S.C.S. CURVE NUMBER (AMC II) = 0 USER SPECIFIED Tc(MIN.) = 5.000 100 YEAR RAINFALL INTENSITY(INCH/HOUR) = 7.404 SUBAREA RUNOFF(CFS) = 0.20 TOTAL AREA(ACRES) = 0.06 TOTAL RUNOFF(CFS) = 0.20 **************************************************************************** FLOW PROCESS FROM NODE 110.00 TO NODE 110.00 IS CODE = 1 ---------------------------------------------------------------------------- >>>>>DESIGNATE INDEPENDENT STREAM FOR CONFLUENCE<<<<< >>>>>AND COMPUTE VARIOUS CONFLUENCED STREAM VALUES<<<<< ============================================================================ TOTAL NUMBER OF STREAMS = 2 CONFLUENCE VALUES USED FOR INDEPENDENT STREAM 2 ARE: TIME OF CONCENTRATION(MIN.) = 5.00 RAINFALL INTENSITY(INCH/HR) = 7.40 TOTAL STREAM AREA(ACRES) = 0.06 PEAK FLOW RATE(CFS) AT CONFLUENCE = 0.20 ** CONFLUENCE DATA ** STREAM RUNOFF Tc INTENSITY AREA NUMBER (CFS) (MIN.) (INCH/HOUR) (ACRE) 1 0.25 6.30 6.380 0.12 2 0.20 5.00 7.404 0.06 RAINFALL INTENSITY AND TIME OF CONCENTRATION RATIO CONFLUENCE FORMULA USED FOR 2 STREAMS. ** PEAK FLOW RATE TABLE ** STREAM RUNOFF Tc INTENSITY NUMBER (CFS) (MIN.) (INCH/HOUR) 1 0.42 5.00 7.404 2 0.42 6.30 6.380 COMPUTED CONFLUENCE ESTIMATES ARE AS FOLLOWS: PEAK FLOW RATE(CFS) = 0.42 Tc(MIN.) = 6.30 TOTAL AREA(ACRES) = 0.2 LONGEST FLOWPATH FROM NODE 10.00 TO NODE 110.00 = 141.65 FEET. +--------------------------------------------------------------------------+ | POC-1 | | | | | +--------------------------------------------------------------------------+ ============================================================================ END OF STUDY SUMMARY: TOTAL AREA(ACRES) = 0.2 TC(MIN.) = 6.30 PEAK FLOW RATE(CFS) = 0.42 ============================================================================
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============================================================================ END OF RATIONAL METHOD ANALYSIS
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Chapter 3
References
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3.1 Methodology – Rational Method Peak Flow Determination
NOAA Atlas 14, Volume 6, Version 2
Location name: Carlsbad, California, USA*
Latitude: 33.1624°, Longitude: -117.3062°
Elevation: 356.33 ft**
* source: ESRI Maps ** source: USGS
POINT PRECIPITATION FREQUENCY ESTIMATES
Sanja Perica, Sarah Dietz, Sarah Heim, Lillian Hiner, Kazungu Maitaria, Deborah Martin, SandraPavlovic, Ishani Roy, Carl Trypaluk, Dale Unruh, Fenglin Yan, Michael Yekta, Tan Zhao, GeoffreyBonnin, Daniel Brewer, Li-Chuan Chen, Tye Parzybok, John Yarchoan
NOAA, National Weather Service, Silver Spring, Maryland
PF_tabular | PF_graphical | Maps_&_aerials
PF tabular
PDS-based point precipitation frequency estimates with 90% confidence intervals (in inches)1
Duration Average recurrence interval (years)
1 2 5 10 25 50 100 200 500 1000
5-min 0.129
(0.109‑0.155)
0.163
(0.137‑0.196)
0.211
(0.177‑0.254)
0.252
(0.210‑0.307)
0.312
(0.250‑0.393)
0.361
(0.283‑0.465)
0.413
(0.316‑0.547)
0.471
(0.349‑0.642)
0.554
(0.393‑0.790)
0.624
(0.426‑0.923)
10-min 0.185
(0.156‑0.222)
0.234
(0.197‑0.281)
0.303
(0.254‑0.365)
0.362
(0.301‑0.440)
0.447
(0.358‑0.563)
0.517
(0.405‑0.667)
0.592
(0.452‑0.784)
0.675
(0.500‑0.920)
0.795
(0.563‑1.13)
0.895
(0.611‑1.32)
15-min 0.224
(0.188‑0.268)
0.283
(0.238‑0.340)
0.366
(0.307‑0.441)
0.437
(0.363‑0.532)
0.541
(0.433‑0.681)
0.625
(0.490‑0.806)
0.716
(0.547‑0.948)
0.816
(0.605‑1.11)
0.961
(0.681‑1.37)
1.08
(0.739‑1.60)
30-min 0.317
(0.267‑0.380)
0.401
(0.337‑0.482)
0.518
(0.434‑0.624)
0.619
(0.515‑0.753)
0.766
(0.614‑0.965)
0.886
(0.694‑1.14)
1.01
(0.774‑1.34)
1.16
(0.856‑1.58)
1.36
(0.964‑1.94)
1.53
(1.05‑2.27)
60-min 0.439
(0.370‑0.527)
0.556
(0.468‑0.668)
0.719
(0.602‑0.866)
0.859
(0.714‑1.04)
1.06
(0.851‑1.34)
1.23
(0.962‑1.58)
1.41
(1.07‑1.86)
1.60
(1.19‑2.19)
1.89
(1.34‑2.69)
2.13
(1.45‑3.14)
2-hr 0.605
(0.509‑0.726)
0.756
(0.636‑0.908)
0.964
(0.808‑1.16)
1.14
(0.950‑1.39)
1.40
(1.12‑1.77)
1.61
(1.26‑2.08)
1.84
(1.40‑2.43)
2.08
(1.54‑2.84)
2.44
(1.73‑3.48)
2.74
(1.87‑4.06)
3-hr 0.722
(0.608‑0.866)
0.899
(0.756‑1.08)
1.14
(0.958‑1.38)
1.35
(1.12‑1.64)
1.65
(1.32‑2.08)
1.89
(1.48‑2.44)
2.15
(1.64‑2.85)
2.43
(1.80‑3.32)
2.84
(2.01‑4.05)
3.18
(2.17‑4.70)
6-hr 0.956
(0.805‑1.15)
1.20
(1.00‑1.44)
1.52
(1.27‑1.83)
1.79
(1.49‑2.18)
2.18
(1.75‑2.75)
2.49
(1.95‑3.21)
2.81
(2.15‑3.72)
3.16
(2.34‑4.31)
3.66
(2.59‑5.21)
4.06
(2.77‑6.00)
12-hr 1.23
(1.04‑1.48)
1.57
(1.32‑1.88)
2.01
(1.68‑2.42)
2.37
(1.97‑2.88)
2.87
(2.30‑3.62)
3.26
(2.56‑4.21)
3.67
(2.80‑4.85)
4.09
(3.03‑5.58)
4.68
(3.32‑6.67)
5.14
(3.51‑7.61)
24-hr 1.53
(1.35‑1.77)
1.97
(1.74‑2.28)
2.55
(2.24‑2.96)
3.02
(2.64‑3.53)
3.66
(3.09‑4.42)
4.15
(3.44‑5.11)
4.65
(3.77‑5.86)
5.17
(4.08‑6.69)
5.87
(4.45‑7.90)
6.42
(4.72‑8.93)
2-day 1.88
(1.65‑2.17)
2.44
(2.15‑2.82)
3.17
(2.79‑3.68)
3.77
(3.29‑4.41)
4.58
(3.87‑5.53)
5.20
(4.31‑6.40)
5.84
(4.73‑7.35)
6.49
(5.12‑8.40)
7.39
(5.60‑9.94)
8.09
(5.94‑11.2)
3-day 2.10
(1.85‑2.42)
2.73
(2.41‑3.16)
3.57
(3.13‑4.14)
4.25
(3.71‑4.97)
5.18
(4.38‑6.25)
5.90
(4.89‑7.27)
6.64
(5.38‑8.36)
7.40
(5.84‑9.58)
8.45
(6.41‑11.4)
9.26
(6.80‑12.9)
4-day 2.29
(2.02‑2.64)
2.99
(2.63‑3.46)
3.91
(3.44‑4.54)
4.67
(4.08‑5.47)
5.71
(4.83‑6.90)
6.52
(5.41‑8.03)
7.35
(5.95‑9.26)
8.21
(6.48‑10.6)
9.39
(7.12‑12.6)
10.3
(7.57‑14.3)
7-day 2.66(2.35‑3.07)3.51(3.09‑4.06)4.63(4.07‑5.37)5.55(4.84‑6.49)6.82(5.77‑8.23)7.81(6.48‑9.62)8.84(7.16‑11.1)9.90(7.81‑12.8)11.4(8.63‑15.3)12.5(9.21‑17.4)
10-day 2.94
(2.59‑3.40)
3.90
(3.44‑4.51)
5.17
(4.55‑6.01)
6.23
(5.43‑7.29)
7.69
(6.50‑9.28)
8.83
(7.32‑10.9)
10.0
(8.11‑12.6)
11.3
(8.88‑14.6)
13.0
(9.84‑17.5)
14.3
(10.5‑19.9)
20-day 3.58
(3.16‑4.14)
4.80
(4.23‑5.56)
6.43
(5.65‑7.47)
7.80
(6.80‑9.12)
9.71
(8.21‑11.7)
11.2
(9.30‑13.8)
12.8
(10.4‑16.1)
14.5
(11.4‑18.7)
16.8
(12.8‑22.7)
18.7
(13.8‑26.1)
30-day 4.26
(3.76‑4.93)
5.73
(5.05‑6.63)
7.72
(6.78‑8.96)
9.39
(8.19‑11.0)
11.7
(9.93‑14.2)
13.6
(11.3‑16.8)
15.6
(12.7‑19.7)
17.7
(14.0‑23.0)
20.8
(15.7‑27.9)
23.2
(17.0‑32.3)
45-day 5.06
(4.46‑5.85)
6.78
(5.98‑7.85)
9.14
(8.03‑10.6)
11.1
(9.72‑13.0)
14.0
(11.8‑16.9)
16.3
(13.5‑20.1)
18.8
(15.2‑23.6)
21.4
(16.9‑27.7)
25.2
(19.1‑34.0)
28.4
(20.8‑39.5)
60-day 5.87
(5.18‑6.79)
7.83
(6.90‑9.07)
10.5
(9.26‑12.2)
12.8
(11.2‑15.0)
16.2
(13.7‑19.5)
18.9
(15.7‑23.3)
21.8
(17.7‑27.5)
25.0
(19.7‑32.4)
29.6
(22.5‑39.9)
33.5
(24.6‑46.6)
1 Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS).
Numbers in parenthesis are PF estimates at lower and upper bounds of the 90% confidence interval. The probability that precipitation frequency estimates (for 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 are not
checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values.
Please refer to NOAA Atlas 14 document for more information.
Back to Top
PF graphical
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Maps & aerials
Small scale terrain
35
30
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C. Q) 20 "O
r:: 0 ·.;:; 15 <Q ..... 'a.
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5
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PDS-based depth-duration-frequency {DDF) curves
Latitude: 33.1624•, Longitude: -117 .. 3062°
........... i • - -•• ) .•••• .J ••• J • -••• ., •••••• ,_ •••• -~ •• - - • ~ ••• ,_ • .J -• -..... -·'-•••• -' ' . ' '
I t I I I , t , t I I t I ••• t ••• - • ; ••••• ·•, -.••• •.• •• ;. -••• • .••••• ·.• •••• -.-••• -• ; •• ·,-. ·, •• - • -.• -·.• •••
·····,····· ;•··,···,··
C: C: C: C: '-'-'-'-'->, >, >, >, >, >, >, .E .E .E .E .i;;;. .i;;;. .i;;;. .i;;;. .i;;;. <Q <Q <Q <Q <Q <Q <Q N m th I I "O "O "O "9 "O "O "O N r:!i I I I I .-1 N r/"Jtj-I I I 0 U"l 0 0 r-,. 0 0 0 .-1 .-1 l'fl '-0 .-1 N l'fl Duration
..........
····,----·-··
2 5 10 25 50 100 200 500
Average recurrence interval {years)
>, >,
<Q <Q
"O "O I I U"lO ,:;t'-0
1000
NOAA Atlas 14, Volume 6, Versio n 2 Created (GMT): Wed Apr 27 20:00:32 2022
Average recunenc-e
inte,val
(years)
2
5
10
25
50
100
200
500
1000
Duration
5-mln
10-,mln
15--mln
3-0-,mln
60-rnln
2-tlr
3-hr
6-tlr
12-hr
24-<hr
2-day
3-day
4-day
7-day
10-day
20-Clay
30-Clay
45-day
60-day
Large scale terrain
Large scale map
Large scale aerial
+
–
3km
2mi
+
–
100km
60mi
+
–
100km
60mi
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
Disclaimer
+
–
100km
60mi
Hydrologic Soil Group—San Diego County Area, California
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
4/27/2022
Page 1 of 4
36
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471459 471464 471469 471474 471479 471484 471489
471459 471464 471469 471474 471479 471484 471489
33° 9' 44'' N
11
7
°
1
8
'
2
2
'
'
W
33° 9' 44'' N
11
7
°
1
8
'
2
0
'
'
W
33° 9' 42'' N
11
7
°
1
8
'
2
2
'
'
W
33° 9' 42'' N
11
7
°
1
8
'
2
0
'
'
W
N
Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 11N WGS84
0 10 20 40 60
Feet
0 3 6 12 18
Meters
Map Scale: 1:219 if printed on A portrait (8.5" x 11") sheet.
Soil Map may not be valid at this scale.
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:
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 16, Sep 13, 2021
Soil map units are labeled (as space allows) for map scales
1:50,000 or larger.
Date(s) aerial images were photographed: Jan 24, 2020—Feb
12, 2020
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
4/27/2022
Page 2 of 4
Hydrologic Soil Group
Map unit symbol Map unit name Rating Acres in AOI Percent of AOI
MlC Marina loamy coarse
sand, 2 to 9 percent
slopes
B 0.1 100.0%
Totals for Area of Interest 0.1 100.0%
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
Hydrologic Soil Group—San Diego County Area, California
Natural Resources
Conservation Service
Web Soil Survey
National Cooperative Soil Survey
4/27/2022
Page 3 of 4
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
4/27/2022
Page 4 of 4