HomeMy WebLinkAboutCT 01-08; NORTH POINTE WEST; PRELIMINARY DRAINAGE STUDY; 2002-03-061
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K8rS ENGINEERING
Planning Engineering Surveying
CTo\-o8
PRELIMINARY DRAINAGE STUDY
FOR
NORTHPOINTE WEST
IN
CITY OF CARLSBAD
IN 00-111
March 6, 2002
48592 DATt I
7801 Mission Center C rt, Suite 100 • Son Diego, California 92108 • (619) 296-5565 • Fax (619) 296-5564
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TABLE OF CONTENTS
I.SITE DESCRIPTION -I 2.HYDROLOGY DESIGN MODELS I ~,i!'. INLET DESIGN • • • • • • • • • • • • • • • • • • • • • •• APPENDIX..,lIt 1!:0
~HYDROLOGIC CALCULATIONS .......................... APPENDIX~~
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5. TABLES AND CHARTS ................................ APPENDIX C
6. HYDROLOGY MAPS ................................... APPENDIX D
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1. SITE DESCRIPTION
A.
B.
EXISTING CONDITION
THE EXISTING SITE CONSISTS OF LOTS 9 THRU 12 OF MAP NO.
13716. THESE LOTS WERE MASS-GRADED PER CITY OF CARLSBAD
PROJECT NO. 98-07, GRADING PLAN NO. 365-SA.
THE GRADED PADS CURRENTLY DRAIN IN AN INTERIM CONDITION
TO AN EXISTING DESILTING BASIN LOCATED ON THE SOUTHERLY
SIDE OF LOT NO. 12. THESE COMBINED STORM FLOWS ARE
CONVEYED FROM THE DESILTING BASIN BY ·AN EXISTING 48"
STORM DRAIN TO AN EXISTING CREEK THAT RUNS ALONG THE
WESTERLY SUBDIVISION BOUNDARY.
STORM FLOWS ALSO ENTER THIS BASIN VIA AN UNDERGROUND
STORM DRAIN SYSTEM FROM THE EXISTING NORTHPOINTE
DEVELOPMENT. APROXIMATELY 13.5 ACRES ARE TRIBUTARY TO
THIS STORM DRAIN SYSTEM. THE EXISTING STORM DRAIN
SYSTEM UTILIZES FOSSIL FILTERS AT ALL CATCH BASINS AND
INLETS TO TREAT THE STORM RUNOFF BEFORE ENTERING THE
EXISTING DESILT BASIN.
ALSO, LOTS 9, 10 AND 11 CONTAIN INDIVIDUAL 24" STORM
DRAIN PIPES CONSTRUCTED PER SAID GRADING PLAN NO. 365-
A. THESE INDIVIDUAL STORM DRAINS. DO NOT ACCEPT FLOWS
IN THE INTERIM CONDITION, BUT ARE INTENDED FOR THE USE
BY THE PROPOSED DEVELOPMENT.
PROPOSED CONDITION
THE PROPOSED SITE (NORTHPOINTE" WEST) CONSISTS OF
INDUSTRIAL BUILDINGS AND THEIR CORRESPONDING PARKING
AREAS. THE PROPOSED DRAINAGE CONSISTS OF A COMBIN;ATTON
OF SURFACE FLOW AND A SYSTEM OF INLETS AND UNDERGROUND.
PIPES THAT WILL TIE INTO THE FOUR EXISTING STORM DRAIN
PIPES MENTIONED ON THE "EXISTING CONDITION" AND CONVEY
THE PROPOSED FLOWS TO THE EXISTING CREEK. ALL CATCH
BASINS AND INLETS PROPOSED WITH THIS PROJECT WILL HAVE
FOSSIL FILTERS INSTALLED.
ALSO, A SEPARATE REPORT ENTITLED "CONCEPT WATER QUALITY
PLAN" HAS BEEN PREPARED FOR THE PROJECT. THIS REPORT
ADDRESSES THE SAN DIEGO REGIONAL WATER QUALITY "BOARD
ORDER 2001.01. BRIEFLY, THE REPORT DEMONSTRATES THAT
THERE WILL BE NO DOWNSTREAM IMPACTS DUE TO DEVELOPMENT
OF THE SITE WITH RESPECT TO WATER QUALITY AND EROSION.
A MAINTENANCE PROGRAM FOR THE BMP'S HAS ALSO BEEN
ADDRESSED IN THE REPORT.
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2. HYDROLOGY DESIGN MODELS
A. DESIGN METHODS
THE RATIONAL METHOD IS USED IN THIS HYDROLOGY STUDY; THE RATIONAL
FORMULA IS AS FOLLOWS:
Q = CIA, WHERE : Q= PEAK DISCHARGE IN CUBIC FEET/SECOND *
C = RUNOFF COEFFICIENT (DIMENSIONLESS)
I = RAINFALL INTENSITY IN INCHES/HOUR (PER APPENDIX XI-A)
A = TRIBUTARY DRAINAGE AREA IN ACRES
*1 ACRE INCHES/HOUR = 1.008 CUBIC FEET/SEC
THE NATURAL WATERSHED METHOD IS ALSO USED IN THIS HYDROLOGY STUDY;
THE NATURAL WATERSHED FLOW FORMULA IS AS FOLLOWS:
B.
C.
Tc=1. 8 (1.1-C) (L) .5/ [S (100)] .333
L = OVERLAND TRAVEL DISTANCE IN FEET
S = SLOPE IN FT./FT.
Tc= TIME IN MINUTES
DESIGN CRITERIA
-FREQUENCY, 100 YEAR STORM.
-LAND USE PER SPECIFIC PLAN AND TENTATIVE MAP.
-RAIN FALL INTENSITY PER COUNTY OF SAN DIEGO 1993 HYDROLOGY
DESIGN MANUAL.
REFERENCES
COUNTY OF SAN DIEGO 1993, HYDROLOGY MANUAL.
-COUNTY OF SAN DIEGO 1992 REGIONAL STANDARD DRAWING.
-HAND BOOK OF HYDRAULICS BY BRATER & KING, SIXTH EDITION.
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I APPENDIX A
(3. HYDROLOGY CALCULATIONS)
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EXISTING HYDROLOGY
San Diego County Rational Hydrology Program
CIVILCADD/CIVILDESIGN Engineering Software, (c)1991-2001 Version 6.2
Rational method hydrology program based on
San Diego County Flood Control Division 1985 hydrology manual
Rational Hydrology Study Date: 02/12/02
********* Hydrology Study Control Information **********
---------------------------------------------------~--------------------
K & S Engineering, San Diego, California -SiN 868
Rational hydrology study storm event year is
English (in-lb) input data Units used
English (in) rainfall data used
Map data precipitation entered:
6 hour, precipitation (inches) = 2.600
24 hour precipitation(inches) 4.200
Adjusted 6 hour precipitation (inches) = 2.600
P6/P24 = 61.9%
San Diego hydrology manual 'C' values used
Runoff coefficients by rational method
100.0
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 1.000 to Point/Station 2.000
**** INITIAL AREA EVALUATION ****
User specified 'C' value of 0.450 given for subarea
Initial subarea flow distance 365.000(Ft.)
Highest elevation = 276.000(Ft.)
Lowest elevation = 270.000(Ft.)
Elevation difference = 6.000(Ft.)
Time of concentration calculated by the urban
areas overland flow method (App X-C) = 18.94 min.
TC = [l.8*(1.1-C)*distance(Ft.)A.5)/(% slopeA (1/3»)
TC = [1.8*(1.1-0.4500)*( 365.000A.5)/( 1.644A(1/3»)= 18.94
Rainfall intensity (I) = 2.902 (In/Hr) for a 100.0 year storm
Effective runoff coefficient used for area (Q=KCIA) is C = 0.450
Subarea runoff = 3.055(CFS)
Total initial stream area = 2.340(Ac.)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 2.000 to Point/Station 3.000
**** IMPROVED CHANNEL TRAVEL TIME ****
Upstream point elevation = 270.000(Ft.)
Downstream point elevation 263.500(Ft.)
Channel length thru subarea 250.000(Ft.)
Channel base width 1.000(Ft.)
Slope or 'Z' of left channel bank =
Slope or 'Z' of right channel bank =
Manning's 'N' = 0.020
2.000
2.000
Maximum depth of channel 1.000(Ft.)
Flow(q) thru subarea = 3.055(CFS)
Depth of flow = 0.373(Ft.), Average velocity
Channel flow top width = 2.494(Ft.)
Flow Velocity = 4.68(Ft/s)
4.683(Ft/s)
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Travel time 0.89 min.
Time of concentration 19.83 min.
Critical depth = 0.484(Ft.)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 2.000 to Point/Station 3.000
**** SUBAREA FLOW ADDITION ****
User specified 'c' value
Time of concentration =
of 0.450 given for subarea
19.83 min.
Rainfall intensity
Runoff coefficient
Subarea runoff
Total runoff =
2.817 (In/Hr) for a 100.0 year storm
used for sub-area, Rational method,Q=KCIA, C
2.662(CFS) for 2.100(Ac.)
5.717(CFS) Total area = 4.44 (Ac.)
0.450
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 3.000 to Point/Station 4.000
**** IMPROVED CHANNEL TRAVEL TIME ****
Upstream point elevation = 263.500(Ft.)
Downstream point elevation 260.000(Ft.)
Channel length thru subarea 310.000(Ft.)
Channel base width 1.000(Ft.)
Slope or 'Z' of left channel bank =
Slope or 'Z' of right channel bank =
Manning's 'N' = 0.020
2.000
2.000
Maximum depth of channel 1.000(Ft.)
F1ow(q) thru subarea = 5.717(CFS)
Depth of flow = 0.624(Ft.), Average velocity
Channel flow top width = 3.498(Ft.)
Flow Velocity = 4.07(Ft/s)
Travel time 1.27 min.
Time of concentration 21.10 min.
Critical depth = 0.664(Ft.)
4.071(Ft/S)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 3.000 to Point/Station 4.000
**** SUBAREA FLOW ADDITION ****
User specified 'C' value of 0.450 given for subarea
Time of concentration = 21.10 min.
Rainfall intensity 2.706(In/Hr) for a 100.0 year storm
Runoff coefficient used for sub-area, Rational method,Q~KCIA, C -0.450
Subarea runoff 3.276(CFS) for 2.690(·Ac.)
Total runoff = 8.994(CFS) Total area = 7.13(Ac.)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 4.000 to Point/Station 5.000
**** IMPROVED CHANNEL TRAVEL TIME ****
Upstream point elevation = 260.000(Ft.)
Downstream point elevation 251.000(Ft.}
Channel length thru subarea 320.000(Ft.)
Channel base width 45.000(Ft.) .
Slope or 'Z' of left channel bank = 2.000
Slope or 'Z' of right channel bank = 2.000
Manning's 'N' = 0.020
Maximum depth of channel
Flow(q) thru subarea =
10.000 (Ft.)
8.994(CFS}
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Depth of flow = 0.084(Ft.), Average velocity
Channel flow top width = 45.335(Ft.)
Flow Velocity = 2.38(Ft/s)
Travel time 2.24 min.
Time of concentration 23.34 min.
Critical depth = 0.107(Ft.)
2.378(Ft/s)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 4.000 to Point/Station 5.000
**** SUBAREA FLOW ADDITION ****
User specified 'e' value
Time of concentration =
of 0.450 given for subarea
23.34 min.
Rainfall intensity
Runoff coefficient
Subarea runoff
Total runoff =
2.536(In/Hr) for a 100.0 year storm
used for sub-area, Rational method,Q=KCIA, C
3.195(CFS) for 2.800(Ac.)
12.188(CFS) Total area = 9.93(Ac.)
0.450
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 4.000 to Point/Station 5.000
**** CONFLUENCE OF MINOR STREAMS ****
Along Main Stream number: 1 in normal stream number 1
Stream flow area = 9.930(Ac.)
Runoff from this stream = 12.188(CFS)
Time of concentration 23.34 min.
Rainfall intensity = 2.536(In/Hr)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 303.000 to Point/Station 6.000
**** USER DEFINED FLOW INFORMATION AT A POINT ****
Decimal fraction soil group A
Decimal fraction soil group B
Decimal fraction soil group e
Decimal fraction soil group D
[INDUSTRIAL area type
0.000
0.000
0.000
1.000
Rainfall intensity (I) = 4.843(In/Hr) for a
User specified values are as follows:
100.0 year storm
TC = 8.56 min. Rain intensity = 4.84 (In/Hr)
Total area = 14.740(Ac.) Total runoff = 72.684(CFS)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 6.000 to Point/Station 5.000
**** PIPEFLOW TRAVEL TIME (User specified size) ****
Upstream point/station elevation = 254.670(Ft.)
Downstream point/station elevation 252.270(Ft.)
Pipe length 177.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow 72.684(CFS)
Given pipe size = 36.00(In.)
Calculated individual pipe flow 72.684(CFS)
Normal flow depth in pipe = 27.61(In.)
Flow top width inside pipe = 30.44(In.)
Critical Depth = 32.32(In.)
Pipe flow velocity = 12.49(Ft/s)
Travel time through pipe = 0.24 min.
Time of concentration (Te) = 8.80 min.
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++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 6.000 to Point/Station 5.000
**** CONFLUENCE OF MINOR STREAMS ****
Along Main Stream number: 1 in normal stream number 2
Stream flow area = 14.740(Ac.)
Runoff from this stream 72.684(CFS)
Time of concentration =
Rainfall intensity =
Summary of stream data:
8.80 min.
4.759(In/Hr)
Stream
No.
Flow rate
(CFS)
TC
(min)
Rainfall Intensity
(In/Hr)
1 12.188 23.34 2.536
2 72.684 8.80 4.759
Qmax(l)
1.000 * 1.000 * 12.188) +
0.533 * 1.000 * 72.684) + 50.920
Qmax(2)
1.000 * 0.377 * 12.188) +
1.000 * 1.000 * 72.684) + 77.277
Total of 2 streams to confluence:
Flow rates before confluence point:
12.188 72.684
Maximum flow rates at confluence using above data:
50.920 77.277
Area of streams before confluence:
9.930 14.740
Results of confluence:
Total flow rate = 77.277(CFS)
Time of concentration 8.796 min.
Effective stream area after confluence 24.670(Ac.)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 5.000 to Point/station 7.000
**** PIPEFLOW TRAVEL TIME (User specified size) ****
Upstream pOint/station elevation = 247.000(Ft.)
Downstream point/station elevation 246.800(Ft.)
Pipe length 20.00(Ft.) Manning's N = 0.024
No. of pipes = 1 Required pipe flow 77.277(CFS)
Given pipe size = 36.00(In.)
NOTE: Normal flow is pressure flow in user selected pipe size.
The approximate hydraulic grade line above the pipe invert is
3.499(Ft.) at the headworks or inlet of the pipe(s)
Pipe friction loss = 0.915(Ft.)
Minor friction loss = 2.784(Ft.) K-factor = 1.50
Pipe flow velocity = 10.93(Ft/s)
Travel time through pipe 0.03 min.
Time of concentration (TC) = 8.83 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 7.000 to Point/Station 8.00b
**** PIPEFLOW TRAVEL TIME (User specified size) ****
Upstream point/station elevation =
Downstream point/station elevation
246.470(Ft.)
221.620(Ft.)
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Pipe length 46.7S(Ft.) Manning's N = 0.013
No. of pipes 1 Required pipe flow 77.277(CFS)
Given pipe size = 36.00(In.)
Calculated individual pipe flow 77.277(CFS)
Normal flow depth in pipe = 9.70(In.)
Flow top width inside pipe = 31.9S(In.)
Critical Depth = 32.93(In.)
Pipe flow velocity = SO.31(Ft/s)
Travel time through pipe = 0.02 min.
Time of concentration (TC) = 8.84 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 8.000 to Point/Station 9.000
**** PIPEFLOW TRAVEL TIME (User specified size) ****
Upstream point/station elevation = 220.620(Ft.)
Downstream point/station elevation 220.260(Ft.)
Pipe length 3S.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow 77.277(CFS)
Given pipe size = 48.00(In.)
Calculated individual pipe flow 77.277(CFS)
Normal flow depth in pipe = 24.84(In.)
Flow top width inside pipe = 47.97(In.)
Critical Depth = 31.91(In.)
Pipe flow velocity = 11.76(Ft/s)
Travel time through pipe = O.OS min.
Time of concentration (TC) = 8.89 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 8.000 to Point/Station 9.000
**** SUBAREA FLOW ADDITION ****
User specified 'c' value
Time of concentration =
of 0.4S0 given for subarea
8.89 min.
Rainfall intensity
Runoff coefficient
Subarea runoff
Total runoff =
4.72S(In/Hr) for a 100.0 year storm
used for sub-area" Rational method,Q=KCIA, C
2.SS2(CFS) for 1.200(Ac.)
79.829(CFS) Total area = 25.87(Ac.)
0.4S0
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 9.000 to Point/Station 10.,000
**** PIPEFLOW TRAVEL TIME (User specified size) ****
Upstream point/station elevation = 220.260(Ft.)
Downstream point/station elevation 220.200(Ft.)
Pipe length 3S.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow 79.829(CFS)
Given pipe size = 48.00(In.)
NOTE: Normal flow is pressure flow in user selected pipe size.
The approximate hydraulic grade line above the pipe invert is
0.988(Ft.) at the headworks or inlet of the pipe(s)
Pipe friction loss = 0.108(Ft.)
Minor friction loss = 0.940(Ft.) K-factor = 1.S0
Pipe flow velocity = 6.3S(Ft/s)
Travel time through pipe 0.09 min.
Time of concentration (TC) 8.98 min.
End of computations, total study area = 2S.870 (Ac.)
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PROPOSED CONDITION
San Diego County Rational Hydrology Program
CIVILCADD/CIVILDESIGN Engineering Software, (c)1991-2001 Version 6.2
Rational method hydrology program based on
San Diego County Flood Control Division 1985 hydrology manual
Rational Hydrology Study Date: 12/18/01
********* Hydrology Study Control Information **********
K & S Engineering, San Diego, California -SiN 868
Rational hydrology study storm event year is
English (in-lb) input data Units used
English (in) rainfall data used
Map data precipitation entered:
6 hour, precipitation (inches) = 2.600
24 hour precipitation(inches) 4.200
Adjusted 6 hour precipitation (inches) = 2.600
P6/P24 = 61.9%
San Diego hydrology manual 'C' values used
Runoff coefficients by rational method
100.0
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 1.000 to Point/Station 2.000
**** INITIAL AREA EVALUATION ****
Decimal fraction soil group A 0.000
Decimal fraction soil group B 0.000
Decimal fraction soil group C 0.000
Decimal fraction soil group D 1.000
[INDUSTRIAL area type ]
Initial subarea flow distance 400.000(Ft.)
Highest elevation = 275.560(Ft.)
Lowest elevation = 270.170(Ft.)
Elevation difference = 5.390(Ft.)
Time of concentration calculated by the urban
areas overland flow method (App X-C) = 4.89 min.
TC = [1.8*(1.1-C)*distance(Ft.)A.5)/(% slopeA(1/3)]
TC = [1.8*(1.1-0.9500)*( 400.000A.5)/( 1.347A(1/3)]= 4.89
Setting time of concentration to 5 minutes
Rainfall intensity (I) = 6.850(In/Hr) for a 100.0 year storm
Effective runoff coefficient used for area (Q=KCIA) is C = 0.950
Subarea runoff = 7.159(CFS)
Total initial stream area = 1.100(Ac.)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 1.000 to Point/Station 2.000
**** CONFLUENCE OF MINOR STREAMS ****
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Along Main Stream number: 1 in normal stream number 1
Stream flow area = 1.100(Ac.)
Runoff from this stream 7.159(CFS)
Time of concentration 5.00 min.
Rainfall intensity = 6.850(In/Hr)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 20.000 to Point/Station 21.000
**** INITIAL AREA EVALUATION ****
Decimal fraction soil group A
Decimal fraction soil group B
Decimal fraction soil group C
Decimal fraction soil group D
[INDUSTRIAL area type
0.000
0.000
0.000
1.000
Initial subarea flow distance
Highest elevation = 273.040(Ft.)
Lowest elevation = 269.570(Ft.)
]
160.000(Ft.)
Elevation difference = 3.470(~t.)
Time of concentration calculated by the urban
areas overland flow method (App X-C) = 2.64 min.
TC = [1.8*(1.1-C)*distance(Ft.)A.5)/(% slopeA(1/3)]
TC = [1.8*(1.1-0.9500)*( 160.000A.5)/( 2.169A(1/3)]=
Setting time of concentration to 5 minutes
2.64
Rainfall intensity (I) = 6.850(In/Hr) for a 100.0 year storm
Effective runoff coefficient used for area (Q=KCIA) is C = 0.950
Subarea runoff = 8.330(CFS)
Total initial stream area = 1.280(Ac.)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 21.000 to Point/Station 2.000
**** PIPEFLOW TRAVEL TIME (User specified size) ****
Upstream point/station elevation = 266.070(Ft.)
Downstream point/station elevation 258.300(Ft.)
Pipe length 114.50(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow 8.330(CFS)
Given pipe size = 12.00(In.)
Calculated individual pipe flow 8.330(CFS)
Normal flow depth in pipe = 8.88(In.)
Flow top width inside pipe = 10.52(In.)
Critical depth could not be calculated.
Pipe flow velocity = 13.37(Ft/s)
Travel time through pipe 0.14 min.
Time of concentration (TC) = 5.14 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 21.000 to Point/Station 2.000
**** CONFLUENCE OF MINOR STREAMS ****
Along Main Stream number: 1 in normal stream number 2
Stream flow area = 1.280(Ac.)
Runoff from this stream 8.330(CFS)
Time of concentration = 5.14 min.
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Rainfall intensity = 6.727(In/Hr)
Summary of stream data:
Stream Flow rate TC Rainfall Intensity
No. (CFS) (min) (In/Hr)
1 7.159 5.00 6.850
2 8.330 5.14 6.727
Qmax(l)
1. 000 * 1. 000 * 7.159) +
1. 000 * 0.972 * 8.330) + 15.257
Qmax(2)
0.982 * 1. 000 * 7.159) +
1. 000 * 1. 000 * 8.330) + 15.360
Total of 2 streams to confluence:
Flow rates before confluence point:
7.159 8.330
Maximum flow rates at confluence using above data:
15.257 15.360
Area of streams before confluence:
1.100 1.280
Results of confluence:
Total flow rate = 15.360(CFS)
Time of concentration 5.143 min.
Effective stream area after confluence 2.380(Ac.)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++t+++++++
Process from Point/Station 2.000 to Point/Station j.OOO
**** PIPEFLOW TRAVEL TIME (User specified size) ****
Upstream point/station elevation = 258.550(Ft.)
Downstream point/station elevation 241.200(Ft.)
Pipe length 60.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow 15.360(CFS)
Given pipe size = 24.00(In.)
Calculated individual pipe flow 15.360(CFS)
Normal flow depth in pipe = 5.76(In.)
Flow top width inside pipe = 20.50(In.)
Critical Depth = 16.95(In.)
Pipe flow velocity = 26.50(Ft/s)
Travel time through pipe = 0.04 min.
Time of concentration (TC) = 5.18 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 1.000 to Point/Station 4.000
**** INITIAL AREA EVALUATION ****
Decimal fraction soil group A 0.000
Decimal fraction soil group B 0.000
Decimal fraction soil group C 0.000
Decimal fraction soil group D 1.000
[INDUSTRIAL area type ]
Initial subarea flow distance 500.000(Ft.)
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Highest elevation = 275.560(Ft.)
Lowest elevation = 267.500(Ft.)
Elevation difference = 8.060(Ft.)
Time of concentration calculated by the urban
areas overland flow method (App X-C) = 5.15 min.
TC = [1.8*(1.1-C)*distance(Ft.)~.5)/(% slope~(1/3)]
TC = [1.8*(1.1-0.9500)*( 500.000~.5)/( 1.612~(1/3)]= 5.15
Rainfall intensity (I) = 6.722(In/Hr) for a 100.0 year storm
Effective runoff coefficient used for area (Q=KCIA) is C = 0.950
Subarea runoff = 13.091(CFS)
Total initial stream area = 2.050 (Ac. )
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 4.000 to Point/Station 5.000
**** IMPROVED CHANNEL TRAVEL TIME ****
Upstream point elevation = 267.500(Ft.)
Downstream point elevation 265.220(Ft.)
Channel length thru subarea 200.000(Ft.)
Channel base width O.OOO(Ft.)
Slope or 'Z'. of left channel bank = 67.000
Slope or 'Z' of right channel bank = 67.000
Estimated mean flow rate at midpoint of channel 16.156(CFS)
Manning's 'N' = 0.015
Maximum depth of channel 1.000(Ft.)
Flow(q) thru subarea = 16.156(CFS)
Depth of flow = 0.288(Ft.), Average velocity 2.906(Ft/s)
Channel flow top width = 38.599(Ft.)
Flow Velocity = 2.91(Ft/s)
Travel time 1.15 min.
Time of concentration = 6.30 min.
Critical depth = 0.324(Ft.)
Adding area flow to channel
Decimal fraction soil group A 0.000
Decimal fraction soil group B 0.000
Decimal fraction soil group C 0.000
Decimal fraction soil group D 1.000
[INDUSTRIAL area type
Rainfall intensity 5.904(In/Hr) for a 100.0 year storm
Runoff coefficient used for sub-area, Rational method,Q=KCIA, C 0.950
Subarea runoff 5.384(CFS) for 0.960(Ac.)
Total runoff = 18.475(CFS) Total area = 3.01(Ac.)
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++t++++++
Process from Point/Station 5.000 to Point/Station 6.000
**** PIPEFLOW TRAVEL TIME (User specified size) ****
Upstream point/station elevation = 262.050(Ft.)
Downstream point/station elevation 251.500(Ft.)
Pipe length 46.20(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow 18.475(CFS)
Given pipe size = 15.00(In.)
Calculated individual pipe flow 18.475(CFS)
Normal flow depth in pipe = 8.36(In.)
Flow top width inside pipe = 14.90(In.)
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Critical depth could not
Pipe flow velocity =
be calculated.
26.28 (Ft/s)
0.03 min. Travel time through pipe
Time of concentration (TC) = 6.33 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 6'.000 to Point/Station 7.000
**** PIPEFLOW TRAVEL TIME (User specified size) ****
Upstream,point/station elevation = 251.170(Ft.)
Downstream point/station elevation 234.200(Ft.)
Pipe length 55.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow 18.475(CFS)
Given pipe size = 24.00(In.)
Calculated individual pipe flow l8.475(CFS)
Normal flow depth in pipe = 6.22(In.)
Flow top width inside pipe = 21.03(In.)
Critical Depth = l8.58(In.)
Pipe flow velocity = 28.60(Ft/s)
Travel time through pipe = 0.03 min.
Time of concentration (TC) = 6.36 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 8.000 to Point/Station 9.000
**** INITIAL AREA EVALUATION ****
Decimal fraction soil group A
Decimal fraction soil group B
Decimal fraction soil group C
Decimal fraction soil group D
[INDUSTRIAL area type
0.000
0.000
0.000
1. 000
Initial subarea flow distance
Highest elevation = 269.500(Ft.)
Lowest elevation = 261.670(Ft.)
]
500 . 000 (Ft. )
Elevation difference = 7.830(Ft.)
Time of concentration calculated by the urban
areas overland flow method (App X-C) = 5.20 min.
TC = [1.8*(1.1-C)*distance(Ft.)A.5)/(% slopeA(1/3)]
TC = [1.8*(1.1-0.9500)*( 500.000A.5)/( 1.566A(l/3)]= 5.20
Rainfall intensity (I) = 6. 680 (In/Hr) for a 100.0 year storm
Effective runoff coefficient used for area (Q=KCIA) is C = 0.950
Subarea runoff = 19.927(CFS)
Total initial stream area = 3.140(Ac.)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 9.000 to Point/Station 10.000
**** PIPEFLOW TRAVEL TIME (User specified size) ****
Upstream point/station'el'evation = ?58.500(Ft.)
Downstream point/station elevation 248.000(Ft.)
Pipe length 78.30(Ft.) Manning's N = 0.015
No. of pipes = 1 Required pipe flow 19.927(CFS)
Given pipe size = 18.00(In.)
Calculated individual pipe flow 19.927(CFS)
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Normal flow depth in pipe 10.03(In.)
Flow top width inside pipe = 17.88(In.)
Critical depth could not be calculated.
Pipe flow velocity = 19.71(Ft/s)
Travel time through pipe 0.07 min.
Time of concentration (TC) = 5.27 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 9.000 to Point/Station 10.000
**** SUBAREA FLOW ADDITION ****
Decimal fraction soil group A 0.000
Decimal fraction soil group B 0.000
Decimal fraction soil group C 0.000
Decimal fraction soil group D 1.000
[INDUSTRIAL area type
Time of concentration 5.27 min.
Rainfall intensity 6.626(In/Hr) for a 100.0 year storm
Runoff coefficient used for sub-area, Rational method,Q=KCIA, C 0.950
Subarea runoff 1.259(CFS) for 0.200(Ac.)
Total runoff = 21.185(CFS) Total area = 3.34(Ac.)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 10.000 to Point/Station 11.000
**** PIPEFLOW TRAVEL TIME (User specified size) ****
Upstream point/station elevation = 246.950(Ft.)
Downstream point/station elevation 230.800(Ft.)
Pipe length 90.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow 21.185(CFS)
Given pipe size = 24.00(In.)
Calculated individual pipe flow 21.185(CFS)
No~mal flow depth in pipe = 7.66(In.)
Flow top width inside pipe = 22.38(In.)
Critical Depth = 19.78(In.)
Pipe flow velocity = 24.49(Ft/s)
Travel time through pipe = 0.06 min.
Time of concentration (TC) = 5.33 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 12.000 to Point/Station 13.000
**** USER DEFINED FLOW INFORMATION AT A POINT ****
Decimal fraction soil group A 0.000
Decimal fraction soil group B 0.000
Decimal fraction soil group C 0.000
Decimal fraction soil group D 1.000
[INDUSTRIAL area type I
Rainfall intensity (I) = 4.844(In/Hr) for a 100.0 year storm
User specified values are as follows:
TC = 8.56 min. Rain intensity = 4.84(In/Hr)
Total area = 14.740(Ac.) Total runoff = 72.684(CFS)
. .
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++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 13.000 to Point/Station 14.000
**** PIPEFLOW TRAVEL TIME (User specified size) ****
Upstream point/station elevation = 254.670(Ft.)
Downstream point/station elevation 253.840(Ft.)
Pipe length 85.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow 72.684(CFS)
Given pipe size = 36.00(In.)
NOTE: Normal flow is pressure flow in user selected pipe size.
The approximate hydraulic grade line above the pipe invert is
2.642(Ft.) at the headworks or inlet of the pipe(s)
Pipe friction loss = 1.009(Ft.)
Minor friction loss = 2.463(Ft.) K-factor = 1.50
Pipe flow velocity = 10.28(Ft/s)
Travel time through pipe 0.14 min.
Time of concentration (TC) = 8.69 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 13.000 to Point/Station 14.000
**** SUBAREA FLOW ADDITION ****
Decimal fraction soil group A 0.000
Decimal fraction soil group B 0.000
Decimal fraction soil group C 0.000
Decimal fraction soil group D 1.000
[INDUSTRIAL area type
Time of concentration 8.69 min.
Rainfall intensity 4.795(In/Hr) for a 100.0 year storm
Runoff coefficient used for sub-area, Rational method,Q=KCIA, C 0.950
Subarea runoff 1.822(CFS) for 0.400(Ac.)
Total runoff = 74.506(CFS) Total area = 15.14(Ac.)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 14.000 to Point/Station 15.000
**** PIPEFLOW TRAVEL TIME (User specified size) ****
Upstream point/station elevation = 253.840(Ft.)
Downstream point/station elevation 251.890(Ft.)
Pipe length 110.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow 74.506(CFS)
Given pipe size = 36.00(In.)
Calculated individual pipe flow 74.506(CFS)
Normal flow depth in pipe = 25.24(In.)
Flow top width inside pipe = 32.96(In.)
Critical Depth = 32.54(In.)
Pipe flow velocity = 14.07(Ft/s)
Travel time through pipe = 0.13 min.
Time of concentration (TC) = 8.82 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 14.000 to Point/Station 15.000
**** SUBAREA FLOW ADDITION ****
..-_I
!-
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Decimal fraction soil
Decimal fraction soil
Decimal fraction soil
Decimal fraction soil
[INDUSTRIAL area type
group
group
group
group
A 0.000
B 0.000
C 0.000
D 1.000
Time of concentration 8.82 min.
Rainfall intensity 4.749(In/Hr) for a 100.0 year storm
Runoff coefficient used for sub-area, Rational method,Q=KCIA, C 0.950
Subarea runo.ff 1. 714 (CFS) for 0.380 (Ac.)
Total runoff = 76.220(CFS) Total area = 15.52(Ac.)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 15.000 to Point/Station 16.000
**** PIPEFLOW TRAVEL TIME (User specified size) ****
Upstream point/station elevation = 251.890(Ft.)
Downstream point/station elevation 246.800(Ft.)
Pipe length 24.80(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow 76.220(CFS)
Given pipe size = 36.00(In.)
Calculated individual pipe flow 76.220(CFS)
Normal flow depth in pipe = 12.33(In.)
Flow top width inside pipe = 34.17(In.)
Critical Depth = 32.77(In.)
Pipe flow velocity = 35.63(Ft/s)
Travel time through pipe = 0.01 min.
Time of concentration (TC) = 8.84 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 16.000 to Point/Station 17.000
**** PIPEFLOW TRAVEL TIME (User specified size) ****
Upstream point/station elevation = 246.470(Ft.)
Downstream point/station elevation 221.620(Ft.)
Pipe length 46.75(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow 76.220(CFS)
Given pipe size = 36.00(In.)
Calculated individual pipe flow 76.220(CFS)
Normal flow depth in pipe = 9.63(In.)
Flow top width inside pipe = 31.87(In.)
Critical Depth = 32.77(In.)
Pipe flow velocity = 50.10(Ft/s)
Travel time through pipe = 0.02 min.
Time of concentration (TC) = 8.85 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station. 17.0DO to Point/Station 18.000
**** PIPEFLOW TRAVEL TIME (User specified size) ****
Upstream point/station elevation = 220.620(Ft.)
Downstream point/station elevation 220.260(Ft.)
Pipe length 35.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow 76.220(CFS)
Given pipe size = 48.00(In.)
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Calculated individual pipe flow 76.220(CFS)
Normal flow depth in pipe = 24.66(In.)
Flow top width inside pipe = 47.98(In.)
Critical Depth = 31.69(In.)
Pipe flow velocity = 11.72(Ft/s)
Travel time through pipe = 0.05 min.
Time of concentration (TC) = 8.90 min.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 17.000 to Point/Station 18.000
**** SUBAREA FLOW ADDITION ****
Decimal fraction soil group A 0.000
Decimal fraction soil group B 0.000
Decimal fraction soil group C 0.000
Decimal fraction soil group D 1.000
[INDUSTRIAL area type
Time of concentration 8.90 min.
Rainfall intensity 4.722(In/Hr) for a 100.0 year storm
Runoff coefficient used for sub-area, Rational method,Q=KCIA, C 0.950
Subarea runoff 6.640(CFS) for 1.480(Ac.)
Total runoff = 82.860(CFS) Total area = 17.00(Ac.)
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Process from Point/Station 18.000 to Point/Station 19.000
**** PIPEFLOW TRAVEL TIME (User specified size) ****
Upstream point/station elevation = 220.260(Ft.)
Downstream point/station elevation 219.970(Ft.)
Pipe length 35.00(Ft.) Manning's N = 0.013
No. of pipes = 1 Required pipe flow 82.860(CFS)
Given pipe size = 48.00(In.)
Calculated individual pipe flow 82.860(CFS)
Normal flow depth in pipe = 27.75(In.)
Flow top width inside pipe = 47.41(In.)
Critical Depth = 33.11(In.)
Pipe flow velocity = 11.02(Ft/s)
Travel time through pipe = 0.05 min.
Time of concentration (TC) 8.95 min.
End of computations, total study area = 25.730 (Ac.)
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APPENDIX B
I (4. INLET DESIGN)
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, I ~ R;tJ?'~!J / tV t. €r" De-..$'/~,-./
t-_: /l/cpe:it (q"&Aer# ~)
. -&100 ::z. f,g tJ¢5 l -rUlO SIDeS' v~/lQI/-rrI!!fG
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I
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______ L/~~:::..:...r-=-r:r.~. -=-= :2 +:_.2 :=--< I (/lUI/IV.:)O ~ CL,O~'//I/' ) 11 __________________ 2 __ > ____________________________ ' ____ _
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f. :z /,°9:5 / I ff
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1------------,
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.' I ;. ..
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I APPENDIX C
(5. TABLES AND CHARTS)
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/1)1)
URB/lAl /lRE/l.5 OYERL/1NiJ TIME ()F FLtJW CURVES
v
ITT
E.comp/4:
6'iY~n : L l!A9;h tJI Flow • 3()" /r.
S/Opt!" • /, tJ %
C()~/h~i~/11 0/ Runo/'/. C· .SO
R~ad: ()y~~/~hr/ /7pwhm~ ,Io? Al/nv/I!".S'
SAN DIEGO COUNTY
DEPARTMENT OF SPECIAL DISTRICT SE RVICES
'" I:' ~ I "I., U 1\ t\l11 A L
7.
-T
.0 . _ -
. II.L ./
__ tJ~
~--, ..
,. _ .(,D
f'clJr
~
,
!
.1 • _.94 -
_.~5 . /0
URBAN AREAS OVERLAND TIME
OF FLOW CURVES
~ _ AOOt:'t.lnIY -' I
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p. 26"1.,
10. AREA Cfl C" .. E~R CP£~INv l>t G~.\it
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A!:TY 2 e£FC-Rt CSTA:NIN(; <1,.
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"0 I ",,-!
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'\ I I I I , I I ..
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C,S~H.l,C~::it ~p. F:;...-r CF un.:r:'1£ P!.Z!:M(i!~
HYORAUL!C CAFACITY OF GRATE
INLET IN SUM?
.. -~. .
:'. .. . ... --__ 0.-.• _ ...... ,:-.. -'. =---' . , _. . . " --._ .. -----.... _. ."., ...
." ~ °0
L
/ INTENSITYpDURATION DESIGN CHA"" .... .... -.... - -....
-P.!iJ.;2I~-I..".f.. ...... qlI : ,II J'mrr.mn,l J 14'"'' j .. t II illiI .... '"lIiilr-:. • .', 'j :I.h ... l U.i:H Hluhn I
,._, ',I Equation: I = 7.44 P 6 D -.645
I" •
I·
• '0 .. .". . 30
I = Intensity (In./Hr.)
P' = 6
40 50 1
6 Hr. Precipitation (In.)
Duration (Min.)
2 3 4 5
'J" •• ""',.
6
0'\
I :c o c
"'1
Directions for Application:
1) From precipitation maps determine 6 hr. and 24 hr. amounts for the selected frequency.
These maps are printed in the County Hydrology
Manual (10, 50 and 100 yr. maps included in the
Design and Procedure ~anual).
2) Adjust 6 hr. "precipi"1:ation (if necessary) so
tha tit is \'/i thi n the range of 45% to 65% of
the 24 hr. precipitation. (Not npplicable
to Desert)
3) Plot 6 hr. precipitation on the rigr.t 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:
0) Selected Frequency yr.
. * 1) P 6 =; in., P 24= , P 6 = ~*
P24
2) Adjusted, *p 6= 1'n.
3)' t -min c -.
4) I = ___ inlhr.
*Not Applicable to Desert Region
Rev-ised 1/85 I\P.PFNOTX 'iT-1\
.......
... ,
---: ....
l. .crl til SAl DIEGO ouMTllEld' OF SANITATION I-
FtOOO CDHI'IlOL
"5' •
30'
IS'
'~""~", --lOO-YEAR L4-I-IOl~ PRECIPITlTimt -
r20"-/ISOPlUviALS o't 1 00 -YEAR 24-HOUR
}3· • "1 ~ ,1
,-1-
Its'
PN .. t··1IJ
U.S. DEPARTMENIr OF CQMMERCE
.A'IIOICAL ocpmc _0 AT:.Io5rllCltlC ADMIK •• .,aA nON ~ ftWICS altA:lfCII. o,raCK or "1Dlto&.OGY. HATlo;oiAI. .KAT .. " SClCYlC&
, 30' -l ... ....
~ •
lU'-1.5' )0'
.
''I' 117-laS' 10'
IIIiI __
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,;.'!.;1
-, , , . . ,,:~. '
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.... .,
~
• 4
.. -..
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1-'':,:
I ~~.~~~~~""I"" •• ~ •• ~ •. ~"I~"I"~I . ITt ", SAIl DIEGO
ir_ .. AlTIEII1 OF SANITATION I-
fl.0GD COlll1tOL
"S' \ I!IV'~ 1 N~~i»l\. • '" -.. J
I
30' I 1 VU 'I. \ J~'
,
• IS' ~ I ~;'L\,I ,.VI ~¥~ I V.~_1 . ··~~Eb~ ~"
33·
'''s' I II' ~' [. r .... "-~JI .. V ... " ~ '-., ~J\ '1'.\ 1 1'-l9 . __ , _A.h.'I-ii :;A~ ~-~ 1:
p,.,. ~." . .. _ ..... - -.. ~ ..
u.s. DEPARn1£H r OF COMMERCE
IIA'IIOOtAt.oeIAIIIC AltD AT IPlI& .. e ADlm'tISTIIA'I10H .~.., ..... aaMlat. ornca or II 'PItOLOGY. IIATIOHAL .IEATH'a. SltJtYlCE
118' 4S'
30' I I I II·" ~T -----~ f , , I ., I 1 f--'. •• .' ... t I.S· 30' IS' IU 30' lS' 117-
-a
, .
I"" "-P'I
TABLE 2
RUNOFF COEFFICIENTS (RATIONAL METHOD)
.. . .
, :', " 'DEVELOPED AREAS (URBAN) CoeffIcient. C
"
---Soil Group, (1)
Land Use
~e5 i dent i a 1 :
8 C ~ - -
:-., . S i "91 e F am i, 1 y .40 .-45 ;50 .55 "
"
Multi-Units .45 .50 .60 .,70
Mobite homes .45 .50 .55, '.65
Rural (lots greater than 1/2 acre) .30 e -.
.3S .45
Commercial (2) .70 .75 .80 .SS
80% Impervj ous
Industrial (2) .80 .85 .90 '.95
9ac~ lmpervj ous
'~OTES : .0 ~.
(l)Soil Group ~a~s are available at the offices of the Department of Public Wor}
(2)Where actual conditions deviate signJfi.can~IY from the tabulated impervious-
ness values of S004 or 90%. the values given for coefficient C. may be revls.
by mul ti'plyt n9 SO% or 90% by the rad 0 of actual imperviousness to the .
tabulated 'imperviousness. However, In no case shall the final coefficient
be less than ~.50. For example: ConSider commercial property on D'sotl.IT
:. ...... . . .. .. , .. , .
Actual tmpervious~e5s. • SO%
Tabulated imperviousness • SO%
Revised C • i2 x 0.S5·· 0.53 80 ...
... I . .-" "
. -. .
, !
I
j
j
j
J
J
j
j
I · , .. . .., . '.J ........ •
I. 1 Average Values of Roughness.Coefficient (Mannina's n)
I.' Rouahness Tn' of Waterway' Co.'f·lele'" en)
"'::"
1.
I· '. .
I '.
I · .... :
" ....
I: : 2~
''\.' . . .' , '"
.' ) .'. , .. -
I'· ..
(
3.
Close~ Conduits (1)
Steel (not lined)
Cast Iron
Aluminum
Corrugated Metal
Corrugated Metal
Corrugated r-tetal
Corrugated Metal
Concrete RCP
Clay (sewe;-)
(not lined)
(2) (smooth asphalt quarterlining)
(2) (smooth asphalt half lining)
(smo~th asphalt full lining)
Asbestos Cement"f/: PV<-
Dr~in Tile (terra cotta)
Cast-1n-place Pipe
Reinforced Concrete Box
Open Channels (1)
a • Unlined
Clay'Loam
Sand
b. Revetted
Gravel : Rock
Pipe' and Wire ~ . '.
Sacked Concrete
c. Lined I Co~crete (poured)
Air\ Blown Mortar (3)
Asphaltic Concrete or Bituminous Plant Mix' -:
d. Veg~tated (5)
Grass lined; maintained
Gra~s and Weeds
Grass lined.with concrete low. flow channel
Pavement and Gutters (1) • J
Concrete .
" .';': . 81 tuminous
•••••.. 'VW'."., ...... !~ " , .• :~... •
(plant-mixed) .
~':-... ~ .... ' :
". .. 0' : ... ~ .. ; ..
I
: ...... : . . ,
~t· ".: ...... ·~:·":'t~ .. : .:." .. ~
" .
.' ... .' . .' .
! " . . . , . .... ' , . ..
' .
0.015
0'.015·
.021
0:024 '.
0.021
0 .. 018
,0.012
0.012
0.013
... -0.011
0.015
O.OlS
0.014 .
0.023'
0.020
0.030
'0.040
0.02S
0.025
0:tfi4
0.016
0.018
• .03S
.045
.032
O.Ol.S .
0.016
"
. . ....
.. ' ..
I
I"
I
I
I
I
I
I
I
1-,\
\ t I ..
I
I
I
I
I
I
) I-:~.. .
~~: .. f·i~~I· •• • '. ,
.. .
• l ,
ErIe .. F. 8'lt.r Ind, HorlCI WIIiJam. Kin,
HANDBOOK OF
I
'.
. .
Table 7-14. Values. of K' for Circular (,hnnnds in tht, }c'ormuIB I
-u I d. , .00 _1 __ .
.0
.1 .009(;7
" ' ... .J)4.06
.3 :0907
.4 .1561
.S .232
.6 .311
.7 .388
.8 .4at
.9 .494 .
1.0 .483
. '. . ...
K' Q = -d~~Sl~
1l.
D -depth of wat(\f· d a di:Ullc'wr of channel
. 01 .02
,
.00007' .00031
.0118
.0448
.09G6
.1033
.239
.319
;395
.458 .
.496
: • t
I •
It
.0142
.0492
.1027
.1705
.2017
.327
.402
• 463
.497
..
,
.03 .04 .05
..-
.00074' .00138· .00222
.0)(;7 .OIH5 .0225
.0537 .0585 .0034
.1089 .1 J 53 .1218
.1779 .185-1 .19!!!)
.255 .2G3 .271
.335 .343 .350.
.40t) .416 .422
.468 .473 .477
.498 .498 .498
.
:
I . .OG .07 .08 .09
-
.Q0328 .00455 .OOft04' .00775
.0257 .0291 .03:!7 .03GG
.0086 .0738 .07U3 .0849
.J284 .1352 .1420 .101no
.2005 .2082 .2160 .2238
.279 .. ~87 .295 .303
.358 .3ft" .373 .380
.429 .435 .4'41 .4-17
.481 .485 .488 ... 91
."9G··,~ .494 .489 .483
. ,
I
I·
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
I
APPENDIX D
(6. HYDROLOGY MAP)