HomeMy WebLinkAbout1086; Kalicki - Drainage Report; Kalicki - Drainage Report; 1996-12-10Conrad C. Hammann, Jr. PE
land planning civil engineering surveying
2718 Waterbury Way
Carlsbad, CA 92008
619-434-8822 FAX 619-434-4474
JDB NAME'
JDB NDi _
DATE. (_
BY.
nr 2.7
r
PRnJECT MAMF;
TRACT ND, :
CLIENT:
DRAINAGE
REPORT
CDNRAD C, HAMMANN R.C.E. 33069
CONRAD C. HAMMANN, JR. PE KALICKI
2718 WATERBURY WAY MS/TM
CARLSBAD, CA JN 1086
619-434-8822 PAGE"ZQF'-7 /
TABLE OF CONTENTS: PAGE
SUMMARY
METHODOLOGY ." ...»
HYDROLOGY '.
CHARTS
APPENDIX
C:\MPS1\1086.DRN
CONRAD C. HAMMANN, JR. PE KALICKI
2718 WATERBURY WAY MS/TM
CARLSBAD, CA JN 1086
619-434-8822 PAGEli_OF±l/
STUDY SUMMARY
BASED ON THE INFORMATION PROVIDED WITH THIS REPORT, NO ADDITIONAL
DRAINAGE STRUCTURES ARE REQUIRED. THE PROPOSED STREET IMPROVEMENTS
WILL CONVEY THE REQUIRED 100 YR. DESIGN STORM. THE NET INCREASE IN
RUN OFF FROM THE PRE-EXISTING CONDITIONS COMPARED TO THE POST
DEVELOPED CONDITIONS ARE NEGLIGIBLE. ANY DRAINAGE IMPACTS CAN BE
MITIGATED WITH THE NORMAL DRAINAGE IMPACT FEES.
C:\WPS1\1O86.DRN
CONKAD C. HAMMANN, JR. PE KALICKI
2718 WATERBURY WAY MS/TM
CARLSBAD, CA JN 1086
619-434-8822 PAGE^/ OF<• ?
METHODOLOGY
I. STUDY APPROACH
For our design criteria we used the County ot San Diego Department
of Public Works Flood Control Division Hydrology Manual, 1979 and
the Standard Design Criteria for Design of Public Works
Improvements in the City of Carlsbad, 1990.
In preparing this report it was assumed that:
the existing green houses are in adequate condition for the
purposes of developing a run off coeficient.
existing Linmar Lane will continue to drain into the existing
paved ditch along the northerly boundary of this subdivision.
Study purpose
The purpose of this study is for the tentative map and is
preliminary in nature. A final report will be required during the
final map process to confirm the assumptions made in this report.
II. HYDROLOGY DESIGN CRITERIA
A. The design criteria, as found in the County of San Diego
Department of Public Works Flood Control Division Hydrology
Manual, specifies the design runoff conditions within the San
Diego County Flood Control District (April 1979 Edition) will
be based on the 100 year storm frequency as follows:
1. Design for areas over 1 square mile will be based on the
100 year frequency storm.
2. For areas under 1 square mile.
a) The storm drain system shall be designed so that
the combination of storm drain system capacity and
overflow both inside and outside the right of way
will be able to carry the 100 year frequency storm
without damaging adjacent existing buildings or
potential building sites.
C:\WPS1\1O86.DRN
CONRAD C. HAMMANN, JR. PE KALICKI
2718 WATERBURY WAY MS/TM
CARLSBAD, CA JN 1086
619-434-8822 PAGE:> OF- /
b) The storm drain system ^shall be designed so that
the combination of storm drain system capacity and
allowable street overflow will be able to carry the
100 year frequency storm within the street right-
of-way.
c) Where a storm drain-is required under headings 1 or
2 above, then as a minimum, the storm drain shall
be designed to carry the 10 year frequency storm.
3. Sump areas are to be designed for a sump capacity or
outfall of a 100 year frequency storm.
B. The design flows were computed based on the following
assumptions and data:
1. All soil groups were assumed to be Group D-very High
Runoff Potential. There are some areas where a Group C
soil group could be used. We chose to use a more
conservative approach.
Soil groups were segregated into groups depending on
their infiltration capacity as follows:
GROUP A - LOW RUNOFF POTENTIAL:
Soils having high infiltration rates even when thoroughly
wetted, consisting chiefly of deep, well to excessively
drained sand and/or gravel. These soils have a high rate
of water transmission and would result in a low runoff
potential.
GROUP B - MODERATE RUNOFF POTENTIAL:
Soils having moderate infiltration rates when thoroughly
wetted, consisting chiefly of moderately deep to deep,
moderately well to well drained soils with moderately
fine to moderately coarse textures. These soils have a
moderate rate of water transmission.
GROUP C - HIGH RUNOFF POTENTIAL:
Soils having slow infiltration rates when thoroughly
wetted, consisting chiefly of (1) soils with a layer that
C:\WP51\1086.DRN XO
CONRAD C. HAMMANN, JR. PE KAL.ICKI
2718 WATERBURY WAY MS/TM
CARLSBAD, CA JN 1086
619-434-8822 PAGE/2_OFi-_7
impedes the downward movement-,o± water, or (2) soils with
moderately^fine to fine texture and a slow infiltration
rate. These soils have a slow rate of water
transmission.
GROUP D - VERY HIGH RUNOFF POTENTIAL:
Soils having very slow infiltration rates when thoroughly
wetted, consisting chiefly of (1) clay soils with a high
swelling potential; (2) soils with a high permanent water
table; (3) soils with clay pan or clay layer at or near
the surface; and (4) shallow soils over nearly impervious
materials. These soils have a very slow rate of water
transmission.
2. The following manning roughness and rational method
runoff coefficients were used:
Table 1
MANNING ROUGHNESS "n" VALUES
PIPES "n"
Corrugated Metal Pipe 0.024
Reinforced Concrete Pipe 0.012
Cast in Place Concrete Pipe 0.015
Asbestos Concrete Pipe 0.011
OPEN CHANNELS "n"
Revetment 0.040
Concrete lined 0.015
Natural grass 0.035
Reinforced Concrete Box Culverts O.O15
C:\HP51\1O86.DRN 11
CONRAD C. HAMMANN, JR. PE KALICKI
2718 WATERBURY WAY M3/TM
CARLSBAD, CA JN 1086
619-434-8822 PAGE7_OF\
Table 2 „
RATIONAL METHOD RUNOFF COEFFICIENTS
Land Use General Plan Designation
Coefficient C
Soil Group A B C D
RESIDENTIAL
Single Family Medium/Low-Medium density .40 .45 .50 .55
Multi Units High density .45 .50 .60 .70
Mobile Homes Medium-High density .45 .50 .55 .65
Rural Low density/open space .30 .35 .40 .45
COMMERCIAL Commercial,Non-residential
Reserve,Schools,Professional .70 .75 .80 .85
INDUSTRIAL Industrial,Governmental,
Public Utilities .80 .85 .90 .95
3. Rainfall intensities for the Rational Method hydrology
computations were taken from the County San Diego Department
of Public Works Flood Control Division Hydrology Manual,
Appendix XI.
4. Watershed boundaries and grades for proposed storm drains were
derived from 100 scale City of Carlsbad Topographic maps with
2 foot contours, prepared by Frasier Engineering, Inc. and
Cooper Enngineering, Inc. dated 1988.
III. DESIGN RUNOFF METHOD
The hydrologic analysis utilized in this report is the Rational
Method for watersheds less than 0.5 square miles.
C:\WP51\1086.DRM
CONRAD C. HAMMANN, JR. PE KALiCKI
2718 WATERBURY WAY MS/TM
CARLSBAD, CA JN 1086
619-434-8822 PAGE -f OF/ X'
The Rational Formula is Qp = CIA where:
>»
Qp = The peak discharge in cubic feet/sec.
C = Runoff Coefficient (Dimensionless)
I = Rainfall intensity (inches/hour)
A = Tributary drainage area (Acres)
If rainfall is applied at a uniform rate to an impervious
area, the runoff attributed to this area would eventually
reach a rate equal to the rate of precipitation. The time
required to reach this equilibrium is termed the time of
concentration.
For small impervious areas one may assume that if
precipitation persists at a uniform rate for at least as long
as the time of concentration the peak discharge will equal the
precipitation rate.
IV. DESIGN PROCEDURE
The following procedure was used in calculating quantity of
storm flow . Whenever the term "Manual" is used, it refers to
the "County of San Diego Department of Public works Flood
Control Division Hydrology Manual" dated April 1979. The
general procedure was developed by Los Angeles County Flood
Control District and has been modified herein for use in San
Diego County.
1. Determine the quantity of water for the initial area.
a) Estimate the initial time of concentration (Tc). For
natural watersheds this can be obtained from Appendix X-A
of the "Manual". Effective slope of natural watersheds
may be estimated from Appendix X-B of the "Manual". For
urban areas overland time of flow can be obtained from
Appendix X-C of the "Manual" or Caltrans Highway Design
Manual Figure 816.6A. Engineering judgement should be
used for the validity of the computed initial times. A
minimum of 5 minutes should be used for all basins.
b) Determine the type of soil from "Hydrologic soil Groups -
C:\WP51\1O86.DRN 13
CONRAD C. HAMMANN, JR. PE KALICKI
2718 WATERBURY WAY MS/TM
CARLSBAD, CA JN 1086
619-434-8822
Runoff Potential" maps of the County Soils interpretation
study. ^ .
c) Determine the area (A) in acres and the ultimate land use
from the local agency Zoning Map.
d) Obtain the runoff coefficient "C" from Table 2.
e) Obtain the intensity (I) from Appendix XI "Intensity-
Duration Design Chart" of the "Manual".
f) Calculate the quantity of water (Q) from the "Rational
Equation", Q=CIA.
2. Determine the quantity of water for subsequent subareas as
follows:
a) Determine the water route from the point of concentration
of the previous subarea to the point of concentration of
the subarea in question.
b) Calculate the time necessary for the quantity of water
arriving at this subarea to pass through to its point of
concentration by the above route. The physical
properties of this route must be considered and the
velocities obtained from the following:
1) If traveling in a street the velocity can be
figured from Appendix X-D, "Gutter and Roadway
Discharge - Velocity Chart" of the "Manual" or
Caltrans Highway Design Manual Figure 816.6A.
2) If traveling in a ditch, pipe or other regular
section calculate the velocity from the actual
section.
3) If traveling in a natural watercourse the velocity
can be derived from the approximation of the
channel cross section.
c) Measure the length of flow to the point of inflow of the
next subarea downstream. From the velocity compute the
time of flow and add this time to the time for the first
area to determine a new time of concentration.
When determining the time of concentration (Tc), the
C:\WP51\1O86.DRN 14
CONRAD C. HAMMANN, JR. PE KALICKI
2718 WATERBURY WAY MS/'i'M
CARLSBAD, CA JN 1086
619-434-8822 PAGE/f: OF<V
expected future drainage facility and route is used to
determine ^velocity and travel time (Tt) . wherever
junction occurs, or there is a change in slope or
drainage facility, it is necessary to calculate the
velocity and travel time for the preceding reach. The
slope of the.Hydraulic grade line is generally assumed to
be parallel to the grade-slope.
d) Calculate Q for the second subarea, using the new time of
concentration and continue downstream in similar fashion
until a junction with a lateral drain is reached.
e) Start at the upper end of the lateral and carry its g
down to the junction with the main line.
3. Compute the peak Q at each junction. Let ya, Ta/ la,
corresponding to the tributary area with the longer time of
concentration. Let Qb, Tb, ib, correspond to the tributary
area with the shorter time of concentration and Qp, Tpcorrespond to the peak Q and time of concentration when the
peak flow occurs.
The usual case is where the tributary area with the longer
time of concentration has the larger Q. In this case, the
smaller Q is corrected by adding the areas multiplied by the
runoff coefficients of all contributing basins and then
applying the greatest time of concentration to obtain the
intensity for determining the peak Q. The tabling is then
continued downstream using the longer time of concentration.
C:\WP51\1O86.DRN
CONRAD C. HAMMANN, JR. PE KALlCKi
2718 WATERBURY WAY MS/TM
CARLSBAD, CA JN 1086
619-434-8822
HYDROLOGY
C:\HP51\1O86.DRH
STORM SEWER DESIGN
L & 0 229
ROU.C —
COUNTY.
. PRO J.
DISTRICT.
V/WIVII UIMIIUIVO ^«_^x**i»ti • •**••
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INVERT
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SMFFT OP
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(16)
FLOW
TIME
SEC.
(17)
REMARKS
(18)
STORM SEWER DESIGN
L & 0 229
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PRO J.
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(11)
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TIME
SEC.
(17)
j
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^^
REMARKS
(18)
rxcr
1
PROTECT
CALC.EATE
STATION
AREA
AREA REFERENCE
.057 (50 scale)
X .910 (200 scale)
91.8 (2000)
ACRES
.SHT_
CHKD
/. 3 / -S
OF
EATE
OEFFTCIENT OF RUNOFF: C (consider probable development)
Developed Areas (Urban)
% Land Use
Residential:
Single Family
Multi-Units
Mobile Homes
Rural (lots greater than 1/2 acre)
Commercial (2)
80% Impervious
/<£> Industrial (2)
90% Impervious
1ME OF CONCENTRATION C'
(Chart B-l)
Hl.Pt. "713 H.
Lo.Pt.7
RUNOFF: Q » I x CA
Altitude Factor =
\£> =« x 2
L.
C = ^min hr
(10 mln. minimum)
(Chart C)
I (actor
100
/hr
"/hr CA
Coefficient " C "
Soil Type ( 1)
A.
.40
.45
.45
.30
.70
B
.45
.50
.50
.35
.75
C
.50
.60
.55
.40
.80
D
(jTsJl *4'G>
.70 -
.65 «
.45 »
.85 -
.80 .85 .90
Tc /JI.9(L3
CA
Tc» Time In Hours
L= Distance In Miles
H» Height in Feet
C -
TO
/. 3 (/./ - c l)L'/l-
USE Q£<p
USE
CFS
CFS
Reference: San Du«go County Flood Control Design and Procedure Manual
(1) Obtain soil type from Appendices IX-C 1 thru IX-C4
PROTECT kAt. ICX/
WO# /00& SHT OF
CALC DATE CHKD DATE
X-5v
STATION <?£//+/&& A& *s AREA REFERENCE ^*S
g,. .057 (50 scale)
AREA £><O X .910 (200 scale) =
91.8 (2000)
/OO
OEFFICIENT OF RUNOFF: C (consider probable
Developed Areas (Urban)
% Land Use
Residential:
Single Family
Multi-Units
Mobile Homes
• Rural (lots greater than 1/2 acre)
Commercial (2)
80% Impervious
/OO Industrial (2)
90% Impervious
1ME OF CONCENTRATION^'
(Chart B-l)
Hi.Pt. d ~7 H. 2-Z. ' . _
. 05 ^ .
Lo.Pt. -^O L. <Y<Z>O
&. /& ACRES
development)
Coefficient " C "
Soli Typo ( 1 )
A B C D
.40 .45 .50 .55 =
.45 .50 .60 .70-
.45 .50 .55 .65 -
.30 .35 .40 .45-
.70 .75 .80 .85-
.fln .85 .90 r.9^/^5^
C - •15'
CA-^/-7
TC= /ii.ga3^385
\ H /
Tc« Time in Hours
L* Distance in Miles
H» Height In Feet
RUNOFF:I x CA
Altitude Factor
* x
factor
C = _ min _ ^hr
(10 min. minimum)
(Chart C)
OO
"/hr /^> ' cfs
xO./7' -
"/hr CA 'Y./// cfs
USE 0^0'
USE
' O
/•
_CFS
CFS
Reference: San Diego County Flood Control Design and Procedure Manual
(1) Obtain soil type from Appendices IX-C 1 thru IX-C4
/<
PROJECT
WO#__
CALC EATE
.SHT
CHKD
OF
DATE
STATION
AREA
AREA REFERENCE
.057 (50 scale)
X .918 (200 scale)
91.8 (2000)
ACRES
QEFFICIENT OF RUNOFF: C (consider probable development)
Developed Areas (Urban)
% Land Use
Residential:
Single Family
Multi-Units
Mobile Homes
7 £-• Rural (lota greater than 1/2 acre)
Commercial (2)
80% Impervious
Industrial (2)
90% Impervious
1ME OF CONCENTRATION C'
(Chart B-l)
Hl.Pt. 5~0 H."7 ^0/27
L.
1C = min hr
(10 mln. minimum)
RUNOFF: Q » I x CA
Altitude Factor =/.o (Chart C)
I 2-2- "/hr
(actor
Coefficient " C "
Tc /ii.9a3
Tc» Time in Hours
L= Distance in Miles
H» Height in Feet
1100 CA cfs
USE
USE QIOO-
A
.40
.45
.45
.30
.70
.80
Soil
B
.45
.50
.50
.35
.75
.85
Type ( 1 )
C
.50
.60
.55
.40
.80
.90
.55 -
.70 -
.65-
r^5>£>-32.
rjfjaav
.95 -
c -OJ&
Raferencu: San DUMJO County Flood Control Design and Procedure Manual
(1) Obtain soil type from Appendices IX-C 1 thru IX-C4
CA -2*6.0
CFS
STATION.
AREA
AREA REFERENCE
O.
PROJECT
WO#__
CALC
Oc-
EATE
.SHT
CHKD
OF
CATE
.057 (50 scale)
X .910 (200 scale)
91.8 (2000)
OEFFICIENT OP RUNOFF: C (consider probable development)
Developed Areas (Urban)
% Land Use
Residential:
/<?& Single Family
Multi-Units
Mobile Homes
Rural (lots greater than 1/2 acre)
ACRES
Coefficient " C
Commercial (2)
80% Impervious
Industrial (2)
90% Impervious
A
.40
.45
.45
.30
.70
.80
Soil
B
.45
.50
.50
.35
.75
.85
Type ( 1 )
C
.50
.60
.55
.40
.80
.90
«
.70 -
.65 -
.45 »
.85 -
.95 -
C » . £T5
CA »o»5~y
1ME OF CONCENTRATION C'
(Chart B-l)
Hl.Pt.
TC
Tc* Time In Hours
L* Distance in Miles
H* Height In Feet
C = x min ^hr
(10 mln. minimum)
V
RUNOFF: Q » I x CA
Altitude Factor =
I - x
factor
MOO- x
(Chart C)
"/hr
"/hr CA
cfs
cfs
USE O -
USE QiQrt-
CFS
CFS
Referunco: San DU;«jo County Flood Control Design and Procedure Manual
(1) Obtain soil type from Appendices IX-C 1 thru IX-C4
PROJECT
W0#_
CALC EATE
.SHT
CHKD
OF
EATE
STATION gavS/^g"
tAREA
AREA REFERENCE
.057 (50 scale)
X .910 (200 scale)
91.8 (2000)
ACRES
OEFFICIENT OF RUNOFF: C (consider probable development)
Developed Areas (Urban)
% Land Use
Residential:
Single Family
Multi-Units
Mobile Homes
Rural (lots greater than 1/2 acre)
Commercial (2)
80% Impervious
?/ Industrial (2)
90% Impervious
.1ME OF CONCENTRATION C'
(Chart B-l)
Hl.Pt. H.
Lo.Pt.L.
RUNOFF: Q - I x CA
Altitude Factor =
I^2> * * 2.
far.tnr
I
C = /£? mln ^hr
(10 mln. minimum)
(Chart C)
factor
100- x 2.,
"Air
"/hr
Coefficient " C "
Tc /11-9(L3
Tc» Time In Hours
L= Distance In Miles
H- Height In Feet
A.
.40
.45
.45
.30
.70
.80
Soil
B
.45
.50
.50
.35
.75
.85
Type ( 1 )
C
.50
.60
.55
.40
.80
.90
&*«-
.70 -
.65 »
.45 -
.85 -
.95- &.?£>
c .a &3 '
CA - I.5*/
CA */'&/ cfs
USE 0^-
USE QIOO*
CFS
CFS
Reference: San Diego County Flood Control Design and Procedure Manual
(1) Obtain soil type from Appendices IX-C 1 thru IX-C4
CONRAD C. IIAMMANN, JR. PE KALlCKl
2718 WATERBURY WAY MS/TM
CARLSBAD, CA -JN 1086
619-434-8822
CHARTS
C:\WP51\1086.DRN
INTENSITY-DURATION DESIGN CHART March 19R2
-f'TiTrlTrrm.Trf ~m i H i
j Equation: I 7.44 P/D -64S
o
Intensity (In./Hr.)
6 Hr. Precipitation (In.)
Duration (Min.)
Directions for Application:
1) From precipitation naps 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 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 applicable
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:
0) Selected Frequency
1) P, -^
vr.
2} Adjusted *Pfi=
3) t = min.
4) I = in/hr.
V
P24
in.
*Not Applicable to Desert Region
^5 6 APPF.NDIX XI
IV-A-14
810-10
May 2, 1088
HIGHWAY DESIGN MANUAL
Figure 816.6A
Overland Time of
Concentration Curves
1000
UJUJu.
LJJoz
co
Q
_J
UJ><DC
H
O
Z
DC
UJ
800
600
400
200
CO
UJ
H-
z5
z
JT
UJ
DC
U.
O
UJ
Q
Z
<-J
DC
UJ
1/2
[S(100)]1/3
Where:
C
L
S
TO
Runoff Coefficient
Overland Travel
Distance in feet
Slope in ft./ft.
Time in minutes
c
_m Oin
RESIDENTIAL STREET
ONE SIDE ONLY
1.. _:.J ..„..,...., _
' ! : I
0.4
4 50 7 (J 9 10
DISCHARGE (C.FS.)
30 40
*\
EXAMPLE:
Given i 0= 10 S= 2.5%
Chart glvci' Depth = 0.4, Velocity = 4.4 (pis.
-I
: ;• , SAN DIEGO COUNTY
DEPARTMENT OF SPECIAL DISTRICT SERVICES
DESIGN MANUAL
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DISCHARGE-VELOCITY pHART> ; 1
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COUNTY OF SAN DIEGO
DEPARTMENT OF SANITATION »
FLOOD CONTROL 50-YEAR 6-HOU
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PRECIPITATION
OF 50-YEAR 6-HOUR
U.S. DEPARTMEF T OF COMMERCE
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'118*
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COUNTY Of SAN OIEQO .
DEPARTMENT OF SANITATION »
FLOOD CONTROL 50-YEAR 24-HOUh PRECIPITATION
ISOPLUVIALS
PRECIPITATION IN 1
OF 50-YEAR 24-HOUR
ENTHS OF AN INCH
r OF COMMERCE
UHOLOOy. NATIONAL WIArHK* IIIIVlCS I
U.S. OEPARTMEN
NATIONAL OCIANIC AND ATS. rruoiit DRANCII. orrict or n
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COUNTY>OF SAN DIEGO
DEPARTMENT OF SANITATION
FLOOD CONTROL
33*
100-YEAR 6-KOU^ PRECIPITATION
^20-/ ISOPLUVIALS OF 100-YEAR 6-HOUR
PRECIPITATION III E?3TMS OF AM IIIC!!
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U.S. DEPARTMEN
NATIONAL'-OCEANIC AND AT!
SPECIAL STUDIES BRANCH, OFFICE OF II
30'J
JROLOCY. NATIONAL WEATHER SERVICE
118 \i
tCOUNTY} OF SAN DIEGO
DEPARTMENT OF SANITATION
FLOOD CONTROL
30'
15
33'
100-YEAR 24-HOl|R PRECIPITATION
^(UISOPLUVIALS OF 100 -YEAR 24-HOUR
PRECIPITATIOM IN ENTHS OF AN INCH
U.S. DEPARTMEN
NATIONAL octAsic AND AT
SPECIAL STUDIES BRANCH. OFFICE Qf 11
30'
OSPKC81C ADMINISTRATION
DKOLOGY, NATIONAL WEATHER SERVICE
Pf.p. '<t by
116-
CONRAD C. HAMMANN, JR. PE KALICKI
2718 WATERBURY WAY MS/TM
CARLSBAD, CA JN 1086
619-434-8822 PAGE_1.OF:
APPENDIX
C:\WP51\1O86.ORN