HomeMy WebLinkAboutCT 00-19; Carlsbad Promenade; Tentative Map (CT) (2)CARLSBAD PROMENADE
PRELIMINARY DRAINAGE STUDY
SEPTEMBER 2001
O'DAY CONSULTANTS
JN 97-1039
This is a preliminary drainage study based on the tentative njap prepared in
September, 2001, a single family residential development. The project is located at the
northeast comer of Aviara Parkway and Poinsettia Lane.
This study uses the rational method as found in the County of San Diego Drainage
Manual.
Q = CIA where
C = 0.45 (undeveloped)
C= 0.55 (single-family residential)
For soil type D
I = 7.44(P6)(Tc)"^^ where
P6 = 2.7
P24 = 4.3
P6/P24 = 0.63
1-. - 507
W^r 28/
i-= SSS'
6) PT 2
^TC^ =.4lfS.l<.)r Z.MI
Q- °[.\ CP5
7 = I. 5^ ,n ^
(Sl PT. 3
Q~ l(j!.ZcFS
1 - Y
firv£-
T - /n (
T - lz.^o+/.-)/ -- /2.lt
^C/v=^ , n(6,S'?)+,85Co,C^) ^ SSI
Wr 2-93
L - = o.o4 /Vl'.
T= o.ioi
(2, IMU^^T 2.-7 s
11^
•^MlAi A
SBO'
X= I'^-S mi^.
T- O- 'X rvu.1^ .
To - i'^.?>i-o.i - (9-5
L- 2.0C? '
/\ = O. O «o
Q--3.0 c^<,
Q= CO-^^X^^.I ^w'^h.O Kc"^ 13.-5 cC
-BA^I/^ 3
SH7O
To =- iO. 7.A- rviin-
(fY\> IA
O. fPCf^ rv-v I
B /O.O OFS
TABLE 2
RUNOFF COEFFICIENTS (RATIONAL METHOD)
DEVELOPED AREAS (URBAN)
Land Use
Residential:
Si ngle Family
Multi-Units
Mobi1e homes
Rural (lots greater than 1/2 acre)
ComfDerci al (2)
80% Impervi ous
Industrial (2)
90% Impervious
Coefficient, C -
Soi 1 TypeC)
A B C 0
.'lO .^5 .50 .55
.^5 .50 .60 .70
.k5 .50 .55 .65
.30 .35 .ko .ks
.70 .75 .80 .85
.80 .85 .90 .95
NOTES:
(Oobtain soil type from Append i ces IX-Cl thru IX-C^t.
(2)whe re actual''condi tions deviate significantly from the tabulated impervious-
ness values of 80% or 90%, the values given for coefficient C, may be revised
by multiplying 80% or 90% by the ratio of actual imperviousness to the
tabulated imperviousness. However, in no case shall the final coefficient
be less than 0.50. For example: Consider commercial property on D soil.
Actual imperviousness = 50%
iousness = 80% Tabulated impervi
Rev ised C = 50 X 0.85 = 0.53
80
FIGURE 14.4-
III.199 APPENDIX IX-B
>go County California
Qjoins
COUNTY OF SAN DIEGO
DEPARTMENT OF SANITATION 5-
FLOOD CONTAOL
'l5
O
00
31
rn
33'
30'
15
'15'
lOO-YEAR 24-ll0ljf{ PRECIPITATIOM
'-20-^ISOr'LUUIflLS or 100 -YEAR 24-IIOUR
PHECIPITATIOM IM JEMTliS OF AN INCH
Pre (IU
U.S. DtPARTMtN
NATIONAL OCUAMC AND AT:
SPECIAL STUDIES UKANtll, OKI ICU OT 11
30' -
116- .
'^^PF.N^TX XT-II
COUIfTY OF SAN DIEGO
DEPARTMENT OF SAWITATION &
FLOOD CONTROL 100-YEAft 6-11001 PRECIPlTATIOiJ
-20-/ ISOPLUVIALS OF 100-YEAR 6-IIOUR
pnECIFiTATiOJl \l\ knillS Gr AM lilCll
tt5'
30*
O
Ul
3
c
m 15';.
(X) 33'
^i5'
P repn
U.S. DEPARTMEN
NATIONAL OCfANIC AND AT.'
SPECIAL STUDIES DKANCII, OFFICL OFM
30
ll b|r
r OF COMMERCE
OSI'IIEMIC ADMINISTRATION
DKOLOGY. NATIONAL WEATIIER SERVICE
118'
£xC7/77p/a
C/i^s/T .- L cr/rgM a/" £/ok^ • JOtO /"/
^ AO 'A. 7- =
SAN OIEGO couNrr
DEPARTMENT OF SPECIAL DISTRICT SERVICES
j DESIGiM MANUAL
! APPROVED •'- / • ' '.xr r^'
URBAN AREAS OVERLAND TIME
OF FLOW CURVES
OATE
I AP°E,MCIX X
RCSIOeMTlAL STREET
ONE SIDE ONLY
5 6 7 a 9 10
DISCHARGE (CFS)
1
20 30 40
1
50
EXAMPLE:
Given 1 Q.= 10 S = 2.5%
Chart gh»M: D«pth = a4, Velocity = 4.4 tfxs.
SAN DIEGO cou>rrY GUTTER ANO ROADWAY
DEPARTMENT OF SPECIAL OlSTRICT SERVICES DISCHARGE-VE LOC ITY CHART
DESIGN MANUAL .
APPENDIX X-D