HomeMy WebLinkAboutDrainage Study Report (Nov.15,2001), ~
'
'
~
~
~
'
1
~
I ,
'
,
'
'
'
,
'
'
'
NOV 1 5 2U01
~1' OF TEMECULA
'CGU~.. ___
; --
~ s ~ ~
' + `~ . . `, ~
~ r,
~ _ . , .
.
. ~, `
~ --
~ .~ ~`1R
~ °~
DRAINAGE STUDY
REPORT
Tract 29928, 29928-1, 29928-2, and 29928-3: Harveston
City of Temecula, California
November 15, 2001
Prepared for:
Lennar
24800 Chrisanta Drive
Mission Viejo, California
Prepared by:
~ RBF CONSULTING
Contact Person:
Ejaz Mohammad, RCE 58580
27555 Ynez Road, Suite 400
~ ~ ~ Temecula, California 925 9 1-46 7 9
CONSULTING 909.676.8042telephone
909.676.72400 fax
RBF JN 15-100352.001
Revision History
Date Comments
8/23/01 Original
11/15/01 Modified per
comments City
of Temecula
~ " C58580 `" z ~~
~ ~rz 3~ n ~ ~
e *
J'J~ CNI~ ~~y~P n
'~ ~ ~~F ,ti,w~-~/
' '
1
~
~
'
,
~
~
~.
~
~
c
~
~
L
TABLE OF CONTENTS
STUDY SUMMARY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Background ....................................................1
1.2 Drainage Pattern ................................................1
1.3 Hydrology ......................................................1
1.4 Hydraulics .....................................................2
TABLE OF APPENDICES
Appendix A ........................................................... Figures
Appendix B .......................................................... Exhibits
Appendix C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hydrologic Calculations
Appendix D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hydraulic Calculations
Appendix E . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Storm Drain Improvement Pian
TABLE OF FIGURES
Figure 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Vicinity Map
Figure 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Tract Location Map
Figure 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Hydrologic Soils Group Map
TABLE OF EXHIBITS
Exhibit A . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Existing Condition
Exhibit6 ................................................... Proposed Condition
H:~otlataV 5f 003521CALCWytlrology1352rp00twptl
~ TRACT 29928, 29928-1, 29928-2, 29928-3 DESIGN REPORT ~
HARVESTON SPEC/FlC SITE PLAN i
2
'
'
' STUDY SUMMARY
~
1.1 Background
' The proposed tract (Tract 29928) is located in the County of Riverside within the corporate
boundary of the City of Temecula. The tract is part of master community development plan project
' known as Harveston. The project consists of about 520 acres of commercial, business park and
residential uses. The site is currently undeveloped and is bounded by Interstate 15 to the west,
the Winchester Highlands Business Park and Santa Gertrudis Creek to the South, Warm Springs
' Creek and the Warm Springs Specific Plan area to the north and east. Figure 1 indicates the site
vicinity and its relationship to the surrounding area. Figure 2 shows the tract boundary with respect
to the overall project boundary.
' Overall land gradients are moderate, averaging from about 1 to 5 percent in stream courses.
Ground cover is indigenous grass with fair coverage, and erosion does not appearto be a problem
in the streams or on the adjacent hilisides. Over 70 percent of the site is tributary to Santa
, Gertrudis Creek, either directly via Assessment District 161 (A.D. 161) improvements or by local
storm drain systems. The remaining portion ofthe site is tributaryto Warm Springs Creek. Runoff
from a majority of the site passes beneath Interstate 15 to local facilities in the Northstar Business
' Park and the Signai Landmark Business Park which ultimately discharge to either Santa Gertrudis
Creek or Warm Springs Creek. Smaller portions of the site are directly tributary to Santa Gertrudis
Creek and Warm Springs Creek.
' Purpose of this report is to summarize the hydrologic and hydraulic study resuits, and report the
designed pipe and inlet sizes.
' 1.2 Drainage Pattern
, Tracts 29928, 29928-2, and 29928-3, in the existing condition, are part of the drainage basin that
drain to 84" CIP culvert underneath Ynez Road. An infrastructure drainage pipe is proposed in the
Harveston Master Plan of Drainage ("Master Plan"), that will carry the drainage from these tracts
through closed pipes to the Ynez Rd culvert.
' Tract 29928-1, historically, has sheet flowed towards Margarita Road. Currently, after the mass
grading of the Harveston Elementary School, this flow is picked up by a catchbasin near Harveston
' School Drive, and is carried through pipe to the Margarita Road stormdrain system. In the
proposed condition, the flow from this tract will be picked up by inlets in streets KK and UU and will
join the Margarita Road stormdrain system
' 1.3 Hydrology
' The total drainage area is less than 300 acres, therefore Rational Method was used in estimating
the peak flow per Riverside County Flood Control Hydrology Manual.
, Discharges have been computed for 10-year and 100-year hypothetical storm return frequencies.
Rainfall used in the studies was taken from the Riverside County Hydrology Manuai for the 3
' TRACT 29928, 29928-1, 29928-2, 29928-3 DESIGN REPORT ~
HARVESTON SPECIFIC S1TE PLAN 1
,
t
1
'
'
'
'
'
1
,
'
'
'
'
STUDY
"Murrieta -Temecula and Rancho California" areas. Basic assumptions and criteria for use in runoff
computations are:
Hydrologic Soil Group B or BC;
Initial area is generally less than about 10 acres and flow path lengths less than 1,000 feet.
Figure 3 shows the hydrologic soifs group (HSG) over the project area. This figure shows that the
project site has a HSG of type B, except for 19 acres of the site which is HSG of type BC. Tract
29928-1 has HSG type B. Appropriate changes have been made in hydrologic models for tracts
29928, 29928-2, and 29928-3 to account for 19 acres of HSG type BC. The hydrology report for
these tracts are included in the Harveston Drainage Infrastructure Design Report. Exhibit-D of the
Drainage Infrastructure Design Report shows the proposed condition drainage basin boundary with
100-year peak flow.
The hydrology study for tract 29928-1 is performed in this study and is inciuded in Appendix C. The
total drainage area draining to Margarita Road storm drain system from this tract has increased
from 6.0 acres to 8.6 acres. Table A and B below summarizes the hydrology study resuit for this
tract. Exhibit-A and -B show the existing and proposed condition drainage basin boundary.
Table A: Tract 29928-1 Peak Flow Summary for the Existing Condition
10-year Frequency 100-year Frequency
Sub-basin
Name Drainage
Area (ac)
Tc (min)
Qpeak ~~s)
Tc (min)
Qpeak ~cfs)
210 8.6 18.0 5.8 18.0 9.6
Table B: Tract 29928-1 Peak Flow Summary for the Proposed Condition
10-year Frequency 100-year Frequency
Sub-basin
Name Drainage
Area (ac)
Tc (min)
~+ peak ~cfs)
Tc (min)
Qpeak ~~5~
210 3.10 14.9 4.4 14.9 6.7
220 5.5 15.7 7.5 15.7 11.6
' 1.4 Hydraulics
' Hydraulic calculations in the pipes were performed using Los Angeles County Flood Control's
Water Surface Pressure Gradient (WSPG) program. The downstream water surface elevations
for the pipes joining Infrastructure Storm Drain system (per Master Plan) were taken from the
' hydraulic calculation results of the Master Plan. These pipes include laterals C-1, C-2, E-1, E-2,
lines C, D, and E. The downstream water surface elevations for the pipes joining Margarita Rd
Stormdrain system were taken from stormdrain plan perA.D. 161.
'
' TRACT 29928, 29928-1, 29928-2, 29928-3 DESIGN REPORT ~
HARVESTON SPECIFIC SITE PLAN 2
-I
\\ " f
x
~' ~ M1`~ ~ CJ~`
, ~ _ ..5~ ~ , .
'
'
,
'
'
1
'
I '
'
; '
I;'
I ,
I '
I' '
I' '
'
Appendix D includes the hydraulic calculation results report. Inlets were designed for the 100-year
incoming flow. Appendix D also includes the inlet sizes summary and calculation report. Table C
~ below summarizes the pipe sizes designed in this study. Figure 2 shows the location of the
~ designed pipes. Table C below summarizes the designed storm drain pipe system. The storm
drain improvement plan is included with the study report that shows the pipe and the HGL profile
~of the designed pipes.
Table C: Designed Pipe Size Summary
'P.ipe~Nam~ Diameter pownstream System
Lat~A-1 ~ 18 in. Margarita Rd Stormdrain System
Lat A-~'1,i 18 in. Margarita Rd Stormdrain System
Lat. C-1 18 in. Ynez Rd infrastructure Stormdrain System
Lat. C-2 18 in. Ynez Rd Infrastructure Stormdrain System
Lat. E-1 18 in. Ynez Rd Infrastructure Stormdrain System
Lat. E-2 18 in. Ynez Rd Infrastructure Stormdrain System
Line C 18 and 24 in. Ynez Rd Infrastructure Stormdrain System
Line D 18 in. Ynez Rd Infrastructure Stormdrain System
Line E 18 and 24 in. Ynez Rd infrastructure Stormdrain System
' TRACT 29928, 29928-1, 29928-2, 29928-3 DESIGN REPORT ~
HARVESTON SPECIFIC SITE PLAN 3
~~
~ ~ ~ ~ ~
~
~
~ ~
DATE STflEET --
~ DATE STREET
'vd ~ i-_ T)
I m N % \~\ O~ N A ~~ ~ m V (0 /~ V m I O'~ N N I I~ N I- ~ 9
~ A Of
p V ~ V
__ ~ ~ A m ~n ~ ~
D ~" ~ - __ ~ STREET "00" ° .N ~~~- ~ S7"REET ~
F :~ N `',~ . ~ -10 in ~Q ~ m
m- 1 '° -1 N w m '
~ ~ _~ ~ ~ ~~ ~ w~ ~ w
m ~~ m N ~ m "~ N N m m a -~I -I-.._ v m o,' ° 'a m
A~ 10 ~ ~ ~ p ~ N ~ ~ w -I .__m _- ~.l S w. ~ __... _~ N .y _'.~ ~o N 'o
D ro r' C__-- y~ " - w w , ~ ,, o ~ N- ~
p o r Z 44 C 2 a j,,.. '~~ m m
S' ~ 2 ~ A ~
~~ ~ _~ ~ ~ ~ ro ~ ~ ~ ~ N~, ~ `~ ~ N ~ ~ I m •Wi
~ ~ ~ W a / ~~ ~ ~ A N -~'I ~'-. ~ /`~ ~ I
~ ~ -I \ 6+ ~ "' 33'. -L .J i o' W \` ~ ~\ C0 ~~ '~• w A
N N N ~ -- ~\ ' O ~ d ~ ~ W~~ W
` N ~ ~ A ~ j ag ' . IO ~/ ~ N ~
--) tlH '~ ~~~ ~ /` ~ \ Y
3s 3A1NQ NQls~n~ _ -_--:'°-i --~ --~-m.. .~'~~ 2 +~S be~ \ ~ w ~,
-r ~ ~=~_ ~~-1 N \` 5,. ~ w m I m
`~ ~If A /~ID ~\\ N 4)
N , W ~ ~N N A ,M ~
+,
`~ ~ ~ ~ ,, _ ~ _ . ~`~ ~ .
~
-I ~ _ ti~\ , i~ ~A ..
, rn A m m I \~`~ ~ A.~. < ~~ ~ m N~ tmt~ _.-~
~ 1 _ ~o ~ J .` ~ .
..;._~.Cv ~ N~ a 1 .a
~~Z ~ ! J / ro
~ A ~ ., _-~ ~ , ~~ 1
_ ~ ~ A ~ p I N N . . _. ~" m G~ / .. \ _, ~ \+! ~ ~ ~ "a
'~*1 YA ~ m y..- ~-1 ~ yS N~ ro~'ti a~ -~ m
~ i_, p m ~ 3ab ; o, y ,~ W
~~ , A , ~, m ~3 1 ~ N ~, /m v ~ m ; o ~
~ ~N-1 ~ '. N .' ~r ~~A _. ~' • \, N ~l N ~ / N . L N \ \ A
~~C ._.. 1 V ~. N~\tJ ~ ~/ ~ \
Z ~' `~ " ~' J ~ Pn N 1 m ~' N ' p ~.\ \ (I~N~ ~ ~'\
~. \
V , ~
m~a~ v o~ m ~ m ~ ~ ~ ~°y ~ °' ~
'~ ~~,;~ _ o~~_~ -
~ ~~ J
~ '
> p i j N .i q .~
~ / STREET CC ~v01~'t°n i _fO~- ~ F ~~ - m I~ o
D ~ ~ ~ , t~j O G N
Z _ _~......_ ~ N ~ . A A -: _ _ __"" n7 .
~ ' '. N~ ~ ~ ~ ( .~ ~~ +
m ! ~~--~- ~,n+~ ~ o -STREET "KK"-
.
A i _
O
~
?.~,1aj'..` A -. ..~.
d ` ~•N~A~. ~
N
~
z
I
1p _
._ ~
q p~
~ .
~ ~NN T6 \
. . N
/ ~ A
\ UI q p .. A ~ 1` ..
0\
•
1Ln
N
IA
m__ ~
pj~ \., ~~_
N\~•~
\m~
`y6 .. ~ ~ I A ~I 4f N
y
1~ V. ~ a'
~ m. m ""
'O~ f.~N
~ \ . '\fWll~.mv\ ~ \ y`~ ~
ayS
,,
N '.A
.'
~ ,. ,~
\~.
~:A ~ N
W RI
~ ---
~
" ~
`
~
,
~
W N
•
w\
~
~
' A
~
',
m ~ ~...
m
fo' y
~~
,
' °'
. ~
~, ~
P
'A z N .
C
.~ ~ ~.1.
....-
. V
\
W~,m \~ j~
. -C ~~
N ~
~
W
~
y ~ ~ n ~
~A
\~~
O ,~G D O '
-
~
~
N .\NNm~
~
~
~ O ,, i
1 O ep ~%
.'.
D
'~
~
v-I
~
.
~ An~A.oi~~ ~
~ ~'_
S
( (
\ ;
~.\N`H `.
~ '_.
.. ~
~-
a
~~
~.. __ _?!'_ ._\ 'l_.__
_..._ ~1 _- _ _ . -~
N
RVESr~,-~ ~ r-~._
. ,.
\
~
\
~
~
~ ~
9t
oe/an/oi u:m om
/~•~, ~ ~ ~ N HO -'^^
^y~r ' ~ N~ N ~~ ~I OC i
~~ ~ %~\~ p/ IO
N '..
P S m ~1
Ny~p ~^' ~~~ T RFFT
f,o ST \ ~ ~ .,kX„
/ L m"'~~ />
9Q N ~•' f'J ~ \~[ y N
\ °~ ,ay ~ "' ~ , m
\ N ` '>i_~ /
~ N~., y°' S> ~/ ~ o"~
m ~, ~ ~ ~~~~
/~ ; }.F'~ . m !Z~ ~ ~
i
w ~ m ~
o ~ ° ~ ~m
~
~ W ~ A`~ ~ ~j ~~ :
~~ ~ ~'" ~ ,
~c, ~'NCi~ " ~ j ~ ~ ~y
\
~%\ w~" Y ~ m
~~
f~ ~ t' ~~j`` ~ ~ i
~ ~ ~ ~ /%
\\\ W \ /~~ a//
~. q ~J ;.%/F /
~~~
o N
Z ~
N ~
(O T
c . N ~
G ,°' C
Z • ~ ~
~ m =
N D
~ G 1D
~ A
s - ~ --~ m
~ A
• N D ~
n
$~ ' R0 ~ Z
°
~
y
' N N
~ ~ t0 10
~ ~ ~
N N
~
~~~ W
~i ~ :
~ ~
~~ ~ ~
I'~;' `
~ ~, ..i
,,;,
i -- -
' II_~ -