HomeMy WebLinkAboutCT 99-07; La Costa Fairway Villas; Tentative Map (CT) (20)HALE ENGINEERING
Civil Engineering - Surveying ~ Land Planning
73-10 Convoy Court San Diego, CA 92111
(619)715-1420 Fax (619) 715-1424
PRELIMINARY
HYDROLOGY STUDY
FOR
LA COSTA FAIRWAY VILLAS
Prepared by:
Hale Engineering
7840 Convoy Court
San Diego, CA92111
March 9, 1999
Job No. 9909
Purpose of Report:
This report is preliminary and should only be used to supplement the concept grading plan. The
purpose of this report is to show the changes in storm run-off due to site development. A 100-
year storm intensity of 3.5 in/hr has been assumed for all hydrologic calculations in this report.
Existing Condition;
Basin A: Area = 1.2 ac (see attached)
Runoff coefficient = 0.45 (undeveloped)
Ijoo =3.5 in/hr
Qioo= (0.45)(3.5)(1.2) = 1.9 cfs
Proposed Development:
Basin A: Area = 0.5 ac (see attached)
Runoff coefficient = 0.7 (multi units)
Iioo = 3.5 in/hr
Qioo = (0.7X3.0X0.5) - 1.2 cfs
Basin B: Area = 0.66 ac (see attached)
Runoff coefficient = 0.7 (multi units)
Iioo =3.5 in/hr
Qioo = (0.7X3.5X0.66) = 1.6 cfs
Q100 Total = 2.8 cfs
Job No. 9909 1 March 9, 1999
Conclusion:
In both existing and proposed cases, the storm run-off is discharged onto Gibraltar Street and
flows easterly to an existing curb inlet. The proposed development will increase the flow in
Gibraltar Street by 1 cfs. Since this increase is minimal, no modification to the existing storm
drain system will be necessary.
Job No. 9909 2 March 9, 1999
PRELIMINARY HYDROLOGY STUDY
EXISTING CONDITIONS
BASIN A
1.17ACRES
STREET
,.J •*.
"•••...
™m~~ '.'"
•-..
A4
rrrrrr
— -,
•-
"...
\x
-S-N-IN;;• '.'••
• '•'••
I i : \
\ -•
™~-—ZIZ,
•"•---—•- —
•.. ,?<¥%;r«^
- — -™~^ ?»—_._.
"^
^••-c) c)•• — / \_^< ...»<^js-- •••-. ..
"" ' — .---.--
--•
h
:::r
i-o ,
_
:E^ISTI.NG.::aR6 W::iDlTCH;u»~
!S>—
HALE ENGINEERING
CIVIL ENGINEERING SURVEYING LAND PLANNING
7840 CONVOY COURT
SAN DIEGO, CA 92111
(619) 715-1420
(619) 715-1424 FAX
40
iSS
40 80
SCALE 1" = 40'
PRELIMINARY HYDROLOGY STUDY
PROPOSED CONDITIONS
EXISTING BROW DITCH
HALE ENGINEERING
CIVIL ENGINEERING SURVEYING LAND PLANNING
?840 CONVOY COURT
SAN DIEGO, CA 92111
(619) 715-1420
(619) 715-1424 FAX
40 40
SCALE 1" = 40'
80