HomeMy WebLinkAboutCT 03-01-01; LA COSTA RESORT & SPA MSTR PLAN; DRAINAGE REPORT; 2005-06-23Drainage Report
KSL LA COSTA RESORT & SPA
COSTA DEL MAR ENTRY
CITY OF CARLSBAD
SAN DIEGO COUNTY, CALIFORNIA
June 23, 2005
Revised March 30, 2006
Revised September 26, 2006
Prepared for:
KSL LA COSTA
2100 COSTA DEL MAR ROAD
CARLSBAD, CA 92009
JIM WAPLES
Prepared by:
RBF CONSULTING
5050 Avenida Encinas, suite 260
Carlsbad, CA 92008
• • • 760.476.9193
CONSULTING
Contact Person:
Timothy M. Thiele, R.C.E. 60283
RBF JN 55-100221.008
HYDROLOGY STUDY
TABLE OF CONTENTS
SECTION 1 - INTRODUCTION
1.1 General Introduction 1
SECTION 2 - PROJECT INFORMATION
2.1 Existing Conditions 1
2.2 Interim Conditions 1
SECTION 3 - ANALYSIS/CONCLUSION 2
3.1 Flows 2
3.2 Pipe Analysis 2
3.3 Diversion Structure 2
3.4 CDS Unit 3
3.5 SD L-IA 3
APPENDIX- CALCULATIONS 4
COSTA DEL MAR ENTRY
HYDROLOGY STUDY
HYDROLOGY STUDY
1 INTRODUCTION
The La Costa Resort & Spa has prepared a Master Plan for the resort. The plan includes
construction of new resort villas, commercial buildings, parking structures and parking
areas, and various interior and exterior surface improvements around the resort. As part
of the approval of the Master Plan, an overall drainage study was prepared to address the
impacts of the new construction, and recommendations to remediate downstream
impacts. This report is titled "Drainage Study for La Costa Resort and Spa-Master
Plan", (Rick Engineering, Nov. 2003).
A new drainage report associated with the Villas Phase 2, "Drainage Study for La Costa
Resort and Spa Phase 2, (Hunsaker, 2005), showed that flows had increased by
approximately 15 cfs due to changes in the development plan. This promoted a
reevaluation of the 2003 Master Drainage Study. Himsaker recently completed a new
overall drainage study. Drainage Study for La Costa Resort and Spa (Hunsaker 2006).
As part of the Master Plan improvements the main entrance to the resort at the
intersection of El Camino Real /Costa Del Mar (ECR/CDM) will receive a new
gatehouse and new entry monuments. Portions of the existing storm drain system will be
removed and replaced with new storm drains as recommended by the new overall
drainage study (Hunsaker 2006). This new system would tie into the storm drain
improvements associated with Villas Phase 2 ofthe Master Plan.
This report will address the impacts due to the increased flow for pipe segments as shown
on DWG's 422-6D and 422-6F, the design for the diversion structure as part of the
ultimate storm drain system, the sizing ofthe CDS unit, and ponding depth at SD L-l A.
2 PROJECT INFORMATION
2.1 Existing Conditions
Existing runoff from La Costa Resort & Spa site are conveyed to two different locations.
Most of the Resort runoff is conveyed to the intersection of El Camino Real and Costa
Del Mar Road via sfreets and pipes. The Costa Del Mar runoff is collected and
discharged through an existing, highly corroded, 30" CMP directly into San Marcos
Creek. The runoff from the developed portion of the resort to the north is collected into
an earthen swale that flows southerly, parallel to El Camino Real. These flows are
collected by an existing headwall structure, which discharges through an existing pubhc
36" CMP storm drain pipe, crossing under El Camino Real and discharging into
Batiquitos Lagoon.
Costa Del Mar Entry
Hydrology Study
HYDROLOGY STUDY
2.2 Proposed Conditions
With the increase in runoff due to the proposed development listed in the Master Plan, the
intersection of ECR/CDM will continue to receive a majority of the runoff from the
Resort. Flow will be split by a diversion structure and conveyed through the new storm
drain pipes in Costa Del Mar and rehabilitated pipes in El Camino Real to evenly
distribute the flows between the pipe systems for better efficiency.
3 ANALYSIS/CONCLUSION
3.1 Flov/s
Flows from the site to San Marcos Creek are increasing slightly from the Qs shown on
the approved plans. The total increase is 3.43 cfs. San Marcos Creek and its North
Tributary have been modeled using the U.S Army Corps of Engineers HEC-2 Water
Surface Profiles program (May 1991). This study was completed by the Rick
Engineering Company in 2002 and defines a flood profile for the project area.
3.2 Pipe Analysis
The increase in flows outlined in the new overall drainage report (Hunsaker 2006) made
it necessary to upsize certain pipe segments to insure that the HGL would be contained
within the system. Pipe segments 34-38 were upsized in order to carry the increased
flows associated with the new overall drainage study (Hunsaker 2006).
3.3 Diversion Structure
The basis of design for the storm drain diversion just north of the El Camino Real/Costa
del Mar intersection is to maximize the flows that can be carried by the existing pipes
crossing ECR. The flow to be directed west across ECR will be 39 cfs, with the
remaining 43.20 cfs directed to the storm drain under CDM during the 1 OO-year design
event. Design flow rates are taken from the new overall drainage study (Hunsaker 2006).
Summary of Results
The results from the analysis shows that by lowering the invert elevation of the storm
drain pipe outletting towards El Camino Real by a 0.10 feet, decreasing the orifice
diameter to 30" while keeping the invert of the 30" orifice equal to the invert ofthe 36"
RCP, and lowering the invert elevation of the storm drain pipe outletting towards Costa
Del Mar by 0.60 feet, it would provide the needed diversion distribution of flows during
the 1 OO-year design event and would have maximum headwater elevation in the clean-out
structure of approximately 14.98 ft, which is 1.82 ft below the rim elevation.
Costa Del Mar Entry
Hydrology Study
HYDROLOGY STUDY
3.4 CDS Unit
The basis for design will be based upon the Rational Method for sizing calculations:
Q = C*I*A where:
Q = design treatment flow rate in cubic feet per second (cfs)
C = runoff coefficient (no units)
I = rainfall intensity in inches per hour
A = tributary area in acres
Summary of Results
The results from the analysis showed that 4.81 cfs will need to be freated by the CDS
unit. Based upon the design requirements from CDS Technologies, the system would
require a Model No. PSWC 40-40.
3.5 SD L-l A Analysis
The basis for design is to determine the ponding depth above the proposed grate inlet,
so as to determine if water will pond above the adjacent bench area.
Summary of Results
The results from the analysis shows that the ponding depth will 0.61 feet above the grate
inlet, which is approximately 0.39 feet lower then the adjacent bench area.
Costa Del Mar Entry
Hydrology Study
HYDROLOGY STUDY
References
Hunsaker and Associates. September 15, 2006. Drainage Study for La Costa Resort and
Spa. W.O. 2503-1
Hunsaker and Associates. July 14, 2005. Grading Plans for La Costa Resort and Spa
Phase 2. Dwg. No. 422-6C
Rick Engineering. November 3, 2003. Drainage Study for La Costa Resort and Spa -
Master Plan (REC Job No. 14107-L)
Costa Del Mar Entry
Hydrology Study
HYDROLOGY STUDY
APPENDIX
Costa Del Mar Entry
Hydrology Study
SCALE HORIZ. T- 20' VERT, r- 4'
HYDROLOGY STUDY
RIP-RAP SIZING
CALCULATIONS
Costa Del Mar Entry
Hydrology Study
7U ot I'y/Q^
//// I .• //
30 or 3'.V I
E' min I
fiaupj
f n-_'wjH (ly(, )
T/?-? 1 - l/i Ch Sill
Ty;..? ? - Witl.ojt sill
1 *• li.icliii".> o:' Ri;»r,i;» ,
U • Tij".- D-.ir.ctLT
V * Eutto::! WivJc't of Concrete Cm.-.;
Riprap li^r ihall te se;:<riet; on ?lcn?
s-'.ECTic-i 0.=' siPJi? A':o riLir'
\>loci;y
ft/S;c.
Rid
Clii^ificJtio.T '
P.ipra-T
ThicertlS {T) K.
f i ltT«- Clo-^r; •
\>loci;y
ft/S;c.
Rid
Clii^ificJtio.T '
P.ipra-T
ThicertlS {T) K. Sec. 2C3~ iec, "
12-; r-:-ic
IS-IC
lC-20
1:3. 3 liciinj
So^ 2 Zj<;iin;
FfcinT
1/iTTc.T
- r/2 Icn
1 To"
2 Ten
.n
1.0
1. <
-2.0
2'iJ
2. <
^.3
S.4
3/16" c: _ -
1/4- 81
3/3-
-.1/2-
r/4- - S.ird
i" - Sjr.d
11/2- - Sini
2- - -Sari
filler Elan!-eC T^.ic••^.^es^ » 1 foa~ or T, w.hic.'icv^r is leii
Sill <2O-C-2C0O
CliSS concrete,
if iko-.in cn Plar.s.
^zc-z/or, A-A
Concrete Channs'!
3C.-i./'J
ELEVATION
- 2. p-
KDT£5:
t. Type of riprap
a. F.e;-jlar Quarry Stone.
• b. E.'oien Concrete if S.'-.own cn ."'icns.
c. CsSbles not acceptable.
2. Cradilicn and Placer.enC as specified.in
P.cgicnil Standards Corr:. Std. Spe:. Prcv.
Sec. 203-1.6 znd Sec. 30G-S,
V 3. Riprap is to ba placed over a filter
blanket vi-hich nay be granular catcrial
cr plastic filter cloth.
a. Granular naterial specs, in Table
above-
b. Plastic filter cloth specs.-In Ee^. Stds.
€3.-=:. Std. Spec. Prov. Sec. 20^-1.7- •
A. If desired riprap and filter blanket class is
not available', use larger class.
*• S:jndird Specifications for PobTic Vorfcs ^
Construction by So. CA Chap.-of AP/--^ '
SAN DIEGO REGIONAL STArJOAHD DRA\7},VG
RiP RAP Ef'iERGY DISSlPA iCR
Cy Aer.fov.'J^
— .
HYDROLOGY STUDY
DIVERSION STRUCTURE ANALYSIS
Costa Del Mar Entry
Hydrology Study
La Costa Resort and Spa
Costa Del Mar
Flow Distribution through Diversion Structure Assuming Inlet Control
RBF JN 55-100221
10/2/2006
Watersurface Elevation
12.50
12.60
12.70
12.80
12.90
13.00
13.10
13.20
13.30
13.40
13.50
13.60
13.70
13.80
13.90
14.00
14.10
14.20
14.30
14.40
14.50
14.60
14.70
14.80
14.90
14.98
15.00
15.10
15.20
15.30
15.40
15.50
Flow through 30" Diameter
Orifice into 36" RCP El. 11.00
Q=0.6*A'(2GH)'K).5
11.82
13.98
15.86
17.53
19.06
20.47
21.79
23.04
24.22
25.35
26.43
27.46
28.46
29.43
30.36
31.27
32.15
33.01
33.84
34.66
35.45
36.23
37.00
37.74
38.48
39.05
39.19
39.90
40.60
41.28
41.95
42.61
Flow through 30" Diameter
Orifice El. 10.40
Q=0.6*A*(2GH)'K).5
21.79
23.04
24.22
25.35
26.43
27.46
28.46
29.43
30.36
31.27
32.15
33.01
33.84
34.66
35.45
36.23
37.00
37.74
38.48
39.19
39.90
40.60
41.28
41.95
42.61
43.13
43.26
43.90
44.53
45.16
45.77
46.38
Total Outflow (cfs)
11.82
13.98
15.86
17.53
45.48
47.93
50.25
52.46
54.58
56.61
58.57
60.47
62.30
64.08
65.81
67.50
69.14
70.75
72.32
73.85
75.35
76.83
78.27
79.69
81.09
82.18
82.45
83.80
85.13
86.43
87.72
88.99
Comment
Matches Assumed Inflow
HYDROLOGY STUDY
CDS UNIT
Costa Del Mor Entry
Hydrology Study
CONS U LTI NG
PLANNINQ M DESIBN • CONSTRUCTmN
Baa.Ay^.SBOB • WWW.RBF.COM
,JOR 5S '100Z2.\. oo^
SHEETNO. \ I
CALCULATED BY DATE l°ll<&l0T
CHECKED BY DATE
SCAl F
S^TOEATF^tfii,,. OTP,
Page 1 of 1
l^foclel*
Designation
Treatment
Capaciiy Ranip
Screen
DiameteiWeight
Siflnp
Capacity
Depth Below
Pipe Irvert
Foot Pri rt
Diameter
l^foclel*
Designation cfs MGD m (yd') m (ft)
PMIU20_15 (Drophin fiUet) 0.7 0.5 2.0\1.5 0.5 4.2 4,8
PMSU20 15 4 0.7 D.5 2.0 M.S 0.5 3.5-4 4.8
PMSU20 15 0.7 0.5 20\1.5 1.1 5.1 60
i
2
PMSU20 20 1,1 OJ 2.0 \2.0 1.1 5.7 6.0 i
2 PMSU20 25 16 1 2.0\2,5 11 6.0 6.0
PMSU30 20 2 1.3 3.0 \2.0 2.1 6.2 7,2
PMSU30 30 3 19 3.0\3.0 2.1 7.2 7,2
Pfti5SU40_30 4,5 3 4.0\3.0 5.6 S.6 9.5
PIVISU40 40 0 3.9 4.0 \4.0 5.0 9.6 9,5
pswcao^ 20 2 13 3.0 \ 2.0 19 6.0 7,2
h PSW30_30 3 19 3.0 \ 3.0 IS 7.0 6.0
PSVVC30 30 3 19 3.0 \3.0 2.1 7.0 7.2
£
QL
PSVVC40 30 i 4.5 3 4.0 \3.0 19 g.5 8.3
—>>•
PSWC40 40
• n
6 3.9 4.0\4.0 19 9.6 8.3
PSW60_42 9 SJ ao\4,2 19 9.6 9,5
PSVVC56 40 9 5.8 5.6\4.0 19 9.6 9.5
s PSW50_50 11 7.1 5.0\5.0 19 10.3 9.5
PSW356_53 14 9 5.6\5.3 1.9 10.9 9.5
PSWC56_6S 19 12 5.6\6.S 19 12.6 9.5
pswcse 78 25 16 5.6\7.8 19 13.6 9^.6
PSW70 70 25 17 7.0\7.0 3,9 14 12.5
pmmo m m 19 10.0\6.0 6.9.0f14,1 12
PSW1O0L8O 50 32 10.0\8.0 6.9or14.1 14 18
PSW100 100 64 41 10.0 \ 10.0 6.9 or 14.1 16
= s CSW150 134 148 95.5 15.0 \ 13.4 14.1*** 19.6*** 25.5
to g CSVV20CL164 270 174 20.0 \ 16.4 14.1*** 22.6*** 34.5
Q a. CSW240 160 300 194 24.0 \ iao 14.1*** 212*** 41
*CDS Piecast Marihole Irsert Unit (PMRJ). Pfscast Mantote Stonmwater Unit (PMSy), PrecastStorimvaterConcer«c
Precast (P). and Gast In Pfece (C), Stormv^^tser (SW)
(PSWC).
XDS Technologies can cigtomize ui^ts to meetspecfflc design ftows and sump capacif es
*Sump Capacifies arKl Deptfi Below Pipe ln*«rtcan vary dte to specific ate design
http://www.cdstech.com/dnlds/docs/CDS%20Unit%20Capacities.jpg 10/18/2005
HYDROLOGY STUDY
SD L-IA
Costa Del Mar Entry
Hydrology Study
• • •
CONSULTING
PLANNING • DESIGN • CDNSTRUCTIQN
SaO.479.380B • WWW.RBr.COM
.inR
SHEETNO. OF '
CALCULATED BY DATE *°U€.\0S
CHECKED BY DATE
SCAl F
^3^100 ' 12.42 (L^ 9^')
2^'
31:
Vi s. 'eiJeo Tfcr D