HomeMy WebLinkAboutCDP 15-45; ABDI RESIDENCE; DRAINAGE STUDY ABDI RESIDENCE 5623 SHORE DR CARLSBAD CA 92008; 2017-10-13COFFEY ENGINEERING INC.
RECORD COPY
initial
Drainage Study
Abdi Residence
5623 Shore Drive, Carlsbad, CA 92008
APN 210-061-1300 \
Project Information:
I
Owner: Behrooz & Sharon Abdi
18485 Withey Road
Monte Sereno, CA 95030
o
CL
October 13,2017
ra
5
3
5
is
9666 BusinessparkAvenue, Suite 210 San Diego, CA 92131 Phone: (858)831-0111 Fax:(858)831-0179
Table of Contents
1. Existing Conditions 3
2. Proposed Project 3
3. Purpose and Scope of Report 3
4. Method of Calculations 3
5. Results and Conclusions: 4
6. Exemption from CWA Section 401/404 4
7. Declaration of Responsible Charge 5
Appendix A - Referenced Plans & Drainage Maps
• Drainage Map 'A' - Existing Drainage Conditions
• Drainage Map 'B' - Proposed Drainage Conditions
Appendix B - Calculations/Evalnations
• Table: 100 Year Storm Flow Rate Table
Appendix C - Reference Tables & Figures (County of San Diego Hydrology Manual)
• Soil Hydrology Groups
• Table 3-1 - Runoff Coefficients
1. Existing Conditions
The 10,940 sqfl (0.251-acre) site consists of a previously developed lot totaling 5,008 sqft of
impervious area and 2,131 sqft of pervious landscaping. The majority of the site (Basin X.l, X.2,
X.3) drains to the Pacific Ocean through two 4" drainage lines that outlet on the gunite bluff.
Basin Z, which consists of the impervious bluff surface located above the aforementioned drainage
discharge points, sheet flows to the ocean as well. Basin Y contains a small portion of the fiont
yard and driveway that sheet flows to Shore Drive. See Drainage Map 'A'.
2. Proposed Project
Proposed is the demolish of the existing residence and hardscape, and construction of a single-
family residence. Site improvements include retaining walls, hnpervious surface walkways, and a
sump pump. Proposed landscaping consists of the implementation of a biofiltration basin for
stormwater treatment. The site DMAs are divided into Basins A, B, and C, which rephcate the
existing flow patterns from Basin Y, X, and Z, respectively. Basin A contains the fi:ont yard and
driveway that will be imtreated due to its small area and slope towards the street Basin B consists
of the residence, paved walkways, and landscape areas that drain to the proposed 172 sqft
biofiltration basin for storm water treatment. Basin C is identical to pre-construction Basin Z in
area and flow pattem to the Ocean, and whl remain undisturbed.
3. Purpose and Scope of Report
This report will evaluate the existing and water run-off flow patterns and flow rate characteristics
for the project site. All calculations are for a 100-year expected storm event.
4. Method of Calculations
The Rational Method, as defined by County ofSan Diego Hydrology Manual (2003), will be used
to" calculate storm water flow rates. Where noted, the following calculations were used to
determine flow properties:
Pain fa 11 Characteristics
Q == C * I * A, where
Q = Flow rate (ft'/sec)
C = Runoff coefficient
(Runoff coefficient per County of San Diego Hydrology Manual Table 3-1 reproduced in
Appendix C. Soil type D determined from the Soil Hydrologic Groups map from the County of
San Diego Hydrology Manual reproduced in Appendix C also.)
I = Rainfall intensity (in/hr.)
A = Area (acres)
Rainfall Intensity (per Countv of San Diego Hvdrologv Manual Figure 3-1 reproduced in
Appendix C)
I = 7.44 * Pe * where
I = Rainfall intensity (in/hr.)
Pe = Adjusted 6-hour precipitation (inches)
D = Storm duration (min), equal to Tc for tune-of-concentration storms
Tc = Ti+Tt+Tp (time-of-concentration), where
Ti=Over land initial time.
Tt^Travel time on natural watersheds.
Tp=Travel time on drainage structures (pipes, brow ditch, gutter etc.)
Overland Time of Flow Iner County of San Diego Hydrology Manual Figure 3-3 reproduced hi
Appendix O
Ti= 1.8( 1.1 -C) /( s°'^^) (Overland initial time of concentration formula), where
D= Watercourse Distance (feet)(see table 3-2 for the max. overland flow length)
s = Slope (%)
C= Rimoff Coefficient
Ti=Initial time of concentration (min.)
5. Results and Conclusions:
In the existing conditions, a smaU portion at the front of the lot (Basin Y - 0.06 cfs) drains via
sheet flow over the top of the rolled curb along Shore drive. These flows join the pubhc flows
within Shore Drive and travel a short distance northerly to the pubhc storm drain system which
discharges at the base of the bluff and into the Pacific Ocean. The majority of the lot (Basin X
0.85 cfs) is picked up by an existing area dram system that discharges though the gunite cliff face
near the base of the bluff at two locations. The remainder of the lot consists of the impervious
surface cliff face (Basin Z - 0.37 cfs) that sheet flows to the Pacific Ocean.
The proposed project replaces the existing on-site area drainage system and utilizes the existing
discharge points at the base of the bluff. The proposed system includes the addition of a
biofiltration area, which receives runoff fix)m the majority of the site (Basin B — 0.91 cfs). A sump
pump is required to direct a small portion of hardscape runoff near the rear yard staircase to the
biofiltration basin. After the runoff is treated, flows are discharged to the two existing 4" PVC
drain lines that discharge to the Pacific Ocean at the bottom of the bluff. Flows in the front yard
portion of the property (Basin A - 0.06 cfs) continue to drain over the roUed curb into Shore Drive.
The gunite bluff (Basin C - 0.37 cfs) remains undisturbed, and discharges the same flows to the
Ocean.
In total, the pre-construction flows of 1.28 cfs in the 100-year storm will increase in post-
construction conditions to 1.34 cfs as a result of increased impervious areas on the site. Discharge
to the street wiU remain the same at 0.06 cfs. The total runoff to the Ocean will increase, from 1.22
cfs to 1.28 cfs.
6. Exemption from CWA Section 401/404:
The project is a single-family residence, and will not propose any structure below the high tide line.
Discharges will only consist of storm water; therefore 401/404 permits are not necessary.
7. Declaration of Responsible Charge
I hereby declare that I am the Civil Engineer of work for this project, that I have exercised
responsible charge over the design of the project as defined in section 6703 of the business and
professions code, and that the design is consistent with current design.
I understand that the check of project drawings and specifications by the County of San Diego is
confined to a review only and does not reheve me, as Engineer of Work, of my responsibilities for
project design.
[oU^ny
Michael Kinnear Date
RCE 76785
Exp. 12-31-18
1r3C76785
Appendix A -Reference Plans Drainage Maps
9GHT DtSTAiiCE CUARAMCE U«
EMSTtW UnUTY FULL BOX
(PROTECT W PLACE)
EXISTING RESIDENCEEMSTIMC cowa^ ore
(PROTECT W PWMI)
DOSTKG UTUJTY FULL BOX
(PROTECT N PLACE)DOSIKC StUER
(PROTECT W PLACE)
DaSTWG WAIL (PROTECT
W PLACE)EDOSnW AC PAVEMEHT
(PROTECT M PLACE)
EXISTH3 CONCRETE
DOSTIMG LAiiOSCAPNG
EJOSTDK WAIL (PROTECT
H PLACE)D9STKG 6' FTAC WATER
UAM PER PROXCT NO
W3-17. DWG MO 18-AD-3
(PROTECT t* PLACE)
DOSTIMC ROLLEDi CURB Art) GOITER
\ (PROTECT a Pl/CQ
E)QST»WvSEiER IWtKLE
LArtJSCAPE AREA PROPERTY DQSTING CONCRETE
EXTSTIMG SEVER UAM
(PROTECT W PLACE)(PROTECT PLACE)
Boa
LANDSCAPE AREA,LAKDSCAPE AREA
EJOSTING RRE HTORAKT
(PROTECT W PLACE)
DOSTftG WATER METER AND LATERAL
TO BE REMOVED AND REPLACED AS
fCCESSARY TO CCtfLY WTH CMC
STD DWG W-4 (1^* Uetor)
. grade
. -fifiEAA
F.F. = 40.101WALL PER
AflOfTECrS DETALS AS PAD = 39.27
PROPOSED EQUFICNT AREA
AND EHaOSURE WALLS TCR
<^7 ARCWTECrS DETAIL
LANDSCAft'
/UIWTS OF LOTER
WSTALL BACK FLOW DEWCE PER
CUWO DWt NO i-4 PROPOSED GAS fcETER
EXJSTJK LTTUTIES TO BE fCLOCATED
PROPOSED RESIDENCE
LOWER LEVEL FLOOR = 30.10
PAD = 29.27
SKHT DISTANCE CLEARANCE Ut€
PROPOSED NR CONDnWr® ^
UNTTS
EXETWG STREET LKHT WTITtfCONCRETE
PAD (PROTECT W PLACE)GAS LATERAL TO BE—'
Art) REPLACED.
PROPERTY LWE
S H E E N 0 .
DOSTIfl; BRCX WALL
(PROTECT M PLACE)
EXIST.
LANDSCAPE AftA SRADE BREAK
EXISTING CONCRETE DRTiEWAY
TO BE REUONED
RKHT-OF-WAY
PROPOSED WATER LDC
PROPOSED RESCENCE
FKSH FLOOR - 4ai0
EMSTFG ROLLED CURB
Art) GUTTER
(PROTECT W PLACE)
EXBTttG GARAGE
(PROTECT V PLACE)imgiES TO BE KSTAUED ra
Tbt REOUIREiefrS OF THE OTY
OF CARLSBAD FROU B-12 BURIAL
DEPTHS FDR YARD PPWG LArtSCAPE AREA
BCALEWFEET "AS BUILr
PROPOSED CONCSETE
DRTCTAYEXBTINC WDOOEN GAZEBO
(PROTECT H PLACE)LOWER LEVEL FLOCK - 3aK)SECTION G-G:
SCALE.
HORIZONTAL: 1* = 4"
VERTTCAL: 1* - 4*
EXISTTNO AC PAVOBTT
(PROTECT m PLACE)
PROPOSED SEWER LICDOSTWG FENCE
(PROTECT h PLACE)NOTE
DRAJN TO BE W-S.W-N-1) UWER
WOOD SW3WER UAH
REVEV^DBY
EXISTtNG BRCX PLASTER
(PROTECT h PLACE)
INQP£CT0R
A RK5HT-0F-WAY PERUU IS R£OUB?ED PRWR TO ANY
WORK WmiN THE PUBUC RIGHT-OF-WAY.IMPORTANT NOTICE
SECTION 4216 OF THE OOVERF«.<ENT
CODE REQUIRES THAT A WG AL£RT CENTIFICATION
NUMBER BE ISSUED BEFORE A
"PERMIT TO EXCAVATE" VWJ. BE VAUD.
FOR YOUR DIG ALERT I D. NUMBER CALL
UNDERGROUND SER\4CE ALERT AT
8-1-1
TWO WORKING DAYS BEFORE YOU DIG
B3 COFFEY ENGINEERING, INC.
4444 BU«NeUPAiU:AV0<UE.SUTTH 210. SAN NEOO.CAtZiai PH (1G»1S31-0111 PAX (960^1-0179
p;v\Y
ENGINEER OF WORK
John S Coffey, RE DATE
REGSTRATION NO. 62716 EXP: 6-30-16
SHEET
4-CITY OF CARLSBAD
BIGINEERUG DEPARTMENT
SHEETS
12
OEIDIKG PLAKS FOR
ABDI RESIDENCE
(3263 SHORE DRIVE)GR?017-001f) F^CJSE GRADING PLAN SHEET
APPROVED: JASON S GELDERT
CJTY ENGINEER RC£ 63912 EXPIRES 9/30/18 DATE
DATE wrriAL
REVISION DESCRIPTION
DATE WmAL DATE MTIAL OWN BY:
CHKD BY
RWiO BY
PROJECT NO.
CDP 15-45
DRAWING NO
501-8ADMMEER OF WORK OTHER APPROVAL OTY APP90VAL
DRAINAGE DETAIL:
SCALE: r « 3'
39.20 T.G,
39.70 T G
57.36 INV
37 30 37.07 [NV.
5714 INV
283
PROPOSED PUWP
STATION - SEE
DETAJL SHEET 8
24 x24 BROOKS BOX
57.65 RIM
33 90 IE
536 92
r-^
aT-oa-iNv I n
IMPORTANT NOTICE
PROPOSED SPA WTH STORH
DRAIN CONNECTION
DISCHARGE AND VALVES
PER SPA PLANS.
2" FORCE UNE
(SCHD. 40)
36.92 I E
39 10 T.G. Okd=0 46 CFS
34.80 INV. V>ii= 17.99 FPS
ENERGY DISSIPATION
RIP-RAP BASINS
RET WALL 4' PERFORATED PVC
SUBDRAIN - SEE DETAJL 1'. SHT. 9
EXISTING SETBACK
6" PERFORATED PVC SUBDRAIN
SEE DETAIL 'BIORLTRATION PtANTER',
SHT. 6
CURB WAa (TYP) PER DET^
'BIORLTRATiON PtANTER',
PR(iPOSED
fTT2 SF) -
37 65' PONE
36 90" BOTTDI
ORLTRATION/AREA
SEE DETAlu/ SHT
ING
M
EXISTWO RETAMHC WJJ.
(PROTECT IN PtX^)35 ^EMSTWC UW>SCAPWC
OaSTMG HMl
(ffiOTECTM RACE)
EMSnNe LAMTSGV^
Ft
7-6 3/r STEPS
EssTtte vna
(PROTECT IK RACE)
DEVtK
lAWSCAPMC
EXBTINC SETHAC*
EttSWG HAU
(PROTECT M
SCALE IN rar
PERMANENT TABLE
TYPE SIZE QWNfitSHiP
BIOFLTRATION 172 SOFT OWJER IN PERPEUNTY
SCALE IN
SECTION 4216 OF THE COVERtA<ENT
COOE REQUIRES THAT A DIG ALERT fDENTinCATKlN
NUMBER BE ISSUED BEFORE A
"PEROT TO EXCAVATE" WLL BE VAUO
FOR YOUR DtG ALERT LD. NUU8ER CAa
UNDERGROUND SERMCE ALERT AT
8-1-1
n TW WORWNC DAYS BEFORE YOU UO
ga COFFEY ENGINEERING, INC.
MM6u«NE»PAJD:AveiLie.tunE3io.tAND(ioacA92i3i m{e5S}ai-oin PAXfeSqOl-OlT?
P/VT)=
ENGINEER OF WORK
John S Coffey. PE DATE
REGISTRATTON NO 62716 EXP. 6-30-18
"AS BUILT'
RCE EXP—
REVEWODBY.
SPtET
5 CITY OF CARLSBAD
ENa]^EERlNQ DEPARTM9TT
SHEETS
12
OSADING PLANS FOE:
ABDI RESIDENCE
(5263 SHORE DW\E)
GR2017-0010 PRECISE GRADtW PLAN SHEET
APPROVED: JASCffJ S GELDERT
OTY ENGWEEK RCE 63912 EMTRES 9/30/18 DATE
DATE UmAL
A\
REVISION DESCRIPTION
DATE MTIAL DA*NTIAL
DIAN BY:
OfCD BT
RVW BT
fir PROJECT NO.
GDP 15-45
DRAWNO NO.
501-8AENOCER CF TPORK OTTO» tfPIWAL OTY APfWIVAL
DRAINAGE MANAGEMENT AREA (DMA) EXHIBIT
EXISTING CONDITIONS
0.013 AC.
0.111 AC.
UtUUUiUlLUUTTSSOT
0.052 AC.
cuuuiuuuu'U \ \ I \ \ T
0.011 AC
DMA ID
BASIN A
XX. XX AC
iiim- f -'1
0.063 AC.■an
EXISTING 4 PVC
STORM DRAIN
SCALE IN FEET
a COFFEY ENGINEERING, INC.
LEGEND:
-(36)-EXISTING CONTOUR
BASIN LIMITS
PERVIOUS AREA
(2,559 S.F.)
IMPERVIOUS AREA
(5,648 S.F.)
SITE CHARACTERISTICS:
HYDROLOGIC SOIL GROUP B
APPROXIMATE DffTR TO GROUND WATER > 20 FEET
CRITICAL COURSE SEDIMENT YIELD AREAS NONE
o
Q
X
LiJGT
CO
o
15-084
LOWER LEVEL FLOOR = 28.85
PAD = 27.94
PROPOSED RESIDENCE
LOWER LEVEL FLOOR = 30.10
PAD = 29.27
PROPOSED mNm¥t
yttLL PER DETAI.
ON 9CET NO 6
40 60 TW
35a3 TJ
PROPOSED SEVER SlAP FW
PER 0WLDf« FU»NS
DRAW TO ^'fSCESSED
UNDrajBODO SWiER UATT
DflSIMO FENCE
(PROTECT W PLACE)
DdSTWG BRCX PATIO
(PROTECT h FVUiE)
CCNTRACTOR TO LOCAt
ESTM STOn DRAM PPExIS^'brXKS CIEANOUT
35
NV 330 (2 PIPES OUT)
W FT.
EptTT
IE 330 jy^ROX. ±50 FT. FROU....-^DfSCHWGE
□OSTINC WOl
(FROTECT h PLACE)
IE 33 0 \
COMTRACTW TOFROPOS& SEKR LWES PERUEP PLArtS - SHEET P-2 2^DOSTUG FENCE(PROTECT IN PLACE)RETAJNED EDGE PERLANDSCAPE PK BEYCMJ CLEArtXIT
TO BEJ^WED
EMSWG 4^ PSC STDBNDRAM O S-60X (PER
DRAMA6E-STUDT)CONTRACTOR TO NEHPTLOCATION AS FffCESS«Y(PROTECT N PLACE)
SCALE IN
WYUGHT
EMSTWC FENCE(PROTECT N PLACE)
CONC. WALKlAiAY
EMSTINC RAISED WOO PA7K)(PROTECT h PLACE)WTERC
SD P
APPRO*
StemDOSIMG CDHCRETE WAiX
TO BE REyOSED
4" lEED SCREED (TtP)ffiOPOSED 4 PVC STOrai DRAM EMSTWC 4 PVC
DRAMSLUP PUUPPROPOSED GROUND LE«L4010 blDpp^di^ch»rces[BRECTLY MTD PACfflC OCEANY-S.OP*^ N GUNITEBLUFF DCCKARGES
PACrC OCEAN- XX FT/S0 wo - XX
"AS BUILT"LDCATKH AS NE(PROTECT M
EnSTMG GRACE
BACK CUT
PERkAyOfT SHORED WAJl
PER BUUMO PERUIT^PROPOSED LCmER LEVEL^FLOOR = 3010 DATE
REVBV53BY
DATE
CITY OF CARLSBAD IP^ga COFFEY ENGINEERING, INC.
V4M6UaHE»fARKAV0AlE.«j|TE2ia*AH[*OaCAf2131 PH (SSajBSI-0111 FAX {B«J«1-017T
PROPOSED RETAHNG WAALPER STRUCTLRAJ. ENCtCEFTSDCTAJIS SEE DEIAJ. R T4ON SHEET Na 12.
IMPORTANT NOTICE De>iARTMENT
SECTION 4216 OF THE GOVERNMENT
CODE REQUIRES THAT A DIG ALERT IDENTIFFCATION
NUMBER BE ISSUED BEFORE A
"PERMJT TO EXCAVATE" WLL BE VALD.
FOR YOUR WG ALERT I D. NUMBER CALL
UNDERGROUND SERVICE ALERT AT
OBADDTG PUNS FOR;
ABDI RESIDENCE
(5263 SHORE DRIVE)
Gfi2Q17-P01Q PREC3SE GRADW^G PUN SHEET
AVPPROVED:JASON S GELDERT
B-1-1
TWO WORKING DAYS BEFORE YOU DIG ENGINEER OF WORKhd. coezTie RCE 63912 EXPIRES 9/30/18CITY ENGMH?
bW By: _ffiCHKD BY:RWC BY:
PROJECT NO.
COP 15-45
DRAWNO NO
501-8AP/v\v>«DATE MllALJohn S Coffoy, Pf. DATE
REGISTRATION NO. 62716 EXP 6-30-18 REAS ON DESCRIPTIONENQntER CF 07VCR AffROVAL cm APPeOVAL
PROPOSED CONCRETE PAVM6PER LAiiJSCAPE AROfTECtS
DETAfl^
PROPOSED SUBORAiN PERSTRUCTURAL EKCHEER*SDETAILS SEE SHEET KG 9
PROPOSED SEVER PERPLUUBHC EMGMEER'S
PLAHS CM SHECT P-2 1
SECTION H-H:
SCALE
HORCONTAij r o 8*
VERTICAL- 1' - 8"
DRAINAGE MANAGEMENT AREA fDMAl EXHIBIT
PROPOSED CONDITIONS
-rwTi'
II
m
BASIN
m
SCALE IN FEET
EXISTING 4 PVC
STORM DRAIN
a COFFEY ENGINEERING, INC.
LEGEND
■(36)-
k "V 4' '4'
"V 4" 4"
EXISTING CONTOUR
BASIN LIMITS
EXISTING STORM
DRAIN TO REMAIN
PVC DRAIN UNE &
LANDSCAPE DRAINS
BROOKS BOX
W/GRATE
PUMP
PERVIOUS AREA
(1.811 S.F.)
IMPERVIOUS AREA
(6,396 S.F.)
BIOFILTRATION AREA
(172 S.F.)
SITE CHARACTERISTICS:
HYDROLOGIC SOIL GROUP B
APPROXIMATE DEPTH TO GROUND WATER > 20 FEET
CRITICAL COURSE SEDIMENT ^ELD AREAS NONE
DMA ID BASm AREA (AC.)DMA TYPE
BASIN A 0.013 SELF-MITIGATING
BASIN B 0.174 BIORLTRATON
BASIN C 0.063 N/A
o3E
Q
(NX
LdO
5:
CO
o
15-084
Appendix B -Calculation/Evaluations
100 Year Storm
Table B - Pre Construction Flow Conditions
Summary
Flow ID (Basin)
Runoff
Coefficient,
C
(5 min minimum)
Total tlme-of-
concentration,
(min)
Rainfall
Intensity, 1
(in/hr)
Basin
Area, A
(acres)Q(cfs)Flow ID (Basin)Flow Description
X.l 0.71 5.00 6.59 0.111 0.52 Y Drains to Ocean
X.2 0.80 5.00 6.59 0.053 0.28 X.2 Drains to Ocean
X.3 0.67 5.00 6.59 0.012 0.05 X.3 Drains to Ocean
Y 0.69 5.00 6.59 0.013 0.06 Y Sheet flow to Street
Z 0.90 5.00 6.59 0.063 0.37 Z Sheet flow to Ocean
Sum = 1.28
Table B - Post Construction Flow Conditions Table B - Hydraulics of Proposed Structures
Summary
Flow ID (Basin)
Runoff
Coefficient,
C
(5 min minimum)
Total time-of-
concentration, Tj.
(min)
Rainfall
Intensity, 1
(In/hr)
Basin
Area, A
(acres)Q(cfs)Flow ID (Basin)Flow Description
A 0.71 5.00 6.59 0.013 0.06 A Sheet flow to Street
B 0.79 5.00 6.59 0.175 0.91 B Discharges to Biofiltration
C 0.90 5.00 6.59 0.063 0.37 C Sheet flow to Ocean
Sum =1.34
DMA Tabulations
Basin
Permeable
Area
Impermeable
Area
Area (ft)Area
(Acres)'C Value Flow Pattem
X.l 1720 3132 4,852 0.111 0.71 Drains to Ocean
Runoff Coefficient
■c Permeable Impermeable
X.2 411 1876 2,287 0.053 0.80 Drains to Ocean 0.35 0.90
X.3 213 292 505 0.012 0.67 Drains to Ocean
Y 217 343 560 0.013 0.69 Sheet flow to Street
Z 0 2736 2,736 0.063 0.90 Sheet flow to Ocean
; Total 2a3if ' 5008 10,940 0.251 , " '
Basin Permeable
Area
Impermeable
Area Area (ft)Area
(Acres)'C Value Flow Pattem
A 196 365 561 0.013 0.71 Drains to Street
B 1552 6084 7,636 0.175 0.79 Discharges to Biofiltration
C 0 2743 2,743 0.063 0.90 Sheet flow to Ocean
Total 1748 ^ 9192 10,940 0.251
Capacity of Existing 4" PVC Outlet Pipe on Bluff (5) Approximately 60% Slope
DATE: 09-13-2017
TIME: 21:34:15
PIPE FLOW PHOGRAM
.010C2> Manninys n ...<1) Dxancter <inches>
1.92.6000<3> slopr; ..
1.00<f)> deiith/Dianetci*<5> depth «rft>0.33
7.48Uolocit.y HeadUeltjcity <fp5> .21.95
Ai-ea <S<(. l't.> .0.09
0.5952Ci'it leal SlopeCritical. Deptli .0.33
Froudu Nunber .(Iivi.tical Uelocity 21.95
Flow Characteristics of Existing 4" PVC Outlet Pipe on Bluff @ Approximately 60% Slope (Overall 'Q' of
0.91 from bioflltratlon basin is halved as flows feed Into two outlet pipes)
DATE: 09-13-2017
TIME: 21:40:57
PIPE FLOW PROGRAM
.010<2> Mannxiif(!i n< 1 > D .n.ane t e .r < xii c lie y >
0.46.6000 <4> 0 Ccfa>C3> s.lope ..
<6> deptii/D.i.anietei 0.330.11<5> depth <ft>
5.03Uelocxty Head ...Ueiocxty <fps> .7.99
Area <S<.(. Ft.> .
0.0301Givitical Slope ..0.33Crxtxcal Depth .
11.17Froude Nni:iher ... .Cr j.t xcit 1 Ue loc 11 y 5.25
Kf^Seuh
I
PROJECT LOCATION
tl
asjarirr
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!IQ AlA
County of San Diego
Hydrology Manual
Rainfall Isopluviab
25 Year Rainfall Event - 6 Honrs
Isopiuviai (Inches)
DPW
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OwiinvJKMm^jiSfrfkof
5aiiCilI>
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OR Onn, IHCLUDMO. BUT NOT LOrtED TO. THH aPUS} WARRANTEB
OF lElCHWABlJTY AND FIT>«88 FOR A P/»RT1CULAR PURP06E.
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fafbonaBoa eyvtMi «M:h cmt b« refvodooadMhoU Bm
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3 Miles
¥
unfy
PROJECT LOCATION
333ffl
Mart Iff
iM!'!iiaMRSII!S^:*iib3ifaE
1'.
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County of San Diogo
Hydrology Manual
Rainfall Isoplitvials
25 Year Radni^ Eysat - 24 Honrs
Isopluvial (Inches)
^g1 smcis
Wc Have San Dicgci CbvcretUD»pmtmncfPtMiVttt»
THM MM» B PROVma) WITHOUT WARRAMTY OF AW MW). BTHBl EXPRESS
OR U>US, MOJJDMQ, BUT LMTH) TO. TKi EPUED WARRANTIES
Of UHlCHWT>BflJTY AND HTNBS8 FO* A rvWTTCULAR PURPOee.
Copyright 8«dOQ. AJ RlgMi RAMTved.
T7^ pndoob nay oontih) hdonnalon tan tM 8A>ClAO R^jfanri
fnfriTMflnn IT>«fTi wHrh rnrnt ha i^rnilinil hBmjuI Iwi
Mtan pWTTtaian of 8ANM0.
TUi pmduct may conUa hofcmiAn vhUdi haa beeo npnxtaAd wlhpAnriMfan 7«ited byTtaoM BnJw l*p«.
3 Miles
DIracfkMii for ApptlcatkMi:
(1) From predpftatton maps determine 6 hr and 24 hr amounts
for the selected frequency. Those maps are Included In the
County Hydrology Manual (10.50, and 100 yr maps InctudodIn the Design and Procedure Manual)
(2) Adjust 6 hr precipitation (If necessary) so that It Is within
EQUATION
7.44 ^6
Intensity (In/hr)
the range of 45% to 65% of the 24 hr precipitation (not
appllcaple to Desert).
6-Hour Predpltatton (In)
Duration (mki)
(3) Plot 6 hr preclpltaUon on the right side of the chart
(4) Draw a line through ttie point parallel to the plotted lines.
(5) This line Is the Intensity-duration curve for the location
being analyzed
Applleatlon Form:
(a) Selected frequency Z.S year
(b)P6= g^ln..P24=5^.^= 51
^24(c) Adjusted Pg<2) = Z-f7(7(n.
(d) tv n 5 min.
(e) I a 5. Z.~1 In./tv
f4ote: This ctiart replaces the Intensity-Duration-Frequency
curves used since 1965.
lj«il3J>H4.49
g.M 110.60111.98
7.58 1 Sirl 9Z7
5.84 OB'TiTis
res > 5.39 ! 5.93
4.Z0 4.67 I ^13
3.73^1 4.f6_£4.56
3.10^! 3.45j"3.>9
2.M I 2.98 ' 3.28
2J»T 2.65 . Z921.84 j Z04~!'2.a'
1.53 I I'.TO" 1.87
i.32 I 1.47 I i'.B2
i.tej i.3i"! "i|^O.W I 1.081 1J9
6.85~I I
0.75 roT84it "a92
1.63 '
1J6 I
7 8 9 10 20 30
Minutes
Duration
fnt»n«lty-Our«tlon Dooign Chart - TempM*
FIGURE
mi •
CH£i(Nili:
PROJECT LOCATION
en:^i
ajt^ie
le-AiiA
IS
?K
:l:=
weaA^E
arse
County of San Diego
Hydrology Manual
Rainfall Isoplitviab
100 Year Rainfall Event - 6 Hours
Isopluvlal (inches)
^g1 s^gis
O^MrtJHor c/fttib WMb Wc Have San l^cgo C^ovcrcdi
■MS MAP 18 PIWVKIH) WimOLTT WAWWfTY OF AW KMD, HTHER EXPRBSSOft MtJEO, MCLUDINO, BUT NOT LJUTTH) TO. THE •«UG) WARRANTIESOF UBWiWWflUTY AND FnNBS FOR A PARTICULAR PURPOSE.Copyr^t SviQta Al RIahb ftKarved.
TW> pwdocb wy oooti*i Wor—Bon froa tha SANCWm RagfafniiDfcfTDdao Syvlwi «Mob cannol b« raproduo*d vJbaut ttwwtton ptmMoa of SANDAa
TMi product:t HW ccntiki Honnafiort hM bMo reproduced wttigrenid byThMDM Brotfaore Uip*.
3 Miles
Comity of San Diego
Hydrology Manual
Rainfall Isoplttvials
100 Year Rajniall Event - 24 Honrs
PROJECT LOCATION Isopluvial (inches)
e.
ca Mwl
DPW
5aiiGlS
wb Have San Diego Cijvcrcd!
T>te UM» B PROVtDfiD wrmoar WARRANTY OP AKT KIND, BTHER EXPRESe
OR WPUH>. WCLUDWG, BUT NOT LMTTED TO. THE EffUED WARRA>mB
DP USICHANT«IJTYAND FTTOEBS FOR A PARTICULAR PURPOSE.Con*^ SnGia Ai Ri^ RMwadMfatMb-EE'CI I
o£'
3 Miles
Olractiona for AppdcaUon;
(1) From predpttafion maps defenriine 6 hr and 24 hr amounts
for the selected frequency. These maps are included 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
appllcaple 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
Ireing analyzed.
AppllcMon Fonn:
EQUATJ0W
7.44 Pe D^ «45
Intensity (Infhr)
Pe = 6-Hoor Precipitation (In)
D " Duration (mite)
Ill !l
Durtfon
1.68 2.53
1.30 1.9S
ICS 1.S2
■"5 20 30 4b 50 i
Minutes
Ouration
24 %(2)
(a) Selected frequency (? year
(•') Pe ° 2 .gC7 in.. P24 = 4-.<7t7
(c) Adjusted Pg^^' = (p 3 in.
(d) t^ = ZSQ min.
(e) I = InThr.
Note: This chart replaces the Intenstty-DuraUon-Frequency
curves used since 1965.
ll.jtellllfll4.499.M I'lOCOi'lJJS_7;,M i 142 : 9J7s7b4T 6.49" TTia'IBS . 5.39";^^
: S.J33.73 I 4.15 i"4Ce>10 I 3.45 V3.79i"2.B9"i 2.98" i 3.28"' 2.39 i 2.66 • 2.92"; ,1.84 I 2,04
' J:?L' 1.70'ii32 : 1.47.1.1'e'! 1.31196 ' 1.08bies'i 0.94
; 2ZB' 1.07
1.82
i;44'
1.19"
1.03
6.46
5.60
"4.98"4.13
3.58""ai8ZjB
2.04"J.76"
1.571^"
i 1.13
1.00
fntenslty-Dunrtlofi Dealgn Chart - Templato figure
3-1
Appendix C -Reference Tables & Figures
(County of San Diego Hydrology Manual)
San Diego County Hydrology Manual
Date: Jmie2003
Section:
Page:
3
6 of 26
Table 3-1
RUNOFF COEFFICIENTS FOR URBAN AREAS
Land Use Runoff Coefficient "C"
Soil Type
NRCS Elements County Elements %IMPER A B C D
Undisturbed Natural Trarain (Natural)Permnnent Oprai Space 0*0.20 0.25 0.30 0.35
Low Density Residential (LDR)Residential, 1.0 DU/A or less 10 0.27 0.32 0.36 0.41
Low Density Residential (LDR)Residential, 2.0 DU/A or less 20 0.34 0.38 0.42 0.46
Low Density Residential (LDR)Residential, 2.9 DU/A or less 25 0.38 0.41 0.45 0.49
Medium Density Residential (MDR)Residential, 4.3 DU/A or less 30 0.41 0.45 0.48 0.52
Medium Density Residential (MDR)Residential, 13 DU/A or less 40 n 0.48 0.51 0.54 0.57
Medium Density Residential (MDR)Residential, 10.9 DU/A or less 45 0.52 0.54 0.57 0.60
Medium Density Residential (MDR)Residential, 14.5 DU/A or less 50 0.55 0.58 0.60 0.63
High Density Residential (HDR)Residential, 24.0 DU/A or less 65 0.66 0.67 0.69 0.71
High Density Residential (HDR)Residential, 43.0 DU/A or less 80 0.76 0.77 0.78 0.79
Commercial/Industrial (N. Com)Neighborhood Commacial 80 0.76 0.77 0.78 0.79
Commercial/Industrial (G. Com)General Commercial 85 0.80 0.80 0.81 0.82
Commercial/Industrial (OJP. Com)Office Professional/Commanial 90 0.83 0.84 0.84 0.85
Commercial/Industrial (Limited I.)Limited Industrial 90 0.83 0.84 0.84 0.85
Commercial/Industrial (General 1.)General Industrial 95 0.87 0.87 0.87 0.87
♦Hie values associated with 0% impervious may be used Bar direct calculation of the runoff coefBcient as described in Section 3.1^ (representing tide pervious runoff
coeflficient, Cp, for the soil type), or for areas that wiU remain undisturbed in perpetuity. Justification must be given fiiat the area wfil remain natural forever (e.g., tibe area
is located in Cleveland National Forest).
DU/A = dwelling units per acre
NRCS = National Resources Conservation Service
3-6
PROJECT LOCATION
3(nio
!QA!^
1
m
HquAME/
a>^j0
County of San Diego
Hydrology Manual
Rainfall Isopluvials
10 Year Rainfall Event - 6 Hours
Isopluvlal (inches)
DPW
of fttic toil
9ppvi0k Mnudw Sendbov Wc Have San l>icgD Oivcrcdi
TW UAP B PRCVm WTTHOUT WARRAKTY OP AW NIO. BTHB% EXPRSS
OR OHJm tCLUONQ, BlJr NOT LOITTH} TO, TTE UPUa} WARRANTE8
OP UBV^MnMLTTY AM) nnCBS FOR A fWHKUAR PURPOGE.
Cojyight SanOB. All Rfctfa Ru—ind.
THta FToduota ny ckxMi hrfonrvdon tva fM 8AM)AQ Ragbrai
tnfcoiMoa 8)vtm iMoh oamot b« riproduD*d wVnot &w
Tlik pcodct ooMn MnnafloniMdi bM bMO npnduoad wCh
pvTriHta^jTBoM byTTmai BraflMn Mipa.
3 Miles
PROJECT LOCATION
Kt^ie
ilOJMlA
weuA.
ai^je
County of San Diego
Hydrology Manual
Rainfall Isopluvials
10 Year Rainfall Event - 24 Honrs
Isopluvial (inches)
DPW
DspMrm of/bM? Mbcli
Stnfcor Wic Haw San Dicgo ilavctctil
THIS UAP B PRCMDQ) WTTKDUr WARRANTY OP ANV MND, BTHER E»>REBe
Oft (U3IA MCllJDOiQ, BUT NOT LUnro TO, THH WPUS) WARRANTTES
OF UERCHANiranJTY AW nTNBBe FOft A PMnvajLAR PURPOflE.
Oopyvf^ SmOa. Al RmtvkL
TTii pndudinqr oonUi WbnBaOon torn ffM SAWAO Haglaari[]fti—>inflliaNmwticfaoMnDtbarifiM!flu»diritoBtt»
Kfltm poraMon of &AWAO.
3 Miles
EQUATION
I - 7.44 ^6
I = Intensity (ItWhr)
^6 = 6-Hour Precipitation (hi)
D n Durafion (min)
SSSI!SSSSS!SmSSS5S
7 8 9 10 20 30
Minutes
Duratkwi
3 4 5 6
Hours
DIrectlona for Application:
(1) From predpltatton maps determine 6 hr and 24 hr amounts
for the selected frequency. These maps are included in the
County Hydrology Manual (10.50. and 100 yr maps inctuded
In (he Design and Procedure Manual).
(2) Arflust 6 hr precipitation (If necessary) so that It is within
ttie range of 45% to 65% of the 24 hr precipitation (not
appllcaple 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:
(a) Selected frequency I O year
(b) Pg = l.(oO in.. P24 = 3.00 = 53 %(2)
(c) Adjusted Pg<2) = l.fcQ in.
(ff) V" 5 mIn.
(e) I = 4*. 2.L. In./hf.
Note: This chart replaces the Intensity-Duration-Frequency
curves used since 1665.
[■71771 1 I ij
IS
a
"T5o
£12
las
1.30
1.08
0.93
oas
oao
0.53
a4i
0.34
0.29
3.18
2.S3
1.96
1.S2
1.40
1.24
1.03
0.90
0.S0
£9 I 3 I U I 4.5
4.24
3J7
2.69
2.15
\S7
1.36
1.19
1.06
a61 OM
0.51 0.S8
044 0.59
0J2
530
4.21
324
229
£33
£07
1.72"
1.49
1.02
023 043
OM
0'73OM
064
5.05
3.89
323
£80
£49
2.07
1.79
7.42
5.90
424
3.77
327
£90
£41
122
0.68 1.03
OSS' 076
6.74 I 7.M
5.19
421
3.73 I 42
3.322.76 jJi'lOj29j_^';£12 j£39|1. 63 ; f 84 I12<5"i i.M ['l.'ia' "1.32 i
13J7114.4910.60} 1J^'
8.42 ; 9.27049'r7.i3lH'OW J4.67 1 5.13 14.15 :"4.m1
3.45 . 3.79£98 i 3.28' I
IntofMlty-Duratlon Dealgn Chart - Tamplata 1 G V R E
3-1