HomeMy WebLinkAboutSDP 96-14C; LEGOLAND HOTEL CALIFORNIA; STORM WATER MANAGEMENT PLAN; 2008-09-02-----
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C 58673
Exp(;;,0,
CIV\\..
RECEIVED
SEP O 2 2008
CITY OF CARLSBAD
PLANNING DEPT
STORM WATER MANAGEMENT PLAN
For
LEGOLAND HOTEL CALIFORNIA
Carlsbad, CA
September 2, 2008
Prepared By:
Hofman Planning & Engineering
3152 Lionshead Ave.
Carlsbad, CA 92010
RCE 58873 Exp. 6-30-09
Prepared by: JC
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TABLE OF CONTENTS
1. INTRODUCTION
2. VICINITY MAP
3. PROJECT DESCRIPTION
3.1. Narrative of project activities
4. BMP SITE MAP (Figure 1)
5. POLLUTANTS AND CONDffiONS OF CONCERN
5.1. Anticipated Pollutants based upon land use (Table 1)
5.2. Receiving waters downstream
5.3. Carlsbad Watershed impaired water bodies downstream
5.4. Primary Pollutants of Concern
5.5. Impacts to hydrologic regime
6. CONDffiONS OF CONCERN
7. LID SITE DESIGN BMPS
7.1. (BMP-1) Minimize and disconnect impervious areas
7 .2. (BMP-2) Conserve Natural Areas
7 .3. (BMP-3) Minimize directly connected impervious areas
7.4. (BMP-4) Maximize canopy interception and water conserv.
8. Source Control BMP's
8.1. (BMP-11) Trash Storage Areas
8.2. Efficient Irrigation Systems & Landscape Design
8.2.1 (BMP-14) Rain shutoff devices
8.2.2 (BMP-15) Specific area water requirements
8.3. (BMP-17) Storm Water System Stenciling
9. BMP's for Individual Priority Project Categories
9.1. (BMP-22) Dock Areas
9.2. (BMP-26) Equipment Wash Areas
10. Structural Treatment BMP's
10.1. Extended Detention Basin
11. BMP MAINTENANCE PROVISIONS
ATTACHMENTS:
A.
B.
C.
D.
E.
303(D) list for impaired water bodies
Storm Water Standards Questionnaire
Source Control BMP's
Portion of Drawing 333-2Y
Extended Detention Basin TC-22
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Introduction
Federal, state and local agencies have established goals and objectives for storm water
quality. The proposed project, prior to the start of construction activities, will comply
with all federal, state and local permits including the National Pollutant Discharge
Elimination System (NPDES) permit, Order No. R9-2007-0001, NPDES No. CAS0108758
issued to the State Water Resources Control Board (SWRCB) on January 24, 2007.
The purpose of this SWMP is to address the water quality impacts from the proposed
improvements as shown on the Site Development Plan. This project will provide
guidelines in developing and implementing Best Management Practices (BMP's) for
storm water quality during construction and post construction.
A SWPPP may need to be prepared and approved prior to issuance of a grading permit.
The approved SWPPP shall be implemented during the construction phase. The SWPPP
will consist of the selected BMP's, guidelines and activities to carry out actions, which
will prevent the pollution of storm water runoff. The SWPPP will also include the
monitoring and maintenance of the construction of BM P's during the construction phase.
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2. VICINITY MAP
CITY OF OCEANSIDE
PACIFIC
OCEAN
CITY OF ENCINITAS
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I • I NOT TO
SCALE
CITY OF VISTA
Y OF
N MARCOS
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3. PROJECT
The site is wholly within the parking lot of Legoland California in the city of
Carlsbad (APN 211-100-14). The site is bordered by the park to the north and
the parking lot to the east west and south. The site is presently a paved parking
lot and decorative paving which will be removed.
The site currently drains to the south, into an existing private 36" PVC storm
drain. The runoff enters the storm drain through a series of curb inlets in the
existing parking islands.
3.1. Narrative of Project Activities
A new 3-story hotel building as well as incidental utilities, and hardscape
improvements is proposed within the parking lot at will span over the existing
pedestrian park entrance. As indicated on the Site Map, a new private
subsurface drainage system will convey the runoff around the hotel building into
the existing storm drain system.
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4. BMP SITE MAP
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5. POLLUTANTS AND CONDmONS OF CONCERN
5.1. Anticipated Pollutants Based on Land Use
There is no sampling data available for the existing site condition. The project
will contain some pollutants commonly found on similar developments that could
affect water quality. The following table is taken from the City of Carlsbad's
Storm Water Standards Manual. It includes anticipated pollutants for commercial
development.
Ta bl e 2. Ant1c1pate d d an • I II Potentia Po utants Generate db ,y Lan d Use Type.
General Pollutant Categories
~ Cl) 0) Cl) ~ ~ <..) "O C: .!: ~ C: >-, Cl) --C: ~ Cl) Cl) ro "' Project Cl) C: lo~ C: ::s ..c:::: ·c Cl) "O C: ~ Cl) --Cl) E Cl) ro o o, c: ro = :g ~ Cl) ·c:: Cl) Cl) 0) 0.. Cl) ..c >-. ro -Cl) ::s Categories '5 :5 ro cv XE Cl) 0 ~ ~5 I~ ~ E .= 0 Cl) z 0 0 0 Cl) -g (9 en (..) 0 C/) co
Detached
Residential X X X X X X
Development
Attached
Residential X X X X p (1) p (2) p (1)
Development
Commercial
X
X
Development p(1) p(1) p(2) X p(S) X p(3) p(S)
2 >100,000 ft
Automotive X x'4)(si X X Repair
Restaurants X X X X
Hillside
Development X X X X X X
2 >5,000 ft
Parking Lots p(1) p(1) X X p (1) X p(1)
Streets,
Highways & X p
(1)X X X (4) X p (5) X
Freeways
X = anticipated
P = potential
(1) A potential pollutant if landscaping exists on-site.
(2) A potential pollutant if the project includes uncovered parking areas.
(3) A potential pollutant if land use involves food or animal waste products.
(4) Including petroleum hydrocarbons.
(5) Including solvents.
5.2. Receiving Waters Downstream
The project drains to the Canyon de las Encinas Hydrologic Area (904.4) of the
Carlsbad Watershed.
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5.3. Carlsbad Watershed Impaired Waters Downstream
The Canyon de las Encinas Hydrologic Area is not identified on the most recent
303d list of impaired water bodies.
5.4. Primary Pollutants of Concern
Consequently, there are no primary pollutants of concern for this project.
6. Conditions of Concern
The proposed storm drain system has been designed so that the 100-year runoff
generated from the proposed development does not adversely impact the
downstream facilities any more than the existing condition. As the project is
wholly within Legoland California and will be incorporated into an established
storm drain network, there is no potential for downstream runoff. Moreover, the
proposed projects increases the overall perviousness and, consequently, reduces
the overall stromwater runoff generated.
7. LID Site Design BMP's
7 .1. (BMP-1) Minimize and Disconnect Impervious Surfaces
7.1.1. Building density has been maximized through a multiple-story design
subject to the City of Carlsbad's building height limitations.
7.1.2. The fire access lane will be constructed with an alternative semi-
permeable surface subject to the approval of the City Fire Marshall
7.2. (BMP-2) Conserve Natural Areas
7.2.1. The requirements of the design (specifically the required amount of
parking) limited the ability to conserve natural areas. However, trees and
other vegetation have been incorporated into the proposed project to the
maximum extent possible. All slopes and landscape areas are planted.
Moreover, additional landscaping has been added to the site with the
removal of a portion of the existing parking lot.
7.2.2. As shown on the Site Map, the existing parking islands and mounds as
well as their associative vegetation will be preserved
7.3. (BMP-3) Minimize and Disconnect Impervious Surfaces
7.3.1. The roof drains for the proposed hotel will be directed into the vegetated
areas.
7 .3.2. The proposed storm-drain inlets to the northeast of the hotel will be
situated in vegetated areas to facilitate biological treatment prior to
entering the drainage system.
7.4. (BMP-4) Maximize Canopy interception and water conservation
7.4.1. As shown on the Site Map, the existing parking islands and mounds as
well as their associative trees will be preserved.
7.4.2. The proposed trees will be drought tolerant.
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8. SOURCE CONTROL BMP'S
8.1. Trash Storage Areas {BMP-11)
The trash storage is to be paved with impervious concrete, sloped to not allow
run-off from adjoining areas, and walled and gated to prevent off-site transport
of trash and contain a roof or awning to minimize direct precipitation. The
individual containers will have attached lids that exclude rain to minimize direct
precipitation.
8.2. Efficient Irrigation Systems & Landscape Design
8.2.1. Rain shutoff devices shall be employed to prevent irrigation during
precipitation consistent with the Carlsbad Landscape Manual and specified
in the project's landscape plans. (BMP-14)
8.2.2. Irrigation systems will be designed to each landscape area's specific
water requirements consistent with the Carlsbad Landscape Manual and
specified in the project's landscape plans. (BMP-15)
8.3. Provide Storm Water System Stenciling
The design proposes permanent marking of all storm water conveyance system
inlets and catch basins within the project area with prohibitive language (e.g.,
"No Dumping -I Live Downstream'1, satisfactory to the City Engineer. (BMP-17)
9. BMP's FOR INDMDUAL PRIORITY PROJECT CATEGORIES
9.1. Dock Areas {BMP-22)
The existing site design has incorporated a drainage design to preclude urban
run-on and runoff onto the loading area
9.2. Equipment Washing Areas {BMP-26)
An area for outdoor equipment/accessory washing shall be self-contained,
covered, equipped with a pretreatment facility and properly connected to a
sanitary sewer.
10. STRUCTURAL TREATMENT CONTROL BMP'S
10.1. Extended Detention Basin
100% of the on site runoff has been and will continue to be ultimately conveyed
through an existing extended detention basin south of the parking lot next to
Palomar Airport Road, prior to entering the public storm drain system. This
extended detention basin is shown in detail on the City of Carlsbad's drawing
No. 333-2Y, Attachment D
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Sub-basins draining to the extended detention basin are expected to convey the
pollutants listed in section 5.1 of this report. An extended detention basin is an
effective treatment control BMP with maximum pollutant removal efficiency for
the particular pollutants of concern and provides water quality benefits from
filtration and infiltration. Moreover, this extended detention basin limits the
quantity of runoff entering the public stream. Additional information regarding
extended detention basins is shown on Attachment E.
11. BMP MAINTENANCE PROVISIONS
The proposed BMP's will be maintained by Legoland California. Contact: Chris Romero,
Maintenance Director, One Legoland Drive, Carlsbad, CA 92008, (760) 918-5460. The
existing extended detention basin is maintained by Legoland California and will continue
to be maintained by park maintenance on a regular basis.
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2006 CWA SECTION 303(d) LIST OF \VATER QUALITY LIMITED SEGMENTS REQUIRING TMDLS
REGION TYPE NAME
9 I{ Agua lledionda Creek
9 •: Agua llcdionda Lagoon
9 R Aliso Creek
SAN UIECO HECIONAL W,\TEH Ql/AI.ITY CONl'HOL UOAIW
CALWATER
WATERSHED
9043!000
90431000
90113000
PO LLUTANT/STRESSOR
l\lauganese
Selenium
Sulfates
Total Dissolved Solids
Indicator bacteria
Sedlmeutation/Slllalion
Indicator bacteria
POTENTIAL
SOURCES
Source Unknown
Source Unknown
Source Unknown
Urban Hunoff/Storm Sewers
Unknown Nonpolnt Source
Unknown point source
Nonpoinl/Point Source
Nonpoint/l'oint Source
liSIO:l'A ,\l'l'IHl\'Al. l>A n:: .JUNE 28, 2007
ESTII\IATED
SIZE AFFECTED
7 Miles
7 Miles
7 !\Illes
7 Miles
6.8 Acres
6.8 Acres
19 Miles
PIU)l'OSEI> Tl\ll>L
COMPLETION
2019
2019
2019
2019
2006
2019
2005
1Ms listing fur indit"alur ba<'lerit1 applies to the Aliso (hek 111ai11stt'111 and all the majvl' 1,-ibutaries ,,JA/isv Creek 1rhid1
are Sulphur Creek, Wvvd Canyon, Aliso I/ills Canyu11, Dai1J• Furk, and English Canyon.
l'hosphurus
Urban Runoff/Storm Sewers
Unknown point source
Noupolnl/Polnt Source
19 Miles 2019
77,is listing fur phusplwms applic.,· tu the Alisu Crak 111t1imte111 and all the majur tributaric,· u/Afoo Creek which are
S11/p/111r Creek, Wovd Cu11yv11, Aliso //ills Canyon, Dai,y Fork, and l:'11g/ish Canyon.
J'uge I t1/27
Urban Runoff/Slonu Sewers
Unknown Nonpoint Source
Unknown point source
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2006 C\VA SECTION 303(d) LIST OF WATER QUALITY LIMITED SEGMENTS REQUIRING Tl\'IDLS
JH:GION TYPE NAI\IE
9 E Aliso Creek (moulh)
9 L Danell Lake
9 n Huena Creek
9 n Huena Vista Creek
9 E Buena Vista Lagoon
SAN UIE(;O HE(;IONAL \\',\TEH QUALITY CONTHOI. IIOAIH>
CALWATEI(
WATEHSIJIW
90113000
9100000
90432000
9042!000
90421000
POI ,I ,UTANT/STHESSOH
Toxicity
POTENTIAL
SOUHCES
l/SEl'A Al'l'IHl\'AL UATlc: JUNE 28, 2007
ESTIMATED PROPOSED TI\IDL
SIZE AFFECTED COMPLETION
19 l\lilcs 2019
1his /isti11gji1r toxicity app/ie.1· to the Aliso Creek maim/em and all the 111<yor tributaries u/Alisu Creek which are
Sulp/1111· Creek, Wood Ct111yu11, Ali.lu 1/il/J Ca11yu11, LJai,y Furk. and ti,gli.lh Ca11yu11.
Urban Hunoff/Slorm Sewers
lJnkno,vn Nonpoinl Source
Unknown point source
Indicator baclcria 0.29 Acres 2005
Nonpolnt/l'oinl Source
Color 125 Acres 2019
Source Unknown
Manganese 125 Acres 2019
Source Unknown
pll 125 Acres 2019
Source Unknown
DUT 4.8 Miles 2019
Source Unknown
Nitrate and Nitrite 4.8 Miles 2019
Source Unknown
l'hosphale 4.8 Miles 2019
Source Unknown
Sediment Toxicity II l\liles 2019
Source Unknown
Indicator bacteria 202 Acres 2008
Nonpoinl/l'oinl Source
Page 1 of17
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2006 C\\'A SECTION 303(d) LIST OF \VATER QUALITY LIIVIITED SEGMENTS REQUIRING TMDLS
S,\N DIE(;() IU:(;IONAI. W,\Tl<:R QllALIT\' CONTIWL IIOAIW
lJSl•:l'A Al'l'IHIV AL l>ATF: JllNE 28, 2007
CAl,WATER POTENTIAL ESTIMATED PROPOSED TI\IDL
REGION 'J'YPE NAME WATERSHED POl.l,l/TANT/STRESSOR SOURCES SIZE AFFECTED COMPLETION
Nutrients 202 Acres 2019
E\·timal<'d size uf i11tpt1ir111c111 is 150 acrt'.\. locate,/ in upp,:r purtivn oflaguvn
Nonpoint/l'oint Source
Sedimentation/Siltation 202 Acres 2019
NonpoinUl'oint Source
9 R Chollas Creek 90822000
Copper 3.5 Miles 2004
Nonpoint/l'oint Source
Indicator bacteria 3.5 Miles 2005
NoupoinUl'oint Source
Lead 3.5 Miles 2004
NonpoinUPoiut Source
1.,Juc 3.5 Miles 2004
NonpoinUl'oint Source
9 R Cloverdale Creek 90532000
Phosphorus 1.2 Miles 2019
Urban Runoff/Storm Sewers
Unknown Nonpolnt Source
Unknown point source
Total Dissolved Solids 1.2 Miles 2019
Urban Runoff/Storm Sewers
Unknown Non1winl Source
Unknown point source
9 R Cottonwood Cn?ek (San Marcos Creek 9045IO0II
watershed)
DDT 1.9 Miles 2019
Source Unknown
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2006 C\VA S~:CTION 303(d) LIST OF WATER QUALITY LIMITED SEGMENTS REQUIRING TMDLS
REGION TYPE NAME
9 8 Dana Point Harbor
9 R De Luz Creek
9 L El Capitan Lake
9 R Encinitas Creek
SAN DIE<;o HEGIONAL WATER QUALIT\' CONTHOL IIOAIW
C\l,WATER
WATERSHED
90114000
9022!000
90731000
9045!000
POl,LUl'ANT/STRESSOR
Phosphorus
Sediment Toxicily
Indicator bacteda
POTENTIAL
SOURCES
Source l/nknown
Source Unknown
lmpairme11/ lu<.·a1ed al Baby Bcat..·h.
Iron
Manganese
Color
Manganese
pll
Phosphorus
P11ge 4 of 17
Urban Hunoff/Storm Sewers
Marinas and Recreational Boating
Unknown Non1•olnt Source
Unknown point source
Source Unknown
Source Unknown
Source Unknown
Source Unknown
Source Unknown
Source Unknown
IJSl<:PA Al'l'ltO\'AL 11,\TI<:: .llJNI•: 28, 2007
ESl'JMATED PROPOSED TI\IDL
SIZE AFFECTED COMPLETION
1.9 l\lilcs 2019
1.9 l\liles 2019
119 Acres 20U6
14 l\lilcs 2019
14 l\liles 2019
1454 Anes 2019
1454 Acres 2019
1454 Acres 2019
3 Miles 2019
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2006 C\VA SECTION 303(d) LIST OF WATER QUALITY LIMITED SEGMENTS REQUIRING TMDLS
REGION TYPE NAME
9 R English Ca11yo11
9 R Escondido Creek
9 t: •·a111osa Slough nnd Channel
9 R Felicita Creek
SAN DIE(;O IU:(;IONAL WATER QIIALITY ('ONTHOL IIOAIW
CALWATER
WATERSIIED
90113000
90462000
90711000
90523000
l'OLl,UTANT/STRESSOR
llcnzo( b J lluora II thene
llieldrin
Sediment Toxicity
DDT
Manganese
Phosphate
Selenium
Sulfates
Total llissolvcd Solids
Eutrophic
Aluminum
Puge 5 o/17
POTENTIAL
SOURCES
Source Unknown
Source Unknown
Source Unknown
Source Unknown
Source Unknown
Source Unknown
Source Unknown
Source l/11k11ow11
Source Unknown
Nonpoint Source
Source Unknown
l/Sl<'.l'A Al'l'IUl\'AL DATE: Jl/NE 28, 2007
ESTIMATED l'IHJPOSE0 TI\IOL
SIZE AFFECTED COMPLETION
3.6 l\liles 2019
3.6 l\lilcs 2019
3.6 Miles 2019
26 l\liles 2019
26 l\lilcs 2019
26 l\lilcs 2019
26 l\liles 2019
26 l\liles 2019
26 l\lilcs 2019
32 Acres 2019
0.92 l\liles 2019
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2006 CWA SECTION 303(d) LIST OF \\I ATER QUALITY Lll\11TED SEGMENTS REQUIRING TMDLS
REGION T\'l't<: NAME
9 R Forester Creek
SAN IJII':(;() HECIONAL \\'ATEH QUALITY CONTIWL llOAIW
CALWATER
WATERSIIEO
90712000
1'()1,1,l/TANT/STllESSOR
Tolal Uissolvcd Solids
Fecal Coliform
POTENTIAL
SOURCES
Agricullu.-al Rclurn Flows
Urban Runoff/Slorm Sewers
Flow Regulalion/Modificalion
Unknown NonJJoint Source
Unknown JIOint source
lmpuirme111 Located al lower I mile.
Oxygen, Dissolved
pit
Urban Runoff/Storm Sewers
Spills
Unknown Nonpoint Sou.-ce
Unknown polnl source
Source Unknown
Impairment Lvc<1tcd at upper 3 mil,•s.
l'hosphorus
Industrial Point Sources
llahilal l\lodificalion
s,,ms
Unknown Nonpoint Source
Unknown 11oint source
Source Unknown
Total Dissolved Solids
lm11airme11/ I.om/eel al lower I mile.
l'uge 6 ofl7
Agricullural Return Flows
U.-1,an Runoff/Storm Sewers
flow Regulalion/1\lodification
Unknown Non11oint Source
Unknown point source
USEI' A Al'l'ltO\' AL DATE: JUNE 28, 2007
ESTIMATED r1w1•0s•:u TMUL
SIZE AFl'ECTEU COMPLETION
11.92 l\lilcs 2019
6.4 l\liles 2005
6.4 l\liles 2019
6.4 l\liles 2019
6.4 l\liles 2019
6.4 l\liles 2019
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2006 CWA SECTION 303(d) LIST OF WATER QUALITY LIMITED SEGMENTS REQUIRING TMDLS
REGION TYPE NAI\IE
9 R Green Valley Creek
9 I, Guajome Luke
9 I, !lodges, Lake
SAN umc;o HE(;IONAI. W,\TEH QUALITY CONTIWL IIOAIW
<.:ALWATEH
WATERSIIED
90521000
90311000
90521000
POLl,UTANT/STR~:sson
Chloride
l\laugauese
l'cnlachlorophenol (PCP)
Sulfates
Eulrophlc
Color
Manganese
Nitroge11
l'uge 7 of27
POTENTIAL
SOURCES
Source Unknown
Source Unknown
Source Unknown
Urban Runoff/Storm Sewers
Natural Sources
Unknown Nonpoint Source
Unknon n point source
NonpoinUPoint Source
Urbau Runoff/Storm Sewers
Unknown Nonpoint Source
Unknown point source
Source Unknown
Agriculture
Dairies
llrhan Ru11off/Storm Sewers
Unknown Nonpoint Source
lJ11know11 poi11t source
LJSl•:l'A ,\l'l'IUIVAI. l>ATE: .HINE 28, 211117
ESHMATED l'IWPOSED TI\IDL
SIZE AFFECTED COMPLETION
0.98 l\liles 2019
0.98 l\liles 2019
11.98 l\liles 2019
0.98 l\liles 2019
JJ Acres 2019
1104 Acres 2019
1104 Acres 2019
1104 Acres 2019
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2006 CWA Sl~CTION 303(d) LIST OF \VATER QUALITY LIMITED SEGMENTS REQUIRING TMDLS
REGION TYPE NAME
9 R Kil Carson Creek
9 I{ Laguna Can}·on Channel
9 E Loma Alta Slough
SAN IJIEC;o nn;IONAL WATElt QlJALIT\' CONTUOI. IIOAIW
CAI.WATER
WATERSHED
90521000
90112000
90410000
P<>LLUTANT/STRESSOR
pll
Phosphorus
Turbidity
l'entachlorophenol (PCP)
Total Dissohed Solids
Sediment Toxicity
~:ulrophic
hulicalor bacteria
Page8 o/17
POTENTIAL
SOURCES
Source Unknown
Ag.-icullure
Vairies
Urban Runoff/Storm Sewers
Unknown Nonpoint Sou.-ce
Unknown point source
Source Unknown
Source Unknown
Agricultural lletuna Hows
U.-ban Runoff/Storm Sewers
!'low Rcgulation/1\lodiflcutlon
lfnknown Nonpolnt Source
Unknown point source
Source Unknown
Non1wi11t Source
Nonpoint Source
lJSEl'A ,\Pl'HO\'AL uxn:: .JUNE 28, 2007
ESTIMATED PIWPOSli:D TMUL
SIZE AFFECTED COMPLETION
1104 Acres 2019
1104 Acres 2019
1104 Acres 2019
0.99 l\1iles 2019
0.99 l\liles 2019
1.6 Miles 2019
8.2 Acres 2019
8.2 Acres 2008
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2006 C\VA SECTION 303(d) LIST OF WATER QUALITY Lil\1ITED SEGMENTS REQUIRING Tl\'IDLS
IU-:GION TYPE NAME
9 R Long Canyon Creek
9 R Los Penasquilos Creek
9 E Los Pcnas«1uitos L11goon
9 L l,oveland Uescrvolr
9 B l\lission Day (area al mouth of Rose Creek
only)
SAN uru;o l{E(;IONAL \\'ATEH (}l/AI.ITY CONTI{()(, IIOARU
CAl,WATER
WATERSIIED
90283000
90610000
90610000
90931000
90640000
l'(>IJ,UTANT/S'l"R!,;SSOH
Total Dissolved Solids
Phosphate
Total llissolnd Solids
Scdimentalion/Sillation
Aluminum
Manganese
Oxygen, Dissolved
pll
POTENTIAL
SOURCES
Source Unknown
Source Unknown
Source Unknown
Nonpoint/Point Source
Source Unknown
Source Unknown
Source Unknown
This listing was made by USEPA ji,r 1006.
Source Unknown
Eutrnphlc
Nonpoint/Polnt Source
Lelld
Nonpolnt/Poinl Source
Page 9tJjl7
1/Sl•:l'A Al'l'IH)\'AI. llATE: Jl/NE 28, 211117
ESTIMATED PIWl'USED TMDL
SIZE AFFECTED COMPI.ETION
8.3 l\lilcs 2019
12 l\liles 2019
12 l\lilcs 21119
469 Acres 2019
420 Acres 2019
420 Ac.-cs 2019
420 Acres 2019
420 Acres 2019
9.2 Acres 2019
9.2 Acres 2019
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I ' I I I • t I I I I I I • t I I I I • I I I I a • I I t I I I I I
2006 C\VA SECTION 303(d) LIST OF WATER QUALITY LIMITED SEGMENTS REQUIRING TMDLS
REGION 'l'YPE NAME
9 IJ Mission Hay (area at mouth of Tecolote
Creek only)
9 C l\lisslon Bay Shoreline
9 L l\lorena Reservoir
9 L l\lurr:t)' Reservoir
9 R l\lurricla Creek
SAN lllEGO IU:(:IONAL \\'ATElt QUALITY CONTROi. IIOAIU>
CALWATl<:R
WATERSIIED
90650000
90630000
91150000
907111100
90252000
l'OU,UTANT/STRF.SSOH
•'.utrnphic
Leatl
lntlicator bacteria
POTENTIAL
SOURCES
Nonpoint/Polnt Source
Nonpolnt/Point Source
11,is listing 11·as 11uu/e by USEPAfor 2006.
Source Unknown
Color
Source Unknown
Manganese
Source Unknown
pll
Source Unknown
pH
Source Unknown
Iron
Source Unknown
l\langancse
Source Unknown
Nitrogen
Source Unknown
Page /0o/17
USl<:l'A Al'l'IHJ\'AL l>ATI<:: .ll/NI•: 28, 20117
ESTII\IATED PROPOSED TMDI,
SIZE AFFECTED COMPLETION
J.I Acres 2019
J.I Acres 2019
28 Miles 2019
104 Acres 2019
104 Acres 2019
104 Acres 2019
119 Acres 2019
12 Miles 2019
12 Miles 2019
12 Miles 2019
• I
I I
I I I I t • I I I I • • I I I I I I I j J a i t I I I • I I I I I I
2006 C\\' A Sl~CTION 303(d) LIST OF WATER QUALITY LIJ\1ITED SEGMENTS REQUIRING TMDLS
REGION TYPE NAI\IE
9 R Oso Creek (al Mission Viejo Golf Course)
9 L Olay Rese.-voir, Lower
9 C l'acilk Ocean Shoreline, Aliso IISA
SAN l>IECO HECIONAL W,\TEH QUALITY CONTIHlt. IIOAIH>
CALWATER
WATERSHED
90120000
910.H000
90113000
POI.LlJT ANT/STIU:SSOR
Phosphorus
Chloride
Sulfates
Total Dissolved Solids
Color
Iron
Manganese
POTENTIAL
SOURCES
Urban Runoff/Storm Sewers
Unknown Nonpoinl Source
Unknown point source
Source Unknown
Source Unknown
Source Unknown
Source Unlrnown
Source Unknown
Source Unknown
Nitrogen, ammonia (Total Ammonia)
Source Unknown
pll (high)
Source llnknuwn
Indicator bacteria
USl".I',\ ,\l'l'ltOVAL DATE: .IUNI-: 28, 2007
ESTIMATED l'ROl'OSED Tl\ll)L
SIZE AFFECTED COMPLETION
12 Miles 2019
I Miles 2019
I Miles 2019
I Miles 2019
1050 Acres 2019
1050 Acres 2019
1050 Acres 2019
1050 Acres 2019
1050 Acres 2019
0.65 l\liles 2005
l111pair111e111 located at Lag1111a Beach at Lag1111ira Place I Blue Lagvon !'lace. Aliso IJ,,ac/1.
Nonpoint/Poinl Source
/'age II 11/ 2 7
I a
I I
I I I • I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I
2006 CWA SECTION 303(d) LIST OF \VATER QUALITY LIMITED SEGJ\'IENTS REQUIRING TMDLS
REGION TYPE
9 C
9 C
9 C
9 C
9 C
9 C
9 C
NAI\IE
Pacific Ocean Shoreline, lluena Vista Creek
IIA
Pacific Ocean Sho.-cline, Dana Point USA
Pacific Ocean Shoreline, Escondido Creek
IIA
l'acilic Ocean Sho.-clinc, l11111erial llcach
Pier
Pacific Ocean Shoreline, Laguna Reach
IISA
Pacific Ocean Shoreline, 1,oma Alla HA
Pacific Ocean Shoreline, Lower San Juan
IISA
SAN l>IECO IU:C;IONAL \\'ATER QUALITY CONTROL llOAIW
CALWATER
WATERSIIEI>
90421000
90114000
90461000
9111111000
90112000
90410000
90120000
POLLUTANT/STltESSOJt
Indicator bacteria
POTENTIAL
SOURCES
us1,:1•A Al'l'ltOVAL UATE: JUNE 28, 2007
ESTIMATED PIH>POSEI> TI\IDL
SIZE AFFECTED COMPLETION
1.2 l\liles 2008
/111pain11e111 located at Buena Vista C, eek, Car/shad City /Jeach al Curlshud Village D1fre, Carll-had State Beach al Pine
A,·e1111e.
Nonpoint/Point Source
Indicator bacteria 2 Miles 2005
lmpairmmt located ,1/ Alisu Beach at West Street, Aliso Bea,·h at Table Ruck Dri1·c. /000 Steps Beach at l'a,'ific' Coast
1/wy (llo.,pital, 9th ,h'e). S<J/t Creek (large outlet). Salt C,-"',k Beach at Salt Creek serrh·e rua.l, S<1lt Creek Beach at
Da11<1 S11..uul Road, and Alu11,1rcl1 Beach.
Nonpoinl/l'oint Source
Indicator bacteria 0.44 l\liles 2008
lm11air111e11t /ocuted al Su11 Elijo Lagoo/I outlet.
Nonpoinl/Point Source
l'CHs (l'olychlorinaled biphenyls) 0.42 l\liles 2019
Soun·e Unknown
Indicator baclcria 1.8 l\lilcs 2005
lmpairmrnl lm·t1ted t1I Main Laguna Bet1ch, Lagrma Beach ti/ <kean Are1111e, Lt1g1111c1 Brnch at l.agu11a A1•e1111e. Laguna
Beach al Cleo Street. Arch Cm•e al Bluebird C.111_1•un Ruad, Laguna Beach al Du111011d Dri1•e.
Nonpoinl/Point Source
lndicalor bacteria I.I l\liles 2008
lmpairme/11 located ut Loma A/tu Creek Mouth.
Nonpoint/Point Source
lndlcalor bacteria 1.2 l\lilcs 2008
/111pair111e11/ lo<·ated at Nor//, /Jead, Creek, Sa11 J11a11 Creek (h11ge outlc:1), Capistra11u Beach, Sor,//, Capi.rtm110 Beach at
8f'c1cl1 /load
Nonpoinl/l'oinl Source
/'age 12 of 27
I I
I I
I I I I I I
I I I I I I I I I I I I I I I I I I I I I I I I I I I •
2006 CWA SECTION 303(d) LIST OF \VATER QUALITY Lll\UTED SEGMENTS REQUIRING TMDLS
REGION TYPE
9 C
9 C
9 C
9 C
9 C
9 C
9 C
NAI\IE
l'acilk Ocean Shoreline, San Clcmcnle IIA
Pacific Ocean Shoreline, San lliego lllJ
Pacific Ocean Shoreline, San lliequilu Ill!
l'acilic Ocean Shoreline, San Joa11uin Hills
IISA
Pacific Ocean Shoreline, San Luis Rey Ill!
Pacific Ocean Shoreline, San Marcos IIA
Pacific Ocean Shoreline, Scri11ps IIA
SAN l>IE(;(l HE<:tONAL \\',\Tl-:R (JlJALIT\' CONTIWL HO.\IW
CALWATER
WATERSIIED
9Ul301J00
90711000
90511000
90111000
90311000
90451000
90630000
POLLlJTANT/STRESSOR
lndicalor bacleria
POTENTIAL
SOURCES
l/SEPA .-\1'1'1{0\'AL UATE: .ll/NI•: 28, 2007
ESHMATEI> l'IWPOSEIJ Tl\ll>L
SIZE AFF'ECTED COI\IPL.ETION
3,7 l\liles 2005
lmpC1irme111 located <1/ Poche Beach (large o,,t/e/J, Ole //a11s011 Bee1ch ( 'luh Beach ul Pico Urni11, Sun Cleme111e City
Beach al El Portal SI. Sluirs. San C/eme11te City Beach at /lfuriposa St., San Cle111t!11/e City Beach al Linda Lu11e. SCln
Cleme11/e City Beucl, al South U11<lt1 I.one, San Clemente Cily Beach at Lifeguard I /eadquarters. U11<ier Sa11 Cle111e11te
A1w,icipa/ Pil'r, S,m Clemente Ci~J' Beach at l'raji.1/gar C,mJ'On (lh!falgar l.11.), S,111 C/e111c11te S1t1lc Bea, I, al Rfricra
Beach, Sau Ch-111,mtc State Beach at ( 0J1>n!SS Shores.
NonpolnUl'oint Source
lndicalor bacleria 0.37 l\lilcs
!111pairme11t lucated ,1/ San Diego Ril-cr llfouth (aka Dog Bct1c/,).
NonpoinUPoinl Source
lndicalor baclerla 0,86 l\liles
!111pair111e11I localed al San Oieguito Lagoo// Alo111h, Solcma Beach.
Nonpoinl/Poinl Source
lndlcalor bacleria 0.63 /\Illes
/mpuin11e111 located al Cameo Co'1e al Irvine C,we LJr./Rivieru lfuy. Jleislt!r Park-North
Urban Runoff/Slorm Sewers
Unknown Nonpoinl Source
Unknown poinl source
Indicator haclerla 0,49 Miles
lmpairme11/ lo,·ated al San Luis Rey lli1•ff Afouth.
NonpolnUPoinl Source
lndicalor baclcria 0,5 l\lilcs
/111pair111e11I located al /\foonlight Slate Bead,.
NonpolnUPoinl Source
lndicalor buclc.-ia 3.9 l\lil<'s
2005
21105
2005
2005
2005
2019
This listing/or i11dic,l/or baderia onliy applies tu the Childl"£'11s l'uol Bt.'ach <1/'t'a o/ this oct.',111 slwreli11,· S<'gmclll.
NunpoinUl'oinl Source
l'uge 13 of 2 7
I I
I I I I I I I t I I I I I I I I I I I I I I I I I I I I I I I I I I I I I
2006 C\\' A SECTION 303(d) LIST OF WATER QUALITY LIMITED SEGMENTS REQUIRING Tl\tlDLS
SAN l>IE(;O HECIONAL WATEH QLJAUTY CONTHOL IIOAIW
USEl'A Al'PltOVAL DATE: Jl/NE 28, 2007
CAUVATER POTENTIAL ESTI I\IA TED PIHWOSED TI\IDL
REGION TYPE NAI\IE WATERSIIED POLLl/TANT/STHESSOR SOl/HCES SIZE Al'l-'ECTF.11 CUI\II'LETION
9 C l'acific Ocean Shoreline, Tijuana Ill/ 91111000
Indicator baclcria J l\lilcs 20!0
I//IJ}{litmt'11/ locatedfro111 /he border, ntendi11g nor//, along the .1/wre.
Nonpoint/Point Source
9 R Pine Valley Creek (lipper) 9114!000
Enlcrucoccus 2.9 l\liles 20!0
(;razing-Related Sources
Concentrated Animal Feeding Opcralions
(pcrruiUcd, point source)
Transient encampments
Phosphorus 2.9 l\liles 2019
Soune Unknown
Turbidily 2.9 l\liles 2019
Source Unknown
9 R Pogl Canyon Creek 9!020000
DOT 7.8 l\lilcs 2019
Source Unknown
9 R Pl'ima Deshecha Creek 9000000
Phosphorus 1.2 l\liles 2019
Urban Runoff/Storm Sewers
Unknown Non point Source
Unknown poh1t source
Turbidity 1.2 l\lilcs 2019
U1·ban Runoff/Storm Sewers
Unknown Nonpoint Source
Unknown point soul'Ce
9 n Rainbow Creek 90222000
Iron 5 l\lilcs 2019
Source Unknown
l't1ge /.I llfl7
I I I I I I • • I I I I I I I l I I I I I I I I I i I t I • • i t I I
2006 C\VA SECTION 303(d) LIST OF WATER QUALITY Lll\11TED SEGMENTS REQUIRING TMOLS
REGION TYPE NAME
9 R Reidy Can)'OII Creek
9 B San Diego Hay
9 B San Diego Bay Shoreline, J2nd SI San
Diego Naval Slalion
9 B San Diego Bay Shoreline, al Americas Cup
Harbor
9 B San Diego Hay Shoreline, al llayside Park
(J Street)
9 B San Diego Bay Shoreline, al Coronado Cays
SAN IJIEC;o REGIONAi. \\'ATER Ql/ALITY CONTROL llOAIW
CALWATER
WATERSHED
90462000
9101UOOO
90822000
90810000
9091 JOOO
91010000
PO LLIJT ,\ NT/STRESSOR
Sulfales
Tolal Dissolnd Solids
Phosphorus
POTENTIAL
SOUHCES
Source Unknown
Source Unknown
Source l/uknown
PCBs (Polycltlorinalcd blphenyls)
Source Unknown
llenlhlc Communily Effrcls
Nonpoinl/Poinl Source
Sedimenl Toxicily
Nonpolnl/Poinl Source
Copper
Source Unknown
lndicalor bacteria
This li.,ti11g was made by USEPA ji,r 2006,
Source Unknown
Copper
Source Unknown
J'age I 5 of 17
U~EI'.\ Al'l'IH>VAL UATE: .JUNE 28, 2007
ESTIMATED PIWPos•:o TMDL
SIZE AFFECTED COMPLETION
5 Miles 2019
5 !\lites 2019
3.9 !\lites 2019
10783 Acres 2019
IOJ Acres 2019
IOJ Acres 20 I 9
88 Acres 2019
50 Acres 2019
47 Acres 2019
• I
I I I I I I I I I I I I • • I I t I I ' 1 I I I I I I I I I I I I I I I
2006 CWA SECTION 303(d) LIST OF \VATl~R QUALITY LIMITED SEG1\-1ENTS REQUIRING TMDLS
REGION TYi'~:
9 B
9 B
9 B
9 H
9 B
NAME
San Diego Uay Shoreline, al Gloriella Hay
San Diego Bay Shoreliue, al Harbor Island
(East Basin)
San Diego Bay Shoreline, at Harbor Island
(West Basin)
San Diego Bay Shoreline, at Marriott
Marina
San Diego Bay Shoreline, behveen Sampson
and 28th Streets
SAN un:c;o HECIONAL \\'ATEH QUALITY CONTUOL IIOAIW
CAI.WATER
WATERSHED
910!0000
91182!000
90810000
90821000
90822000
POTENTIAL
1'O1,LUTANT/STRESSOR SOURCES
Copper
Source Unknown
Copper
Source Unknown
Cop11er
Source Unknown
Copper
Source Unknown
Copper
Nonpolnt/l'oint Source
Mercury
Nonpoint/l'oint Source
I' Alls (Polycyclic Aromatic Hydrocarbons)
Nonpoinl/l'oint Source
PC Us (Polychlorinated biphenyls)
Nonp11i11UPolnt Source
Zinc
NonpoinUl'oint Source
Page 16 of17
IJSl-'.l'A APl'IUl\'AL llATE: .llJNE 28, 2007
ESTIMATED PltOl'OSED TMDL
SIZE AFFECTED COMPLETION
52 Acres 2019
73 Acres 2019
132 Acres 2019
24 Acres 2019
53 Acres 2005
53 Acres 2006
53 Acres 2006
53 Acres 2019
53 ,\cres 2019
I I
I I
I I I I I I I • I
I I I I I I I I I I I I j I I j t I I I j a t • I
2006 CWA SECTION 303(d) LIST OF WATER QUALITY LIMITED SEGMENTS REQUIRING TMDLS
REGION TYl'E
9 C
9 B
9 C
9 B
9 B
9 B
NAI\IE
Sau Diego Bay Shoreline, Chula Vista
l\fariua
Sau Diego Bay Shoreline, Downtown
Anchorage
Sau Diego Bay Shoreline, G Street Pier
San Diego Bay Shoreline, near Chollas
Creek
San Diego Bay Shoreline, nur Coronado
Bridge
San ()iego Bay Shoreline, near sub base
SAN l>IECO IU:CIONAI. \\',\TEI{ QI/Al.IT\' CONTl{OI. IIOAHU
CALWATER
WATERSHED
90912000
90821000
90821000
90822000
90822000
POLLUTAN'f/STRl£SSOR
Copper
llenthic Community Effecls
Sediment Toxicity
Indicator baclerla
Benthlc Community Effects
Sediment To1icity
Benthic Community Effects
Sediment Toxicity
POTENHAL
SOURCES
Source Unknonn
No11poi111/Point Source
Nonpolnl/Point Source
Urban Runoff/Storm Sewers
Unknown Nonpolnt Source
Unknown point source
Nonpoint/Point Source
Nonpolnt/Point Source
Nonpolnl/Point Source
lJSl.:t'A Al'l'l{O\',\I, l),\TI~: JI/NE 28, 2007
ESTIMATED
SIZE AFFECTED
0.41 l\lilcs
7.4 Acres
7.4 Acres
0.42 l\liles
15 Acres
15 Anes
37 Acres
37 Acres
PHOPOSED Tl\lDL
COI\IPLETION
2019
2019
2019
2006
2006
2006
2019
2019
/11dudcs CrosbJ· Stree1/Cesar Ch,11·ez Park area, tlwt will receive additio11al 111011itoring.
Nonpoint/l'oint Source ,
90810000
Ucnthic {'ommunily Effecls 16 Acres 2019
No1111oinl/l'oint Source
Sediment Toxicity 16 Acres 2019
Nonpoinl/l'oint Source
Page /7"/17
I
I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I
2006 CWA SECTION 303(d) LIST OF \VATER QUALITY LIMITED SEGMENTS REQUIRING TMDLS
REGION TYPE
9 H
9 B
9 B
9 C
NAME
San Diego Hay Shoreline, near Swiller
Creek
San Diego Hay Shoreline, Norlh or 24111
Slreet Marine Terminal
San Diego Bay Shoreline, Seventh Slreel
Channel
San Diego Bay Shoreline, Shelter Island
Shoreline Park
SAN DIE(;o 1u:c;10NAL WATER QIJ,\LIT\' CONTROL HOAIU>
CALWATER
WATERSHED
90821000
90832000
90831000
908l0000
POI,I,UTANT/STRESSOR
Chlordane
POTENTIAL
SOURCES
Urban RunoWStorm Sewers
Other
Boatyards
NonpolnUPoint Source
I,indane/Ilexachlorocyclohexane (IICII)
Urban Runoff/Storm Sewers
Other
Boatyards
NonpoinUl'oint Source
PAIis (Polycyclic Aromatic llydrncarbons)
Uenthic Community Errecls
Sediment Toxicity
Bentltic Community Errects
Sediment Toxicity
Indicator bacteria
P,,ge 18 11/ 27
Urban Runoff/Storm Sewers
Other
Hoalyanls
Nonpoint/Point Source
Nonpoint/Point Source
Non110l11Ul'oint Source
NonpoinUl'oint Source
Nonpoinl/l'oinl Source
Unknown Nonpoint Source
Unknown point source
USEl'A Al'l'IHl\'AI, UATE: JUNE 28, 2007
ESTIMATED PIWl'OSED TMDL
SIZE AFFECTED COMPLETION
5.S Acres 2019
5.5 Acres 2019
S.S Acres 2019
9.S Anes 2019
9.5 Acres 2019
9 Acres 2008
9 Acres 2008
0.42 Miles 2006
I I
t I a • I I I I I I I • t t 1 I i I 1 I • i I I I I I I I I I I I
l
2006 c,v A SECTION 303(d) LIST OF WATER QUALITY LIMITED SEGMENTS REQUIRING TMDLS
REGION TYPE
9 D
9 R
NAME
San llicgo Day Shoreline, \'icinily of D SI
and Hruadway Piers
San Diego RiHr (Lower)
SAN DIEGO 1u:c;10NAL W,\TER QlJAUT\' CONTIWL ll0,\IW
CALWATER
WATERSIIED
90821000
90711000
1'01,LU'fAN'f/S'fHESSOR
llcuthlc Commuuily Effects
POTENTIAL
SOURCES
No11poi111/l'oi11I Source
lndic11tor hacle.-ia
E<timated size o(i111pair111e11/ is 0.4 miles aro1111d the slwreli11e olthe hay.
Sediment Toxicity
Fecal Coliform
Lou-er 6 miles.
Low Dissolved Oxygen
Urban Runoff/Storm Sewers
Unknown Non11oint Soune
Unknown point source
Nonpoinl/l'ohal Source
Urban Runoff/Storm Sewers
Wastewater
Nonpoinl/l'oint Source
l111pair111e11/ tra11sn!lldr a,(iace/11 ( 'al,rnter wtareshed 90712.
Phosphorus
Urban Runoff/Storm Sewers
Unknown Noupoint Sou.-ce
Unknown point source
!1111J/1irme1111n111sce11ds adjan:111 Co/waler >mlashed 90712.
Total Dissolved Solids
Urban Runoff/Storm Sewers
Unknown Nonpoint Source
llnknown point source
!mpairmelll tr<111sce11ds adjace111 Caliraler wotcrshcd 90 712.
P11ge 19 t1f27
Urban Ruuoff/Slorm Se,vcrs
Flow Regulalion/1\lodificution
Natural Sources
Unknown Nonpoinl Source
Unknown point source
IJSEl'A ,\Pl'IH)\',\L DATE: .JUNE 28, 2007
ESTIMATED
SIZE AFFECTED
9.9 Aucs
9.9 Acres
9.9 Acres
16 l\liles
16 l\lilcs
16 Miles
16 Miles
PROPOSED 'l'I\IDL
COMPLETION
2019
2006
2019
2005
2019
2019
2019
f
I I I I I I I I I I I I I i j i I I I I t I t I I I I I I I I I I I
2006 CWA SECTION 303(d) LIST OF \VATER QUALITY LIMITED SEGMENTS REQUIRING TlVIDLS
REGION TYPE NAI\IE
9 E San Elijo Lagoon
9 R San .Juan Creek
9 E San Juan Creek (mouth)
'I It San Luis ltey River
SAN IHE<;o IU:(;IONAI. W,\TElt QUALITY CONTROL IIOAIW
CAUVATER
WATERSHED
90461000
90120000
90120000
'10311000
POLLl/T ANT /STR[SSOR
Eutruphic
POT[NTIAL
SOURCES
fati111<1tt'd size of i111J1llin11en/ is ]JI/ acres.
Nonpoint/Point Source
Indicator bacteria
Estimated size of illlf'llirmenl is 150 acres.
Nonpoint/Point Source
Sedimentation/Siltation
Estimated size ofimpairtllt'lll is I 50 acres.
Nonpoint/Point Source
DDE
Source Unknown
Indicator bacteria
Nonpolnt/l'oint Source
Indicator bacteria
Nonpoinl/Point Source
Chloride
Impairment located al lower I 3 mile.r.
l'uge 10t1f27
Urban Runoff/Storm Sewers
l/11k11ow11 Nonpoint Source
Unknown point source
IJS~:l'A Al'l'IH)\'AI. UA·n:: .JUNI/ 28, 2007
ESTIMATED PROPOSED TMDL
SIZ[ AliF[CTF.D COl\11'1,ETION
S66 Acres 2019
S66 Acres 2008
S66 Acres 2019
l l\lilcs 2019
I l\liles 200S
6.3 Acres 2008
19 l\llles 2019
I •
I I • • I I I I I t I I i i j I t i j I I ' I I j t I I • I I t i I
2006 C\VA SECTION 303(d) LIST OF \VATER QUALITY LIMITED SEGMENTS REQUJIUNC TMDLS
REGION TYPE NAME
9 R San Marcos Creek
9 I, San l\lai-cos Luke
9 L San Vicente Reservoir
SAN l>IE(;o IU:(;IONAI. WATER (}l/ALITY CONTIHlL 110,\lll>
CALWATER
WATERSHED
9045!000
90-152000
907211100
POLLUTANT/STRESSOR
Total Dissolved Solids
ODE
Phosphorus
Sediment Toxicity
Ammonia as Nitrogen
Nnlrlents
Phos11horus
Chloride
Page 11 of17
POTENTIAL
SOURCES
lmluslrlal Point Sources
Agriculture-slorm runoff
Urban Runoff/Storm Sewers
Surface !\lining
Flow Regulation/Modification
Natural Sources
Golf course activities
Unknown Nonpolnt Source
Unknown point source
Source llnlrnuwn
Source Unknown
Source Unknown
Source Unknown
Source Unknown
Source Unkno,vn
Source Unknown
USl•:l'A ,\l'PIUl\'AL ll,\TI•:: .JUN(( 28, 211117
ESTIMATED PROPOSED TMl>L
SIZE AFFECTED COMPLETION
19 Miles 2019
19 l\llles 2019
19 Miles 2019
19 Miles 2019
17 Acres 2019
17 Acres 2019
17 Ac.-es 2019
1058 Acres 2019
t i
I I I I I I I I I I I I i I t I I I I I I I I I I I I I I I I I I I I I
2006 CWA SECTION 303(d) LIST OF WATER QUALITY LIMITED SEGMENTS REQUIRING TMDLS
REGION TYPE NAME
9 R Sandia Creek
9 E Santa l\largarila Lagoon
SAN UIEGO HEGIONAI. W,\TEH QlJAI.ITY CONTHOL IIOAIW
CALWATER
WATERSIIED
90222000
90211000
POU,llTANT/STUESson
Color
Manganese
pll (high)
Sulfales
Iron
Manganese
Nitrogen
Sulfates
Tohd Dissolved Solids
Eu1ro.,hic
r,,c,· 11 ,,,. n
POTENTIAL
SOURCES
Source Unknown
Source Unknown
Source Unknown
Source Unknown
Source Unknown
Source l/nknowu
Source llnknown
Source Unknown
Urban Runoff/Storm Sewers
filow Rcgulalion/1\lodificalion
Natural Sources
Unknown Nonpolnl Source
l/11k111nv11 l'oinl source
Nonpoinl/l'oint Sou1-cc
llSl•:l'A Al'l'RO\'AL IUTE: .JUN!<: 28, 2007
ESTIMATED l'ROl'OSED TMDL
SIZE AFFECTED COMPLE'CION
1058 Acres 2019
1058 Acres 2019
11158 Acres 2019
1058 Acres 2019
1.5 Miles 2019
1.5 Miles 2019
1.5 l\lilcs 2019
1.5 Miles 2019
1.5 l\llles 2019
28 Acres 2019
I I
I I
i I I I i t i I l
I I I I I I I I I I i t I I i I i t i t t
2006 CWA SECTION 303(d) LIST OF \YATER QUALITY LIMITED SEGMENTS REQUIRING TMDLS
REGION TYl'E NAME
9 R Sanla l\largarila IUver (Upper)
9 R Segunda Deshecha Creek
9 R Soledad Canyon
9 L Sutherland Rese.-voir
SAN l)lt,:(;O HE(;fON,\L \\',\TEH (}U,\I.ITY CONTl!OL IIOAIW
CALWATER
WATERSIIIW
90222000
90130000
906!0000
90553000
POLl,UTANT/STRESSOR
Phosphorus
Phosphorus
Turbidity
Sediment Toxicity
Color
Manganese
pH
Pllge 13 of17
POTENTIAL
SOURCES
Urban Runoff/Slorrn Sewers
l/11k11ow11 No11point Source
llnknown point source
llrban Runoff/Sturm Sewers
llnknown Nonpoiut Source
llnknown point source
Construcliou/Land Development
Urban Runoff/Sturm Sewers
Channelization
Flow Regulallon/1\lodiflcalion
l111know11 Nonpoint Source
llnknown poinl source
Source Unknown
llrbnn Runoff/Storm Seiters
Unknown Nonpoinl Source
llnknown point source
Source Unknown
Source Unknown
IJSl•:l'A Al'l'IHl\'AL IJATE: JUNE 28, 2007
ESHMATED PROPOSED TMDL
SIZE AFFECTED COMPLETION
18 l\liles 2019
0.92 Miles 2019
0.92 l\liles 2019
1.7 l\liles 2019
561 Acres 2019
561 Acres 2019
561 Acres 2019
I I I I I t I t i t I I I I I I I • • l I I i I i ' t I j • i t I
2006 CWA SECTION 303(d) LIST OF WATER QUALITY Lll\11TED SEGMENTS REQUIRING TJ\IIDLS
IIEGION TYPE NAME
9 L Sweetwater Reservoir
9 n Tecolote Creek
9 R Temecula Creek
SAN 1>1Ec;o l(EGIONAL WATEH QlJAIJTY CONTHOI. IIOAIU>
CALWATER
WATERSIIED
9092IO00
90650000
90251000
POJ,l,lJTANT/STRESSOR
(h)·gen, Ulssol\'ed
Cadmium
Copper
Indicator bacteria
Lead
Phosphorus
Toxicity
Turbidity
Zinc
Nitrogen
Phosphorus
Puge U"/17
POTENTIAL
SOURCES
Source Unknown
Non point/ Point Source
Nonpoint/Point Source
Nonpoint/Point Source
Nonpolnt/Polnt Source
Source Unknown
Nonpoint/Point Source
Source Unknown
Non11oinl/Polnt Source
Source Unknown
Source Unknown
1/SI•:l'A ,\l'l'HOVAL I>ATE: JI/NI•: 18, 2007
ESTIMATED PROPOSED TMDL
SIZE AFFECTED COMPLETION
915 Acres 2019
6.6 Miles 2019
6.6 Miles 2019
6.6 Miles 2006
6.6 l\liles 2019
6.6 l\liles 2019
6.6 l\liles 2019
6.6 Miles 2019
6.6 !\lites 2019
44 l\lilcs 2019
44 l\lilcs 2019
I I
I I I I I
I I I I I I I I I I I • I I I I * I I I I I I i I I I I I
2006 C\VA SECTION 303(d) LIST OF WATER QUALITY LIMITl~D SEGMENTS REQUIRING TMDLS
nEGION TYPE NAME
9 R Tijuana lli\'er
9 E Tijuana River Estuary
SAN l>IE(;O HECIONAL W.\TEH QUALITY CONTIWL 110,\IW
CALWATER
WATERSHED
91111000
91111000
1'01,LUTANT/STnESS(>lt
Total Dissolved Solids
Eu trophic
Indicator bacteria
Low DlssolHd Oxygen
Pesticides
Solids
Synthetic Organics
Ti-ace Elements
Ti-ash
Eutrophic
POTENTIAL
SOURCES
Source Unknown
NonpoinUl'oint Source
Nonpoinf/Point Source
NonpoinUPoint Source
Nonpoinf/Point Source
NonpoinUl'oinl Source
Nonpoint/Point Source
Nonpoint/Point Source
Nonpoint/Point Source
E\·/imated size ofimpair111e11t is I acre.
N1111pulnt/l'ol11t Source
Indicator bacteria
E,timated size ,!{i111paim1enl is 150 acres.
Nonpoint/Point Source
l'11ge 15 tJf17
l/SEPA APPROVAL 0.'HE: Jl/NI-: 28, 20117
ESTIMATED
SIZE AFFECTED
44 l\lilcs
6 l\liles
6 l\liles
6 l\liles
6 Miles
6 l\llles
6 l\lilcs
6 l\lilcs
6 J\llles
1319 Acres
1319 Acres
PROPOSED TMDL
COMPJ,ETION
2019
2019
2010
2019
2019
2019
2019
2019
2019
2019
2010
I I
I I
I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I
2006 CWA SECTION 303(d) LIST OF WATER QUALITY Lll\UTED SEGl\1ENTS REQUIRING TMDLS
REGION TYPE NAI\IE
SAN UIE(;() nn;IONAI. W,\TElt Ql/.-\LIT\' CONTHOI, llOAIW
CALWATER
WATERSHED l'OLl,llTANT/STRESSOR
Lead
POH~NTIAL
SOURCES
E5timated size <l impairment is I acre.
Low Dissoh·ed Oxygen
Nickel
NonpoinUPoint Source
1/rban Runoff/Storm Sewers
Wastewater
Unknown Nonpoiut Soul'Ce
Unknown point source
Eslimated size of i111p,1irment is I acre.
Non poinUPoint Source
Pesticides
Ertimatecl size of imJhlirment is I ac:re.
Nonpoint/l'oint Source
Thallium
Estimated size ofimp,1i,-menl is J acn.:.
Nonpoint/l'oint Source
Trash
EJtimaled size ,if imp,1ir111e111 is I acre.
Nonpoint/Point Source
Turbidity
Source Unknown
1'11ge 16 o/17
l/SEl'A Al'l'IU)\'AL l>ATE: JUNE 28, 2007
ESTIMATED l'IH>POSEO TMDL
SIZE AFFECTED COl\1PLETION
1319 Acres 2019
1319 Acres 2019
1319 Acres 2019
1319 Acres 2019
1319 Acres 2019
1319 Acres 2019
1319 Acres 2019
I I
I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I I
2006 CWA SECTION 303(d) LIST OF WATER QUALITY LIMITED SEGMENTS REQUIRING Tl\ilDLS
SAN l>IE(;() nn;10NAI. WATEH QIJAUT\' ('ONTHOI. IIOAIW
lJSl•:l'A ,\l'l'RO\'AL l>,\'I E: .IUNE 211, 2U07
ESTIMATED l'IH>POSED l'l\ll>L
REGION TYPE NAl\lE
CAI.WATER
WATERSIIED l'OU,UTANT/STRF.SSOR
POTENTIAL
SOURCES SIZE Al-'FECTED COJ\tl'LETION
r-----
liEGIONAL WATER QUAl.fJ\'_CO!l[r!!UL BOARDS
North Coast
2 San Francisco Bay
3 Central Coast
4 Los Angeles
5 Central Valley
6 Lahontan
7 Colorado River Basin
8 Santa Ana
9 San Diego
CALWATER WATERSHED
WATER BOD\' TYPE
B = Bays and ll11rllors
C= Coastal Shorelines/Beaches
E = Estuaries
L = Lakes/lteserviors
R = Rivers and St.-eams
S= Saline Lakes
T= Wellands, Tidal
W= Wetlands, Freshwater
"Calwater Watershed" Is the State Water Resources Control Board hydrological subunit area or an c,·cn smaller area dellneation.
GROUP A PESTICIDES OR CHEM A
alddn, dieldrin, chlordane, cndrin, he11tachlor, he11taclilor epoxide,
hexachlorocyclohexane (including lindane), cndosulfon, and toxa11hcnc
/'age 17 t1f 17
·-1
I I
----ATTACHMENT B -------------------
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APPENDIX A
STORM WATER STANDARDS QUESTIONNAIRE
I INSTRUCTIONS:
This questionnaire must be completed by the applicant in advance of submitting for a development application
(subdivision and land use planning approvals and construction permits). The results of the questionnaire determine
the level of storm water pollution prevention standards applied to a proposed development or redevelopment
project. Many aspects of project site design are dependent upon the storm water pollution protection standards
applied to a project.
Applicant responses to the questionnaire represent an initial assessment of the proposed project conditions and
impacts. City staff has responsibility for making the final assessment after submission of the development
application. A staff determination that the development application is subject to more stringent storm water
standards, than initially assessed by the applicant, will result in the return of the development application as
incomplete.
If applicants are unsure about the meaning of a question or need help in determining how to respond to one or
more of the questions, they are advised to seek assistance from Engineering Department Development Services
staff.
A separate completed and signed questionnaire must be submitted for each new development application
submission. Only one completed and signed questionnaire is required when multiple development applications for
the same project are submitted concurrently. In addition to this questionnaire, applicants for construction permits
must also complete, sign and submit a Construction Activity Storm Water Standards Questionnaire.
To address pollutants that may be generated from new development, the City requires that new development and
significant redevelopment priority projects incorporate Permanent Storm Water Best Management Practices
(BMPs) into the project design, which are described in Chapter 2 of the City's Storm Water Standards Manual This
questionnaire should be used to categorize new development and significant redevelopment projects as priority or
non-priority, to determine what level of storm water standards are required or if the project is exempt.
1. Is your project a significant redevelopment?
Definition:
Significant redevelopment is defined as the creation, addition or replacement of at least 5,000 square feet of
impervious surface on an already existing developed site.
Significant redevelopment includes, but is not limited to: the expansion of a building footprint; addition to or
replacement of a structure; structural development including an increase in gross floor area and/or exterior
construction remodeling; replacement of an impervious surface that is not part of a routine maintenance activity;
and land disturbing activities related with structural or impervious surfaces. Replacement of impervious surfaces
includes any activity that is not part of a routine maintenance activity where impervious material(s) are removed,
exposing underlying soil during construction.
Note: If the Significant Redevelopment results in an increase of less than fifty percent of the impervious surfaces of
a previously existing development, and the existing development was not subject to SUSMP requirements, the
numeric sizing criteria discussed in Table 3 of 2.3.3.4 applies only to the addition, and not to the entire
development.
2. If your project IS considered significant redevelopment, then please skip Section 1 and proceed with Section
2.
3. If your project IS NOT considered significant redevelopment, then please proceed to Section 1.
21 SWMP Rev 6/4/08
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SECTION 1
NEW DEVELOPMENT
PRIORITY PROJECT TYPE YES NO Does you project meet one or more of the following criteria:
1. Home subdivision of 100 units or more. v' Includes SFD, MFD, Condominium and Apartments
2. Residential development of 10 units or more. v' Includes SFD, MFD, Condominium and Apartments
3. Commercial and industrial development greater than 100. 000 square feet including parking areas.
Any development on private land that is not for heavy industrial or residential uses. Example: Hospitals, V Hotels, Recreational Facilities, Shopping Malls, etc.
4. Heavy Industrial/ Industry greater than 1 acre (NEED SIC CODES FOR PERMIT BUSINESS TYPES) v' SIC codes 5013, 5014, 5541, 7532-7534, and 7536-7539
5. Automotive repair shop. v SIC codes 5013, 5014, 5541, 7532-7534, and 7536-7539
6. A New Restaurant where the land area of development is 5,000 square feet or more including parking
areas. ✓ SIC code 5812
7. Hillside development
(1) greater than 5,000 square feet of impervious surface area and (2) development will grade on any y
natural slope that is 25% or greater
8. Environmentally Sensitive Area (ESA).
Impervious surface of 2,500 square feet or more located within, "directly adjacent"2 to (within 200 feet), v or "discharging directly to"3 receiving water within the ESA1
9. Parking lot.
Area of 5,000 square feet or more, or with 15 or more parking spaces, and potentially exposed to urban ✓ runoff
10. Retail Gasoline Outlets -serving more than 100 vehicles per day v Serving more than 100 vehicles per day and greater than 5,000 square feet
11. Streets. roads, driveways. highways. and freeways. v Project would create a new paved surface that is 5,000 square feet or greater.
12. Coastal Development Zone. ✓ Within 200 feet of the Pacific Ocean and (1) creates more than 2500 square feet of impermeable
surface or (2) increases impermeable surface on propertv bv more than 10%.
1 Environmentally Sensitive Areas include but are not limited to all Clean Water Act Section 303(d) impaired water bodies;
areas designated as Areas of Special Biological Significance by the State Water Resources Control Board (Water Quality
Control Plan for the San Diego Basin (1994) and amendments); water bodies designated with the RARE beneficial use by
the State Water Resources Control Board (Water Quality Control Plan for the San Diego Basin (1994) and amendments);
areas designated as preserves or their equivalent under the Multi Species Conservation Program within the Cities and Count
or San Diego; and any other equivalent environmentally sensitive areas which have been identified by the Copermittees.
2 "Directly adjacent" means situated within 200 feet of the environmentally sensitive area.
3 "Discharging directly to" means outflow from a drainage conveyance system that is composed entirely of flows from the
subject development or redevelopment site, and not commingled with flow from adjacent lands.
Section 1 Results:
If you answered YES to ANY of the questions above you have a PRIORITY project and PRIORITY project requirements DO
apply. A Storm Water Management Plan, prepared in accordance with City Storm Water Standards, must be submitted at
time of application. Please check the "MEETS PRIORITY REQUIREMENTS" box in Section 3.
If you answered NO to ALL of the questions above, then you are a NON-PRIORITY project and STANDARD requirements
apply. Please check the "DOES NOT MEET PRIORITY Requirements" box in Section 3.
SWMP Rev 6/4/08
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SECTION 2
SIGNIFICANT REDEVELOPMENT: YES NO
1. Is the project redeveloping an existing priority project type? (Priority projects ✓ are defined in Section 1)
If you answered YES, please proceed to question 2.
If you answered NO, then you ARE NOT a significant redevelopment and you ARE NOT subject to
PRIORITY project requirements, only STANDARD requirements. Please check the "DOES NOT MEET
PRIORITY Requirements" box in Section 3 below.
2. Is the project solely limited to one of the following:
a. Trenchinq and resurfacinq associated with utilitv work? '7
b. Resurfacinq and reconfiaurinq existina surface oarkina lots? v
C. New sidewalk construction, pedestrian ramps, or bike lane on public V and/or private existing roads?
d. Reolacement of existina damaaed oavement? v
If you answered NO to ALL of the questions, then proceed to Question 3.
If you answered YES to ONE OR MORE of the questions then you ARE NOT a significant redevelopment
and you ARE NOT subject to PRIORITY project requirements, only STANDARD requirements. Please
check
the "DOES NOT MEET PRIORITY Requirements" box in Section 3 below.
3. Will the development create, replace, or add at least 5,000 square feet of
impervious surfaces on an existing development or, be located within 200 ✓ feet of the Pacific Ocean and ( 1 )create more than 2500 square feet of
impermeable surface or (2) increases impermeable surface on property by
more than 10%?
If you answered YES, you ARE a significant redevelopment, and you ARE subject to PRIORITY project
requirements. Please check the "MEETS PRIORITY REQUIREMENTS" box in Section 3 below.
If you answered NO, you ARE NOT a significant redevelopment, and you ARE NOT subject to
PRIORITY project requirements, only STANDARD requirements. Please check the "DOES NOT MEET
PRIORITY Requirements" box in Section 3 below.
I SECTION 3
Questionnaire Results:
MY PROJECT MEETS PRIORITY REQUIREMENTS, MUST COMPLY WITH PRIORITY
PROJECT STANDARDS AND MUST PREPARE A STORM WATER MANAGEMENT PLAN FOR
SUBMITTAl AT TIME OF APPLICATION.
D
Address:
MY PROJECT DOES NOT MEET PRIORITY REQUIREMENTS AND MUST ONLY COMPLY
WITH STANDARD STORM WATER REQUIREMENTS.
Applicant Information and Signature Box This Box for City Use Only
Assessors Parcel Number( s ):
IL, ol~~ ~:" C.@::D CA. q~
City Concurrence: I YES I
I I
Applicant Title: By
Date:
ProJect ID:
NO
SWMP Rev 6/4/08
---ATTACHMENT C -------
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Efficient Irrigation SD-12
Design Objectives
0 Maximize Infiltration
0 Provide Retention
0 Slow Runoff
Minimize Impervious Land
Coverage
Prohibit Dumping of Improper
Materials
Description
Contain Pollutants
Collect and Convey
Irrigation water provided to landscaped areas may result in excess inigation water being
conveyed into stormwater drainage systems.
Approach
Project plan designs for development and redevelopment should include application methods of
irrigation water that minimize runoff of excess irrigation water into the stormwater conveyance
system.
Suitable Applications
Appropriate applications include residential, commercial and industrial areas planned for
development or redevelopment. (Detached residential single-family homes are typically
excluded from this requirement.)
Design Considerations
Designing New Installations
Toe follo,-ving methods to reduce excessive irrigation runoff should be considered, and
incorporated and implemented where determined applicable and feasible by the Pennittee:
■ Employ rain-triggered shutoff devices to prevent inigation after precipitation.
■ Design irrigation systems to each landscape area's specific water requirements.
■ Include design featuring flow reducers or shutoff valves
triggered by a pressure drop to control water loss in the event
of broken sprinkler heads or lines.
■ Implement landscape plans consistent ,-vitb County or City
water conservation resolutions, which may include provision
of water sensors, programmable irrigation times (for short
cycles), etc.
' 1~::A:,:f:;~., ,.~• ; ,;.~... ,.,,A~ 1
--.
ASQ
,.
January 2003 California Stormwater BMP Handbook
New De'lelopment and Redevelopment
www .cabmphancJbooks.com
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SD-12 Efficient Irrigation
■ Design timing and application methods of irrigation water to minimize the runoff of excess
irrigation water into the storm water drainage system.
■ Group plants with similar water requirements in order to reduce excess irrigation runoff and
promote smface filtration. Choose plants with lmv irrigation requirements (for example,
native or drought tolerant species). Consider design features such as:
Using mulches (such as wood chips or bar) in planter areas ,Aithout ground cover to
minimize sediment in runoff
Installing appropriate plant materials for the location, in accordance "ith amount of
sunlight and climate, and use native plant materials where possible and/or as
recommended by the landscape architect ·
Leaving a vegetative barrier along the property boundary and interior watercourses, to
act as a pollutant filter, where appropriate and feasible
Choosing plants that minimize or eliminate the use of fertilizer or pesticides to sustain
growth
■ Employ other comparable, equally effective methods to reduce ini.gation water runoff.
Redeveloping Existing Installations
Various jurisdictional storm water management and mitigation plans (SUSMP, WQMP, etc.)
define "redevelopment~ in terms of amounts of additional impervious area, increases in gross
floor area and/or exterior construction, and land disturbing activities with structural or
impervious surfaces. The definition of" redevelopment" must be consulted to determine
whether or not the requirements for new development apply to areas intended for
redevelopment. If the definition applies, the steps outlined under "designing ne·w installations"
above should be followed.
Other Resources
A Manual for the Standard Urban Stonmvater Mitigation Plan (SUSMP), Los Angeles County
Department of Public Works, May 2002.
Model Standard Urban Storm Water Mitigation Plan (SUSMP) for San Diego County, Port of
San Diego, and Cities in San Diego County, February 14, 2002.
Model Water Quality Management Plan (WQMP) for County of Orange, Orange County F1ood
Control District, and the Incorporated Cities of Orange County, Draft February 2003.
Ventura County\'\ide Technical Guidance Manual for Stormwater Quality Control Measures,
July 2002.
2 of 2 California Stormwater BMP Handbook
New Development and Redevelopment
www.cabmphandbooks.com
January 2003
Storm Drain Signage
Description
SD-13
Design Objectives
Maximize Infiltration
Provide Retention
Slow Runoff
Minimize Impervious Land
Coverage
0 Prohibit Dumping of Improper
Materials
Contain Pollutants
Collect and Convey
Waste materials dumped into storm drain inlets can have severe impacts on receiving and
gronnd waters. Posting notices regarding discharge prohibitions at storm drain inlets can
prevent waste dumping. Storm drain signs and stencils are highly visible source controls that
are typically placed directly adjacent to storm drain inlets.
Approach
The stencil or affixed sign contains a brief statement that prohibits dumping of improper
materials into the urban runoff conveyance system. Storm drain messages have become a
popular method of alerting the public about the effects of and the prohibitions against waste
disposal.
Suitable Applications
Stencils and signs alert the public to the destination of pollutants discharged to the stonn drain.
Signs are appropriate in residential, commercial, and industrial areas, as well as any other area
where contributions or dumping to stonn drains is likely.
Design Considerations
Storm drain message markers or placards are recommended at all storm drain inlets within the
boundary of a development project. The marker should be p_laced in clear sight facing toward
anyone approaching the inlet from either side. All storm drain inlet locations should be
identified on the development site map.
Designing New Installations
The following methods should be considered for inclusion in the
project design and show on project plans:
■ Pro\ide stenciling or labeling of all storm drain inlets and
catch basins, constructed or modified, within the project area
,\ith prohibitive language. Examples include "NO DU1\11PING
January 2003 California Stormwater BMP Handbook
New Development and Redevelopment
www .cabrnphandbooks.com
_.._. l._
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ASQ
1 of 2
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SD-13 Storm Drain Signage
-DRAINS TO OCEAN'' and/or other graphical icons to discourage illegal dumping.
■ Post signs ¼ith prohibitive language and/ or graphical icons, which prohibit illegal dumping
at public access points along channels and creeks within the project area.
Note -Some local agencies have approved specific signage and/or storm drain message placards
for use. Consult local agency stormwater staff to detennine specific requirements for placard
types and methods of application.
Redeveloping Existing Installations
Various jurisdictional stormwater management and mitigation plans (SUSMP, WQ1'IP, etc.)
define "redevelopment" in terms of amounts of additional impervious area, increases in gross
floor area and/or exterior construction, and land disturbing· activities ,-v:ith structural or
impervious surfaces. If the project meets the definition of"redevelopment", then the .
requirements stated under" designing new installations'" above should be included in all project
design plans.
Additional Information
Maintenance Considerations
■ Legibility of markers and signs should be maintained. If required by the agency ,vith
jurisdiction over the project, the owner/operator or homeowner's association should enter
into a maintenance agreement with the agency or record a deed restriction upon the
property title to maintain the legibility of placards or signs.
Placement
■ Signage on top of curbs tends to weather and fade.
■ Signage on face of curbs tends to be worn by contact ,-v:ith vehicle tires and sweeper brooms.
Supplemental Information
Examples
■ Most MS4 programs have storm drain signage programs. Some MS4 programs will provide
stencils, or arrange for volunteers to stencil storm drains as part of their outreach program.
Other Resources
A Manual for the Standard Urban Stormwater Mitigation Plan (SUSMP), Los Angeles County
Department of Public Works, May 2002.
Model Standard Urban Storm Water Mitigation Plan (SUSMP) for San Diego Comity, Po1t of
San Diego, and Cities in San Diego County, February 14, 2002.
Model Water Quality Management Plan (WQMP) for County of Orange, Orange County Flood
Control District, and the Incorporated Cities of Orange County, Draft February 2003.
Ventura Countyvvide Technical Guidance Manual for Stormwater Quality Control Measures,
.July 2002.
2 of 2 California Storrnwater BMP Handbook
New Development and Redevelopment
www .cabmphandbooks.com
January 2003
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Trash Storage Areas
Description
Trash storage areas are areas where a trash receptacle (s) are
located for use as a repository for solid wastes. Stormwater
runoff from areas where trash is stored or disposed of can be
polluted. In addition, loose trash and debris can be easily
transported by water or wind into nearby stonn drain inlets,
channels, and/or creeks. Waste handling operations that may be
sources of stonnwater pollution include dumpsters, litter control,
and waste piles.
Approach
This fact sheet contains details on the specific measures required
to prevent or reduce pollutants in stonnwater runoff associated
,v:itb trash storage and handling. Preventative measures
including enclosures, containment structures, and impervious
pavements to mitigate spills, should be used to reduce the
likelihood of contamination.
Suitable Applications
SD-32
Design Objectives
Maximize lnfiltrahon
Provide Reiention
Slow Runoff
Minimize Impervious Land
Coverage
Prohibit Dumping of Improper
Materials
0 Contain Pollutants
Collect and Convey
Appropriate applications include residential, commercial and industrial areas planned for
development or redevelopment. (Detached residential single-family homes are typically
excluded from this requirement.)
Design Considerations
Design requirements for waste handling areas are governed by Building and Fire Codes, and by
current local agency ordinances and zoning requirements. The design criteria described in this
fact sheet are meant to enhance and be consistent with these code and ordinance requirements.
Hazardous waste should be handled in accordance with legal requirements established in Title
22, California Code of Regulation.
Wastes from commercial and industrial sites are typically hauled by either public or commercial
carriers that may have design or access requirements for waste storage areas. 111e design
criteria in this fact sheet are recommendations and are not intended to be in conflict ,.,ith
requirements established by the waste hauler. The vvaste hauler should be contacted prior to the
design of your site trash collection areas. Conflicts or issues should be discussed vvith the local
agency.
Designing New Installations
Trash storage areas should be designed to consider the following structural or treatment control
BMPs:
■ Design trash container areas so that drainage from adjoining
roofs and pavement is diverted around the area(s) to avoid
run-on. This might include benning or grading the waste
handling area to prevent run-on of stormwater_
■ Make sure trash container areas are screened or walled to
prevent off-site transport of trash.
Januar1 2003 California Stormwater BMP Handbook
New Development and Redevelopment
www.cabmphandbooks.com
ASQ
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SD-32 Trash Storage Areas
■ Use lined bins or dumpsters to reduce leaking of liquid waste.
■ Provide roofs, av1-1lings, or attached lids on all trash containers to mininlize direct
precipitation and prevent rainfall from entering containers.
■ Pave trash storage areas with an impervious surface to mitigate spills.
■ Do not locate storm drains in immediate vicinity of the trash storage area.
■ Post signs on all dumpsters infornling users that hazardous materials are not to be disposed
of therein.
Redeveloping Existing Jpstallations
Various jurisdictional stormwater management and mitigation plans (SUSMP, WQMP, etc.)
define "redevelopment,. in terms of amounts of additional impervious area, increases in gross
floor area and/or exterior construction, and land disturbing activities with structural or
impervious surfaces. The definition of" redevelopment" must be consulted to deternline
whether or not the requirements for new development apply to areas intended for
redevelopment. If the definition applies, the steps outlined under "designing new installations"
above should be followed.
Additional Information
Maintenance Considerations
The integrity of structural elements that are subject to damage (i.e., screens, covers, and signs)
must be maintained by the owner/ operator. Maintenance agreements between the local agency
and the owner/ operator may be required. Some agencies will require maintenance deed
restrictions to be recorded of the property title. If required by the local agency, maintenance
agreements or deed restrictions must be e.xecuted by the owner/ operator before improvement
plans are approved.
Other Resources
A Manual for the Standard Urban Stormwater Mitigation Plan (SUSMP), Los Angeles County
Department of Public Works, May 2002.
Model Standard Urban Storm Water Mitigation Plan (SUSMP) for San Diego County, Port of
San Diego, and Cities in San Diego County, February 14, 2002.
Model Water Quality Managemenf Plan (WQMP) for County of Orange, Orange County Flood
Control District, and the Incorporated Cities of Orange County, Draft February 2003.
Ventura County"½ide Technical Guidance Manual for Storrnwater Quality Control Measures,
July 2002.
2 of 2 California Stormwater BMP Handbook
New Development and Redevelopment
www .cabmphandbooks.com
January 2003
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Extended Detention Basin
Description
Dry extended detention ponds (a.k.a. dry ponds, extended
detention basins, detention ponds, extended detention ponds)
are basins whose outlets have been designed to detain the
stormwater runoff from a water quality design storm for some
minimum time (e.g., 48 hours) to allow particles and associated
pollutants to settle. Unlike wet ponds, these facilities do not have
a large permanent pool. They can also be used to provide flood
control by including additional flood detention storage.
California Experience
Caltrans constructed and monitored 5 extended detention basins
in southern California with design drain times of 72 hours. Four
of the basins were earthen, less costly and had substantially
better load reduction because of infiltration that occurred, than
the concrete basin. The Caltrans study reaffirmed the flexibility
and performance of this conventional technology. The small
headloss and few siting constraints suggest that these devices are
one of the most applicable technologies for storm water
treatment.
Advantages
■ Due to the simplicity of design, extended detention basins are
relatively easy and inexpensive to construct and operate.
■ Extended detention basins can provide substantial capture of
sediment and the toxics fraction associated with particulates.
■ Widespread application with sufficient capture volume can
provide significant control of channel erosion and
enlargement caused by changes to flow frequency
January 2003
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New Development and Redevelopment
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TC-22
Design Considerations
■ Tributary Area
■ Area Required
■ Hydraulic Head
Targeted Constituents
0 Sediment A
0 Nutrients •
0 Trash ■
0 Metals A
0 Bacteria A
0 Oil and Grease A
0 Organics A
Legend (Removal Effectiveness)
• Low ■ High
A Medium
--..... ~
ASQ
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TC-22 Extended Detention Basin
relationships resulting from the increase of impervious cover in a watershed.
Limitations
■ Limitation of the diameter of the orifice may not allow use of extended detention in
watersheds ofless than 5 acres (would require an orifice with a diameter ofless than 0.5
inches that would be prone to clogging).
■ Dry extended detention ponds have only moderate pollutant removal when compared to
some other structural stormwater practices, and they are relatively ineffective at removing
soluble pollutants.
■ Although wet ponds can increase property values, dry ponds can actually detract from the
value of a home due to the adverse aesthetics of dry, bare areas ana inlet and outlet
structures.
Design and Sizing Guidelines
■ Capture volume determined by local requirements or sized to treat 85% of the annual runoff
volume.
■ Outlet designed to discharge the capture volume over a period of hours.
■ Length to width ratio of at least 1.5:1 where feasible.
■ Basin depths optimally range from 2 to 5 feet.
■ Include energy dissipation in the inlet design to reduce resuspension of accumulated
sediment.
-■ A maintenance ramp and perimeter access should be included in the design to facilitate
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access to the basin for maintenance activities and for vector surveillance and control.
■ Use a draw down time of 48 hours in most areas of California. Draw down times in excess of
48 hours may result in vector breeding, and should be used only after coordination with
local vector control authorities. Draw down times of less than 48 hours should be limited to
BMP drainage areas with coarse soils that readily settle and to watersheds where warming
may be determined to downstream fisheries.
Construction/Inspection Considerations
■ Inspect facility after first large to storm to determine whether the desired residence time has
been achieved.
■ When constructed with small tributary area, orifice sizing is critical and inspection should
verify that flow through additional openings such as bolt holes does not occur.
Performance
One objective of stormwater management practices can be to reduce the flood hazard associated
with large storm events by reducing the peak flow associated with these storms. Dry extended
detention basins can easily be designed for flood control, and this is actually the primary
purpose of most detention ponds.
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Extended Detention Basin TC-22
Dry extended detention basins provide moderate pollutant removal, provided that the
recommended design features are incorporated. Although they can be effective at removing
some pollutants through settling, they are less effective at removing soluble pollutants because
of the absence of a permanent pool. Several studies are available on the effectiveness of dry
extended detention ponds including one recently concluded by Caltrans (2002).
The load reduction is greater than the concentration reduction because of the substantial
infiltration that occurs. Although the infiltration of stormwater is clearly beneficial to surface
receiving waters, there is the potential for groundwater contamination. Previous research on the
effects of incidental infiltration on groundwater quality indicated that the risk of contamination
is minimal.
There were substantial differences in the amount of infiltration that were observed in the
earthen basins during the Caltrans study. On average, approximately 40 percent of the runoff
entering the unlined basins infiltrated and was not discharged. The percentage ranged from a
high of about 60 percent to a low of only about 8 percent for the different facilities. Climatic
conditions and local water table elevation are likely the principal causes of this difference. The
least infiltration occurred at a site located on the coast where humidity is higher and the basin
invert is within a few meters of sea level. Conversely, the most infiltration occurred at a facility
located well inland in Los Angeles County where the climate is much warmer and the humidity
is less, resulting in lower soil moisture content in the basin floor at the beginning of storms.
Vegetated detention basins appear to have greater pollutant removal than concrete basins. In
the Caltrans study, the concrete basin exported sediment and associated pollutants during a
number of storms. Export was not as common in the earthen basins, where the vegetation
appeared to help stabilize the retained sediment.
Siting Criteria
Dry extended detention ponds are among the most widely applicable stormwater management
practices and are especially useful in retrofit situations where their low hydraulic head
requirements allow them to be sited within the constraints of the existing storm drain system. In
addition, many communities have detention basins designed for flood control. It is possible to
modify these facilities to incorporate features that provide water quality treatment and/or
channel protection. Although dry extended detention ponds can be applied rather broadly,
designers need to ensure that they are feasible at the site in question. This section provides
basic guidelines for siting dry extended detention ponds.
In general, dry extended detention ponds should be used on sites with a minimum area of 5
acres. With this size catchment area, the orifice size can be on the order of 0.5 inches. On
smaller sites, it can be challenging to provide channel or water quality control because the
orifice diameter at the outlet needed to control relatively small storms becomes very small and
thus prone to clogging. In addition, it is generally more cost-effective to control larger drainage
areas due to the economies of scale.
Extended detention basins can be used v.ri.th almost all soils and geology, with minor design
adjustments for regions of rapidly percolating soils such as sand. In these areas, extended
detention ponds may need an impermeable liner to prevent ground water contamination.
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TC-22 Extended Detention Basin
The base of the e>..1:ended detention facility should not intersect the water table. A permanently
wet bottom may become a mosquito breeding ground. Research in Southwest Florida (Santana
et al., 1994) demonstrated that intermittently flooded systems, such as dry extended detention
ponds, produce more mosquitoes than other pond systems, particularly when the facilities
remained wet for more than 3 days following heavy rainfall.
A study in Prince George's County, Maryland, found that stormwater management practices can
increase stream temperatures (Galli, 1990). Overall, dry extended detention ponds increased
temperature by about 5°F. In cold water streams, dry ponds should be designed to detain
stormwater for a relatively short time (i.e., 24 hours) to minimize the amount of warming that
occurs in the basin.
Additional Design Guidelines
In order to enhance the effectiveness of extended detention basins, the dimensions of the basin
must be sized appropriately. Merely providing the required storage volume will not ensure
maximum constituent removal. By effectively configuring the basin, the designer will create a
long flow path, promote the establishment of low velocities, and avoid having stagnant areas of
the basin. To promote settling and to attain an appealing environment, the design of the basin
should consider the length to width ratio, cross-sectional areas, basin slopes and pond
configuration, and aesthetics (Young et al., 1996).
Energy dissipation structures should be included for the basin inlet to prevent resuspension of
accumulated sediment. The use of stilling basins for this purpose should be avoided because the
standing water provides a breeding area for mosquitoes.
Extended detention facilities should be sized to completely capture the water quality volume. A
micropool is often recommended for inclusion in the design and one is shown in the schematic
diagram. These small permanent pools greatly increase the potential for mosquito breeding and
complicate maintenance activities; consequently, they are not recommended for use in
California.
A large aspect ratio may improve the performance of detention basins; consequently, the outlets
should be placed to maximize the flowpath through the facility. The ratio of flm,vpath length to
width from the inlet to the outlet
should be at least 1.5:1 (L:W)
where feasible. Basin depths
optimally range from 2 to s feet.
J
The facility's drawdown time
should be regulated by an orifice
or weir. In general, the outflow
structure should have a trash
rack or other acceptable means
of preventing clogging at the
entrance to the outflow pipes.
The outlet design implemented
by Caltrans in the facilities
constructed in San Diego County
used an outlet riser with orifices Figure 1
Example of Extended Detention Outlet Structure
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Extended Detention Basin TC-22
sized to discharge the water quality volume, and the riser overflow height was set to the design
storm elevation. A stainless steel screen was placed around the outlet riser to ensure that the
orifices would not become clogged with debris. Sites either used a separate riser or broad crested
weir for overflow of runoff for the 25 and greater year storms. A picture of a typical outlet is
presented in Figure 1.
The outflow structure should be sized to allow for complete drawdown of the water quality
volume in 72 hours. No more than 50% of the water quality volume should drain from the
facility within the first 24 hours. The outflow structure can be fitted with a valve so that
discharge from the basin can be halted in case of an accidental spill in the watershed.
Summary of Design Recommendations
(1) Facility Sizing -The required water quality volume is determined by local regulations
or the basin should be sized to capture and treat 85% of the annual runoff volume.
See Section 5.5.1 of the handbook for a discussion of volume-based design.
(2)
Cs)
Basin Configuration -A high aspect ratio may improve the performance of detention
basins; consequently, the outlets should be placed to maximize the flowpath through
the facility. The ratio of flowpath length to width from the inlet to the outlet should
be at least 1.5:1 (L:W). The flowpath length is defined as the distance from the inlet
to the outlet as measured at the surface. The width is defined as the mean width of
the basin. Basin depths optimally range from 2 to s feet. The basin may include a
sediment forebay to provide the opportunity for larger particles to settle out.
A micropool should not be incorporated in the design because of vector concerns. For
online facilities, the principal and emergency spillways must be sized to provide 1.0
foot of freeboard during the 25-year event and to safely pass the flow from 100-year
storm.
Pond Side Slopes -Side slopes of the pond should be 3:1 (H:V) or flatter for grass
stabilized slopes. Slopes steeper than 3:1 (H:V) must be stabilized with an
appropriate slope stabilization practice.
Basin Lining -Basins must be constructed to prevent possible contamination of
groundwater below the facility.
Basin Inlet -Energy dissipation is required at the basin inlet to reduce resuspension
of accumulated sediment and to reduce the tendency for short-circuiting.
Outflow Structure -The facility's drawdown time should be regulated by a gate valve
or orifice plate. In general, the outflow structure should have a trash rack or other
acceptable means of preventing clogging at the entrance to the outflow pipes.
The outflow structure should be sized to allow for complete drawdown of the water
quality volume in 72 hours. No more than 50% of the water quality volume should
drain from the facility within the first 24 hours. The outflow structure should be
fitted with a valve so that discharge from the basin can be halted in case of an
accidental spill in the watershed. This same valve also can be used to regulate the
rate of discharge from the basin.
January 2003
Errata 5-06
California Stormwater BMP Handbook
New Development and Redevelopment
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(6)
(8)
The discharge through a control orifice is calculated from:
where: Q = discharge (ft3/s)
C = orifice coefficient
A = area of the orifice (ft2)
g = gravitational constant (32.2)
H = water surface elevation (ft)
Ho= orifice elevation (ft)
Recommended values for Care o.66 for thin materials and 0.80 when the material is
thicker than the orifice diameter. This equation can be implemented in spreadsheet
form with the pond stage/volume relationship to calculate drain time. To do this, use
the initial height of the water above the orifice for the water quality volume. Calculate
the discharge and assume that it remains constant for approximately 10 minutes.
Based on that discharge, estimate the total discharge during that interval and the
new elevation based on the stage volume relationship. Continue to iterate until H is
approximately equal to Ho. When using multiple orifices the discharge from each is
summed.
Splitter Box -When the pond is designed as an offline facility, a splitter structure is
used to isolate the water quality volume. The splitter box, or other flow diverting
approach, should be designed to convey the 25-year storm event while providing at
least 1.0 foot of freeboard along pond side slopes.
Erosion Protection at the Outfall -For online facilities, special consideration should
be given to the facility's outfall location. Flared pipe end sections that discharge at or
near the stream invert are preferred. The channel immediately below the pond
outfall should be modified to conform to natural dimensions, and lined with large
stone riprap placed over filter cloth. Energy dissipation may be required to reduce
flow velocities from the primary spillway to non-erosive velocities.
Safety Considerations -Safety is provided either by fencing of the facility or by
managing the contours of the pond to eliminate dropoffs and other hazards. Earthen
side slopes should not exceed 3:1 (H:V) and should terminate on a flat safety bench
area. Landscaping can be used to impede access to the facility. The primary spillway
opening must not permit access by small children. Outfall pipes above 48 inches in
diameter should be fenced.
Maintenance
Routine maintenance activity is often thought to consist mostly of sediment and trash and
debris removal; however, these activities often constitute only a small fraction of the
maintenance hours. During a recent study by Caltrans, 72 hours of maintenance was performed
annually, but only a little over 7 hours was spent on sediment and trash removal. The largest
recurring activity was vegetation management, routine mowing. The largest absolute number of
hours was associated with vector control because of mosquito breeding that occurred in the
stilling basins (example of standing water to be avoided) installed as energy dissipaters. In most
cases, basic housekeeping practices such as removal of debris accumulations and vegetation
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Errata 5-06
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Extended Detention Basin TC-22
management to ensure that the basin dewaters completely in 48-72 hours is sufficient to prevent
creating mosquito and other vector habitats.
Consequently, maintenance costs should be estimated based primarily on the mowing frequency
and the time required. Mowing should be done at least annually to avoid establishment of
woody vegetation, but may need to be performed much more frequently if aesthetics are an
important consideration.
Typical activities and frequencies include:
■ Schedule semiannual inspection for the beginning and end of the wet season for standing
water, slope stability, sediment accumulation, trash and debris, and presence of burrows.
■ Remove accumulated trash and debris in the basin and around the riser pipe during the
semiannual inspections. The frequency of this activity may be altered to meet specific site
conditions.
■ Trim vegetation at the beginning and end of the wet season and inspect monthly to prevent
establishment of woody vegetation and for aesthetic and vector reasons.
■ Remove accumulated sediment and re-grade about every IO years or when the accumulated
sediment volume exceeds IO percent of the basin volume. Inspect the basin each year for
accumulated sediment volume.
Cost
Construction Cost
The construction costs associated with extended detention basins vary considerably. One recent
study evaluated the cost of all pond systems (Brown and Schueler, 1997). Adjusting for
inflation, the cost of dry extended detention ponds can be estimated with the equation:
where: C = Construction, design, and permitting cost, and
V = Volume (ft3).
Using this equation, typical construction costs are:
$ 41,600 for a 1 acre-foot pond
$ 239,000 for a 10 acre-foot pond
$ 1,380,000 for a 100 acre-foot pond
Interestingly, these costs are generally slightly higher than the predicted cost of wet ponds
(according to Brown and Schueler, 1997) on a cost per total volume basis, which highlights the
difficulty of developing reasonably accurate construction estimates. In addition, a typical facility
constructed by Caltrans cost about $160,000 with a capture volume of only 0.3 ac-ft.
An economic concern associated with dry ponds is that they might detract slightly from the
value of adjacent properties. One study found that dry ponds can actually detract from the
January 2003
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California Stormwater BMP Handbook
New Development and Redevelopment
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TC-22 Extended Detention Basin
perceived value of homes adjacent to a dry pond by between 3 and 10 percent (Emmerling-
Dinovo, 1995).
Maintenance Cost
For ponds, the annual cost of routine maintenance is typically estimated at about 3 to 5 percent
of the construction cost (EPA website). Alternatively, a community can estimate the cost of the
maintenance activities outlined in the maintenance section. Table 1 presents the maintenance
costs estimated by Caltrans based on their experience with five basins located in southern
California. Again, it should be emphasized that the vast majority of hours are related to
vegetation management (mowing).
Table 1 Estimated Average Annual Maintenance Effort
Activity Labor Hours Equipment& Cost Material ($)
Inspections 4 7 183
Maintenance 49 126 2282
Vector Control 0 0 0
Administration 3 0 132
Materials 535 535
Total 56 $668 $3,132
References and Sources of Additional Information
Brown, W., and T. Schueler. 1997. The Economics of Storm water BMPs in the Mid-Atlantic
Region. Prepared for Chesapeake Research Consortium. Edgewater, MD. Center for Watershed
Protection. Ellicott City, MD.
Denver Urban Drainage and Flood Control District. 1992. Urban Storm Drainage Criteria
Manual-Volume 3: Best Management Practices. Denver, CO.
Emmerling-Dinovo, C. 1995. Stormwater Detention Basins and Residential Locational
Decisions. Water Resources Bulletin 31(3): 515-521
Galli, J. 1990. Thermal Impacts Associated with Urbanization and Stormwater Management
Best Management Practices. Metropolitan Washington Council of Governments. Prepared for
Maryland Department of the Environment, Baltimore, MD.
GKY, 1989, Outlet Hydraulics of Extended Detention Facilities for the Northern Virginia
Planning District Commission.
MacRae, C. 1996. Experience from Morphological Research on Canadian Streams: Is Control of
the Two-Year Frequency Runoff Event the Best Basis for Stream Channel Protection? In Effects
of Watershed Development and Management on Aquatic Ecosystems. American Society of
Civil Engineers. Edited by L. Roesner. Snowbird, UT. pp. 144-162.
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Maryland Dept of the Environment, 2000, Maryland Stormwater Design Manual: Volumes 1 &
2, prepared by MDE and Center for Watershed Protection.
http: //www.mde.state.md. us/ environment/wma/stormwatermanual /index.html
Metzger, M. E., D. F. Messer, C. L. Beitia, C. M. Myers, and V. L. Kramer. 2002. The Dark Side
Of Stormwater Runoff Management: Disease Vectors Associated With Structural BMPs.
Stormwater 3(2): 24-39.
Santana, F., J. Wood, R. Parsons, and S. Chamberlain. 1994. Control of Mosquito Breeding in
Permitted Stormwater Systems. Prepared for Southwest Florida Water Management District,
Brooksville, FL.
Schueler, T. 1997. Influence of Ground Water on Performance of Stormwater Ponds in Florida:
Watershed Protection Techniques 2(4):525-528.
Watershed Management Institute (WMI). 1997. Operation, Maintenance, and Management of
Stormwater Management Systems. Prepared for U.S. Environmental Protection Agency, Office
of Water. Washington, DC.
Young, G.K., et al., 1996, Evaluation and Management of Highway Runoff Water Quality,
Publication No. FHWA-PD-96-032, U.S. Department of Transportation, Federal Highway
Administration, Office of Environment and Planning.
Information Resources
Center for Watershed Protection (CWP), Environmental Quality Resources, and Loiederman
Associates. 1997. Maryland Stormwater Design Manual. Draft. Prepared for Maryland
Department of the Environment, Baltimore, MD.
Center for Watershed Protection (CWP). 1997. Stormwater BMP Design Supplement for Cold
Climates. Prepared for U.S. Environmental Protection Agency, Office of Wetlands, Oceans and
Watersheds. Washington, DC.
U.S. Environmental Protection Agency (USEPA). 1993. Guidance Specifying Management
Measures for Sources ofNonpoint Pollution in Coastal Waters. EPA-840-B-92-002. U.S.
Environmental Protection Agency, Office of Water, Washington, DC.
January 2003
Errata 5-06
California Stormwater BMP Handbook
New Development and Redevelopment
www.cabmphandbook.com
9 of 10
TC-22 Extended Detention Basin
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10 of 10 California Stormwater BMP Handbook
New Development and Redevelopment
www.cabmphandbooks.com
PLAN VIEW
PROFILE
January 2003
Errata 5-06