HomeMy WebLinkAboutCT 04-01; POINSETTIA RIDGE; STORM WATER MANAGEMENT PLAN; 2010-05-01ENGINEERING ^ '^^-^
and Land S u r v e y^js. (^^ 6' . Professional Civil Engineer _ ^ ^
SWMP 10-10
^^^^
AMENDMENT TO STORM WATER MANAGEMENT PLAN
for
Poinsettia Ridge, CT 04-01
Prepared for:
Warmington Residential California
3090 Pullman Street
Costa Mesa, CA 9262
714-434-4325
Proiect Site Address
S.E. Corner, Blacic Rail Road & Songbird Avenue, Carlsbad, CA 92009
Prepared by;
Michael L. Benesh, R.C.E. 37893
Dote:
May 20, 2010
JN 09-sd050
-I
404 SOUTH LIVE OAK PARK ROAD • FALLBROOK, CA 92028
PHONE: 7 60 73 1 -6 603 • FAX 7 50 89 7-2 1 65 • E-MAIL: MBENESH@MLBENGINEERING.COM
f
storm Wafer Managemenf Plan (SWMP)
Poinseff/a Ridge. CT 04-01
Engineering
Contents
SEaiON 1. INTRODUaiON 1
SECTION 1.01 INTRODUCTION 1
SECTION 2. VICINITY MAP ; 2
SEaiON 3. PROJEa 3
SECTION 3.01 DESCRIPTION 3
SECTION 3.02 TOPOGRAPHY AND LAND USE 3
SECTION 4. SITE MAP 4
SEaiON 5. IDENTIFICATION OF POLLUTANTS OF CONCERN S
SECTION 5.01 ANTICIPATED POLLUTANTS 5
SECTION 5.02 RECEIVING WATERS 7
5.02.1 Beneficial Uses 7
5.02.1(0 Beneficial Uses for Inland Surface Waters 9
5.02.1(11) Beneficial Uses for Groun(dwater 9
SECTION 5.03 303(D) STATUS 9
SECTION 5.04 PRIMARY AND SECONDARY POLLUTANTS OF CONCERN 9
SEaiON 6. CONDITIONS OF CONCERN 10
SECTION 6.01 EXISTING AND POST CONSTRUCTION DRAINAGE 10
SECTION 6.02 SOIL CHARACTERISTICS 11
SECTION 6.03 DOWNSTREAM CONDITIONS OF CONCERN 12
SECTION 7. UD SITE DESIGN BMPS 12
SECTION 7.01 MAINTAIN PRE-DEVELOPMENT RAINFAL RUNOFF CHARACTERISTICS 12
7.01.3 BIVIP-1 Minimize Impervious Areas 12
7.01.2 BMP-2 Conserve Natural Areas 13
7.01.3 BMP-3 Minimize Directly Connected Impervious Areas. 13
7.01.4 BMP-4 Maximize Canopy Interception 13
SECTION 7.02 PROTECT SLOPES AND CHANNELS 14
7.02.1 BMPS Convey Runoff Safely from the Tops of Slopes 14
7.02.2 BMP-6 Vegetate Slopes vi/ith Native of Drought Tolerant Vegetation 14
7.02.3 BMP-7Stabilize Permanent Channel Crossings 14
7.02.4 BMPS Energy Dissipators 14
7.02.5 BMP-9 Minimize disturbances to natural drainages 14
SECTION 8. SOURCE CONTROL BMPS 14
SECTION 8.01 OUTDOOR MATERIAL STORAGE AREAS 14
SECTION 8.02 TRASH STORAGE AREAS 15
SECTION 8.03 INTEGRATED PEST MANAGEMENT SYSTEMS 15
8.03.1 BMP-12 Reduce Pesticide Use 15
8.03.2 BMP-13 Educational Material 15
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SECTION 8.04 EFFICIENT IRRIGATION SYSTEMS AND LANDSCAPE DESIGN 16
8.04.3 BMP-14 Rain Shutoff Devices 16
8.04.2 BMP-15 Landscape and Irrigation Design 16
8.04.3 BMP 16 Flow Reducers or Shutoff Valves 36
SECTION 8.05 STORM WATER CONVEYANCE SYSTEM STENCILING AND SIGNAGE 16
8.05.3 BMP-17 Catch Basin Stenciling 16
SECTION 9. BMPS APPUCABLE TO INDIVIDUAL PRIORITY PROJECT CATEGORIES 16
SECTION 9.01 RESIDENTIAL DRIVEWAYS AND GUEST PARKING 17
9.03.3 BMP-20 Driveway Design 37
9.01.2 Uncovered Guest Parking 3 7
SECTION 10. TREATMENT CONTROL BMP'S 17
SECTION 11. STORM WATER BMP MAINTENANCE 17
SECTION 12. SUMMARY CONCLUSIONS 17
SECTION 13. CERTIFICATION 18
Attachment A - Site Plan A-1
Attachment B - Computation Sheet for Runoff Coefficients B-l
Attachment C - Drainage Study C-l
Attachment D - Storm Water Standards Questionnaire D-1
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Section 1. Introduction
Section 1.01 Introduction
This SWMP is an amendment to the original SWMP prepared for the construction of the
improvements for the Yamamoto Property Subdivision (CT 04-01), which were completed
in 2008. This project is being updated and resubmitted to the City of Carlsbad for the
purposes of constructing the homes on the 16 lots and complying with the current SUSMP
requirements.
The purpose of this SWMP is to address the water quality impacts from the proposed
improvements on the Poinsettia Ridge, formerly the Yamamoto Property Subdivision (CT
04-01). Best Management Practices (BMPs) will be utilized to provide a long-term solution
to water quality. This SWMP is also intended to ensure the effectiveness of the BMPs
through proper maintenance that is based on long-term fiscal planning.
"The requirement to implement storm water BMP requirements for development projects is
based on Section 402 (p) of the CleanWater Act. The Federal Clean Water Act
amendments of 1987 established a framework for regulating storm water discharges from
municipal, industrial, and construction activities underthe NPDES program. Underthe
Federal Clean Water Act, municipalities throughout the nation are
issued a Municipal NPDES Permit. The primary goal of the Municipal Permit is to stop
polluted discharges from entering the storm water conveyance system and local
receiving and coastal waters. In California, the State Water Resources Control Board
(SWRCB), through the nine Regional Boards, administers the NPDES storm water municipal
permitting program. Based on the San Diego Municipal Permit issued by the San Diego
Regional Board, the City is required to develop and implement permanent storm water
BMPs addressing pollution from new development projects.
The City of Carlsbad's Storm Water Management and Discharge Control Ordinance
(Carlsbad Municipal Code Chapter 15.12), requires that all new development and
redevelopment activities complywith the storm water pollution prevention requirements.
These storm water pollution prevention requirements, which are described in detail in
Section 2.3, "Permanent Storm Water Best Management practices Selection Procedure,"
are site specific and vary based on the project's potential impact on receiving water
quality."
By definition, detached residential projects of more than 10 units, of which the Poinsettia
Ridge project is one, are classified as "priority projects". See the City of Carlsbad's
Stormwater Standards Questionaire in Attachment D.
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Section 2. Vicinity Mop
Figure 2.1: Vicinity Mop
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Section 3. Project
Section 3.01 Description
The project is a five acre site located within the 16 lot Carlsbad Tract No. 04-01
Subdivision in the City of Carlsbad, California.
The site is bordered by Black Rail Road to the West, Songbird Avenue and CT 00-13 to
the North, CT 99-10 to the South and CT 92-3 to the East.
The site is adjacent to single family homes on South, East and North. The site is
adjacent to agricultural land to the West.
The proposed project will place 16 single family residences on the existing building
pads put in place as part of the grading plan for CT 04-01. Street and utility
improvements are existing as well. The amount of anticipated grading is
approximately 800 cubic yards for forms and footings as the pads will remain at their
existing grade.
Section 3.02 Topography and Land Use
The site is currently vacant with 16 graded pads. There are two paved streets on site
which were built to serve the project. Half of the pads of the subdivision front along
Thrasher Place and the other half of the pads front along Surf Crest Avenue. Storm
water runoff from the Lots fronting along Thrasher Place will either enter an existing
storm drain catch basin at the southerly end of Thrasher Place which takes the runoff
out to a catch basin on the easterly side of Black Rail Road, or will enter an existing
gunite ditch that runs along the southerly subdivision boundary and curb outlets onto
Black Rail Road.. From there, it continues southerly along Black Rail Road to a storm
drain inlet 400 feet southerly of the site. The storm drain system outlets to a natural
drainage area southwesterly of the intersection of Black Rail Road and Aviara
Parkway, approximately 1500 feet southwesterly of the project site.
The lots fronting Surf Crest Avenue will have their runoff drained to Surfcrest and carried
northerly to Songbird Avenue. The remainder of the slopes along the easterly
subdivision boundary drain to an existing gunite ditch along the easterly property line,
then northerly to Songbird Avenue. Once in Songbird Avenue, runoff continues
northerly and easterly, along Cabella Place, and Docena Road to a storm drain
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system in the Aviara development. This storm drain system outlets to a natural
drainage area approximately 1500 feet easterly of the project site.
Through a series of storm drain culverts and natural drainage areas the storm water
runoff from this site eventually reaches the Batiquitos Lagoon and the Pacific Ocean.
The construction of the homes on the project will not alter the existing drainage
pattern. There will be an increase in the impervious area due to the homes being
constructed.
Section 4. Site Mop
The Project site map is included in Attachment A at the back of this report.
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Section 5. Identification of Pollutants of Concern
Section 5.01 Anticipated Pollutants
Genera/ Pollutant Categones
Priority
Project
Categories Sediments Nutrients
Heavy
Metals
Organic
Compounds
Trash &
Debris
Oxygen
Demanding
Substances
Oil &
Grease
Bacteria &
Viruses Pesticides
Detached
Residential
Development
X X X X X X X
Attached
Residential
Develooment
X x X P(l) P(2) P X
Commercial
Development
>100,000 ft2
P(i) p(i) P(2) X P(5) X P(3) P(5)
Automotive
Repair Shops x X(4)(5) X X
Restaurants X X X X
Hillside
Development
>5,000 ft2
X x X X X X
Parking Lots
P(l) P(l) x X P(l) X P(l)
Streets,
Highways &
Freev^ays
X P(l) x X(4) X P(5) X
X = anticipated
P = potential
(1) A potential pollutant if landscaping exists on-site.
(2) A potential pollutant if the project inciudes uncovered parking areas.
(3) A potential pollutant if land use involves food or animal waste products.
(4) Including petroleum hydrocarbons.
(5) Including solvents.
The anticipated pollutants for a residential development like this, as identified in Table
1 above, are:
• Sediment: Sediments are soils or other surficial materials eroded and then
transported or deposited by the action of wind, water, ice, or gravity. Sediments
can increase turbidity, clog fish gills, reduce spawning habitat, lower young
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aquatic organisms survival rates, smother bottom dwelling organisms, and
suppress aquatic vegetation growth.
• Nutrients: Nutrients are inorganic substances, such as nitrogen and phosphorus.
They commonly exist in the form of mineral salts that are either dissolved or
suspended in water. Primary sources of nutrients in Urban Runoff are fertilizers
and eroded soils. Excessive discharge of nutrients to water bodies and streams
can cause excessive aquatic algae and plant growth. Such excessive
production, referred to as cultural eutrophication, may lead to excessive decay
of organic matter in the water body, loss of oxygen in the water, release of
toxins in sediment, and the eventual death of aquatic organisms.
• Trash & Debris: Trash (such as paper, plastic, polystyrene packing foam, and
aluminum materials) and biodegradable organic matter (such as leaves, grass
cuttings, and food waste) are general waste products on the landscape. The
presence of trash and debris may have a significant impact on the recreational
value of a water body and aquatic habitat. Excess organic matter can create a
high biochemical oxygen demand in a stream and thereby lower its water
quality. In addition, in areas where stagnant water exists, the presence of excess
organic matter can promote septic conditions resulting in the growth of
undesirable organisms and the release of odorous and hazardous compounds
such as hydrogen sulfide.
• Oxygen Demanding Substances: This category includes biodegradable organic
material as well as chemicals that react with dissolved oxygen in water to form
other compounds. Proteins, carbohydrates, and fats are examples of
biodegradable organic compounds. Compounds such as ammonia and
hydrogen sulfide are examples of oxygen-demanding compounds. The oxygen
demand of a substance can lead to depletion of dissolved oxygen in a water
body and possibly the development of septic conditions.
• Oil & Grease: Oil and grease are characterized as high-molecular weight
organic compounds. Primary sources of oil and grease are petroleum
hydrocarbon products, motor products from leaking vehicles, esters, oils, fats,
waxes, and high molecular-weight fatty acids. Introduction of these pollutants to
the water bodies are very possible due to the wide uses and applications of
some of these products in municipal, residential, commercial, industrial, and
construction areas. Elevated oil and grease content can decrease the aesthetic
value of the water body, as well as the water quality.
• Bacteria & Virus: Pathogens (bacteria and viruses) are ubiquitous
microorganisms that thrive under certain environmental conditions. Their
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proliferation is typically caused by the transport of animal or human fecal wastes
from the watershed. Water, containing excessive bacteria and viruses can alter
the aquatic habitat and create a harmful environment for humans and aquatic
life. Also, the decomposition of excess organic waste causes increased growth
of undesirable organisms in the water.
Pesticides: Pesticides (including herbicides) are chemical compounds
commonly used to control nuisance growth or prevalence of organisms.
Excessive or improper application of a pesticide may result in runoff containing
toxic levels of its active ingredient.
Section 5.02 Receiving Waters
Please check the wal tershed(s) forthe project.
San Juan Santa Margarita San Luis Rey X Carlsbad
San Dieguito Penasquitos San Diego Pueblo San Diego
Sweetwater Otay Tijuana
'lease provide the lydrologic sub-area and number(s)
Number Name
904.51 Batiquitos
5.02.1 Beneficial Uses
The beneficial uses for the hydrologic unit are included in Tables 3.1 and 3.2, below.
These tables have been extracted from the Water Quality Control Plan for the San
Diego Basin. The beneficial uses are defined as follows:
• MUN- Municipal and Domestic Supply: Includes uses of water for community,
military, or individual water supply systems including, but not limited to, drinking
water supply.
• AGR - Agricultural Supply: Includes uses of water for farming, horticulture, or
ranching including, but not limited to, irrigation, stock watering, or support of
vegetation for range grazing.
• IND- Industrial Services Supply: Includes uses of water for industrial activities that do
not depend primarily on water quality including, but not limited to, mining, cooling
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water supply, hydraulic conveyance, gravel washing, fire protection, or oil well re-
pressurization.
• BIOL - Preservation of Biological Habitats of Special Significance: Includes uses of
water that support designated areas or habitats.
• EST- Estuarine Habitat: Includes uses of water that support estuarine ecosystems,
including but not limited to preservation or enhancement of estuarine habitats,
vegetation, fish, shellfish, or wildlife.
• MAR- Marine Habitat: Includes uses of water that support marine ecosystems,
including but not limited to presen/ation or enhancement of marine habitats,
vegetation, fish, shellfish, or wildlife.
• MIGR- Migration of Aquatic Organisms: Includes uses of water that support habitats
necessary for migration, acclimatization between fresh and salt water, or other
temporary activities by aquatic organisms, such as anadromous fish.
RARE- Rare, threatened or endangered species: Includes uses of water necessary,
al least in part, for the survival and successful maintenance of plant or animal
species established under State or Federal Law as rare, threatened or endangered.
• RECl- Contact Recreation: Includes uses of water for recreational activities
involving body contact with water, where ingestion of water is reasonably possible.
These uses include, but are not limited to, swimming, wading, water-skiing, skin and
SCUBA diving, surfing, white water activities, fishing, or use of natural hot springs.
• REC2- Non-Contact Recreation: Includes the uses of water for recreational
involving proximity to water, but not normally involving body contact with water,
where ingestion of water is reasonably possible. These uses include, but ore not
limited to, picnicking, sunbathing, hiking, camping, boating, tide pool and marine
life study, hunting, sightseeing, or aesthetic enjoyment in conjunction with the
above activities.
• SPWN- Spawning, reproduction or early development: Includes uses of water that
support high quality aquatic habitats suitable for reproduction and early
development of fish.
• WILD- Wildlife Habitat: Includes uses of water that support terrestrial ecosystems
including, but not limited to, preservation and enhancement of terrestrial habitats,
vegetation, wildlife, (e.g., mammals, birds, reptiles, amphibians, invertebrates), or
wildlife water and food sources.
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5.02.1 (i) Beneficial Uses for Inland Surface Waters
The inland surface waters downstream of this project hove the following beneficial
uses as shown on Table 3.1
Table 3.1 - Beneficial Uses for Inland Surface Waters
Hydrologic Unit MUN AGR 1 _j
o
CQ
1—
t/i LU MAR MIGR RARE REC 1 REC 2 SPWN WILD 904.51
• Existing Beneficial Use
5.02.1 (il) Beneficial Uses for Groundwater
The ground water for this project has the following beneficial uses as shown in Table
3.2.
Table 3.2 - Beneficial Uses for Groundwater
Hydrologic Unit REC 2 MUN AGR Z
_i
0
CQ
1—
IU MAR MIGR RARE REC 1 REC 2 Z
Q.
(/) WILD 904.51 • • •
• Existing Beneficial Use
Section 5.03 303(d) Status
According to the California 2006 303(d) list published by the San Diego Regional Water
Quality Control Board, the water bodies that are associated with this project, i.e. the
Batiquitos Lagoon, are not impaired.
Section 5.04 Primary and Secondary Pollutants of Concern
As there ore no impaired waters downstream of the project, there ore no primary
pollutants of concern. Secondary pollutants of concern would be the anticipated
pollutants identified in Section 5.01.
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Section 6. Conditions of Concern
Section 6.01 Existing and Post Construction Drainage
The streets and grading and drainage improvements for the residences hove already
been constructed in the first phase of the project. This amendment odds the
construction of houses on the existing building pods, and will not alter drainage
patterns on the site or the surrounding area. The Storm water discharge points will not
divert runoff from existing conditions.
Approximately 0.9 acres of open ground will be covered by the single-family
residences and appurtenant driveways. This area plus the approximately 1.1 acres of
previously paved streets and sidewalks will moke a total of 2.0 acres of impervious
surfaces on the site. Thus, the impervious area on the site will increase from 0.31 acres
in the original undeveloped condition to 2.0 acres after completed development, or
from approximately 6% to 40% impervious area.
This change in land use will increase the composite runoff coefficient, of the project,
from C=0.38 to C=0.57. Also, the total peak 10 year storm flow rote will increase from
6.0 cfs under the undeveloped condition to 7.3 cfs under the proposed condition. A
detailed description of the drainage patterns and flows are discussed in the Drainage
Report submitted to the City of Corlsbad for this development. A copy of this report is
included in Attachment C to this report. See Table 4.1 and Attachment B for
Impervious area calculations.
Table 4.1 - Impervious Areas & Runoff Coefficients
Construction site area 5.0 acres
Percentage impervious area before construction 6 %
Runoff coefficient before construction n) 0.38
Percentage impervious area after construction 40 %
Runoff coefficient after construction (i) 0.57
Anticipated off-site storm water flow on to the
construction site 0 cfs
Calculations are shown in Attachment B
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The runoff from this site both in the existing state and the proposed development is
directed to two distinct outflows. Both outflows lead to natural drainage areas via
paved streets and storm drain systems. The existing natural environment sen/es as a
bio-filter for the runoff generated from the area.
Each residential lot will incorporate the following post construction BMP's to reduce
and treat the amount of storm runoff leaving the site:
• Vegetated Swales will be incorporated in to the yard drainage system for each
lot, treating the roof and yard runoff before it leaves each lot.
• A strip of pen/ious interlocking paving blocks shall be utilized at the downstream
end of the driveways for each lot where the driveway drains to the street to
reduce and break up the impervious area created by the subdivision and
increase infiltration.
Refer to the Site Map in Attachment A for post construction BMP locations.
Summaries of the post-construction water quality flows ore included in Table 4.2. The
flows were developed using a Precipitation of 0.2 inches per hour per the Son Diego
County SUSMP Manual Doted March 25, 2010. See Attachment C for excerpt.
Table 4.2 - Post Construction Water Quality Flows
Outfall Tributary Area
(Acres) Qio QwQ
A (East) 1.5 2.3 0.17
B (West) 2.7 4.0 0.31
C (South) 0.65 1.0 0.07
(1) Calculations ore shown in Attachment C
Section 6.02 Soil Ciiaracteristics
The project area consists of soil group D with a saturated infiltration rote of from 0.00 to
0. 05 in./hr. The project will not hove slopes steeper than 2:1. All slopes will include
slope protection such as berms or brow ditches at the tops of slopes, and landscaping
and irrigation to limit the potentiol for erosion. (Note: Information regarding soils group
infiltration rotes is from the County of Son Diego Guidelines for Determining
Significonce for Surface Water Quality. See Attachment B for excerpt.
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Section 6.03 Downstream Conditions of Concern
Downstream of the project site the storm water runoff will be conveyed either by a city
maintained storm drain system or a natural drainage channel until it reaches the
Batiquitos Lagoon. The outlets for the city storm drains ore adequately protected to
limit erosion and the natural drainage channels do not have signs of high amounts of
erosion or flooding. The natural drainage channels ore located on a golf course and
ore adequately maintained.
Section 7. LID Site Design BMPs
The City of Carlsbad Standard Urban Storm Water Mitigation Plan requires oil projects
subject to standard or priority project requirements to implement all applicable site
design BMPs listed below. Applicants may employ alternative comparable and
equally effective site design (including requirements applicable to individual priority
project categories), satisfactory to the City Engineer.
Projects ore encouraged to address these objectives through the creation of a
hydrologicolly functional project design that attempts to mimic the natural hydrologic
regime. Mimicking a site's natural hydrologic regime may be pursued by:
• Reducing imperviousness, consen/ing natural resources and areas, maintaining
and using natural drainage courses in the storm water conveyance system, and
minimizing clearing and grading that is necessary for the project.
• Providing runoff storage measures dispersed uniformly throughout a site's
landscape with the appropriate use of o variety of detention, retention, and
runoff practices.
• Implementing on-lot hydrologicolly functional landscape design and
management practices.
Section 7.01 Maintain Pre-Development rainfal runoff ciiaracteristics
Post-development peak storm water runoff discharge rates and velocities are controlled
to maintain or reduce pre-development development downstream erosion by applying
the following site design BMPs:
7.01.1 BMP-1 Minimize Impervious Areas
The project is designed to minimize the use of impervious areas in the following ways:
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• Streets areas hove been designed to meet the minimum City Standard widths of
36 feet from curb to curb.
• Sidewalks hove been constructed to minimum width allowed by the city.
• Building footprints hove been limited by the use of two story buildings on all but
two lots.
• Driveway widths hove been limited by the use of tandem parking in the
goroges.
• Portions of the driveways will be constructed with unit pavers.
7.01.2 BMP-2 Conserve Natural Areas
The site is on in-fill project surrounded by developed properties, and was previously
used for agricultural purposes. Therefore there ore no natural areas on the site to
conserve.
7.01.3 BMP-3 Minimize Directly Connected Impervious Areas
The project is designed to minimize directly connected impervious areas in the
following ways:
• The downhill end of oil the driveways that drain directly to the streets will be
constructed with unit pavers to disconnect the impervious areas. Drainage from
all other driveways will be directed into landscaped areas before entering
drainage systems.
• Rooftop drainage will be directed into the landscaped yard areas.
• Wolkwoys and patios will be drained to landscaped areas.
7.01.4 BMP-4 Maximize Canopy Interception
Canopy interception and water consen/ation will be maximized consistent with the
Corlsbad Landscape Manual in the following ways:
• The project landscape plans coll for the planting of over 40 trees in the street
right-of-way and the slope areas. The original site hod only one large eucalyptus
tree before grading.
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Section 7.02 Protect Slopes and Ctiannels
Slopes and channels ore protected on the site by implementing the following site
design BMPs:
7.02.1 BMP-5 Convey Runoff Safely from the Tops of Slopes
Drainage from all building pods is directed owoy from the tops of slopes and on earth
berm is installed at the tops of slopes to eliminote runoff over the slopes. Slopes along
the tract boundary ore protected by concrete brow ditches to convey drainage
safely to the bottom of the site.
7.02.2 BMP-6 Vegetate Slopes with Native of Drought Tolerant Vegetation
The landscape plans colls for vegetated the slopes with o mix of drought tolerant
ground covers, bushes and trees in compliance with the Carlsbad Landscape Manual.
7.02.3 BMP-7 Stabilize Permanent Channel Crossings
There are no permanent channel crossings located on the project site.
7.02.4 BMP-8 Energy Dissipators
All lined drainage ditches outlet to parkway culverts to eliminate the potential for
erosion. There ore no lined ditches or storm drains that outlet into unlined channels.
7.02.5 BMP-9 Minimize disturbances to natural drainages
There ore no natural drainages on the site. The site has been completely graded in the
post.
Section 8. Source Control BAAPs
Source control BMPs will consist of measures to prevent polluted runoff. The following
source control BMPs wholl be implemented on this site:
Section 8.01 Outdoor Material Storage Areas
This is a detached residential project and will not include any permanent outdoor
storage areas.
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Poinsettia Ridge, CT 04-01
Section 8.02 Trasti Storage Areas
This is a detached residential project and will not include ony control trosh storoge
areas. Individual homeowners will be required to use trash containers with attached
lids that exclude rain
Section 8.03 Integrated Pest Management Systems
Integrated pest management (IPM) is on ecosystem-based pollution prevention
strategy that focuses on long-term prevention of pests or their damage through a
combination of techniques such as biological control, habitat manipulation,
modification of cultural practices, and use of resistant plant varieties. Pesticides ore
used only after monitoring indicates they ore needed according to established
guidelines. Pest control materials ore selected and applied in o manner that minimizes
risks to human health, beneficial and non-torget organisms, and the environment.
The following source control BMP's shall be used on this project:
8.03.1 BMP-12 Reduce Pesticide Use
Common maintenance landscape areas will reduce the need for pesticide use in the
project design by:
• Planting pest resistont or well-adopted plant varieties such as native plants.
• Discourage pests by modifying the site and landscaping design.
8.03.2 BMP-13 Educational Material
This program will include an educational component directed at each homeowner.
The developer shall distribute IPM educational materials to future site residents/tenants.
Minimally, educational materials will address the following topics:
• Keeping pests out of buildings and landscaping using barriers, screens, and
caulking.
• Physical pest elimination techniques, such as weeding, squashing, trapping,
washing, or pruning out pests
• Relying on natural enemies to eat pests.
• Proper use of pesticides as o last line of defense.
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Engineering
Section 8.04 Efficient Irrigation Systems and Landscape Design
In compliance with the Water Consen/otion in Landscaping Act, the following source
control BMPs to reduce excessive irrigation runoff shall be implemented:
8.04.1 BMP-14 Rain Shutoff Devices
Commonly maintained londscoped areas shall employ rain shutoff devices to prevent
irrigation during and after precipitation.
8.04.2 BMP-15 Landscape and Irrigation Design
Commonly maintained landscaped areas shall have irrigation systems designed to
each landscope area's specific water requirements.
8.04.3 BMPl 6 Flow Reducers or Shutoff Valves
Commonly maintained landscaped areas shall use flow reducers or shutoff valves
triggered by o pressure drop to control water loss in the event of broken sprinkler
heads or lines.
Section 8.05 Storm Water Conveyance System Stenciling and Signage
The following source control BMPs to discourage illegal dumping shall be
implemented:
8.05.1 BMP-17 Catch Basin Stenciling
The developer will provide concrete stamping, porcelain tile, inset permanent marking
or equivalent as approved by the City of Carlsbad, for the on-site storm drain curb
inlet with prohibitive language (e.g., "No Dumping -1 Live Downstream"), satisfactory
to the City Engineer.
Section 9. BMPs Applicable to Individual Priority
Project Categories
All priority projects are required to incorporate site design BMPs applicable to the
category of the project as identified in Section 5, Table 1.
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Section 9.01 Residential Driveways and Guest Parking
This project is a detached residential development ond as such the following site
design BMPs shall be incorporoted into this priority project:
9.01.1 BMP-20 Driveway Design
Driveways shall either hove a three foot strip of interlocking pavers over on approved
sand or gravel base per the Soils Engineer's recommendations at their downhill end or
be designed to drain into adjacent landscaping.
9.01.2 Uncovered Guest Parl<ing
Guest parking spaces on privote property shall be designed to drain into adjacent
landscaping.
Section 10. Treatment Control BMP's
Priority projects are required to implement post construction structurol treatment
control BMPs to treat the project runoff for the primary pollutants of concern.
Alternatively, a project proponent may elect to implement o combination of LID BMPs
that either disperse and infiltrate, or direct to bioretention facilities, the flows from all
impervious areas on-site. These BMPs ore presumed to provide maximum extent
practicable treatment for all pollutants of concern; therefore no further
documentation of the treatment BMP selection process is required.
For this project all flows from on-site impervious areas ore being directed to
londscoped areas that disperse and infiltrate the storm water runoff.
Section 11. Storm Water BMP Maintenance
There ore no proposed permanent treatment control BMP's.
Section 12. Summary Conclusions
This SWMP has been prepared in accordance with the Watershed Protection, Storm
water Management, and Discharge Control Ordinance and the Storm water
Standards Manual. This SWMP hos evaluated and addressed the potential pollutants
associated with this project and their effects on water quality. A summary of the facts
and findings associated with this project ond the measures addressed by this SWMP is
OS follows:
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Engineering
• The beneficial uses for the receiving waters hove been identified. None of these
beneficial uses will be impaired or diminish due to the construction and operation
of this project.
• The project will not significantly alter patterns on the site. The discharge points will
not be chonged.
• Open areas and slopes will be landscaped to reduce or eliminate sediment
discharge.
• Interlocking concrete pavers will provide o disconnect between impervious
surfaces and reduce storm water runoff from the site.
• The combination of LID BMPs have the capacity to disperse and infiltrate the flows
from all impervious areas on-site. These BMPs are presumed to provide moximum
extent practicable treatment for all pollutants of concern; therefore no further
documentation of the treatment BMP selection process is required.
Section 13. Certification
This Storm Water Management Plan has been prepared under the direction of the
following Registered Civil Engineer. The Registered Civil Engineer attests to the
technical information contained herein and the engineering data upon which
recommendations, conclusions, and decisions are based.
Michael L. Benesh, KCb 3/«y3Va\ / *// Date
Exp.3/31/11
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Engineering
Attactiment A - Site Plan
See Mop in Folder.
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Engineering
Attactiment B - Computation Sheet for Runoff Coefficients
TOTAL SITE AREA 4.9 ACRES (A)
Existing Site Conditions
IMPERVIOUS AREA^ 0.3 ACRES (B)
IMPERVIOUSAREA RUNOFF COEFFICIENT^ 0.90 (C)
PERVIOUS AREA' 4.6 ACRES (D)
PERVIOUS AREA RUNOFF COEFFICIENT* 0.35 (E)
COMBINED RUNOFF COEFFICIENT 0.38 [BC+DE]/A
Proposed Site Conditions
IMPERVIOUS AREA^ 2.0 ACRES (F)
IMPERVIOUSAREA RUNOFF COEFFICIENT^ 0.90 (G)
PERVIOUS AREA' 2.9 ACRES (H)
PERVIOUS AREA RUNOFF COEFFICIENT" 0.35 (I)
COMBINED RUNOFF COEFFICIENT 0.57 [FG+HI]/A
Notes:
1. Includes paved areas, areas covered by buildings and other impervious areas.
2. 95% assumed.
3. Includes oreos of vegetation, unpaved soil areas, and other pervious areas.
4. Runoff Coefficient for rural areas per Appendix IX, Soil Type D, Son Diego Hydrology
Manual.
See County of Son Diego Guidelines for Detennining Significance of
Surface Water Quality Section 1.6- Infiltration and Runoff for Typical
Infiltration Rotes on following page.
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1.6 Infiltration and Runoff
Infiltration of water through soil can reduce the amount of water that reaches stormwater
management systems, filter pollutants and contaminants from the water, and recharge
the watershed. The USDA Natural Resources Conservation Service (NRCS; fomierly
the Soil Conservation Service [SCS]), classifies a soil's infiltration characteristics into
four Hydrologic Soil Groups (HSG):
Group A: Low runoff potential. Soils having high infiltration rates even when
thoroughly wetted and consisting chiefly of deep, well-drained sands or gravels.
Group B: Soils having moderate infiltration rates when thoroughly wetted and
consisting chiefly of moderately deep to deep, moderately well- to well-drained
sandy loam soils with moderately fine to moderately coarse textures.
Group C: Soils having slow infiltration rates when thoroughly wetted and
consisting chiefly of silty-loam soils with a layer that impedes downward
movement of water, or soils with moderately fine to fine texture.
Group D: High runoff potential. Soils having very slow infiltration rates when
thoroughly wetted and consisting chiefly of clay soils with a high swelling
potential, soils with a permanent high water table, soils with a claypan or clay
layer at or near the surface, and shallow soils over nearly impervious material.
Group A and B soils possess the greatest inflltration rates (unless soils are compacted
during construction) and are generally best suited to stormwater infiltration. However,
the San Diego Area has a relatively high concentration of Group 0 and D soils, which
possess lower infilti"ation rates that either limit the use of infiltration-based stormwater
management systems or require soil amendments to assist infiltration systems.
For a specific site, the HSG designation can be obtained by refenring to a local soil
survey, by consulting the complete national listing given in NRCS, or by performing an
on-site investigation. Soil Survey maps can be obtained from local NRCS offices or on-
line'* for use in estimating soil type. The NRCS maps are also available at the County of
San Diego, Department of Public Works. Consideration should be given to the effects of
urbanization on the natural hydrologic soil group. If heavy equipment can be expected
to compact the soil during construction or if grading will mix the surface and subsurface
soils, appropriate changes should be made in the soil group selected (SD County
Hydrology Manual 2003).
The table below presents soil infiltration rates for each soil group determined by
laboratory studies and measurements. Site designers should compare the design
runoff volume with the available soil storage volume to detennine if infiltration is
feasible, and then use the infiltration rates to determine if the design runoff volume can
infiltrate within a reasonable time (generally 24 to 48 hours). For sites with Group C and
^ http://websoilsurvev.nrcs.usda.aov/app/
Guidelines for Determining Significance
Surface Water Quality
D soils, retention- and detention based strategies are often more feasible than
inflltration designs.
TABLE 1
TYPICAL SOIL INFILTRATION RATES.
Minimum Infiltration Rate
Soil Type (inches per hour)
A 0.30 to 0.45
B 0.15 to 0.30
C 0.05 tc 0.15
D 0 to 0.05
In general, absorption of surface runoff by clay soils is low and reached quickly,
whereas in sandy soils a larger portion of the runoff infiltrates the land surface and
recharges the underlying groundwater system, resulting in less runoff.
1.7 Beneficial Uses of Water
Beneficial uses are defined as, "uses of water necessary for the survival or well being of
people, plants and wildlife." In San Diego County, residents, visitors and nature rely on
the region's water resources to provide beneficial uses such as ensuring a clean and
available drinking water supply, supporting agricultural, commercial, industrial,
recreational, residential, and military uses, and supporting wildlife and habitat. The
State Water Resources Control Board (SWRCB) has adopted a uniform list and
description of beneficial uses to be applied throughout all basins of the State
(Attachment B). These uses of water serve to promote the tangible and intangible
economic, social and environmental goals identified in the Water Quality Control Plan
forthe San Diego Basin (9) prepared by the RWQCB
(www.swrcb.ca-QOv/rwacb9/DroQrams/basinDlan.html).
1.8 Stormwater Drainage Svstems
Within urban areas stormwater and sewage systems run parallel but are not combined.
A vast amount of the unincorporated San Diego County is rural land that does not
support or require stormwater drainage facilities. In contrast, most urban areas within
unincorporated San Diego County have a range of stormwater drainage facilities, all of
which will continue to be improved as new discretionary projects are constructed.
Collectively, stormwater drainage facilities make up a stormwater conveyance system.
A stormwater conveyance system as defined by the County of San Diego Watershed
Protection, Stormwater Management, and Discharge Control Ordinance, "means private
and public drainage facilities other than sanitary sewers within the unincorporated areas
of San Diego County by which urban run-off may be conveyed to receiving waters, and
includes but is not limited to roads, sbreets, constructed channels, aqueducts, storm
drain, pipes, street gutters, inlets to storm drains or pipes, and catch basins."
Guidelines for Detennining Significance
Surface Water Quality
Engineering
Storm Water Pollution Prevention Plan (SWPPP)
Poinsettia Ridge, CT 04-01
Attactiment C - Drainage Study
Refer to Drainage Study for Poinsettia Ridge, CT 04-01 prepared by MLB Engineering.
Computations for Water Quality Flows: 0)
Ouffail Tributary Area
(Acres) IWQ(2) C(3) QwQ
A (East) 1.5 0.2 0.57 0.17
B (West) 2.7 0.2 0.57 0.31
C (South) 0.65 0.2 0.57 0.07
(1)
QWQ=CIWQA
QwQ=Water Quality Flow
C=Runoff Coeffecient
lwQ=Water Quality Rainfall Intensity
A=Area in Acres
(2) Rainfall Intensity value token from the Sizing Requirements for Stormwater
Treatment Facilities Section in Chapter 2 of the Son Diego County SUSMP Manual
doted March 25, 2010. See following page for excerpt.
(3) Calculations ore shown in Attachment B
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Page C-1
CHAPTER 2: CONCEPTS AND CRITERIA
• Design and construct pervious areas, if any, to effectiveljf receive and infiltrate runoff
from impervious areas, taking into account soil conditions, slope, and other pertinent
factors.
• Construct a portion of paved areas with low traffic and appropriate soil conditions
with permeable surfaces.
Tlie LID design procedure in Chapter 4 incorporates these requirements into an integrated
design which also meets sizing requirements for stormwater treatment facilities and flow-control
(hydromodification management) requirements.
• SIZING REQUIREMENTS FOR STORMWATER TREATMENT FACIUTIES
Tlie guidance in Chapter 4 was crafted to ensure LID fadlities comply with the NPDES permit's
hydraulic sizing requirements for stormwater treatment facilities and flow-control facilities. The
technical background follows.
Most runoff is produced by frequent storms of small or moderate intensitj' and duration.
Treatment facilities are designed to treat smaUer storms and the first flush of larger storms—
approximately 80% of average annual runoff
The NPDES permit identifies two types of treatment fadlities—^volume-based and flow-based.
VoluimMMiMd focllities must be designed to infiltrate, filter, or treat the volume of runoff
produced from a 24-hour 85* percentile storm event as determined from the Count}' of San
Diego's 85"' Percentile Precipitation Isopluvial Map. As shown on the map, rainfall depths var\'
from about 0.55" to 1.5.5".
For flow-based fadlities, the NPDES permit specifies the rational method be used to determine
flow. The rational method uses the equation
Q = CiA, where
Q = flow
C = weighted runoff factor between 0 and 1
i = rainfall intensitv
A = area
The permit identifies two altematives for calculating rainfall intensity:
1. the 85th percentile rainfall intensit}' times two, or
2. 0.2 inches per hour.
30 County SUSMP— 25 March 2010
CHAPTER 2: CONCEPTS AND CRITERIA
It is t\'pically found that both methods yield similar results. The 0.2 inches per hour nunfall
intensity should be used for sizing tlow-based treatment facilities vvithin the County's
jurisdiction.
The 0.2 inches per hour criterion is the basis for a consistent countywide sizing factor for
bioretention facilities when used for stormwater treatment only (i.e., not for flow control). The
factor is based on maintaining a minimum percolation rate of 5 inches per hour through the
engineered soil mix. ITie sizing factor is the ratio of the design intensitj- of rainfall on tributar)'
imperxdous surfaces (0.2 inches/hour) to thc design percolation rate in the facilit)- (5
inches/hour), or 0.04 (dimensionless).
• FLOW-CONTROL (HYDROMODIFICATION MANAGEMENT)
The NPDHS permit specifies for applicable projects:
... post-project runoff flow rates and durations shall not exceed pre-project runofT
flow rates and durations where the increased discharge flow rates and durations will
result in increased potential for erosion or other significant adverse impacts to
beneficial uses, attributable to clmnges in flow rates and durations.
Under current Interim Hydromodification Criteria, the requirement applies to projects
disturiiing 50 acres or more, and applicants may select among three options for compliance:
Use a continuous simulation model to compare pre-project and post-project runoff, use LID
facilities with sizing factors and design criteria developed by the Copermittees, or identify a
specified exemption. See Chapter One.
The technical background for the Interim Hydromodification C^iriteria is in the memorandum
"Development of Interim I lydromodificarion C'riteria" (October .30, 2007) and other technical
documents available on the Project Clean Water website.
Ilydromnditlcation management criteria:
1. Post-construction peak run-off tlovv rates and velocities from fhe project site shall be
maintained at levels that will not cause a significant increase in downstream erosion.
2. Measures to control flow rates and \'elocities shall not disrupt flows and flow patterns
that are necessar)^ to support downstream wetlands or riparian habitats. Di\'ersion of
run-off to regional facilities shall not be allowed to deprive immediate dcnvnstream
habitats of the necessar)- natural low flows levels experienced during the dr)- weather
season or over-bank flow events.
3. Hardening natural downstream areas to prevent erosion is prohibited, except where
pre-development conditions are shown, to the satisfaction of flic County, to be so
erosive that hardening would be required even in the absence of the proposed
development.
31 County SUSMP— 25 March 2010
UlR ll Water Pollution Prevention Plan (SWPPP)
WiMIMW Poinsettia Ridge, CT 04-01
Engineering
Attactiment D - Storm Water Standards Questionnaire
See the City of Carlsbad's Storm Water Standards Questionnaire on the following
pages.
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APPENDIX A
STORM WATER STANDARDS QUESTIONNAIRE
I INSTRUCTIONS:
Ttiis questionnaire must be completed by tlie applicant in advance of submitting for a development application
(subdivision and land use planning approvals and construction permits). The results of ttie 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 seel< 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 IVIanagement 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 footpnnt; addition to or
replacement of a structure; structural development including an increase in gross floor area and/or exterior
construction remodeling; replacement of an impen/ious surface that is not part of a routine maintenance activity;
and land disturbing activities related with structural or impervious surfaces. Replacement of impen/ious 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
SECTION 1
PRIORITY PROJECT TYPE
Does you project meet one or more of the foiiowing criteria: YES NO
1. Home subdivision of 100 units or more.
Includes SFD, MFD, Condominium and Apartments x
2. Residential develooment of 10 units or more.
Includes SFD, MFD, Condominium and Apartments X
3 Commercial and industrial develooment areater than 100.000 sauare feet indudina oarkina areas.
Any development on private land that is not for heavy industrial or residential uses. Example: Hospitals,
Hotels, Recreational Facilities, Shopping Malls, etc.
x
4. Heavv Industrial/ Industry areater than 1 acre (NEED SIC CODES FOR PERMIT BUSINESS TYPES)
SIC codes 5013, 5014, 5541, 7532-7534, and 7536-7539 X
5. Automotive repair shop.
sic codes 5013, 5014, 5541, 7532-7534, and 7536-7539
6. A New Restaurant where the land area of develooment is 5.000 sauare feet or more indudina oarkina
areas.
sic code 5812
X
7. Hillside develooment
(1) greater than 5,000 square feet of impervious surface area and (2) development grade on any
natural slope that is 25% or greater
X
8. Environmentallv Sensitive Area (ESA).
Impen/ious surface of 2,500 square feet or more located within, "directly adjacent" to {within 200 feet),
or "discharging directly to"^ receiving water within the ESA^
X
9. Parkina lot.
Area of 5,000 square feet or more, or with 15 or more parking spaces, and potentially exposed to urban
runoff
X
10. Retail Gasoline Outlets - servina more than 100 vehides oer dav
Serving more than 100 vehicles per day and greater than 5,000 square feet X
11. Streets, roads, drivewavs. hiahwavs. and freewavs.
Project would create a new paved surface that is 5,000 square feet or greater. X
12. Coastal Develooment 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 property by more than 10%.
X
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 presen/es or their equivalent under the Multi Species Consen/ation Program within the Cities and Count
of 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
SECTION 2
SIGNIFICANT REDEVELOPMENT YES NO
1. Is the project«cedeveloping arj
are defined in SeC
isting priority project type? (Priority projects
If you answered YES, please proceed to question 2.
If you answered NO, then you ARE NOT a significant redevelopment and you
PRIORITY project requirements, only STANDARD requirements. Please check the
PRIORITY Requirements" box in Section 3 below.
NOT subject to
OES NOT MEET
2. Is the project solely limited to one of the following:
a. Trenching and resurfacing associated with utility work?
b. Resurfacing and reconfiguring existing surface parking lots?
New sidewalk construction, pedestrian ramps, or bike lane on publi
and/or private existing roads?
d. Replacement of existing damaged pavement?
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 redevelopmeri
and you ARE NOT subject to PRIORITY project requirements, only STANDARD requirements. Plea
check
the "DOES NOT MEET PRIORITY Requirements" box In Section 3 below.
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 (l)create more than 2500 square feet of
impermeable surface or (2) increases impermeable surface on property by
morethan 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.
SECTION 3
Questionnaire Results:
g| 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.
• MY PROJECT DOES NOT MEET PRIORITY REQUIREMENTS AND MUST ONLY COMPLY
WITH STANDARD STORM WATER REQUIREMENTS.
Applicant Infomiation and Signature Box This Box for City Use Only
Address: Assessors Parcel Number(s):
SE Cor. of Black Rail & Songbird 215-041-30 thru 45
Applicant Name: Applicant Title:
Applicant Signature: Date:
City Concurrence:
By:
Project ID:
SWMP Rev 6/4/08