Ord 569ORDINANCE NO. 569
AN ORDINANCE OF THE CITY OF POWAY, CALIFORNIA,
AMENDING TITLE 16 OF THE POWAY MUNICIPAL CODE
FOR STANDARD URBAN STORM WATER MITIGATION PLAN
WHEREAS, the 1987 amendments to the Federal Clean Water Act, as
implemented by the United States Environmental Protection Agency regulations
adopted November 16, 1990, make necessary the adoption of plans and programs for
storm water management that meet specified criteria; and
WHEREAS, Section 402 (p) of the Clean Water Act (33 U.S.C. 1251 et seq.), as
amended by the Water Quality Act of 1987, requires that all large and medium-sized
incorporated municipalities must:
1. "effectively" prohibit non-storm water discharges into the storm water
conveyance system; and
2. reduce the discharge of pollutants from storm water conveyance systems
to waters of the United States to the maximum extent practicable ("MEP); and
WHEREAS, the State Water Resources Control Board (SWRCB) and the
Regional Water Quality Control Board (RWQCB) for the San Diego Region, have
determined that in order to protect the waters of the United States, all jurisdictions,
regardless of population, must comply with all the federal regulations; and
WHEREAS, on February 21, 2001, the Regional Water Quality Control Board for
the San Diego Region issued Order No. 2001-01, National Pollution and Discharge
System Elimination System Permit No. CAS0108758, regulating storm water discharges
by the City of Poway and other municipal copermittees; and
WHEREAS, in order to implement the federal regulatory requirements and
Regional Water Quality Control Board for the San Diego Region, Order Number 2001-
01 described as above, the City of Poway must develop and implement a program to
address urban pollution issues in development planning for public and private projects;
and
WHEREAS, this Ordinance has been duly processed with proper public notice;
and
WHEREAS, the City of Poway has conducted legally noticed public hearings and
has provided all interested parties an opportunity to be heard on the issues; and
WHEREAS, the City of Poway has carefully considered the following proposed
Standard Urban Storm Water Mitigation Plan Ordinance and finds that its adoption is
required by Order No. 2001-01; that said Ordinance is enacted pursuant to the City's
police power in accordance with California Constitution Article XI, Section 7; that said
Ordinance is consistent with the City of Poway's General Plan; that said Ordinance
Ordinance No. 569
Page 2
provides for the protection of water resources within the City of Poway and the
protection of health, safety, and general welfare of its citizens.
NOW, THEREFORE, THE CITY COUNCIL OF THE CITY OF POWAY DOES
ORDAIN AS FOLLOWS:
Section 1:
The proposed Ordinance revision is exempt from the requirements of the California
Environmental Quality Act (CEQA) pursuant to the CEQA Guidelines Section
21080(15), in that the adoption of development standards relating to the improvement of
water quality will have no environmental impacts, and are being undertaken by the City
of Poway to implement a rule or regulation imposed by a State agency, board or
commission.
Section 2:
Title 16 of the Poway Municipal Code is hereby amended by incorporating the following
Division VI, Standard Urban Storm water Mitigation Plan:
16.100.010 Title.
The ordinance codified in this chapter shall be known as the "Standard Urban
Storm Water Mitigation Plan (SUSMP) Ordinance of the City of Poway."
16.100.020
A.
Statutory authority.
The municipal storm water National Pollutant Discharge Elimination
System (NPDES) Permit (Order No. 2001-01, NPDES No. CAS0108758,
hereinafter referred to as "Municipal Permit") issued to San Diego County,
the Port of San Diego, and 18 cities by the San Diego Regional Water
Quality Control Board (Regional Board) on February 21, 2001, requires
the development and implementation of a program addressing urban
runoff pollution issues in development planning for public and private
projects. This division is adopted because adoption is mandated by the
Municipal Permit.
The requirement to implement a program for development planning is
based on Federal and State statutes including: Section 402 (p) of the
Clean Water Act, Section 6217 of the Coastal Zone Act Reauthorization
Amendments of 1990 ("CZARA"), and the California Water Code. The
Clean Water Act amendments of 1987 established a framework for
regulating urban runoff discharges from municipal, industrial, and
construction activities under the NPDES program. The Municipal Permit
requires the implementation of a Jurisdictional Urban Runoff Management
Program (JURMP).
16.100.030
A.
16.100.040
a.
O~inance No. 569
Page 3
Purpose.
The primary objectives of this division are to:
Ensure that discharges from municipal urban runoff conveyance
systems do not cause or contribute to a violation of water quality
standards;
2. Effectively prohibit non-storm water discharges in urban runoff; and
3. Reduce the discharge of pollutants from urban runoff conveyance
systems to the Maximum Extent Practicable (MEP statutory standard).
The regulations of this division were developed to address post-
construction urban runoff pollution from new development and
redevelopment applications that fall under "priority project" categories.
The goal of this division is to develop and implement practicable policies
to ensure, to the maximum extent practicable, that development does not
increase pollutant loads from a project site. This includes mitigation of
urban runoff based on the flow rates and velocities of historical rainfall
events. This goal may be achieved through site-specific controls and/or
drainage area-based or shared structural treatment controls.
Applicability of division.
The regulations set forth in this chapter shall apply to the development
plan approval process for discretionary development applications, and
prior to issuing development permits for ministerial projects.
To allow flexibility in meeting the design standards set forth in this division,
structural treatment control Best Management Practices (BMPs) may be
located on- or off-site, used singly or in combination, or shared by multiple
developments, provided certain conditions are met.
All new development and significant redevelopment projects that fall into
one of the following "priority project" categories are subject to the
requirements of this division, subject to the lawful prior-approval provisions
of the Municipal Permit. In the instance where a project feature, such as a
parking lot, falls into a priority project category, the entire project footprint
is subject to the requirements of this division. These categories are:
1. Residential development of 100 units or more
2. Residential development of 10 to 99 units
o
Commercial development where the land area for development is
greater than 100,000 square feet
Ordinance No. 569
Page 4
4. Automotive repair shops
5. Restaurants
6. Hillside development greater than 5,000 square feet
Projects discharging to receiving waters within Environmentally
Sensitive Areas
Parking Lots greater than 5,000 square feet, or with greater than 15
parking spaces and potentially exposed to urban runoff
Streets, roads, highways, and freeways which would create a new
paved sun'ace that is 5,000 square feet or greater.
16.100.050
Limited exclusion.
Trenching and resurfacing work associated with utility projects are not
considered priority projects. Parking lots, buildings and other structures associated with
utility projects are subject to the requirements of this division if one or more of the
criteria for the above categories are met.
Se~ions:
16.101.010
16.101.020
16.101.030
16.101.040
16.101.050
16.101.060
16.101.070
16.101.080
16.101.090
16.101.100
16.101.110
16.101.120
16.101.130
16.101.140
16.101.150
16.101.160
16.101.170
16.101.180
Chapter 16.101
DEFINITIONS
Attached residential development.
Automotive repair shop.
Commercial development.
Commercial development greater than 100,000 square feet.
Detached residential development.
Directly connected impervious area (DCIA).
Environmentally sensitive areas.
Hillside.
Hillside development greater than 5,000 square feet.
Infiltration.
Maximum extent practicable (MEP).
New development.
Parking lot.
Projects discharging to receiving waters within
sensitive areas.
Project footprint.
Receiving waters
Residential development.
Restaurant.
environmentally
16.101.190
16.101.200
16.101.210
16.101.220
16.101.230
16.101.240
16.101.250
Ordinance No. 569
Page 5
Significant redevelopment.
Site design BMP.
Source control BMP (both structural and non-structural).
Storm water best management practice (BMP).
Storm water conveyance system.
Streets, roads, highways, and freeways.
Treatment control (structural) BMP.
16.101.010
Attached residential development.
"Attached residential development" means any development that provides 10 or
more residential units that share an interior/exterior wall. This category includes, but is
not limited to: dormitories, condominiums and apartments.
16.101.020
Automotive repair shop.
"Automotive repair shop" means a facility that is categorized in any one of the
following Standard Industrial Classification (SIC) codes: 5013, 5014, 5541, 7532-7534,
or 7536-7539.
16.101.030
Commercial development.
"Commercial development" means any development on private land that is not
exclusively heavy industrial or residential uses. The category includes, but is not limited
to: mini-malls and other business complexes, shopping malls, hotels, office buildings,
public warehouses, hospitals, laboratories and other medical facilities, educational
institutions, recreational facilities, plant nurseries, car wash facilities, automotive
dealerships, commercial airfields, and other light industrial complexes.
16.101.040
Commercial development greater than 100,000 square feet.
"Commercial development greater than 100,000 square feet" means any
commercial development with a project footprint of at least 100,000 square feet.
16.101.050
Detached residential development.
"Detached residential development" means any development that provides 10 or
more freestanding residential units. This category includes, but is not limited to:
detached homes, such as single-family homes and detached condominiums.
16.101.060
Directly connected impervious area (DCIA).
"Directly connected impervious area (DCIA)" means the area covered by a
building, impermeable pavement, and/ or other impervious surfaces, which drains
directly into the storm drain without first flowing across permeable vegetated land area
(e.g., lawns).
Ordinance No. 569
Page 6
16.101.070
Environmentally sensitive areas.
"Environmentally sensitive areas" means areas that include, but are not limited
to, all Clean Water Act 303(d) impaired water bodies ("303[d] water bodies"); areas
designated as an "Area of Special Biological Significance" (ASBS) by the State Water
Resources Control Board (Water Quality Control Plan for the San Diego Basin (1994)
and amendments); water bodies designated as having a RARE beneficial use by the
State Water Resources Control Board (Water Quality Control Plan for the San Diego
Basin (1994) and amendments), or areas designated as preserves or their equivalent
under the Multiple Species Conservation Program (MSCP) within the Cities and County
of San Diego. The limits of Areas of Special Biological Significance are those defined in
the Water Quality Control Plan for the San Diego Basin (1994 and amendments).
Environmentally sensitive area is defined for the purposes of implementing SUSMP
requirements, and does not replace or supplement other environmental resource-based
terms, such as "Environmentally Sensitive Lands," employed by the City in their land
development review processes.
16.101.080 Hillside.
"Hillside" means lands that have a natural gradient of 25 percent (4 feet of
horizontal distance for every 1 foot of vertical distance) or greater and a minimum
elevation differential of 50 feet, or a natural gradient of 200 pement (1 foot of horizontal
distance for every 2 feet of vertical distance) or greater and a minimum elevation
differential of 10 feet.
16.101.090
Hillside development greater than 5,000 square feet.
"Hillside development greater than 5,000 square feet" means any development
that would create more than 5,000 square feet of impervious surfaces in hillsides with
known erosive soil conditions.
16.101.100
Infiltration.
"Infiltration" means the downward entry of water into the surface of the soil.
16.101.110
Maximum extent practicable (MEP).
"Maximum extent practicable (MEP)" means the technology-based standard
established by Congress in the Clean Water Act 402(p)(3)(B)(iii) that municipal
dischargers of urban runoff must meet, MEP generally emphasizes pollution prevention
and source control BMPs primarily (as the first line of defense) in combination with
treatment methods serving as a backup (additional lines of defense).
16.101.120
New development.
"New development" means land disturbing activities; structural development,
including construction or installation of a building or structure, the creation of impervious
surfaces; and land subdivision.
Ordinance No. 569
Page 7
16.101.130
Parking lot.
"Parking lot" means land area or facility for the temporary parking or storage of
motor vehicles used personally, or for business or commerce.
16.101.140
Projects discharging to receiving waters within environmentally
sensitive areas.
"Projects discharging to receiving waters within environmentally sensitive areas"
means all development and significant redevelopment that would create 2,500 square
feet of impervious surfaces or increase the area of imperviousness of a project site to
10 percent or more of its naturally occurring condition, and either discharge urban runoff
to a receiving water within an environmentally sensitive area (where any portion of the
project footprint is located within 200 feet of the environmentally sensitive area), or
discharge to a receiving water within an environmentally sensitive area without mixing
with flows from adjacent lands (where the project footprint is located more than 200 feet
from the environmentally sensitive area).
16.101.150
Project footprint.
"Project footprint" means the limits of all grading and ground disturbance,
including landscaping, associated with a project.
16.101.160
Receiving waters.
"Receiving waters" means surface bodies of water, which directly or indirectly
receive discharges from urban runoff conveyance systems, including naturally occurring
wetlands, streams (perennial, intermittent, and ephemeral (exhibiting bed, bank, and
ordinary high water mark)), creeks, rivers, reservoirs, lakes, lagoons, estuaries, harbors,
bays and the Pacific Ocean. The Director of Development Services shall determine the
definition for wetlands and the limits thereof for the purposes of this definition, provided
this definition is as protective as the Federal definition utilized by the United States
Army Corps of Engineers and the United States Environmental Protection Agency.
Constructed wetlands are not considered wetlands under this definition, unless the
wetlands were constructed as mitigation for habitat loss. Other constructed BMPs are
not considered receiving waters under this definition, unless the BMP was originally
constructed in receiving waters.
BMPs constructed in "receiving waters" may be used to satisfy SUSMP
requirements if but only if that use is approved by the Director of Development Services.
16.101.170
Residential development.
"Residential development" means any development on private land that provides
living accommodations for one or more persons. This category includes, but is not
limited to: single-family homes, multi-family homes, condominiums, and apartments.
Ordinance No. 569
Page 8
16.101.180
Restaurant.
"Restaurant" means a stand-alone facility that sells prepared foods and drinks for
consumption, including stationary lunch counters and refreshment stands selling
prepared foods and drinks for immediate consumption (SIC code 5812).
16.101.190
Significant redevelopment.
"Significant redevelopment" means development that would create or add at least
5,000 square feet of impervious surfaces on an already developed site. Significant
redevelopment includes, but is not limited to: the expansion of a building footprint;
addition to or replacement of a structure; 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. Significant redevelopment
does not include trenching and resurfacing associated with utility work; resurfacing and
reconfiguring surface parking lots; new sidewalk construction, pedestrian ramps, or bike
lane on existing roads; and replacement of damaged pavement.
16.101.200
Site design BMP.
"Site design BMP" means any project design feature that reduces the creation or
severity of potential pollutant sources or reduces the alteration of the project site's
natural flow regime. Redevelopment projects that are undertaken to remove pollutant
sources (such as existing surface parking lots and other impervious surfaces) or to
reduce the need for new roads and other impervious surfaces (as compared to
conventional or Iow-density new development) by incorporating higher densities and/or
mixed land uses into the project design, are also considered site design BMPs.
16.101.210
Source control BMP (both structural and non-structural).
"Source control BMP (both structural and non-structural)" means land use or site
planning practices, or structures that aim to prevent urban runoff pollution by reducing
the potential for contamination at the source of pollution. Source control BMPs
minimize the contact between pollutants and urban runoff. Examples include roof
structures over trash or material storage areas, and berms around fuel dispensing
areas.
16.101.220
Storm water Best Management Practice (BMP).
"Storm water Best Management Practice (BMP)" means any schedule of
activities, prohibitions of practices, general good house keeping practices, pollution
prevention and educational practices, maintenance procedures, structural treatment
BMPs, and other management practices to prevent or reduce to the maximum extent
practicable the discharge of pollutants directly or indirectly to receiving waters. Storm
water BMPs also include treatment requirements, operating procedures and practices to
control site runoff, spillage or leaks, sludge or waste disposal, or drainage from raw
Ordinance No. 569
Page 9
material storage. This SUSMP groups storm water BMPs into the following categories:
site design, source control, and treatment control (pollutant removal) BMPs.
16.101.230 Storm water conveyance system.
"Storm water conveyance system" means private and public drainage facilities by
which storm water may be conveyed to receiving waters, such as: natural drainages,
ditches, roads, streets, constructed channels, aqueducts, storm drains, pipes, street
gutters, or catch basins.
16.101.240
Streets, roads, highways, and freeways.
"Streets, roads, highways, and freeways" means any project that is not part of a
routine maintenance activity, and would create a new paved surface that is 5,000
square feet or greater used for the transportation of automobiles, trucks, motorcycles
and other vehicles. For the purposes of SUSMP requirements, streets, roads, highways
and freeways do not include trenching and resurfacing associated with utility work;
applying asphalt overlay to existing pavement; new sidewalk, pedestrian ramps, or bike
lane construction on existing roads; and replacement of damaged pavement.
16.101.250
Treatment control (structural) BMP.
"Treatment control (structural) BMP" means any engineered system designed
and constructed to remove pollutants from urban runoff. Pollutant removal is achieved
by simple gravity settling of particulate pollutants, filtration, biological uptake, media
adsorption or any other physical, biological, or chemical process.
Chapter 16.102
ADMINISTRATION
Sections:
16.102.010
16.102.020
16.102.030
16.102.040
Limitations.
Provisions for SUSMP requirements.
Implementation.
Site design storm water treatment credits.
16.102.010
Limitations.
Where requirements of this division conflict with established local codes,
(e.g., specific language of signage used on storm drain stenciling), the
City Council may continue the local practice and modify this division to be
consistent with the code, except to the extent that the standards in this
division are more stringent than those under local codes, such more
stringent standards shall apply.
16.102.020
A.
Co
Ordinance No. 569
Page 10
This division is based on the Municipal Permit as it was in force at the time
of adoption hereof. Litigation is pending which may invalidate all or part of
the Municipal Permit. Adoption of this division is not a waiver by the City
of its legal rights related to that action. This division may appropriately be
amended in accordance with orders issued in that litigation.
Provisions for SUSMP requirements.
The requirements of this division shall be incorporated into the project
design and shown on the plans prior to approval of discretionary permits.
For projects requiring only ministerial permits, the requirements of this
division shall be incorporated into the project design and shown on the
plans prior to the issuance of any ministerial permits.
City departments carrying out public projects that are not required to
obtain permits shall be responsible for ensuring the requirements of this
division are incorporated into the project design and shown on the plans
prior to bidding for construction contracts, or equivalent. For public
projects the requirements of this division must be incorporated into the
project design and shown on the plans before allowing the project to
commence.
16.102.030
A.
Implementation.
All priority projects shall implement one or a combination of storm water
BMPs, including, 1) site design BMPs, 2) source control BMPs and, 3)
structural treatment BMPs after the pollutants and conditions of concern
have been identified.
Bo
Storm water BMPs shall be considered and implemented where expressly
required by this division and if not so required where determined
applicable and feasible by the Director of Development Services. It is
recommended that the U.S. Environmental Protection Agency's
"Preliminary Data Summary of Urban Runoff Best Management Practices"
(August 1999, EPA-821-R-99-012) be used as a guide. The storm water
BMPs shall adhere to the requirements of this division, and shall be
correctly designed so as to remove pollutants to the maximum extent
practicable. A flow chart summarizing the storm water BMP selection
procedure is provided in Figure 1.
16.102.040
Site design storm water treatment credits.
Project proponents may develop and submit for public review and comment and
City Council approval a regional Model Site Design Storm Water Treatment Credits
program that allows reductions in the volume or flow of storm water that must be
captured or treated on a project in return for the inclusion of specified project design
features in the project. The Model Site Design Storm Water Treatment Credits program
Ordinance No. 569
Page 11
shall be deemed to be a part of this division following City Council approval. Any such
model program shall specify the conditions under which project proponents can be
credited for the use of site design features and Iow impact development techniques that
can reduce the volume of storm water runoff, preserve natural areas, and minimize the
pollutant loads generated and potentially discharged from the site. Any Site Design
Storm Water Treatment Credits program implemented shall be consistent and compliant
with this division and approved by the City Council.
oo
Ordinance No.
Page 12
-~,
0
569
Chapter 16.103
Ordinance No. 569
Page 13
IDENTIFICATION OF POLLUTANTS AND CONDITIONS OF CONCERNS
Sections:
16.103.010
16.103.020
16.103.030
16.103.040
16.103.050
Identifying pollutants and conditions of concern.
General categories of water pollution.
Identifying pollutants from the project area.
Identifying pollutants of concern.
Identifying conditions of concern.
16.103.010
Identifying pollutants and conditions of concern.
Priority project proponents shall use this guidance to identify pollutants
and conditions of concern, for which they need to mitigate or protect
against. Site design and source control BMPs are required based on
pollutants commonly associated with the proposed project type (see Table
2, "Standard Storm Water BMP Selection Matrix"). Treatment Control
BMPs are also required for the project's expected pollutants of concern
(see Table 3).
Bo
For private priority projects, the information shall be provided with the
project application prior to being deemed complete. For public priority
projects, the information by the City Engineer shall be provided prior to
bidding for construction contracts.
16.103.020
General categories of water pollution.
Ao
Sediments - 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 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.
Metals - Metals are raw material components in non-metal products such
as fuels, adhesives, paints, and other coatings. The primary sources of
metal pollution in storm water are typically commercially available metals
and metal products. Metals of concern include cadmium, chromium,
Ordinance No. 569
Page 14
copper, lead, mercury, and zinc. Lead and chromium have been used as
corrosion inhibitors in primer coatings and cooling tower systems. At Iow
concentrations naturally occurring in soil, metals are not toxic. However,
at higher concentrations, certain metals can be toxic to aquatic life.
Humans can be impacted from contaminated groundwater resources and
bioaccumulation of metals in fish and shellfish. Environmental concerns,
regarding the potential for release of metals to the environment, have
already led to restricted metal usage in certain applications.
Compounds - Organic compounds are carbon-based. Commercially
available or naturally occurring organic compounds are found in
pesticides, solvents, and hydrocarbons. Organic compounds can, at
certain concentrations, indirectly or directly constitute a hazard to life or
health. When rinsing off objects, toxic levels of solvents and cleaning
compounds can be discharged to storm drains. Dirt, grease, and grime
retained in the cleaning fluid or rinse water may also adsorb levels of
organic compounds that are harmful or hazardous to aquatic life.
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 & 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. Also, 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 sulfides.
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 and Grease - Oil and grease are characterized as high-molecular
weight organic compounds. Primary soumes 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.
Ordinance No. 569
Page 15
Bacteria and Viruses - Bacteria and viruses are ubiquitous
microorganisms that thrive under certain environmental conditions. Their
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 application of a pesticide may result in runoff containing toxic
levels of its active component.
Ordinance No. 569
Page 16
16.103.030
Identifying pollutants from the project area.
Using Table 1, pollutants shall be identified that are anticipated to be generated
from the proposed priority project categories. Pollutants associated with any hazardous
material sites that have been remediated or are not threatened by the proposed project
are not considered a pollutant of concern.
Table 1, Antici ~nd Potential Pollutants Generated by Land Use Type.
i
, ~ General Pollutant Categories
lriority Trash Oxygen Bacteria
~roject Heavy Organic & Demanding Oil & &
~ategories Sediments Nutrients Metals Compounds Debris SubstancesGrease VirusesPesticides
letached esidential X X X X X X X
evelopment
lttached pC) p(~)
esidential X X X P X
evelopment
0 mmercial
velopment
o,ooo ~
lutomotive epair Shops X X(4x5) X X
~estaurants X X X X
5 IIIside
evelopment X X X X X X
,ooo ~
arking Lots
treets,
ighways & X Pc) X X(4) X P(5) X
reeways
= anticipated
= potential
) A potential pollutant if landscaping exists on-site.
) A potential pollutant if the project includes uncovered parking areas.
) A potential pollutant if land use involves food or animal waste products.
) Including petroleum hydrocarbons.
) Including solvents.
16.103.040
A.
Ordinance No. 569
Page 17
Identifying pollutants of concern.
Pollutants generated by the proposed priority project that exhibit one or
more of the following characteristics are considered primary pollutants of
concern:
1. Current loadings or historical deposits of the pollutant are impairing the
beneficial uses of a receiving water;
Elevated levels of the pollutant are found in water or sediments of a
receiving water and/or have the potential to be toxic to or
bioaccumulate in organisms therein; and
3. Inputs of the pollutant are at a level high enough to be considered
potentially toxic.
To identify primary pollutants of concern in receiving waters, each priority
project shall, at a minimum, do the following:
For each of the proposed projects discharge points, identify the
receiving water(s) that each discharge point proposes to discharge to,
including hydrologic unit basin number(s), as identified in the most
recent version of the Water Quality Control Plan for the San Diego
Basin, prepared by the San Diego Regional Water Quality Control
Board.
o
Identify any receiving waters, into which the developed area would
discharge to, listed on the most recent list of Clean Water Act Section
303(d) impaired water bodies. List any and all pollutants for which the
receiving waters are impaired.
o
Compare the list of pollutants for which the receiving waters are
impaired with the pollutants anticipated to be generated by the project
(as identified in Table 1). Any pollutants identified by Table 1 which
are also causing impairment of receiving waters shall be considered
primary pollutants of concern.
For projects where no primary pollutants of concern exist, those pollutants
identified through the use of Table 1 shall be considered secondary pollutants of
concern.
16.103.050
Identifying conditions of concern.
Common impacts to the hydrologic regime resulting from development typically
include increased runoff volume and velocity; reduced infiltration; increased flow
frequency, duration, and peaks; faster time to reach peak flow; and water quality
degradation. These changes have the potential to permanently impact downstream
Ordinance No. 569
Page 18
channels and habitat integrity. A change to a priority project site's hydrologic regime
would be considered a condition of concern if the change would impact downstream
channels and habitat integrity. Because of these potential impacts, the following steps
shall be followed by each priority project:
Evaluate the project's conditions of concern in a drainage study report
prepared by a registered civil engineer in the State of California, with
experience in fluvial geomorphology and water resources management.
The report shall consider the project area's location (from the larger
watershed perspective), topography, soil and vegetation conditions,
percent impervious area, natural and infrastructure drainage features, and
any other relevant hydrologic and environmental factors to be protected
specific to the project area's watershed.
Co
As part of the drainage study, the civil engineer shall conduct a field
reconnaissance to observe and report on downstream conditions,
including undercutting erosion, slope stability, vegetative stress (due to
flooding, erosion, water quality degradation, or loss of water supplies) and
the area's susceptibility to erosion or habitat alteration as a result of an
altered flow regime.
The drainage study shall compute rainfall runoff characteristics from the
project area including, at a minimum, peak flow rate, flow velocity, runoff
volume, time of concentration, and retention volume. These characteristics
shall be developed for the two-year and 10-year frequency, Type I storm,
of six-hour or 24-hour duration (whichever is the closer approximation of
the site's time of concentration), during critical hydrologic conditions for
soil and vegetative cover. The drainage study shall report the project's
conditions of concern based on the hydrologic and downstream conditions
discussed above. Where downstream conditions of concern have been
identified, the drainage study shall establish that pre-project hydrologic
conditions affecting downstream conditions of concern would be
maintained by the proposed project, satisfactory to the Director of
Development Services, by incorporating the site design, source control,
and treatment control requirements identified in this division.
Sections:
16.104.010
16.104.020
16.104.030
16.104.040
16.104.050
16.104.060
Chapter 16.104
ESTABLISHMENT OF STORM WATER BMPS
Progression of storm water BMPs.
Requirements to implement storm water BMPs.
Selection of storm water BMPs.
Storm water BMPs for projects not generating pollutants.
Storm water BMPs for projects generating primary and secondary
pollutants.
Alternative storm water BMPs.
Ordinance No. 569
Page 19
16.104.010
Progression of storm water BMPs.
Site design BMPs reduce the need for source and/or treatment control BMPs,
and source control BMPs may reduce the amount of treatment control BMPs needed.
Throughout all the following sections, all priority projects shall consider and incorporate
and implement where expressly required by this division, and if not so required where
determined applicable and feasible by the Director of Development Services, storm
water BMPs into the project design, in the following progression:
A. Site Design BMPs
B. Source Control BMPs
C. Treatment Control BMPs
16.104.020
Requirements to implement storm water BMPs.
As a minimum, priority projects must implement source control BMPs, and must
implement treatment control BMPs unless a waiver is granted based on the infeasibility
of all treatment control BMPs. BMPs must also achieve certain performance standards
set out in the Municipal Permit section F.2.(b) (i to xiv). Selection of BMPs from the
menus included in this division, using the rules set out in this division, must fulfill these
requirements. In addition, runoff treated by site design or source control BMPs, such as
rooftop runoff treated in landscaping, may be useful in reducing the quantity of runoff
required to be treated in "Treatment Control BMPs."
16.104.030
Selection of sto[m water BMPs.
Using the Treatment Control BMP Selection Matrix, each priority project shall
select a structural treatment BMP by comparing the list of pollutants for which the
downstream receiving waters are impaired (if any), with the pollutants anticipated to be
generated by the project (as identified in Table 1). Any pollutants identified by Table 1
which are also causing a Clean Water Act Section 303(d) impai[ment of the receiving
waters of the project shall be considered primary pollutants of concern. Priority projects
that are anticipated to generate a primary pollutant of concern shall meet all applicable
requirements of establishing storm water BMPs, and shall select a single or combination
of storm water BMPs from Table 3 which maximizes pollutant removal for the particular
primary pollutant(s) of concern.
16.104.040
Storm water BMPs for projects not generating pollutants.
Priority projects that are not anticipated to generate a pollutant for which the
receiving water is Clean Water Act Section 303(d) impaired shall meet applicable
standard requirements of establishing storm water BMPs, and shall select a single or
combination of storm water BMPs from Table 3 which are effective for pollutant removal
of the identified secondary pollutants of concern, consistent with the "maximum extent
practicable" standard defined in Attachment D of the Municipal Permit.
Ordinance No. 569
Page 20
16.104.050
Storm water BMPs for projects generating primary and secondary
pollutants.
Where a site generates both primary and secondary pollutants of concern,
primary pollutants of concern receive priority for BMP selection. For such
sites, selected BMPs must only maximize pollutant removal for the primary
pollutants of concern.
Where a site generates only secondary pollutants of concern, selected
BMPs shall target the secondary pollutant of concern determined to be
most significant for the project.
C°
Selected BMPs must be effective for the widest range of pollutants of
concern anticipated to be generated by a priority project (as identified in
Table 1), consistent with the maximum extent practicable standard defined
in Attachment D of the Municipal Permit.
16.104.060
Alternative storm water BMPs.
^ltemative storm water BMPs not identified in Table 3 may be approved at the
discretion of the Director of Development Services, provided the alternative BMP is as
effective in removal of pollutants of concern as other feasible BMPs listed in Table 3.
Ordinance No. 569
Page 21
Table 2, Site Design and Source Control Storm Water BMP Selection Matrix.
Source
Pdority Project Site Design Control
Category BMPs(~J BMPs~2) Requirements Applicable to Individual Pdodi ~/ Project Categories~3)
.= '~ ~ .~ z ~ '~ ~ ~ '~
~ °
~ ~o ~ ~ o ~ ~ ~ ~ =
Det~ohed
Residential R R R R R
Development
A~ohed
Residential R R R
Development
~mmercial
Development R R R R R R
>100,000 ~
Automotive
R R R R R R R
Repair Shop
Restaumn~ R R R R
Hillside
Development R R R R
>5,000 ~
Parking Lots R R R(4)
Streets,
Highways & R R R
Freeways
R = Required; select BMPs as r~uired from ~e applicable steps in Chapter 16.105 or Chapter 16.106.
(1) Refer to Chapter 16.105.
(2) Refer to Chapter 16.106.
(3) PHoH~ project categories must apply spec~c sto~ water BMP requirements, where appli~ble. Pmje~s are
subject to the requimmen~ of all pHoH~ pmje~ ~t~oHes that apply.
(4) Applies if the paved ama to~ls >5,000 square feet or with >15 pa~ing spaces and is potentially exposed to
urban runoff.
Table 3. Treatment Control BMP Selection Matrix.
Ordinance No. 569
Page 22
Pollutant of Treatment Control BMP Categories
Concern
Biofilters Detention Infiltration' w'et P'°nds Drainage Filtration Hydrodynamic
Basins Basins(i) or Wetlands Inserts Separator
Systems(2)
Sediment M H H H L H M
Nutrients L M M M L M L
Heavy Metals M M M H L H L
Organic U U U U L M L
Compounds
Trash & Debris L H U U M H M
Oxygen
Demanding L M M M L M L
Substances
Bacteria U U H U L M L
Oil & Grease M M U U L H L
Pesticides U U U U L U L
(1) Including trenches and porous pavement.
(2) Also known as hydrodynamic devices and baffle boxes.
L: Low removal efficiency
M: Medium removal efficiency
H: High removal efficiency
U: Unknown removal efficiency
Sources: Guidance Specifying Management Measures for Sources of Nonpoint Pollution in Coastal Waters (1993),
National Storm water Best Management Practices Database (2001), and Guide for BMP Selection in Urban
Developed Areas (2001).
Sections:
16.105.010
16.105.020
16.105.030
Chapter 16.105
SITE DESIGN BMPS
O~inance No. 569
Page 23
Site design BMPs objectives.
Maintaining pre-development rainfall runoff characteristics.
Protection of slopes and channels.
16.105.010
A.
16.105,020
A.
Site design BMPs objectives.
Priority projects shall be designed so as to minimize, to the maximum
extent practicable, the introduction of pollutants and conditions of concern
that may result in significant impacts generated from site runoff to the
storm water conveyance system. Priority projects shall also control post-
development peak storm water runoff discharge rates and velocities to
maintain or reduce pre-development downstream erosion and to protect
stream habitat. Although not mandatory, priority projects can address
these objectives through the creation of a hydrologically functional project
design that attempts to mimic the natural hydrologic regime. Mimicking a
site's natural hydrologic regime can be pursued by:
1. Reducing imperviousness, conserving natural resources and areas,
maintaining and using natural drainage courses in the storm water
conve,yance system, and minimizing clearing and grading.
2. Providing runoff storage measures dispersed unifo[mly throughout a
site's landscape with the use of a variety of detention, retention, and
runoff practices.
3. Implementing on-lot hydrologically functional landscape design and
management practices.
Site design BMPs shall offer an innovative approach to urban storm water
management that does not rely on the conventional end-of-pipe or in-the-
pipe structural methods but instead uniformly or strategically integrates
storm water controls throughout the urban landscape.
Maintaining pre-development rainfall runoff characteristics.
Priority projects shall control post-development peak storm water runoff
discharge rates and velocities to maintain or reduce pre-development
downstream erosion. In addition, projects should control runoff discharge
volumes and durations to the maximum extent practicable using the site
design, source control, and treatment control requirements.
Ordinance No. 569
Page 24
Design Concept 1: Minimize Project's Impervious Footprint & Conserve
Natural Areas. The following site design options shall be considered, and
incorporated and implemented, where determined applicable and feasible
by the Director of Development Services during the site planning and
approval process, consistent with applicable General Plan policies and
other development regulations.
Minimize impervious footprint. This can be achieved in various
ways, including, but not limited to, increasing building density
(number of stories above or below ground) and developing land use
regulations seeking to limit impervious surfaces. Decreasing the
project's footprint can substantially reduce the project's impacts to
water quality and hydrologic conditions.
Conserve natural areas where feasible. This can be achieved by
concentrating or clustering development on the least
environmentally sensitive portions of a site while leaving the
remaining land in a natural, undisturbed condition. The following
list provides a guideline for determining the least sensitive portions
of the site, in order of increasing sensitivity. References should
also be made to the Poway Subarea Conservation Plan, as
appropriate.
Areas devoid of vegetation, including previously graded
agricultural fields.
Areas of non-native vegetation, disturbed habitats and
eucalyptus woodlands.
Co
Areas of chamise or mixed chaparral, and non-native
grasslands.
d. Areas containing coastal scrub communities.
e. All other upland communities.
f. Occupied habitat of sensitive species and all wetlands.
All areas necessary to maintain the viability of wildlife
corridors. Within each of the previous categories, areas
containing hillsides should be considered more sensitive
than the same category without hillsides.
Construct walkways, trails, patios, overflow parking lots and alleys,
and other Iow-traffic areas with permeable surfaces, such as
pervious concrete, porous asphalt, unit pavers, and granular
materials.
Ordinance No. 569
Page 25
Construct streets, sidewalks and parking lot aisles to the minimum
widths necessary, provided that public safety and a walkable
environment for pedestrians are not compromised.
Maximize canopy interception and water conservation by
preserving existing native trees and shrubs, and planting additional
native or drought tolerant trees and large shrubs.
6. Minimize the use of impervious surfaces, such as decorative
concrete, in the landscape design.
7. Use natural drainage systems to the maximum extent practicable.
8. Other site design options that are comparable, and equally
effective.
Co
Design Concept 2: Minimize Directly Connected Impervious Areas
(DCIAs). Priority projects shall consider, and incorporate and implement
the following design characteristics, where determined applicable and
feasible by the Director of Development Services.
1. Where landscaping is proposed, drain rooftops into adjacent
landscaping prior to discharging to the storm drain.
2. Where landscaping is proposed, drain impervious sidewalks,
walkways, trails, and patios into adjacent landscaping.
3. Other design characteristics that are comparable and equally
effective.
16.105.030
Protection of slopes and channels.
Project plans shall include storm water BMPs to decrease the potential for
erosion of slopes and/or channels, consistent with local codes and ordinances, and with
the approval of all agencies with jurisdiction, e.g., the U.S. Army Corps of Engineers,
the San Diego Regional Water Quality Control Board, and the California Department of
Fish and Game. The following design principles shall be considered, and incorporated
and implemented where determined applicable and feasible by the Director of
Development Services:
A. Convey runoff safely from the tops of slopes.
B. Vegetate slopes with native or drought tolerant vegetation.
Co
Control and treat flows in landscaping and/or other controls prior to
reaching existing natural drainage systems.
D. Stabilize permanent channel crossings.
Ordinance No. 569
Page 26
Install energy dissipaters, such as riprap, at the outlets of new storm
drains, culverts, conduits, or channels that enter unlined channels in
accordance with applicable specifications to minimize erosion. Energy
dissipaters shall be installed in such a way as to minimize impacts to
receiving waters.
Other design principles that are comparable and equally effective.
Sections:
16.106.010
16.106.020
16.106.030
16.106.040
16.106.050
Chapter 16.106
SOURCE CONTROL BMPS
Providing storm drain system stenciling and signage.
Designing outdoor material storage areas to reduce pollution
introduction.
Designing trash storage areas to reduce pollution introduction.
Using efficient irrigation systems and landscape design.
Incorporate requirements applicable to individual priority project
categories.
16.106.010
Providing storm drain system stenciling and signage.
Storm drain stencils are highly visible source control messages, typically placed
directly adjacent to storm drain inlets. The stencils contain a brief statement that
prohibits the dumping of improper materials into the urban runoff conveyance system.
Graphical icons, either illustrating anti-dumping symbols or images of receiving water
fauna, are effective supplements to the anti-dumping message. Priority projects shall
include the following requirements in the project design.
Provide stenciling or labeling of all storm drain inlets and catch basins
within the project area with prohibitive language (such as: "NO DUMPING
- I LIVE IN <<name receiving water>>") and/or graphical icons to
discourage illegal dumping.
Post signs and prohibitive language and/or graphical icons, which prohibit
illegal dumping at public access points along channels and creeks within
the project area.
C. Maintain legibility of stencils and signs.
16.106.020
Designing outdoor material storage areas to reduce pollution
introduction.
Improper storage of materials outdoors may increase the potential for toxic
compounds, oil and grease, heavy metals, nutrients, suspended solids, and other
Ordinance No. 569
Page 27
pollutants to enter the urban runoff conveyance system. Where the priority project
plans include outdoor areas for storage of hazardous materials that may contribute
pollutants to the urban runoff conveyance system, the following storm water BMPs are
required:
Hazardous materials with the potential to contaminate urban runoff shall
either be: (1) placed in an enclosure such as, but not limited to, a cabinet,
shed, or similar structure that prevents contact with runoff or spillage to
the storm water conveyance system; or (2) protected by secondary
containment structures such as berms, dikes, or curbs.
The storage area shall be paved and sufficiently impervious to contain
leaks and spills.
The storage area shall have a roof or awning to minimize direct
precipitation within the secondary containment area.
16.106.030
Designing trash storage areas to reduce pollution introduction.
All trash container areas shall meet the following requirements (limited exclusion:
detached residential homes):
Paved with an impervious surface, designed not to allow run-on from
adjoining areas, screened or walled to prevent off-site transport of trash;
and
Provide attached lids on all trash containers that exclude rain, or roof or
awning to minimize direct precipitation.
16.106.040
Using efficient irrigation systems and landscape design.
Priority projects shall design the timing and application methods of irrigation
water to minimize the runoff of excess irrigation water into the storm water conveyance
system. (Limited exclusion: detached residential homes). The following methods to
reduce excessive irrigation runoff shall be considered, and incorporated and
implemented where determined applicable and feasible by the Director of Development
Services:
^. Employing rain shutoff devices to prevent irrigation after precipitation.
Designing irrigation systems to each landscape area's specific water
requirements.
Using flow reducers or shutoff valves triggered by a pressure drop to
control water loss in the event of broken sprinkler heads or lines.
Ordinance No. 569
Page 28
Employing other comparable, equally effective, methods to reduce
irrigation water runoff.
1'6.106.050
Incorporate requirements applicable to individual priority project
categories.
Where identified in Table 2, the following requirements shall be incorporated into
applicable priority projects during the storm water BMP selection and design process.
Projects shall adhere to each of the individual priority project category requirements that
apply to the project (e.g., a restaurant with more than 15 parking spaces would be
required to incorporate the requirements for" g. Equipment Wash Areas and "h. Parking
Areas" into the project design).
Private Roads. The design of private roadway drainage shall use at least
one of the following:
Rural swale system: street sheet flows to vegetated swale or gravel
shoulder, curbs at street corners, culverts under driveways and
street crossings;
Urban curb/swale system: street slopes to curb, periodic swale
inlets drain to vegetated swale/biofilter;
Dual drainage system: First flush captured in street catch basins
and discharged to adjacent vegetated swale or gravel shoulder,
high flows connect directly to storm water conveyance system.
Other methods that are comparable and equally effective within the
project.
Bo
Residential Driveways & Guest Parking. The design of driveways and
private residential parking areas shall use one at least of the following
features.
Design driveways with shared access, flared (single lane at street)
or wheelstrips (paving only under tires); or, drain into landscaping
prior to discharging to the storm water conveyance system.
Uncovered temporary or guest parking on private residential lots
may be: paved with a permeable surface; or, designed to drain into
landscaping prior to discharging to the storm water conveyance
system.
3. Other features which are comparable and equally effective.
Co
Do
Eo
Ordinance No. 569
Page 29
Dock Areas. Loading/unloading dock areas shall include the following:
1. Cover loading dock areas, or design drainage to preclude urban
run-on and runoff.
2. Direct connections to storm drains from depressed loading docks
(truck wells) are prohibited.
3. Other features which are comparable and equally effective.
Maintenance Bays. Maintenance bays shall include the following:
1. Repair/maintenance bays shall be indoors; or, designed to preclude
urban run-on and runoff; and
2. Design a repair/maintenance bay drainage system to capture all
wash water, leaks and spills. Connect drains to a sump for
collection and disposal. Direct connection of the repair/
maintenance bays to the storm drain system is prohibited. If
required by local jurisdiction, obtain an Industrial Waste Discharge
Permit, or
3. Other features which are comparable and equally effective.
Vehicle Wash Areas. Priority projects that include areas for
washing/steam cleaning of vehicles shall use the following:
1. Self-contained, or covered with a roof or overhang;
2. Equipped with a clarifier or other pretreatment facility;
3. Propedy connected to a sanitary sewer.
4. Other features which are comparable and equally effective.
Outdoor Processing Areas. Outdoor process equipment operations, such
as rock grinding or crushing, painting or coating, grinding or sanding,
degreasing or parts cleaning, landfills, waste piles, and wastewater and
solid waste treatment and disposal, and other operations determined to be
a potential threat to water quality by the City shall adhere to the following
requirements.
1. Cover or enclose areas that would be the most significant source of
pollutants; or, slope the area toward a dead-end sump; or,
discharge to the sanitary sewer system following appropriate
treatment in accordance with conditions established by the
applicable sewer agency.
Ordinance No. 569
Page 30
2. Grade or berm area to prevent run-on from surrounding areas.
3. Installation of storm drains in areas of equipment repair is
prohibited.
4. Other features which are comparable or equally effective.
Equipment Wash Areas. Outdoor equipment/accessory washing and
steam cleaning activities at priority projects shall use the following:
1. Be self-contained; or covered with a roof or overhang;
2. Be equipped with a clarifier, grease trap or other pretreatment
facility, as appropriate;
3. Properly connected to a sanitary sewer.
4. Other features which are comparable or equally effective.
Parking Areas. To minimize the offsite transport of pollutants from parking
areas, the following design concepts shall be considered, and
incorporated and implemented where determined applicable and feasible
by the Director of Development Services:
1. Where landscaping is proposed in parking areas, incorporate
landscape areas into the drainage design,
2. Overflow parking (parking stalls provided in excess of the City's
minimum parking requirements) may be constructed with
permeable paving.
3. Other design concepts that are comparable and equally effective,
Roadways. Priority roadway projects shall select treatment control BMPs
following the treatment control selection procedure identified in this
division entitled, "Establishing Storm Water BMPs.'
Fueling Area. Non-retail fuel dispensing areas shall contain the following:
1. Overhanging roof structure or canopy. The cover's minimum
dimensions must be equal to or greater than the area within the
grade break. The cover must not drain onto the fuel dispensing
area and the downspouts must be routed to prevent drainage
across the fueling area. The fueling area shall drain to the project's
treatment control BMP(s) prior to discharging to the storm water
conveyance system.
Ordinance No. 569
Page 31
Paved with Portland cement concrete (or equivalent smooth
impervious surface). The use of asphalt concrete shall be
prohibited.
Have an appropriate slope to prevent ponding, and must be
separated from the rest of the site by a grade break that prevents
run-on of urban runoff.
At a minimum, the concrete fuel dispensing area must extend 6.5
feet (2.0 meters) from the corner of each fuel dispenser, or the
length at which the hose and nozzle assembly may be operated
plus 1 foot (0.3 meter), whichever is less.
Hillside Landscaping. Hillside areas that are disturbed by project
development shall be landscaped with deep-rooted, drought tolerant plant
species selected for erosion control, satisfactory to the Director of
Development Services.
Chapter 16.107
Sections:
16.107.010
16.107.020
16.107.030
16.107.040
16.107.050
16.107.060
16.107.070
TREATMENT CONTROL BMPS
Treatment control BMPs objectives.
Design to treatment control BMPs standards.
Volume based BMPs.
Flow based BMPs.
Limited exclusions.
Locating BMPs near pollutant sources.
Restrictions on use of infiltration BMPs.
16.107.010
Treatment control BMPs objectives.
Minimizing a development's detrimental effects on water quality can be
most effectively achieved through the use of a combination of site design,
source and treatment control storm water BMPs. Where projects have
been designed to minimize, to the maximum extent practicable, the
introduction of anticipated pollutants of concern that may result in
significant impacts to the receiving waters through the implementation of
site design and source control storm water BMPs, the development would
still have the potential for pollutants of concern to enter the storm water
conveyance system. Therefore, priority projects shall be designed to
remove pollutants of concern from the storm water conveyance system to
the maximum extent practicable through the incorporation and
implementation of treatment control BMPs.
In meeting the requirements in this section, priority projects shall
implement a single or combination of storm water BMPs that will remove
Ordinance No. 569
Page 32
anticipated pollutants of concern, as identified by the procedure of this
division, in site runoff to the maximum extent practicable. Treatment
control BMPs must be implemented unless a waiver is granted to the
project by the Director of Development Services based on the infeasibility
of any treatment control BMP.
16.107.020
Design to treatment control BMPs standards.
All priority projects shall design, construct and implement structural treatment
control BMPs that meet the design standards of this section, unless specifically
exempted by the limited exclusions. Structural treatment control BMPs required by this
section shall be operational prior to the use of any dependent development, and shall
be located and designed in accordance with the requirements of this division.
16.107.030
Structural treatment control volume based BMPs.
either:
Volume-based BMPs shall be designed to mitigate (infiltrate, filter, or treat)
Ao
Volume of runoff produced from a 24-hour 85th-percentile storm event, as
determined from the local historical rainfall record (0.6 inch approximate
average for the San Diego County area). This volume is not a single
volume to be applied to all of San Diego County as the size of the 85th
percentile is different for various parts of the County. Project proponents
may calculate the 85th percentile using local rain data. In addition,
isopluvial maps contained in the County of San Diego Hydrology Manual
may be used to extrapolate rainfall data to areas where insufficient data
exists; or
Volume of runoff produced by the 85th-percentile 24-hour runoff event,
determined as the maximized capture urban runoff volume for the area,
from the formula recommended in Urban Runoff Quality Management,
WEF Manual of Practice No. 23/ ASCE Manual of Practice No. 87, (1998);
or
Co
The volume of annual runoff based on unit basin storage volume, to
achieve 90 percent or more volume treatment by the method
recommended in California Storm water Best Management Practices
Handbook- Industrial/Commercial, (1993); or
The volume of runoff, as determined from the local historical rainfall
record, that achieves approximately the same reduction in pollutant loads
and flows as achieved by mitigation of the 85th percentile 24-hour runoff
event. Under this volume criterion, houdy rainfall data may be used to
calculate the 85th percentile storm event, where each storm event is
identified by its separation from other storm events by at least six hours of
no rain.
Ordinance No. 569
Page 33
16.107.040
Structural treatment control flow based BMPs.
As an alternative to volume-based BMP's, structural treatment controls may be
designed as flow-based BMP's. Flow-based BMPs shall be designed to mitigate
(infiltrate, filter, or treat) either:
The maximum flow rate of runoff produced from a rainfall intensity of 0.2
inch of rainfall per hour for each hour of a storm event; or
The maximum flow rate of runoff produced by the 85th-percentile hourly
rainfall intensity, as determined from the local historical rainfall record,
multiplied by a factor of two, for each hour of a storm event; or
The maximum flow rate of runoff, as determined from the local historical
rainfall record, that achieves approximately the same reduction in pollutant
loads and flows as achieved by mitigation of the 85th-percentile hourly
rainfall intensity multiplied by a factor of two, for each hour of a storm
event.
16.107.050
Limited exclusions.
Ao
Proposed restaurants, where the land area for development or
redevelopment is less than 5,000 square feet, are excluded from the
numerical sizing criteria requirements listed for structural treatment control
volume based BMP's.
Where significant redevelopment results in an increase of less than 50
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 for structural treatment control
volume based apply only to the addition, and not to the entire
development.
16.107.060
Locating BMPs near pollutant sources.
Structural treatment control storm water BMPs should be implemented close to
pollutant sources to minimize costs and maximize pollutant removal prior to runoff
entering receiving waters. Such BMPs may be located on- or off-site, used singly or in
combination, or shared by multiple new developments, pursuant to the following
requirements:
All structural treatment control BMPs shall be located so as to infiltrate,
filter, and/or treat the required runoff volume or flow prior to its discharge
to any receiving water body supporting beneficial uses;
Multiple post-construction structural treatment control BMPs for a single
priority development project shall collectively be designed to comply with
the design standards for structural treatment control volume based BMP's;
Ordinance No. 569
Page 34
Shared storm water BMPs shall be operational prior to the use of any
dependent development or phase of development. The shared BMPs
shall only be required to treat the dependent developments or phases of
development that are in use;
Interim storm water BMPs that provide equivalent or greater treatment
than is required by structural treatment control volume based BMP's may
be implemented by a dependent development until each shared BMP is
operational. If interim BMPs are selected, the BMPs shall remain in use
until permanent BMPs are operational.
16.107,070
Restrictions on use of infiltration BMPs.
At a minimum, use of structural treatment BMPs that are designed to primarily
function as infiltration devices shall meet the following conditions. These conditions do
not apply to structural treatment BMPs which allow incidental infiltration and are not
designed to primarily function as infiltration devices (such as grassy swales, detention
basins, vegetated buffer strips, constructed wetlands, etc.).
Urban runoff from commercial developments shall undergo pretreatment
to remove both physical and chemical contaminants, such as
sedimentation or filtration, prior to infiltration.
Bo
All dry weather flows shall be diverted from infiltration devices except for
those non-storm water discharges authorized pursuant to 40 CFR
122.26(d)(2)(iv)(B)(1): diverted stream flows, rising ground waters,
uncontaminated ground water infiltration [as defined at 40 CFR
35.2005(20)] to storm water conveyance systems, uncontaminated
pumped ground water, foundation drains, springs, water from crawl space
pumps, footing drains, air conditioning condensation, flow from dparian
habitats and wetlands, water line flushing, landscape irrigation, discharges
from potable water sources other than water main breaks, irrigation water,
individual residential car washing, and dechlorinated swimming pool
discharges.
Pollution prevention and source control BMPs shall be implemented at a
level appropriate to protect groundwater quality at sites where infiltration
structural treatment BMPs are to be used.
Do
The vertical distance from the base of any infiltration structural treatment
BMP to the seasonal high groundwater mark shall be at least 10 feet or as
determined on an individual, site-specific basis by the Director of
Development Services. Where groundwater does not support beneficial
uses, this vertical distance criterion may be reduced, provided
groundwater quality is maintained.
The soil through which infiltration is to occur shall have physical and
chemical characteristics (such as appropriate cation exchange capacity,
Ordinance No. 569
Page 35
organic content, clay content, and infiltration rate) that are adequate for
proper infiltration durations and treatment of urban runoff for the protection
of groundwater beneficial uses.
Infiltration structural treatment BMPs shall not be used for areas of
industrial or light industrial activity; areas subject to high vehicular traffic
(25,000 or greater average daily traffic on main roadway or 15,000 or
more average daily traffic on any intersecting roadway); automotive repair
shops; car washes; fleet storage areas (bus, truck, etc.); plant nurseries;
and other high threat to water quality land uses and activities as
designated by the Director of Development.
The horizontal distance between the base of any infiltration structural BMP and
any water supply wells shall be 100 feet or as determined on an individual, site-
specific basis by the Director of Development Services.
Chapter 16.108
PROVIDING PROOF OF ONGOING BMP MAINTENANCE
Se~ions:
16.108.010
16.108.020
16.108.030
16.108.040
Maintenance mechanism to be in place before acceptance.
Maintenance mechanisms.
Verification mechanisms.
Maintenance requirements.
16.108.010
Maintenance mechanism to be in place before acceptance.
Structural BMPs shall not be considered "effective," and shall not be accepted as
meeting the MEP standard, unless a mechanism is in place that will ensure ongoing
long-term maintenance of all structural BMPs. As part of project review, if a project
proponent is required to include interim or permanent structural BMPs in project plans,
and if the Director of Development Services does not provide a mechanism for BMP
maintenance, the project proponent shall provide verification of maintenance
requirements through such means as may be appropriate, at the discretion of the
Director of Development Services, including, but not limited to covenants, legal
agreements, maintenance agreements, and/or conditional use permits.
16.108.020
Maintenance mechanisms.
Public equity maintenance. The City Council may approve a public or
acceptable quasi-public entity (e.g., the County Flood Control District, or
annex to an existing assessment district, an existing utility district, a state
or federal resource agency, or a conservation conservancy) to assume
responsibility for maintenance, repair and replacement of the BMP.
Unless acceptable to the City Council, public entity maintenance
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16.108.030
Ao
Ordinance No. 569
Page 36
agreements shall ensure estimated costs are front-funded or reliably
guaranteed, (e.g., through a trust fund, assessment district fees, bond,
letter of credit or similar means). In addition, the City Council may seek
protection from liability by appropriate releases and indemnities. The City
Council shall have the authority to approve storm water BMPs proposed
for transfer to any other public entity within its jurisdiction before
installation. The City Council shall be involved in the negotiation of
maintenance requirements with any other public entities accepting
maintenance responsibilities within their respective jurisdictions; and in
negotiations with the resource agencies responsible for issuing permits for
the construction and/or maintenance of the facilities. The City Council
must be identified as a third party beneficiary empowered to enforce any
such maintenance agreement within their respective jurisdictions.
Project proponent agreement to maintain storm water BMPs: The City
Council may enter into a contract with the project proponent obliging the
project proponent to maintain, repair and replace the storm water BMP as
necessary into perpetuity. Security may be required.
Assessment districts: The City Council may approve an Assessment
District or other funding mechanism created by the project proponent to
provide funds for storm water BMP maintenance, repair and replacement
on an ongoing basis. Any agreement with such a District shall be subject
to the Public Entity Maintenance Provisions above.
Lease provisions: In those cases where the City holds title to the land in
question, and the land is being leased to another party for private or public
use, the City Council may assure storm water BMP maintenance, repair
and replacement through conditions in the lease.
Conditional Use Permits: For discretionary projects only, the City Council
may assure maintenance of storm water BMPs through the inclusion of
maintenance conditions in the Conditional Use Permit. Security may be
required.
Alternative mechanisms: The City Council may accept alternative
maintenance mechanisms, if such mechanisms are as protective those
listed above.
Verification mechanisms.
For discretionary projects, the City approved method of storm water BMP
maintenance shall be incorporated into the project's permit, and shall be
consistent with permits issued by resource agencies, before City approval
of discretionary permits.
16.109.10
A.
Ordinance No. 569
Page 37
For projects requiring only ministerial permits, the approved method of
storm water BMP maintenance shall be incorporated into the permit
conditions before the issuance of any ministerial permits.
In all instances, the project proponent shall provide proof of execution of
an approved method of maintenance repair and replacement before the
issuance of construction approvals.
Public projects that are not required to obtain permits shall be responsible
for ensuring that an approved method of storm water BMP maintenance
repair and replacement is executed prior to the commencement of
construction.
For all properties, the verification mechanism will include the project
proponent's signed statement, as part of the project application, accepting
responsibility for all structural BMP maintenance, repair and replacement,
until a City approved entity agrees to assume responsibility for structural
BMP maintenance, repair and replacement.
Maintenance requirements.
Operation & Maintenance (O&M) Plan: A copy of an Operation &
Maintenance (O&M) plan, prepared by the project proponent satisfactory
to the Director of Development Services shall be attached to the approved
maintenance agreement, which describes the designated responsible
party to manage the storm water BMP(s), employee's training program
and duties, operating schedule, maintenance frequency, routine service
schedule, specific maintenance activities, copies of resource agency
permits, and any other necessary activities. At a minimum, maintenance
agreements shall require the inspection and servicing of all structural
BMPs on an annual basis. The project proponent maintenance entity shall
complete and maintain O&M forms to document all maintenance
requirements. Parties responsible for the O&M plan shall retain records
for at least 5 years. These documents shall be made available to the City
for inspection upon request at any time.
Access Easement/Agreement: As part of the maintenance mechanism
selected above, it shall include a copy of an executed access easement
that shall be binding on the land throughout the life of the project, until
such time that the storm water BMP requiring access is replaced,
satisfactory to the Director of Development Services.
Ordinance No. 569
Page 38
Chapter 16.109
WAIVER OF STRUCTURAL TREATMENT BMP REQUIREMENTS
Sections:
16.109.10
16.109.010
A.
Waiver of structural treatment BMP requirements.
Waiver of structural treatment BMP requirements.
The requirement of implementing structural treatment BMPs may be
waived if infeasibility can be established. A waiver of infeasibility shall be
granted only when all available structural treatment BMPs have been
considered and rejected as infeasible.
Waivers may only be granted from structural treatment BMP and structural
treatment BMP sizing requirements. Priority development projects,
whether or not granted a waiver may not cause or contribute to an
exceedance of water quality objectives. Pollutants in runoff from projects
granted a waiver must still be reduced to the maximum extent practicable.
EFFECTIVE DATE: This Ordinance shall take effect and be in force thirty (30)
days after the date of its passage; and before the expiration of fifteen (15) days after its
passage, it shall be published once with the names of members voting for and against
the same in the Poway News Chieftain, a newspaper of general circulation published in
the City of Poway.
Introduced and first read at a Regular Meeting of the City Council of the City of
Poway held the 19th day of November 2002, and thereafter PASSED AND ADOPTED
at a regular meeting of said City Council held the 3rd day of December 2002, by the
following roll call vote:
AYES:
EMERY, GOLDBY, HIGGINSON, REXFORD, CAFAGNA
NOES: NONE
ABSENT: NONE
ABSTAIN: NONE
ATTEST:
nne Peoples, 'City ~lerk
Michael P. ~
~.,~ Mayor