HomeMy WebLinkAbout2018-032 Construction Stormwater Runoff; YMC Amendment Ch. 7.82 ORDINANCE NO. 2018-032
AN ORDINANCE amending the City of Yakima Municipal Code Chapter 7.82 Construction
Stormwater Runoff
WHEREAS, the City of Yakima is required to comply with the State of Washington's
Eastern Washington Phase II Municipal Stormwater Permit, hereinafter referred to as "Permit";
and
WHEREAS, the City's Permit requires it to review Stormwater Pollution Prevention Plans
(SWPPP) for all projects one acre or more to be in compliance with its permit; and
WHEREAS, the City of Yakima has allowed the use of Low Impact Development
techniques as a best management practice informally and should codify the practice to formally
allow such practices, as allowed in its Permit; and
WHEREAS, responsible parties should be required to handle and dispose of on-site litter,
discarded building materials, concrete truck washouts, chemicals, and sanitary waste in a manner
that does not cause contamination of stormwater and construction sites, in compliance with its
Permit; and
WHEREAS, the City's Permit requires codified language concerning stormwater runoff
treatment and the State All Known, Available, and Reasonable methods of prevention, control
and Treatment (AKART) requirements to protect water quality; and
WHEREAS, the City Council of the City of Yakima finds that it is in the best interests of
the City of Yakima and its residents to amend Chapter 7.82 to review SWPPP for projects one
acre or larger, codify low impact development technique use, and require responsible parties to
dispose of on-site litter and waste; now, therefore,
BE IT ORDAINED BY THE CITY OF YAKIMA:
Section 1. Section 7.82.020 Definitions of the City of Yakima Municipal Code is hereby
amended to read as follows:
7.82.020 Definitions.
This section provides definitions for the terms and phrases used in this chapter. Where any of
these definitions conflict with definitions used in other chapters of the Yakima Municipal Code,
the definitions in this section shall prevail for the purpose of this chapter.
"Applicant" means a person, party, firm, corporation, or other legal entity that proposes a
development, construction or use on a site.
"Best management practices (BMPs)" means schedules of activities, prohibitions of practices,
maintenance procedures, and other physical, structural and/or managerial practices to prevent
or reduce the pollution of waters of the state. BMPs include treatment systems, operating
procedures, and practices to control: stormwater associated with construction activity, spillage
or leaks, sludge or waste disposal, or drainage from raw material storage.
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"Certified erosion and sediment control lead" or"CESCL" means a person who has current
certification through an approved erosion and sediment control training program that meets the
minimum training standards established by Ecology.
"Channel" or"waterway" means an open conduit, either naturally or artificially created, which
periodically or continuously contains moving water, or which forms a connecting link between
two bodies of water.
"Clearing" or"site clearing" means the removal of timber, brush, grass, ground cover or other
vegetative matter from a site.
"Common plan of development" means a site where multiple separate and distinct construction
activities may be taking place at different times on different schedules, but still under a single
plan. Examples include: phased projects and projects with multiple filings or lots, even if the
separate phases or filings/lots will be constructed under separate contract or by separate
owners (e.g., a development where lots are sold to separate builders); a development plan that
may be phased over multiple years, but is still under a consistent plan for long-term
development; and projects in a contiguous area that may be unrelated but still under the same
contract, such as construction of a building extension and a new parking lot at the same facility.
If the project is part of a common plan of development or sale, the disturbed area of the entire
plan shall be used in determining permit requirements.
"Detention" means the release of stormwater runoff from the site at a slower rate than it is
collected by the stormwater facility system, the difference being held in temporary storage with
the goals of controlling peak discharge rates and providing gravity settling of pollutants.
"Development" means new development, redevelopment, or both. See definitions for each.
"Director" means the director of community and economic development, designated city
employee or authorized representative.
"Ecology" means the Washington State Department of Ecology.
"Erosion and sediment control" means any temporary or permanent measures taken to reduce
erosion, control siltation and sedimentation, and ensure that sediment-laden water does not
leave the site.
"Erosion and sediment control BMPs" means BMPs that are intended to prevent erosion and
sedimentation, such as preserving natural vegetation, seeding, mulching and matting, plastic
covering, filter fences, sediment traps, and ponds. Erosion and sediment control BMPs are
synonymous with stabilization and structural BMPs.
"Finish grade" means the final grade of the site which conforms to an approved plan.
"Grading" means any excavation, filling, or combination thereof.
"Impaired waters" means those streams, rivers and lakes that currently do not meet their
designated use classification and associated water quality standards under the Clean Water Act
and listed on the most current state of Washington 303(d) list.
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"Land development" or"development" means any clearing, excavation, dredging, drilling, filling,
dumping, removal of earth and mineral materials, or other permanent or temporary modification
of a site up to, but not including, construction as defined in this chapter. For the purpose of this
chapter, "development" also means any manmade change to improved or unimproved real
estate located within the special flood hazard area, including but not limited to buildings or other
structures, mining, dredging, filling, grading, paving, excavation, drilling, temporary or
permanent storage of equipment and works defined in this chapter.
"Land disturbing activity" means any activity that results in movement of earth, or a change in
the existing soil cover (both vegetative and nonvegetative) and/or the existing soil topography.
Land disturbing activities include, but are not limited to, clearing, grading, filling, and excavation.
Compaction associated with stabilization of structures and road construction shall also be
considered a land disturbing activity. Vegetation maintenance practices are not considered land
disturbing activity.
"Low impact development" means a stormwater and land use management strategy that strives
to mimic pre-disturbance hydrologic processes of infiltration, filtration, storage, evaporation and
transpiration by emphasizing conservation, use of on-site natural features, site planning, and
distributed stormwater management practices that are integrated into a project design.
"Municipal separate storm sewer system" or"MS4" means a conveyance, or system of
conveyances (including roads with drainage systems, municipal streets, catch basins, curbs,
gutters, ditches, manmade channels, or storm drains): (i) owned or operated by a state, city,
town, borough, county, parish, district, association, or other public body (created by or pursuant
to state law) having jurisdiction over disposal of wastes, storm water, or other wastes, including
special districts under state law such as a sewer district, flood control district or drainage district,
or similar entity, or an Indian tribe or an authorized Indian tribal organization, or a designated
and approved management agency under Section 208 of the CWA that discharges to waters of
the United States; (ii) designed or used for collecting or conveying stormwater; (iii) which is not
a combined sewer; and (iv) which is not part of a publicly owned treatment works (POTW) as
defined at 40 CFR 122.2.
"National Pollutant Discharge Elimination System" or"NPDES" means the national program for
issuing, modifying, revoking, and reissuing, terminating, monitoring and enforcing permits, and
imposing and enforcing pretreatment requirements, under Sections 307, 402, 318, and 405 of
the Federal Clean Water Act, for the discharge of pollutants to surface waters of the state from
point sources. These permits are referred to as NPDES permits and, in Washington State, are
administered by the Washington State Department of Ecology.
"New development" means land disturbing activities, including Class IV general forest practices
development, including construction or installation of a building or other structure; creation of
impervious surfaces; and subdivision, short subdivision and binding site plans, as defined and
applied in RCW Chapter 58.17. Projects meeting the definition of redevelopment shall not be
considered new development.
"Nonstormwater discharge" means any discharge to the storm drain system that is not
composed entirely of stormwater.
"Owner(s)" or "property owner(s)" means the legal owner or owners of the property. As used
herein, owner also refers to, in the appropriate context: (i) any other person authorized to act as
the agent for the owner; (ii) any person who submits a stormwater management concept or
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design plan for approval or requests issuance of a permit, when required, authorizing land
development to commence; and (iii) any person responsible for complying with an approved
stormwater management design plan.
"Point source" means any discernible, confined, and discrete conveyance, including but not
limited to any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, and container from
which pollutants are or may be discharged to surface waters of the state. This term does not
include return flows from irrigated agriculture.
"Project site" means that portion of a property, properties, or right-of-way subject to land
disturbing activities, and new or replaced impervious surfaces.
"Public development" or"public" as used in this chapter shall mean any land development or
redevelopment upon any real property, or interest therein, belonging to the city or a trust or
authority of which the city is a beneficiary. Public development shall also include private
development whenever all or a portion thereof will eventually be dedicated or provided for
ownership, operation and/or maintenance to the city or a public trust or authority of which the
city is a beneficiary.
"Receiving stream or receiving water" means bodies of water or surface water systems to which
surface runoff is discharged via a point source of stormwater or via sheet flow.
"Redevelopment" means, on a site that is already substantially developed, the replacement or
improvement of impervious surfaces, including buildings and other structures, and replacement
or improvement of impervious parking and road surfaces, that is not part of a routine
maintenance activity. (Any new impervious surfaces created by a redevelopment project are
subject to the requirements for new development.)
"Responsible party" means any individual, partnership, co-partnership, firm, company,
corporation, association, joint stock company, trust, estate, governmental entity, or any other
legal entity, or their legal representatives, agents, or assigns, that is named on a stormwater
maintenance agreement as responsible for long-term operation and maintenance of one or
more stormwater BMPs.
"Rough grade" means a stage where grade conforms approximately to an approved plan.
"Sediment control" means measures that prevent eroded sediment from leaving the site.
Site. See "Project site."
"Source control BMPs" means physical, structural or mechanical devices or facilities that are
intended to prevent pollutants from entering stormwater. A few examples of source control
BMPs are erosion control practices, maintenance of stormwater facilities, constructing roofs
over storage and working areas, and directing wash water and similar discharges to the sanitary
sewer or a dead-end sump.
"Special flood hazard area (SFHA)" means a Federal Emergency Management Agency (FEMA)
identified high-risk flood area where flood insurance is mandatory for properties. An area having
special flood, mudflow, or flood-related erosion hazards, and shown on a flood hazard boundary
map or a flood insurance rate map as Zone A, AO, Al-A30, AE, A99, AH, AR, AR/A, AR/AE,
AR/AH, AR/AO, AR/Al-A30, Vl-V30, VE, or V.
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"Stabilization" means the use of practices that prevent exposed soil from eroding.
"Stop work order" means an order issued that requires that all construction activity on a site be
stopped.
"Stormwater authority" means the department or agency, and its authorized agents, which is
responsible for coordinating the review, approval, and permit process as defined by this chapter.
"Stormwater management" means the use of structural or nonstructural practices that are
designed to reduce stormwater runoff pollutant loads, discharge volumes, peak flow discharge
rates and detrimental changes in stream temperature that affect water quality and habitat.
"Stormwater pollution prevention plan" or"SWPPP" or"construction SWPPP" means a set of
plans prepared by or under the direction of a licensed professional engineer indicating the
specific measures and sequencing to be used to control sediment and erosion on a
development site during and after construction.
"Stormwater runoff" or"stormwater" means runoff during and following precipitation and
snowmelt events, including surface runoff, drainage and interflow.
"Stream" means an area where surface waters flow sufficiently to produce a defined channel or
bed. A defined channel or bed is an area that demonstrates clear evidence of the passage of
water including, but not limited to, hydraulically sorted sediments, or the removal of vegetative
litter or loosely rooted vegetation by the action of moving water. The channel or bed need not
contain water year-round. This definition is not meant to include irrigation ditches, canals,
stormwater runoff devices or other entirely artificial watercourses, unless they are used to
convey streams naturally occurring prior to construction. Those topographic features that
resemble streams but have no defined channels (i.e., swales) shall be considered streams
when hydrologic and hydraulic analyses done pursuant to a development proposal predict
formation of a defined channel after development.
"Structure" means anything constructed or erected which requires location on the ground or
attached to something having a location on the ground.
"Underground injection control" or"UIC" or"UIC well" means a manmade subsurface fluid
distribution system designed to discharge fluids into the ground and consists of an assemblage
of perforated pipes, drain tiles, or other similar mechanisms, or a dug hole that is deeper than
the largest surface dimension. UICs can be publicly or privately owned.
"Watercourse" means any regulated body of water, including, but not limited to, lakes, ponds,
rivers, streams, and bodies of water delineated by the Washington Department of Ecology.
Waterway. See "Channel."
"Waters of the state" includes those waters as defined as "waters of the United States" in 40
CFR 122.2 within the geographic boundaries of Washington State and "waters of the state" as
defined in Chapter 90.48 RCW which includes: lakes, rivers, ponds, streams, inland waters,
underground waters, salt waters and all other surface waters and water courses within the
jurisdiction of the state of Washington. (Ord. 2010-07 § 1 (part), 2010).
Section 2. Section 7.82.090 Exemptions of the City of Yakima Municipal Code is
hereby amended to read as follows:
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7.82.090 Exemptions.
Activities Exempt. The following activities are exempt from this chapter:
(1) Public and private development or redevelopment that disturbs less than one acre through
clearing, grading, excavating, or stockpiling of fill material, including the cumulative acreage of
the entire project whether in a single or in a multiphase project.
(2) Stormwater from any site covered under an existing NPDES individual permit in which
stormwater management and/or treatment requirements are included for all stormwater
discharges associated with construction activity.
(3) Any emergency activity that is immediately necessary for the protection of life, property, or
natural resources, as determined by the director.
(4) Forest practices regulated under Title 222 WAC. Conversions of forest lands to other uses
are not exempt. Silvicultural roads that are used to access other land uses subject to this
chapter are not exempt.
(5) Commercial agriculture practices involving working the land for production. Construction of
impervious surfaces is not exempt.
(6) Oil and gas field activities such as construction of drilling sites, waste management pits,
and access roads, as well as construction of transportation and treatment infrastructure such as
pipelines, natural gas treatment plants, natural gas pipeline compressor stations, and crude oil
pumping stations.
a) Discharge of sediment or other stormwater pollution from an oil or gas field activity is
subject to the illicit discharge ordinance, YMC Chapter 7.85.
(7) Routine maintenance that is performed to maintain the original line and grade, hydraulic
capacity, or original purpose of a facility. (Ord. 2010-07 § 1 (part), 2010).
Section 3. Section 7.82.100 Design Manuals of the City of Yakima Municipal Code is
hereby amended to read as follows:
7.82.100 Design Manuals
(1) The city will utilize information including technical specifications of the latest edition of the
Stormwater Manual for Eastern Washington (or approved local equivalent), or another technical
stormwater manual approved by Ecology, as the basis for decisions about design,
implementation, maintenance, and performance of structural and nonstructural post-
construction stormwater BMPs. The Stormwater Management Manual for Eastern Washington
(or approved local equivalent) includes a list of acceptable stormwater treatment practices,
including specific design criteria for each stormwater practice. Use of BMPs from other technical
stormwater manuals approved by Ecology shall be consistent with city climate, soils, and
specific site conditions appropriate for said BMP use. Stormwater practices that are designed,
constructed, and maintained in accordance with these design and sizing criteria will be
presumed to meet the minimum water quality performance standards of the Eastern
Washington NPDES Phase II Municipal Stormwater Permit requirements.
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(2) Use of BMPs not designed, constructed, and maintained in accordance with manuals
identified in subsection (1) of this section shall be subject to city approval and must be
monitored for performance to demonstrate that they meet the minimum water quality
performance standards of the Eastern Washington NPDES Phase II Municipal Stormwater
Permit requirements.
(3) Non-structural preventive actions and source reduction approaches such as Low Impact
Development measures to minimize the creation of impervious surfaces and measures to
minimize the disturbance of native soils and vegetation shall be allowed provided they conform
to the Yakima Regional Low Impact Development Stormwater Design Manual (2011). Use of
Low Impact Development measures shall be subject to city approval to ensure applicable
designs take into account site conditions and long term maintenance.(Ord. 2010-07 § 1 (part),
2010).
Section 4. Section 7.82.130 Construction stormwater pollution prevention plan
(SWPPP) of the City of Yakima Municipal Code is hereby amended to read as follows:
7.82.130 Construction stormwater pollution prevention plan (SWPPP).
(1) Construction SWPPP Required.
a) Projects meeting the regulatory threshold and not qualifying for an erosivity waiver
from Washington State Department of Ecology shall prepare a stormwater pollution
prevention plan (SWPPP) for construction activity. The SWPPP shall be implemented
beginning with initial soil disturbance and continue until final stabilization.
b) Each SWPPP shall bear the name(s) and address(es) of the owner or developer of
the site, and of any consulting firm retained by the applicant together with the name of the
applicant's principal contact at such firm and shall be accompanied by a filing fee.
c) Each SWPPP shall include a statement that any land clearing, construction, or
development involving the movement of earth shall be in accordance with the SWPPP and
that a certified erosion and sediment control lead (CESCL) shall be on-site or on call for
the entire length of the project.
d) SWPPP Compliance. SWPPP compliance may be obtained in one of four ways, as
follows:
1. Preparation, submittal and implementation of a construction SWPPP in
accordance with subsection (2) of this section.
I. All such projects shall provide a copy of the construction SWPPP prepared
in accordance with Ecology requirements, including an anticipated schedule, to
the director at least twenty-four hours before any land disturbing activity.
2. Preparation and implementation of a SWPPP developed in accordance with the
requirements of Ecology's general NPDES permit for stormwater discharges
associated with construction activities.
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I. All such projects shall provide a copy of the construction SWPPP prepared
in accordance with Ecology requirements, including an anticipated schedule, to
the director at least twenty-four hours before any land disturbing activity.
3. Public and private development or redevelopment that qualifies for and obtains
an erosivity waiver in accordance with requirements of the Washington State
Department of Ecology general NPDES permit for stormwater discharges associated
with construction activities.
4. Public and private development or redevelopment that qualifies for and obtains
an erosivity waiver in accordance with the following:
I. The erosivity waiver contains the following conditions:
i. The total acres to be disturbed within the entire construction project or
common plan of development does not exceed five acres; and
ii. Calculation of Erosivity "R" Factor.
1. The project's rainfall erosivity factor ("R" Factor) must be less than five
during the period of construction activity, as calculated using the Texas A&M
University online rainfall erosivity calculator at: http://ei.tamu.edu/. The period of
construction activity begins at initial earth disturbance and ends with final
stabilization; and, in addition
iii. Operators must submit a complete erosivity waiver certification statement at
least one week prior to commencing land disturbing activities. Certification must
include:
1. A statement that the operator will comply with applicable local stormwater
requirements; and
2. A statement that the operator will implement appropriate erosion and
sediment control BMPs to prevent violations of water quality standards;
iv. This waiver is not available for facilities declared a significant contributor of
pollutants by Ecology; and
v. The project has no other discharges including, but not limited to, excavation
de-watering, wash waters and hydrostatic test waters.
II. Appropriate erosion and sediment control BMPs be implemented to prevent
violations of water quality standards.
Ill. Discharge of sediment or other pollutants from a construction site qualifying
under an erosivity waiver is subject to the illicit discharge ordinance, YMC
Chapter 7.85.
5. For projects subject to YMC Chapter 7.83, Post-Construction Stormwater Runoff,
a construction SWPPP or erosivity waiver prepared in accordance with this chapter is
required as part of the stormwater site plan.
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(2) Construction SWPPP Elements.
a) The construction SWPPP shall include the twelve elements of a construction SWPPP.
Guidance for design and implementation of the twelve elements in a construction SWPPP
are found in the Stormwater Management Manual for Eastern Washington dated 2004 (or
approved local equivalent).
1- Preserve Vegetation/Mark Clearing Limits.
I. Prior to beginning land disturbing activities, including clearing and grading,
clearly mark all clearing limits, sensitive areas and their buffers, and trees that
are to be preserved within the construction area.
II. The duff layer, native top soil, and natural vegetation shall be retained in an
undisturbed state to the maximum degree practicable.
2- Establish Construction Access.
I. Construction vehicle access and exit shall be limited to one route, if possible.
II. Access points shall be stabilized with a pad of quarry spalls, crushed rock,
or other equivalent BMP to minimize the tracking of sediment onto public roads.
III. Wheel wash or tire baths shall be located on-site if the stabilized
construction entrance is not effective in preventing sediment from being tracked
onto public roads.
IV. If sediment is tracked off-site, public roads shall be cleaned thoroughly at
the end of each day, or more frequently during wet weather. Sediment shall be
removed from roads by shoveling or pickup sweeping and shall be transported
to a controlled sediment disposal area.
V. Street washing is allowed only after sediment is removed in accordance
with subsection (2)(a)(2)(IV) of this section. Street wash wastewater shall be
controlled by pumping back on-site or otherwise be prevented from discharging
into systems tributary to waters of the state.
3- Control Flow Rates.
I. Properties and waterways downstream from development sites shall be
protected from erosion due to increases in the velocity and peak volumetric flow
rate of stormwater runoff from the project site, as required by local plan approval
authority.
II. Where necessary to comply with subsection (2)(a)(3)(I) of this section,
stormwater retention or detention facilities shall be constructed as one of the first
steps in grading. Detention facilities shall be functional prior to construction of
site improvements (e.g., impervious surfaces).
III. If permanent infiltration ponds are used for flow control during construction,
these facilities shall be protected from siltation during the construction phase.
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4- Install Sediment Controls.
I. Stormwater runoff from disturbed areas shall pass through a sediment pond
or other appropriate sediment removal BMP, prior to leaving a construction site
or prior to discharge to an infiltration facility. Runoff from fully stabilized areas
may be discharged without a sediment removal BMP, but shall meet the flow
control performance standard of subsection (2)(a)(3)(I) of this section.
II. Sediment control BMPs (sediment ponds, traps, filters, etc.) shall be
constructed as one of the first steps in grading. These BMPs shall be functional
before other land disturbing activities take place.
III. BMPs intended to trap sediment on-site shall be located in a manner to
avoid interference with the movement of juvenile salmonids attempting to enter
off-channel areas or drainages.
5- Stabilize Soils.
I. Exposed and unworked soils shall be stabilized by application of effective
BMPs that prevent erosion. Applicable BMPs include, but are not limited to:
temporary and permanent seeding, sodding, mulching, plastic covering, erosion
control fabrics and matting, soil application of polyacrylamide (PAM), the early
application of gravel base on areas to be paved, and dust control.
II. No soils shall remain exposed and unworked for more than the time periods
set forth below to prevent erosion:
i. For areas with mean annual precipitation of twelve inches or greater:
1. During the dry season (July 1st—September 30th): ten days.
2. During the wet season (October 1st—June 30th): five days.
ii. For areas with mean annual precipitation less than twelve inches:
1. During the dry season (July 1st—September 30th): thirty days.
2. During the wet season (October 1st—June 30th): fifteen days.
III. Soils shall be stabilized at the end of the shift before a holiday or weekend
if needed based on the weather forecast.
IV. Soil stockpiles shall be stabilized from erosion, protected with sediment
trapping measures, and, where possible, be located away from storm drain
inlets, waterways, and drainage channels.
6- Protect Slopes.
I. Design and construct cut and fill slopes in a manner that will minimize
erosion. Applicable practices include, but are not limited to, reducing continuous
length of slope with terracing and diversions, reducing slope steepness, and
roughening slope surfaces (e.g., track walking).
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II. Off-site stormwater (run-on) or groundwater shall be diverted away from
slopes and disturbed areas with interceptor dikes, pipes, and/or swales. Off-site
stormwater should be managed separately from stormwater generated on the
site.
III. At the top of slopes, collect drainage in pipe slope drains or protected
channels to prevent erosion. Temporary pipe slope drains and channels shall
handle the expected peak flow velocity from a six-month, three-hour storm for
the developed condition, referred to as the short duration storm.
IV. Check dams shall be placed at regular intervals within constructed
channels that are cut down a slope.
V. Excavated material shall be placed on the uphill side of trenches, consistent
with safety and space considerations.
7- Protect Drain Inlets.
I. All storm drain inlets made operable during construction shall be protected
so that stormwater runoff does not enter the conveyance system without first
being filtered or treated to remove sediment.
II. Inlet protection devices shall be cleaned or removed and replaced when
sediment has filled one-third of the available storage (unless a different standard
is specified by the product manufacturer).
8- Stabilize Channels and Outlets.
I. All temporary on-site conveyance channels shall be designed, constructed,
and stabilized to prevent erosion from the following expected peak flows:
II. Channels shall handle the expected peak flow velocity from a six-month,
three-hour storm for the developed condition, referred to as the short duration
storm.
III. Stabilization, including armoring material, adequate to prevent erosion of
outlets, adjacent stream banks, slopes, and downstream reaches shall be
provided at the outlets of all conveyance systems.
9- Control Pollutants.
I. All pollutants, including waste materials and demolition debris, that occur on-
site shall be handled and disposed of in a manner that does not cause
contamination of stormwater.
II. Cover, containment, and protection from vandalism shall be provided for all
chemicals, liquid products, petroleum products, and other materials that have
the potential to pose a threat to human health or the environment. On-site
fueling tanks shall include secondary containment.
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III. Maintenance, fueling, and repair of heavy equipment and vehicles shall be
conducted using spill prevention and control measures. Contaminated surfaces
shall be cleaned immediately following any spill incident.
IV. Wheel wash or tire bath wastewater shall be discharged to a separate on-
site treatment system or to the sanitary sewer with local sewer district approval.
V. Application of fertilizers and pesticides shall be conducted in a manner and
at application rates that will not result in loss of chemical to stormwater runoff.
Manufacturers' label requirements for application rates and procedures shall be
followed.
VI. BMPs shall be used to prevent or treat contamination of stormwater runoff
by pH-modifying sources. These sources include, but are not limited to: bulk
cement, cement kiln dust, fly ash, new concrete washing and curing waters,
waste streams generated from concrete grinding and sawing, exposed
aggregate processes, de-watering concrete vaults, concrete pumping and mixer
washout waters. Responsible parties shall adjust the pH of stormwater if
necessary to prevent violations of water quality standards.
VII. Responsible parties shall obtain written approval from Ecology prior to
using chemical treatment, other than CO2 or dry ice, to adjust pH.
VIII. Responsible parties shall handle and dispose of on-site litter in a manner
that does not cause contamination of stormwater.
IX. Portable restroom facilities shall be provided for construction workers.
Such facilities shall be cleaned and maintained in a manner that will prevent any
spills. If any spills do occur, they shall be cleaned up immediately.
10- Control De-Watering.
I. Foundation, vault, and trench de-watering water, which have similar
characteristics to stormwater runoff at the site, shall be discharged into a
controlled conveyance system prior to discharge to a sediment trap or sediment
pond.
II. Clean, nonturbid de-watering water, such as well-point groundwater, can be
discharged to systems tributary to, or directly into, surface waters of the state, as
specified in Ecology's construction stormwater general permit (November, 2005)
at S9.D.8, provided the de-watering flow does not cause erosion or flooding of
receiving waters. Clean de-watering water should not be routed through
stormwater sediment ponds.
III. Other de-watering disposal options may include:
i. Infiltration;
ii. Transport off-site in a vehicle, such as a vacuum flush truck, for legal
disposal in a manner that does not pollute state waters;
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iii. Ecology-approved on-site chemical treatment or other suitable treatment
technologies;
iv. Sanitary sewer discharge with local sewer district approval, if there is no
other option; or
v. Use of a sedimentation bag with outfall to a ditch or swale for small volumes
of localized de-watering.
IV. Highly turbid or contaminated de-watering water shall be handled
separately from stormwater.
11- Maintain BMPs.
I. All temporary and permanent erosion and sediment control BMPs shall be
maintained and repaired as needed to assure continued performance of their
intended function in accordance with BMP specifications.
II. All temporary erosion and sediment control BMPs shall be removed within
thirty days after final site stabilization is achieved or after the temporary BMPs
are no longer needed.
12- Manage the Project.
I. Development projects shall be phased to the maximum degree practicable
and shall take into account seasonal work limitations.
b) Inspection and Monitoring.
1. All BMPs shall be inspected, maintained, and repaired as needed to assure
continued performance of their intended function. The SWPPP shall identify an
inspection and maintenance schedule for the BMPs contained in the SWPPP.
Specific BMP inspection and maintenance guidance is contained in the latest version
of the Stormwater Management Manual for Eastern Washington, other Ecology-
approved stormwater manuals, or approved local equivalent.
(3) Maintenance of the Construction SWPPP. The construction SWPPP shall be retained on-
site or within reasonable access to the site. The construction SWPPP shall be modified
whenever there is a significant change in the design, construction, operation, or maintenance of
any BMP.
(4) Construction SWPPP—Map Contents and Requirements.
a) The SWPPP shall also include a vicinity map or general location map (e.g., USGS
Quadrangle map, a portion of a county or city map, or other appropriate map) with enough
detail to identify the location of the construction site and receiving waters within one mile
of the site.
b) The SWPPP shall also include a legible site map (or maps) showing the entire
construction site. The following features shall be identified, unless not applicable due to
site conditions:
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1. The direction of north, property lines, and existing structures and roads;
2. Cut and fill slopes indicating the top and bottom of slope catch lines;
3. Approximate slopes, contours, and direction of stormwater flow before and after
major grading activities;
4. Areas of soil disturbance and areas that will not be disturbed;
5. Locations of structural and nonstructural controls (BMPs) identified in the
SWPPP;
6. Locations of off-site material, stockpiles, waste storage, borrow areas, and
vehicle/equipment storage areas;
7. Locations of all surface water bodies, including wetlands;
8. Locations where stormwater or nonstormwater discharges off-site and/or to a
surface water body, including wetlands;
9. Location of water quality sampling station(s), if sampling is required by state or
local permitting authority; and
10. Areas where final stabilization has been accomplished and no further
construction-phase requirements apply. (Ord. 2010-07 § 1 (part), 2010).
Section 5. This ordinance shall be in full force and effect 30 days after its passage,
approval, and publication as provided by law and by the City Charter.
PASSED BY THE CITY COUNCIL, signed and approved this 2nd day of October, 2018.
ATTEST: athy Co ey, a r
J✓
SonykC ar Tee, City Clerk,,,- „„
Publication Date: October 5, 201.8; ' s
Effective Date: November 4, 2018
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5l
BUSINESS OF THE CITY COUNCIL
YAKIMA, WASHINGTON
AGENDA STATEMENT
Item No. 10.
For Meeting of: October 2, 2018
ITEM TITLE: Ordinance amending the City of Yakima Municipal Code Chapter
7.82 Construction Stormwater Runoff
SUBMITTED BY: Scott Schafer, Director of Public Works
Mike Price, Wastewater/Stormwater Division Manager 249-6815
SUMMARY EXPLANATION:
The City of Yakima (City) is regulated by the Department of Ecology for stormwater management
in accordance with its issued Eastern Washington Phase I I Municipal Stormwater National
Pollutant Discharge Elimination System General Permit#WAR046013.
The City's Stormwater Division is requesting that Yakima Municipal Code (YMC) 7.82
Construction Stormwater Runoff be amended for the following:
• Amend YMC 7.82.020 and 7.82.100 to define and allow the use of Low Impact
Development (LID)techniques
• Amend YMC 7.82.090 to require City review of Stormwater Pollution Prevention Plans for
projects one acre or larger
• Amend YMC 7.82.130 to require proper handling of on-site litter and waste
Codifying the amendments to Section 7.82.020, Section 7.82.100, Section 7.82.090 and
Section 7.82.130 completes an important compliance requirement of the City's permit with the
Department of Ecology.
ITEM BUDGETED: NA
STRATEGIC PRIORITY: NA
APPROVED FOR
SUBMITTAL: City Manager
2
STAFF RECOMMENDATION:
Pass Ordinance
BOARD/COMMITTEE RECOMMENDATION:
ATTACHMENTS:
Description Upload Date Type
D Ordinance YMC 7.82 8/27/2018 Ordinance
D YMC 7.82 Redline 8/30/2018 Backup Material