Centralia Surface-Storm Water Management Plan2021 Stormwater Management Program | City of Centralia, Washington
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2021 Stormwater
Management Program
2021 Stormwater Management Program | City of Centralia, Washington
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Introduction
The National Pollutant Discharge Elimination System (NPDES) permits address water pollution
from point sources into surface waters such as rivers, lakes, and streams. The U.S. Environmental
Protection Agency (EPA) gave Washington State Department of Ecology (Ecology) the authority to
write and issue the NPDES permit in Washington State. The Western Washington Phase II Municipal
Stormwater Permit (Permit) was first issued by Ecology in 2007.
The City of Centralia Municipal Separate Storm Sewer System (MS4) is regulated by the Permit. The
Permit was reissued on July 1, 2019 and became effective August 1, 2019. The new Permit cycle is
from August 1, 2019 to July 1, 2024. The City of Centralia (City) will continue to implement the current
program and include new Permit requirements as they come into effect.
The Stormwater Management Program (SWMP) is required per Section S5 of the Permit. The SWMP
is organized per the program components listed in S5.C. The SWMP is updated annually and submitted
to Ecology by March 31st of each year. The SWMP consist of the following; Components, Current
Activities and Planned Activities:
• S5.C.1 Stormwater Planning
• S5.C.2 Public Education and Outreach
• S5.C.3 Public Involvement and Participation
• S5.C.4 MS4 Mapping and Documentation
• S5.C.5 Illicit Discharge Detection and Elimination
• S5.C.6 Controlling Runoff from New Development, Redevelopment, and Construction Sites
• S5.C.7 Operations and Maintenance
• S5.C.8 Source Control Program for Existing Development
The SWMP is designed to protect water quality by reducing the discharge of pollutants from the
regulated small MS4 to the maximum extent practicable (MEP) and meet state all known, available,
and reasonable methods of prevention, control and treatment (AKART) requirements, and protect
water quality.
The City has an ongoing program for gathering, tracking, maintaining and using information to
evaluate the SWMP development, implementation, and permit compliance, and to set priorities.
The SWMP is a planning and implementation document. The program has three separate objectives
depending on the intended audience:
• Ecology – Provide written documentation on how the City will meet the Permit requirements
for the SWMP.
• The Public – Solicit input and build local support for the City’s SWMP.
• City Staff and Officials – Build support and understanding for the SWMP.
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S5.C.1 Stormwater Planning
Centralia, Washington, is located on I-5 midway
between Seattle and Portland, in Lewis
County. The City of Centralia is located at the
confluences of Salzer Creek, China Creek, the
Skookumchuck River, and the Chehalis River.
Additional secondary creeks, such as Coffee
Creek and Scammon Creek, and a relatively flat
topography make Centralia a unique city with a
watershed that is not easily delineated. The
Stormwater Planning program is to inform and
assist in the development of policies and strategies
as water quality management tools to protect
receiving waters.
PERMIT REQUIREMENTS (S5.C.1):
A. Convene an inter-disciplinary team to inform and
assist in the development, progress, and
influence of this program, by August 1, 2020.
B. Coordination with long-range plan updates.
• Describe how stormwater management
needs and protection/improvement of
receiving water health are (or are not)
informing the planning update processes and
influencing policies and implementation
strategies. The report shall describe the water
quality and watershed protection policies,
strategies, codes, and other measures
intended to protect and improve local
receiving water health through planning, or
taking into account stormwater management
needs or limitations.
• Respond to questions in Annual Report,
describe how anticipated stormwater impacts
on water quality were addressed, if at all,
during 2013-2019 permit term, on or before
March 31, 2021.
• Respond to questions in Annual Report,
describe how water quality is being
addressed, if at all, during this permit term, on
or before January 1, 2023.
C. Low impact development code-related
requirements.
• Continue to require LID Principles and LID
BMPs when updating, revising, and
developing new local development-related
codes, rules, standards, or other enforceable
documents, as needed.
• Annually, assess and document any newly
identified administrative or regulatory
barriers to implementation of LID Principles
or LID BMPs since local codes were updated in
accordance with the 2013 Permit, and the
measures developed to address the barriers.
If applicable, the report shall describe
mechanisms adopted to encourage or require
implementation of LID principles or LID BMPs.
D. Stormwater Management Action Planning:
Receiving Water Assessment:
• Document and assess existing information
related to the local receiving waters and
contributing area conditions to identify which
receiving waters are most likely to benefit
from stormwater management planning.
• By March 31, 2022, submit a watershed
inventory and include a brief description of
the relative conditions of the receiving waters
and the contributing areas. Indicate which
receiving waters will be included in the
prioritization process. Include a map of the
delineated basins with references to the
watershed inventory table.
• Identify which basins are expected to have a
relatively low Stormwater Management
Influence for SMAP. Basins having relatively
low expected Stormwater Management
Influence for SMAP do not need to be
included in the prioritization process.
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Receiving Water Prioritization:
• Develop and implement a prioritization
method and process to determine which
receiving waters will receive the most benefit
from implementation of stormwater facility
retrofits, tailored implementation of SWMP
actions, and other land/development
management actions (different than the
existing, new, and redevelopment
requirements). Document the prioritized and
ranked list of receiving waters no later than
June 30, 2022.
• Document the priority ranking process used
to identify high priority receiving waters. May
reference existing local watershed
management plan(s) as source(s) of
information or rationale for the prioritization.
• The ranking process shall include the
identification of high priority catchment
area(s) for focus of the SMAP.
Stormwater Management Action Plan (SMAP):
No later than March 31, 2023, develop a SMAP
for at least one high priority catchment area that
identifies all of the following:
• A description of the stormwater facility
retrofits needed for the area, including the
BMP types and preferred locations.
• Land management/development strategies
and/or actions identified for water quality
management.
• Targeted, enhanced, or customized
implementation of stormwater management
actions related to permit sections within S5,
including: IDDE field screening, Prioritization
of Source Control inspections, O&M
inspections or enhanced maintenance, Public
Education and Outreach behavior change
programs. Identified actions shall support
other specifically identified stormwater
management strategies and actions for the
basin overall, or for the catchment area in
particular.
• If applicable, identification of changes needed
to local long-range plans, to address SMAP
priorities.
• A proposed implementation schedule and
budget sources for: short-term actions
(accomplished within six years), long-term
actions (accomplished within seven to twenty
years).
• A process and schedule to provide future
assessment and feedback to improve the
planning process and implementation of
procedures or projects.
CURRENT ACTIVITIES (S5.C.1):
The City will continue to require LID Principles and
LID BMPs in developments. The City’s Stormwater
Building Designs and Development Guidelines
includes LID BMP’s in Chapter 9.
PLANNED ACTIVITIES (S5.C.1):
The City plans to create a team of individuals from
various departments to collaborate in the
stormwater planning process. The core team
members will include the Public Works Director,
City Engineer, Community Development Assistant
Director and Stormwater/Streets Technician. As
needed, other departments may get involved. The
core team members shall meet quarterly to discuss
stormwater planning.
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S5.C.2 Public Education & Outreach
The City implemented an education and outreach
program for the area served by the MS4. The
targeted audience is the public; which includes
schools, contractors, developers, homeowners,
material suppliers, and business owners (both
public and private). The program is designed to
educate the targeted audience on the stormwater
problem and provide specific actions they can
follow to minimize the problem.
PERMIT REQUIREMENTS (S5.C.2):
Implement an education and outreach program for
the area served by the MS4. The program shall be
based on local water quality information and target
audience characteristics to identify high priority
target audiences, subject areas, and/or BMPs.
A. General Awareness:
• General Public (including overburden
communities, or school age children), or
Businesses (including home-based and mobile
businesses). Subject areas:
1) General impacts of stormwater on surface
waters. Including impacts from impervious
surfaces.
2) Low impact development (LID) principles
and LID BMPs.
• Engineers, Contractors, Developers, and
Land-use Planners. Subject areas:
1) Technical standards for stormwater site
and erosion control plans.
2) LID principles and LID BMPs.
3) Stormwater treatment and flow control
BMPs/facilities.
• Provide subject area information to the target
audience on an ongoing or strategic schedule.
B. Behavior Change:
• Residents, Landscapers, Property/Owners,
Developers, School age children, or
Businesses (including home-based or mobile
businesses)
BMPs:
1) Use and storage of: pesticides, fertilizers,
and/or other household chemicals.
2) Use and storage of: automotive
chemicals, hazardous cleaning supplies,
carwash soaps, and/or other hazardous
materials.
3) Prevention of illicit discharges.
4) Yard care techniques protective of water
quality.
5) Carpet cleaning.
6) Repair and maintenance BMPs for:
vehicles, equipment, and/or
home/building.
7) Pet waste management and disposal.
8) LID Principles and LID BMPs.
9) Stormwater facility maintenance, include
LID facilities.
10) Dumpster and trash compactor
maintenance.
11) Litter and debris prevention.
12) Sediment and erosion control.
13) Source Control BMPs.
14) Locally-important, municipal stormwater-
related subject area.
• Conduct Evaluation of Effectiveness: No later
than July 1, 2020, evaluate the effectiveness
of an ongoing behavior change campaign.
• By February 1, 2021, follow social marketing
practices and methods, similar to community-
based social marketing to develop a campaign
that is tailored to the community, including
development of a program evaluation plan.
1) Develop a strategy and schedule to more
effectively implement the existing
campaign; or
2) Develop a strategy and schedule to
expand the existing campaign to a new
target audience or BMPs; or
3) Develop a strategy and schedule for a
new target audience and BMP behavior
change campaign.
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• No later than April 1, 2021, begin to
implement the strategy developed.
• No later than March 31, 2024, evaluate and
report on:
1) The changes in understanding and
adoption of targeted behaviors resulting
from the implementation of the strategy;
and
2) Any planned or recommended changes to
the campaign in order to be more
effective; describe the strategies and
process to achieve the results.
• Use results of the evaluation to continue to
direct effective methods and implementation
of the ongoing behavior change program.
C. Stewardship:
• Provide and advertise stewardship
opportunities and/or partner with existing
organizations (including non-permittees) to
encourage residents to participate in
activities or events planned and organized
within the community.
CURRENT ACTIVITIES (S5.C.2):
General Awareness:
• Maintain Stormwater website
• Pet waste management and disposal
• Proper disposal of household hazardous waste
• Prohibit illegal dumping and littering in
stormwater facilities
• Illicit discharge hotline flyer
• Car wash program
• Rain Garden Demonstration
• Stream Team
• Leaf disposal program
Behavior Change:
Pet waste is an ongoing issue. The City has
developed a behavior change plan to encourage
higher rates of dog owners picking up and properly
disposing of pet waste. This program will be set up
on the Discovery Trail (off Goodrich Road by the
Waste Water Treatment Plant), and at Borst Park.
Signage and a survey will be posted at every dog
baggie station to inform and promote the pet waste
program.
Stewardship:
• Stream Team Meetings
• China Creek Clean-up
• Storm Drain Marker Program
• Pet Waste Management
PLANNED ACTIVITIES (S5.C.2):
The City will continue to implement the Current
Activities and the activities below.
General Awareness:
• Car Wash Kit campaign and leaf bin campaign
Behavior Change:
• Pet waste behavioral change program
Stewardship:
• China Creek clean-up with the Centralia Stream
Team
• Tree planting along Chehalis River on Discovery
Trail.
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C5.C.3 Public Involvement & Participation
Public involvement and participation is important to creating an effective stormwater management program.
PERMIT REQUIREMENTS (S5.C.3):
A. Create opportunities for the public, including overburdened communities, to participate in the decision-
making processes involving the development, implementing and update of the SMAP and SWAP.
B. City shall post the SWMP Plan and the annual report on the website, no later than May 31st of each year. All
other submittals shall be available to the public upon request.
CURRENT ACTIVITIES (S5.C.3):
The City utilizes various communication mediums to convey involvement and participation events to the public,
such as: social media, City website, newspaper articles and other web-based channels. The City post the latest
annual report and Stormwater Management Program (SWMP) on the website by March 31st each year. The
public can submit comments on the SWMP from the City’s website.
PLANNED ACTIVITIES (S5.C.3):
The City will continue to implement the Current Activities and explore other means of public involvement
opportunities.
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S5.C.4 MS4 Mapping and Documentation
The City has an ongoing program for mapping and
documentation of the MS4.
PERMIT REQUIREMENTS (S5.C.4):
A. Ongoing Mapping of MS4:
• Known MS4 outfalls and discharge points.
• Receiving waters, other than groundwater.
• Public stormwater treatment and flow control
BMPs/facilities
• Geographic areas that do not discharge
stormwater to the surface waters.
• Tributary conveyance to all known outfalls
and discharge points with a 24-inch diameter
or larger, or an equivalent cross-sectional
area for non-pipe system (tributary
conveyance type, material, size, associated
drainage areas, land use).
• Connections between the MS4 owned or
operated by the other municipalities or public
entities.
• All connections to the MS4 authorized or
allowed by the City after February 16, 2007.
B. New Mapping requirements:
• No later than January 1, 2020, begin to collect
size and material for all known MS4 outfalls
during normal course of business and update
records.
• No later than August 1, 2023, complete
mapping of all know connections from the
MS4 to a privately owned stormwater system.
C. No later than August 1, 2021, the required
format for mapping is electronic with fully
described mapping standards.
D. Upon request, make maps available to Ecology.
E. Upon request, and to the extent appropriate,
provide mapping information to federally
recognized Indian Tribes, municipalities, and
other Permittees. Permit does not preclude the
City from recovering reasonable costs associated
with fulfilling mapping information requests by
federally recognized Indian Tribes, municipalities
and other Permittees.
CURRENT ACTIVITIES (S5.C.4):
The City maintains the MS4 mapping by
incorporating record drawing information from
developments and correcting existing features as
needed. The MS4 mapping updates are performed
in CentralSquare.
PLANNED ACTIVITIES (S5.C.4):
The City will continue to maintain the MS4 mapping.
All known MS4 outfalls (size and material) will be
added/updated to the MS4 mapping.
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S5.C.5 Illicit Discharge and Elimination (IDDE)
Discharges from cities often include wastes and
wastewater from sources other than stormwater.
Illicit discharges are those that enter the public
storm system in two ways, (1) by direct connection
of wastewater piping to storm lines; or (2) through
indirect connections, such as infiltration from
cracked wastewater piping, dumping of illicit
material into storm drains, or accidental spills that
result in wastewater flowing into storm drains.
PERMIT REQUIREMENTS (S5.C.5):
A. The program shall include procedures for
reporting and correcting or removing illicit
connections, spills and other illicit discharges
when they are suspected or identified. The
program shall also include procedures for
addressing pollutants entering the MS4 from an
interconnected, adjoining MS4.
• Illicit connections and illicit discharges must
be identified through, but not limited to: field
screening, inspections, complaints/report,
construction inspections, maintenance
inspections, source control inspections,
and/or monitoring information, as
appropriate.
B. Inform public employees, businesses, and the
general public of hazards associated with illicit
discharges and improper disposal of waste.
C. Implement an ordinance or other regulatory
mechanism to effectively prohibit non-
stormwater, illicit discharges into the MS4 to the
maximum extent allowable under state and
federal law. The ordinance shall include
escalating enforcement procedures and actions.
D. Implement an ongoing program designed to
detect and identify non-stormwater discharges
and illicit discharges and connections into the
MS4.
• Implement a field screening methodology
appropriate to the characteristics of the MS4
and water quality concerns. Complete field
screening for an average of 12% of the MS4
each year. Annually track total percentage of
the MS4 screened beginning August 1, 2019.
• Provide a publicly listed and publicized hotline
or other telephone number for public
reporting of spills and other illicit discharges.
• Ongoing training program for all municipal
field staff on identification of an illicit
discharge and/or connection, and on proper
procedures for reporting and responding to
the illicit discharge and/or connection.
Provide follow-up trainings as needed to
address changes in procedures, techniques,
requirements, or staffing. Document and
maintain records of the trainings provided
and the staff trained.
E. Implement an ongoing program designed to
address illicit discharges, including spills and
illicit connections, into the MS4.
• Procedures for characterizing the nature of,
and potential public or environmental threat
posed by, any illicit discharges found by or
reported to the City. Procedures shall address
the evaluation of whether the discharge must
be immediately contained and steps to be
taken for containment of the discharge.
• Procedures for tracing the source of an illicit
discharge.
• Procedures for eliminating the discharge,
including notification of appropriate
authorities and property owners.
F. Ensure municipal stuff who are responsible for
identification, investigation, termination,
cleanup, and reporting of illicit discharges,
including spills, and illicit connections are trained
to conduct these activities. Provide follow-up
trainings as needed to address changes in
procedures, techniques, requirements, or
staffing. Document and maintain records of the
training provided and the staff trained.
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G. Recordkeeping: Track and maintain records of
the activities conducted. In the Annual Report,
submit data for the illicit discharges, spills and
illicit connections including those that were
found by, reported to, or investigated by the City
during the previous calendar year.
CURRENT ACTIVITIES (S5.C.5):
The City’s Illicit Detection and Discharge Elimination
Ordinance (CMC 15.37) incorporates the various
aspects of the Permit requirements.
The ongoing IDDE program includes procedures for
addressing illicit discharges, tracing the source and
eliminating the discharge.
The IDDE program continues to educate the public
on the harmfulness of improper disposal of waste.
Our website contains report a spill and the 24/7
hotline number.
The City maintains a hotline and mobile application
(Centralia Hotline 24/7) that allows citizens to
report illicit discharges/connections.
Calls/complaints are routed to the appropriate
staff(s).
Outfall inspections is the chosen method for field
screening assessment. At a minimum, 12% of the
MS4 outfalls are inspected yearly during the dry
season.
Field staff are trained when first hired and annually
thereafter. Records of staff training is documented.
All inspections, investigation, illicit discharges and
spill-related activities are tracked on spreadsheets
and reported on the Ecology website, per Permit
requirements.
PLANNED ACTIVITIES (S5.C.5):
The City will continue to implement the Current
Activities.
The City will continue to track the total percentage
of MS4 screened annually.
The City will complete IDDE reporting data in
accordance to the format provided in Appendix 12.
The IDDE reporting data will be submitted with the
Annual Report.
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S5.C.6 Controlling Runoff from Development &
Construction
The City will implement, and enforce a program to
reduce pollutants in stormwater runoff from new
development, redevelopment, and construction site
activities. The program shall apply to private and
public development, including transportation
projects.
PERMIT REQUIREMENTS (S5.C.6):
A. Implement an ordinance or other enforceable
mechanism that addresses runoff from new
development, redevelopment, and construction
site projects.
• Adopt and make effective a local program, no
later than June 30, 2022, that meets the
requirements of Section B [S5.C.6.b(i) through
(iii)], below, and shall apply to applications
submitted.
1) On or after July 1, 2022.
2) Prior to January 1, 2017, that have not
started construction by January 1, 2022.
3) Prior to July 1, 2022, that have not started
construction by July 1, 2027.
B. The ordinance shall include, at a minimum:
• The Minimum Requirements, thresholds, and
definitions in Appendix 1, or the 2013
Appendix 1 amended to include the changes
identified in Appendix 10, or Phase I program
approved by Ecology and amended to include
Appendix 10, for new development,
redevelopment, and construction sites. Such
local requirements and thresholds shall
provide equal protection of receiving waters
and equal levels of pollutant control to those
provide in Appendix 1.
• The local requirements shall include the
following requirements, limitations, and
criteria that, when used to implement the
minimum requirements in Appendix 1 will
protect water quality, reduce the discharge of
pollutants to the MEP, and satisfy the State
requirements under chapter 90.48 RCW to
apply AKART prior to discharge:
1) Site planning requirements
2) BMP selection criteria
3) BMP design criteria
4) BMP infeasibility criteria
5) LID competing needs criteria
6) BMP limitations
• The legal authority, through the approval
process for new development and
redevelopment, to inspect and enforce
maintenance standards for private
stormwater facilities that discharge to the
MS4.
C. The program shall include a permitting process
with plan review, inspection and enforcement
capability to meet the standards listed below, for
both private and public projects, using qualified
personnel. At a minimum, the program shall be
applied to all sites that that meet the minimum
thresholds adopted pursuant to Section B
[S5.C.6.b.i].
• Review all stormwater site plans for proposed
development activities.
• Inspect, prior to clearing and construction, all
known development sites that have a high
potential for sediment transport.
• Inspect all permitted development sites
during construction to verify proper
installation and maintenance of required
erosion and sediment controls. Enforce as
necessary based on the inspection.
• Inspect all stormwater treatment and flow
control BMPs/facilities, and catch basins, in
new residential developments every six
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months, until 90% of the lots are constructed
(or when construction has stopped and the
site is fully stabilized), to identify
maintenance needs and enforce compliance
with maintenance standards as needed.
• Inspect all permitted development sites upon
completion of construction and prior to final
approval or occupancy to ensure proper
installation of permanent stormwater
controls. Verify that a maintenance plan is
competed and responsibility for maintenance
is assigned. Enforce as necessary based on the
inspection.
• Compliance by achieving at least 80% of
scheduled inspections.
• Include a procedure for keeping records of
inspections and enforcement actions by staff,
including inspection reports, warning letters,
notices of violations, and other enforcement
records. Records of maintenance inspections
and maintenance activities shall be
maintained.
• An enforcement strategy shall be developed
and implemented to respond to issues of non-
compliance.
D. Make available the link to the electronic
Construction Stormwater General Permit Notice
of Intent (NOI) form and Industrial Stormwater
General Permit NOI form. Continue to enforce
local ordinances controlling runoff site that are
also covered by stormwater permits issued by
Ecology.
E. Ensure that municipal staff whose primary job
duties are implementing the program to control
stormwater runoff from new development,
redevelopment, and construction sites, including
permitting, plan review, construction site
inspections, and enforcement, are trained to
conduct these activities. Follow-up training must
be provided as needed to address changes in
procedures, techniques or staffing. Document
and maintain records of the training provided
and the staff trained.
CURRENT ACTIVITIES (S5.C.6):
The City has an ongoing program for the permit
process with plan review, inspection and
enforcement capabilities. All inspections are
documented.
The City’s Stormwater Control Ordinance (CMC
15.37) was adopted in 2009 and revised 2021, and
incorporates the various Permit requirements.
The City adopted (CMC 15.37) the latest Stormwater
Management Manual for Western Washington
(SWMMWW) to help control runoff from
developments and construction sites. The
requirements, limitations, and criteria of the
SWMMWW will protect water quality, reduce the
discharge of pollutants to the MEP, and satisfy State
AKART.
All field staff are trained in erosion control
inspection and has a Certified Erosion and Sediment
Control Lead (CESCL) Certification.
The City continues to refine: tracking mechanism for
inspections and enforcements, development
inspection procedures and site plan review
standards.
PLANNED ACTIVITIES (S5.C.6):
The City will continue to implement the Current
Activities.
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S5.C.7 Operations & Maintenance
The City developed and implemented an Operations
and Maintenance (O&M) program to regulate and
conduct maintenance activities to prevent or
reduce stormwater impacts.
PERMIT REQUIREMENTS (S5.C.7):
A. Implement maintenance standards that are as
protective, or more protective, of facility
function than those specified in the SWMMWW.
Maintenance standards shall be developed for
facilities that does not have maintenance
standards. No later than June 30, 2022,
maintenance standards shall be updated to meet
Permit requirements.
• Unless there are circumstances beyond the
City’s control, when an inspection identifies
an exceedance of the maintenance standards,
maintenance shall be performed:
1. Within 1 year for typical maintenance of
facilities, except catch basins.
2. Within 6 months for catch basins.
3. Within 2 years for maintenance that
requires capital construction of less than
$25,000.
• For each exceedance of the required
timeframe, the Permittee shall document the
circumstances and how they were beyond
their control.
B. Implement a stormwater facility maintenance
program for facilities regulated by the City.
• Implementation of an ordinance or other
enforceable mechanism.
• Annual inspections of all private stormwater
treatment and flow control BMPs/facilities
that discharges to the MS4 and were
permitted by the City, including those
permitted in accordance with requirements
adopted pursuant to the 2007-2019 Permits.
• Compliance with the inspection requirements
by achieving at least 80% of required
inspections.
• The program shall include a procedure for
keeping records, warning letters, notices of
violations, and other enforcement records.
Records of maintenance inspections and
maintenance activities shall be maintained.
C. Implement a stormwater facility maintenance
program for facilities owned or operated by the
City.
• Annual inspection of all municipally owned or
operated permanent stormwater treatment
and flow control facilities, and taking
appropriate maintenance actions.
• Spot checks of potentially damaged
permanent treatment and flow control
facilities after major storm events. Conduct
repairs or take appropriate maintenance
action in accordance with maintenance
standards.
• Inspect all catch basins and inlets owned or
operated by the City every two years. Clean
catch basins, if the inspection indicates
cleaning is needed to comply with
maintenance standards established in the
SWMMWW.
• Compliance by achieving 95% of required
inspections.
D. No later than December 31, 2022, implement
and document maintenance practices, policies,
and procedures to reduce stormwater impacts
associated with runoff from all lands owned or
maintained by the City, and road maintenance
activities under the functional control of the City.
Lands owned or maintained by the City include,
but are not limited to: streets, parking lots,
roads, highways, buildings, parks, open spaces,
road right-of-ways, maintenance yards, and
stormwater treatment and flow control
BMPs/facilities.
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Program shall address the following activities:
• Pipe cleaning
• Clean culverts that convey stormwater in
ditch systems
• Ditch maintenance
• Street cleaning
• Road repair and resurfacing, including
pavement grinding
• Snow and ice control
• Utility installation
• Pavement striping maintenance
• Maintaining roadside areas, including
vegetation management
• Dust control
• Application of fertilizers, pesticides, and
herbicides
• Sediment and erosion control
• Landscape maintenance and vegetation
disposal
• Trash and pet waste management
• Building exterior cleaning and maintenance
E. Implement an on-going training program for staff
whose primary construction, operations, or
maintenance job functions may impact
stormwater quality. Follow-up training shall be
provided as needed to address changes in
procedures, techniques, requirements, or
staffing. Document and maintain records of
training provided and staff trained.
F. Implementation of a Stormwater Pollution
Prevention Plan (SWPPP) for all heavy equipment
maintenance or storage yards and material
storage facilities owned or operated by the City.
Update SWPPP no later than December 31, 2022,
to include the following information:
• A detailed description of the operational and
structural BMPs in use at the facility and a
schedule for implementation of additional
BMPs when needed.
• Perform annual inspections of the facility,
including visual observations of discharges, to
evaluate effectiveness of the BMPs, identify
maintenance needs, and determine if
additional or different BMPs are needed. The
results of the inspections must be
documented in an inspection report or check
list.
• An inventory of the materials and equipment
stored on-site, and the activities conducted at
the facility which may be exposed to
precipitation or runoff and could result in
stormwater pollution.
• A site map showing the facility’s stormwater
drainage, discharge points, and areas of
potential pollutant exposure.
• A plan for preventing and responding to spills
at the facility which would result in an illicit
discharge.
G. Maintain records of inspections and
maintenance or repair activities conducted by
the City and private property owners.
CURRENT ACTIVITIES (S5.C.7):
The Streets maintenance crew has an ongoing
program to inspect and clean catch basins, and to
inspect and maintain public stormwater facilities.
Street sweeping is done on a regular basis. There is
a list of ‘Hot Spots’ that are checked after every
major storm event.
In 2015, the City hired/created a Stormwater
Technician position that is dedicated to stormwater
related activities.
The City has an ongoing program to inspect private
stormwater facilities and coordinate with private
owners for maintenance.
The City has an ongoing training program for
employees, who encounter stormwater on a regular
basis, to learn the importance of protecting water
quality.
A SWPPP (Stormwater Pollution and Prevention
Plan) was developed for the City maintenance yards
and heavy equipment yards. This is a dynamic
document, contents are updated as needed.
PLANNED ACTIVITIES (S5.C.7):
The City will continue to implement the Current
Activities.
2021 Stormwater Management Program | City of Centralia, Washington
Page 15 | 17
S5.C.8 Source Control Program for Existing
Development
The City shall implement a program to prevent and
reduce pollutants in runoff from publicly and
privately owned institutional, commercial and
industrial sites that discharge to the MS4.
PERMIT REQUIREMENTS (S5.C.8):
A. No later than August 1, 2022, adopt and make
effective an ordinance(s), or other enforceable
documents, requiring the application of source
control BMPs for pollutants generating sources
associated with existing land uses and activities.
• Applicable operational source control BMPs
shall be required for all pollutant generating
sources. Structural source control BMPs, or
treatment BMPs/facilities, or both, shall be
required for pollutant generating sources if
operational source control BMPs do not
prevent illicit discharges or violations of
surface water, groundwater, or sediment
management standards because of
inadequate stormwater control.
B. No later than August 1, 2022, establish an
inventory that identifies publicly and privately
owned institutional, commercial, and industrial
sites which have the potential to generate
pollutants to the MS4. The inventory shall
include: businesses, home-based businesses and
multi-family sites.
C. No later than January 1, 2023, implement an
inspection program for sites identified in the
inventory.
• All identified sites with a business address
shall be provided information about activities
that may generate pollutants and the source
control requirements applicable to those
activities. This information shall be provided
by mail, telephone, electronic
communications, or in person. This
information may be provided all at one time
or spread out over the Permit term to allow
for tailoring and distribution of the
information during site inspections.
• Annually, complete the number of inspections
equal to 20% of the businesses and/or sites
listed in their source control inventory to
assess BMP effectiveness and compliance
with source control requirements.
• Inspect 100% of sites identified through
credible complaints.
D. No later than January 1, 2023, implement a
progressive enforcement policy that requires
sites to comply with stormwater requirements
within a reasonable time period.
E. Ensure municipal staff who are responsible for
implementing the source control program are
trained to conduct these activities. The ongoing
training program shall cover the legal authority
for source control, source control BMPs and their
proper application, inspection protocols, lessons
learned, typical cases, and enforcement
procedures. Provide follow-up training as
needed to address changes in procedures,
techniques, requirements, or staff. Document
and maintain records of the training provided
and the staff trained.
CURRENT ACTIVITIES (S5.C.8):
Working on adopting current ordinances to become
compliant before August 1, 2022.
PLANNED ACTIVITIES (S5.C.8):
The City plans to start compiling the inventory of
publicly and privately owned institutional,
commercial, and industrial sites in accordance with
Appendix 8 of the Permit.
2021 Stormwater Management Program | City of Centralia, Washington
Page 16 | 17
S8 Monitoring & Assessment
All Permittees shall provide, in each annual report,
a description of any stormwater monitoring or
stormwater-related studies conducted during the
reporting period. If other stormwater monitoring or
stormwater-related studies were conducted on
behalf of the Permittee during the reporting period,
or if stormwater-related investigations conducted
by other entities were reported during the reporting
period, a brief description of the type of information
gathered or received shall be included in the annual
report.
Permittees are not required to provide descriptions
of any monitoring, studies, or analyses conducted as
part of the Regional Stormwater Monitoring
Program (RSMP) in annual reports. If a Permittee
conducts independent monitoring in accordance
with requirements in [S8.C], annual reporting of
such monitoring must follow the requirements
specified in that section.
2021 Stormwater Management Program | City of Centralia, Washington
Page 17 | 17
S9 Reporting Requirements
A. An annual report is required to be submitted no
later than March 31st of each year of the Permit,
beginning in 2020. The report covers the
reporting period from January 1st through
December 31st unless otherwise specified.
B. The City is required to keep all records related to
the Permit and the SWMP for at least five years.
C. All records related to this permit and the City’s
SWMP shall be available to the public at
reasonable times during business hours. A copy
of the most recent annual report will be provided
to any individual or entity, upon request.
• A reasonable charge may be assessed for
making photocopies of records.
• The City may require reasonable advance
notice of intent to review records related to
this permit.
D. The annual report shall include the following:
• The current Stormwater Management Plan
(SWMP);
• Submittal of the annual report form as
provided by Ecology pursuant to S9.A,
describing the status of implementation of
the requirements of this permit during the
reporting period.
• Attachments to the annual report form
including summaries, descriptions, reports,
and other information as required, or as
applicable, to the requirements of this permit
during the reporting period.
• If applicable, notice that MS4 is relying on
another governmental entity to satisfy any of
the obligation under this permit.
• Certification and signature pursuant to G19.D,
and notification of any changes to
authorization pursuant to G19.C.
• A notification of any annexations,
incorporations or jurisdictional boundary
changes resulting in an increase or decrease
in the Permittee’s geographic area of permit
coverage during the reporting period.
E. No later than March 31st of each year, the new
annual report and the updated SWMP will be
available to the public on the City's webpage at
http://www.cityofcentralia.com/Page.asp?NavI
D=101