Frequently Asked Questions
Preliminary Draft Western Washington Permit Language (2012)
The information on this page is outdated. The municipal stormater permit language referred to in the questions
below has been revised, and the answers may or may not be accurate. This page is maintained for
historical purposes only.
Please visit the the current
permit page for the most up-to-date information.
Click on the questions below to see responses.
Low Impact Development (LID)
Why add LID requirements to the permits?
- LID is a beneficial approach
for managing stormwater runoff which, in turn, helps protect water quality and
stream habitat. Preliminary draft low impact development requirements proposed
for Phase I permittees and Western Washington Phase II permittees stem from
appeals of the 2007 permits to the Pollution Controls Hearing Board (PCHB). The
rulings by the PCHB have led Ecology to develop LID definitions, a performance
standard, and feasibility criteria based on input from an advisory process.
To find out more information regarding the PCHB rulings click here:
What process did Ecology use to develop the Western Washington requirements?
- After the PCHB issued rulings on the 2007 permits, Ecology
used funding from USEPA Region 10 to conduct a review process to develop
recommendations for LID requirements. Part of the review process included
establishing two advisory committees to assist Ecology in developing LID
requirements. A broad range of interests were represented, and the committee
meetings were open to the public. Ecology considered the input and
recommendations from the advisory process when it developed preliminary draft
language for LID requirements. The LID advisory committee meeting summaries,
studies, and references are available along with Ecology’s previous proposals
and public comments at:
Will the LID or monitoring requirements apply to new permittees in 2012?
- Ecology is evaluating a number of cities and county Urban
Growth Areas for coverage under the 2012 Phase II permits. Ecology does not
propose to apply the monitoring requirements under S8.C to new permittees in the
next permit cycle. Ecology has not yet determined whether new permittees should
be subject to the LID requirements during the next permit cycle. Considerations
include the workload for local governments to update stormwater and other
development codes once during this permit cycle, and then again in the following
permit cycle to adopt LID requirements. On the other hand, the jurisdictions may
benefit from a more gradual and incremental approach to managing runoff from new
development, redevelopment and construction sites as they build their stormwater
management programs. In the next permit cycle they will build programs to meet
other requirements, including those for illicit discharge detection and
elimination, public education, municipal operations and maintenance, and public
involvement. Ecology will present its proposal on this issue in the October 2011
formal draft permit.
How is Low Impact Development defined?
- Low Impact Development (LID)
is 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.
What are the substantive changes to the permits for LID?
- The preliminary draft permits
propose at least two and in some cases, three levels of regulatory action by
municipalities: 1) update stormwater and related codes to incorporate new
site-level LID requirements; 2) review and revise land development-related
ordinances, rules, and standards to incorporate LID principles that minimize
impervious surfaces, native vegetation loss, and stormwater runoff in all types
of development situations, where feasible (The intent of the revisions is to
make the new LID requirements the preferred and commonly-used approach for site
development); and 3) conduct hydrologic and water quality analyses to
demonstrate how the municipality will maintain beneficial uses of the waters of
the State in watersheds where the urban growth area will expand or where a
zoning change will increase the total impervious area by five percent or more.
How will the LID requirements apply on tight soils with low infiltration rates?
- Ecology recognizes that each
site, city, and county is unique, and there are conditions that can make some
LID techniques infeasible. In the preliminary draft Ecology is proposing
infeasibility criteria for rain gardens, bioretention facilities, permeable
pavements, and green roofs. If one of these infeasibility criteria applies, then
the applicable LID method would not be required. Often if one LID method is not
appropriate, other LID methods can still be used.
What development projects would be affected by the requirements?
- In Phase I and Phase II
communities, all new development and redevelopment projects resulting in 2,000
square feet, or greater, of new plus replaced hard surface area, or having a
land disturbing activity of 7,000 square feet or greater would be required to
meet the revised Minimum Requirement #5 (MR #5): On-site Stormwater Management.
MR #5 now includes additional proposed requirements for LID based on project
size, project type, and location within or outside the Urban Growth Area (UGA).
Why was the one acre threshold removed from the Phase II permit?
- Ecology’s proposal to reduce the one-acre
threshold is intended to prevent harm to aquatic habitat and water quality from
the cumulative impacts of development on parcels smaller than one acre. If the
one acre threshold were to remain in place in urban areas covered by the Phase
II permit, a significant amount of development would occur without LID on
smaller parcels. In most urban areas, a majority of development projects occur
as infill and on project sites smaller than one acre.
- To evaluate the change this would bring to
Phase II communities, Ecology staff conducted a review of available municipal
codes and enforceable documents in Western Washington Phase II jurisdictions in
February and March of 2011. The review found a total of 73 jurisdictions, or
85%, apply stormwater standards to project sites of less than one acre. A total
of 55 jurisdictions (or 64% of Phase IIs) appear to meet the thresholds in the
Stormwater Management Manual for Western Washington (SWMMWW), while about 22%
apply requirements at a variety of thresholds between the SWMMWW standards and
the one-acre threshold. These results indicate most Phase II jurisdictions
recognize the importance of managing stormwater in urban areas at sites smaller
than one acre.
How would a city or county update development-related ordinances, rules, and standards?
- The preliminary draft permit
directs permittees to conduct and document a process similar to the steps and
range of issues outlined in a document entitled: Integrating LID into Local
Codes: A Guidebook for Local Governments (Puget Sound Partnership, 2011). A
draft of that document is available for review starting June 1, 2011 at
www.psp.wa.gov . Public
workshops to introduce the document and receive comments from interested parties
are scheduled as follows:
- June 7: Tacoma, Center for
Urban Waters; 326 East D. Street
June 13: Poulsbo; The New Poulsbo City Hall, 200 NE Moe Street
June 20: Mount Vernon; Public Utility District #1 of Skagit County, 1415
How would a city or county implement the watershed-scale stormwater planning requirement?
- Under the proposed
requirements, when a city plans an annexation, or the county a UGA expansion, of
80 acres or more in watersheds between 2 square miles and 40 square miles in
size, then the permittee would have to conduct an analysis of impacts to
hydrology and water quality from the proposed expansion. A similar analysis
would be required in watersheds between 2 square miles and 40 square miles for a
city or county taking a land use action such as zoning that increases the total
watershed impervious surface area by more than five percent of the existing
total impervious area of the watershed. The increases for expanded boundaries
and impervious surface areas would be counted from the effective date of the
permit (or the last analysis conducted in that watershed) until cumulative
increases reached the threshold.
- The city, or county, could
reduce the impacts (or avoid the analysis, in some cases) if the proposed land
use change is in an area with vegetated buffers, conservation easements,
requirements for clustering and low impact development BMPs (like pervious
pavement), and other measures that together reduce the impervious surface area.
A city or county could plan ahead and include in the analysis additional areas
of expected future expansion in the same watershed. By conducting an analysis
for a larger area, or the entire watershed, the jurisdiction could reduce
long-term costs and increase certainty of future land use zoning for property
owners and the development community.
- This proposed requirement is
intended to address future land use actions that have an impact on water quality
and hydrology, but is not intended to change land use decisions made in the
past. However, in some cases the analysis may lead a jurisdiction to alter a
past land use decision in order to reduce the impacts and avoid water quality
degradation, so as to proceed with the proposed land use action.
Would watershed-scale stormwater planning requirements apply to construction projects?
- Ecology does not intend this
proposed requirement to apply to individual development projects. However, an
individual project could trigger the analysis if the project included a change
in zoning, or change in other land use regulations, which would allow an
increased impervious surface area beyond five percent of the existing total
impervious area of the watershed. Projects allowed under previous zoning would
not count toward the threshold for watershed-scale analysis. However, the LID
site and subdivision-scale requirements adopted under the permit would apply to
Would watershed-scale planning be required?
- No, the proposed requirement
for watershed-scale stormwater planning does not require permittees to develop a
watershed plan. However, Ecology is proposing triggers for watershed analysis
based on the percent of impervious area or based on an expansion of a city or
UGA boundary by 80 or more acres within watersheds of approximately 2 square
miles to 40 square miles in size.
- The analysis would require an
assessment of the hydrologic and water quality impacts from upstream and upon
areas downstream of the proposed land use action. The assessment would consider
impacts under existing land use regulations in the area outside its
jurisdiction. In some cases, a city or county might have authority over the
entire watershed, but in many cases the watershed extends into another
- The proposed requirement does
not mandate cooperation among jurisdictions to develop a watershed plan, and
expects that measures for limiting harm from development will be based on
actions within the area under the jurisdiction’s authority. Ecology does not
propose to require that jurisdictions cooperate with each other in the analysis,
but encourages such cooperation where it occurs. For example, a county proposal
to increase the unincorporated UGA is often done with agreement of a city, and
together they might undertake an analysis of a watershed that they have
identified as suitable for future urban development.
Will Ecology provide tools, guidance, and examples for watershed-scale stormwater planning?
- Ecology is working with
several jurisdictions on watershed-scale projects to model the hydrologic and
water quality impacts of development. These projects vary in the existing level
of urbanization, watershed size, and the models and methods being applied.
Ecology plans to provide guidance, templates, and examples from these projects.
We will also look for grant funding for additional projects, and for
opportunities to integrate TMDL (Total Maximum Daily Load) studies and water
cleanup plans to advance and support permittee efforts.
Should Eastern Washington expect to
have similar LID requirements?
- Eastern Washington has unique
climate conditions, geology, soils, and stormwater management approaches that
differ greatly from those in western Washington. Therefore, LID requirements and
approaches will be different from those proposed in the draft Phase I and WWA
Phase II permits. Many Eastern Washington permittees are already taking
advantage of LID principles such as requiring all stormwater to be infiltrated
on-site and full dispersion BMPs. Ecology is initiating a series of meetings
with permittees and interested parties to develop recommendations for LID
requirements for eastern Washington.
What process will Ecology use to
develop the Eastern Washington requirements?
- Ecology will rely on input
from discussions with permittees and others in eastern Washington during summer
2011 to develop draft requirements for LID for the October 2011 formal draft
permit. The discussions may consider steps to advance LID such as evaluation of
a hydrologic performance standard with feasibility criteria, a list of
acceptable BMPs, and a path forward both inside and outside of the permit
structure to develop an LID manual, guidance, and research regarding the
performance of LID BMPs in soils and precipitation patterns of different
sub-regions of the eastern Washington landscape. Ecology invites comments during
this informal review period to suggest topics for discussion.
What jurisdictions are affected by
the proposed stormwater monitoring requirements?
- Ecology is proposing
preliminary draft permit language for monitoring requirements in three areas of
Puget Sound permittees
including those in Clallam, Thurston, Kitsap, Pierce, King, Snohomish,
Island, Skagit, and Whatcom counties.
permittees include those in Clark, Cowlitz, Lewis, and Grays Harbor
permittees include those in Asotin, Benton, Chelan, Douglas, Franklin,
Grant, Kittitas, Spokane, Walla Walla, Whitman, and Yakima Counties.
- Western Washington permittees
include those in Puget Sound and those in southwest Washington. In Puget Sound,
the current municipal stormwater permits cover 5 Phase I and 76 Phase II cities
and counties and the Ports of Tacoma and Seattle. In southwest Washington, the
current permits cover 1 Phase I county and 9 Phase II cities and counties. In
eastern Washington, the current permit covers 24 Phase II cities and counties.
- The Washington State
Department of Transportation would be affected when Ecology reissues its permit,
which is on a different five-year cycle.
What are the proposed stormwater
- The preliminary draft
language proposes a collaborative, regional approach to stormwater monitoring
throughout western Washington. The proposed structure includes a coordinated
monitoring program based on shared costs among permittees, with Ecology acting
as the service provider to administer contracts. Permittees would participate in
a formal oversight committee. This proposed approach removes specific monitoring
requirements from the permits and relieves individual permittees of the
obligation to individually conduct monitoring activities.
- In southwest Washington,
permittees and others are working to develop an alternate proposal for
monitoring water bodies that receive stormwater discharges. For eastern
Washington, Ecology proposes a stakeholder process to develop a regional
monitoring program and a framework to administer it. The preliminary draft
language includes default proposals for monitoring in southwest and eastern
Washington. However, Ecology anticipates that the stakeholder processes will
produce appropriate proposals for these regions’ unique characteristics.
How did Ecology come up with the
proposed stormwater monitoring requirements?
- The overall approach for
western Washington was developed in a two-year stakeholder process involving
federal, tribal, state and local government, business, environmental,
agriculture and research interests at the request of the Puget Sound Partnership
and Ecology. The Stormwater Work Group (SWG) recommended a comprehensive
monitoring approach for the next NPDES municipal stormwater permits in Puget
Sound. Ecology is proposing to expand some, but not all, of the Puget Sound
recommendations throughout western Washington. Ecology is proposing a similar
process be used to develop a monitoring program of receiving waters for
southwest Washington and an overall monitoring program for eastern Washington.
What are the implications for local
- All local governments in
Washington will benefit from the information generated by regional monitoring.
In western Washington, Phase I and II permittees would be required to equitably
pay into a collective fund for the regional monitoring program instead of being
required to conduct individual jurisdiction monitoring programs. This regional
monitoring program would not replace individual jurisdiction sampling for
illicit discharge detection activities, or sampling conducted to further the
goals of an applicable TMDL or other local water quality investigation.
Permittees and others with monitoring capacity would have the opportunity to
receive funds to conduct parts of the regional monitoring program.
What process did the SWG use in
developing the plan?
- Ecology allowed the SWG to use a great deal of flexibility to create a
regional approach to stormwater monitoring. Municipal participants knew there
would be monitoring in the next Phase II municipal stormwater permits and wanted
to avoid the potential requirement to replicate current Phase I monitoring. The
SWG spent almost two years developing a scientific framework and an
implementation plan for regional monitoring. The process included talking to
people who have done this and succeeded elsewhere around the country, two public
comment periods, and three large regional workshops.
- Ecology is offering a similar level of flexibility and responsibility to
permittees and stakeholders in southwest and eastern Washington in developing
their monitoring proposals.
What are the advantages to local
governments of adopting this regional approach?
- The regional stormwater monitoring program will help evaluate whether
stormwater management actions, in aggregate, are resulting in statistically
significant improvements surface water quality. In addition, the plan will:
Help permittees meet
Municipal Stormwater Permit stormwater monitoring requirements by lowering
current and potential monitoring costs associated with that permit element.
Reduce duplication of
effort by requiring a pooling of resources with other permittees to perform
required monitoring. Ensure that consistent methods and protocols are used,
and the resulting information is easily accessible by all interested
Allow permittees to pay
into a collective fund to conduct the monitoring and thereby relieving them
of the responsibility to collect monitoring information themselves.
adaptive management by providing information about how our management
actions are doing, in aggregate, and how we can improve our approach.
Why is Ecology recommended as the
initial administrator of the funds?
- The SWG considered numerous
potential entities that might serve this important role and ultimately concluded
that Ecology provides the only viable option at this time because Ecology is the
only entity with the administrative capacity and willingness to assume this role
and responsibilities for the next municipal stormwater permit. A different
organization might be chosen for subsequent permits, or for the southwest or
eastern Washington programs.
When do the permit requirements go
The proposed stormwater monitoring requirements would go into effect after the
next NPDES municipal stormwater permits are issued. Phase I permittees would
contribute funds in the first year new permits are effective. Phase II
permittees in western Washington would contribute funds in the second year the
new permits are effective. During the second year the new permits are effective,
the program would begin to conduct effectiveness studies. The second and third
years of the new permit would also be dedicated to preparing for monitoring
receiving waters in the fourth.
- Permittees in eastern
Washington would contribute funds to begin effectiveness studies in the third
year the new permits are effective. They would contribute funds to prepare for
receiving water monitoring during the fourth year the new permits are effective,
and to fully implement the program during the fifth year the new permits are
What are the next steps?
- Ecology is releasing
preliminary draft permit monitoring language in May 2011 for public review and
comment. The public comment on formal draft permits will begin in October 2011.
The final permits are expected to be issued in July 2012.
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