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Stormwater Regulatory Developments: Construction and Logging Operations

Posted on by Farallon

Recent stormwater-related developments have heightened regulatory requirements for construction and logging operations.  Highlights of these developments and sources for additional information are provided below.  The engineering and stormwater management professionals at Farallon Consulting can assist you with these requirements to ensure compliance.


Construction projects that disturb the ground surface may be subject to stormwater permitting requirements calling for coverage under the Washington State Construction Stormwater General Permit (CSGP).  Over 2,400 Washington sites currently are covered under the CSGP.

Water quality goals for navigable (surface) waters of the United States were established by the Federal Water Pollution Control Act (Clean Water Act).   One of the mechanisms for achieving Clean Water Act goals is the National Pollutant Discharge Elimination System (NPDES) permit program, administered by the U.S. Environmental Protection Agency (EPA).  The NPDES permit program regulates point sources that discharge pollutants into United States waters.  The Clean Water Act prohibits discharge of a pollutant from a point source into United States waters without an NPDES permit.  EPA has delegated administration of the NPDES permit program in Washington State to the Washington State Department of Ecology (Ecology).

In 2005, Ecology issued the CSGP for stormwater discharges associated with construction activity.  The CSGP complies with the Clean Water Act and the State of Washington Water Pollution Control Law, and remained in effect until December 2010, when it was renewed with some modifications.  The revised CSGP generally includes only minor changes, with refined and clarified wording and more specific language in response to Pollution Control Hearings Board orders resolving appeals to the existing CSGP.  If current CSGP permittees responded to the March 2010 letter from Ecology by submitting a request for permit renewal, their permit coverage will continue from January 1, 2011 through 2015.

Required Monitoring and Reporting

The CSGP requires permitted operations to implement all known, available, and reasonable methods of prevention, control, and treatment in the form of appropriate best management practices (BMPs) for construction activity prior to discharge of stormwater to Washington State waters.  Once site earthwork has begun, site inspections by a Certified Erosion and Sediment Control Lead generally should be conducted weekly.  Results of site inspections are recorded in the Site Log Book maintained at the site during construction activities.  Monitoring is required at all points where water from a site discharges to waters of Washington State.  Samples of water discharged from a site to State surface waters generally should be collected weekly for turbidity/transparency measurements and possibly pH.  The CSGP specifies target benchmark values for turbidity/transparency and pH, and describes Ecology reporting measures, and corrective actions for instances when benchmark values are exceeded or high turbidity conditions exist.  The CSGP specifies additional monitoring requirements for discharges to water bodies listed by the State as impaired under Section 303(d) of the Clean Water Act or to water bodies subject to applicable Total Maximum Daily Load requirements.Ecology also requires monthly Discharge Monitoring Reports (DMRs) documenting monitoring results.  The 2010 addition of the Web-based tool “WebDMR” streamlines monthly reporting by enabling electronic submittal of DMRs via the Internet. More information on WebDMR is available here.

Stormwater Pollution Prevention Plan

Operators of regulated construction sites also are required to develop a Stormwater Pollution Prevention Plan (SWPPP) that includes narrative and drawings, prepared and implemented in accordance with the CSGP.  The SWPPP must address all phases of the construction project, from initial soil disturbance through final site stabilization.  Erosion and sediment control BMPs implemented or planned for a project must be clearly referenced in the SWPPP narrative and marked on accompanying drawings.The SWPPP is considered a living document that reflects changes that occur during the phases of construction, and must be revised as necessary to include additional or modified BMPs selected from an Ecology-approved stormwater management manual applicable to the site.  These adaptive management requirements are designed to result in permit compliance and prevent stormwater discharges in violation of State water quality standards.  If an inspection indicates a compliance concern, revisions to the SWPPP must be completed within 7 days and include an updated timeline for BMP implementation.  Required BMP revisions must be implemented on the site in a timely manner. A SWPPP prepared in accordance with CSGP guidelines is critical to successful control of pollution from construction site stormwater, and must include documentation to explain and justify pollution-prevention management of the project.  Farallon offers the technical expertise necessary to prepare a site-specific SWPPP in compliance with the CSGP, and has assisted a variety of businesses with SWPPP development and implementation.

Applying for CSGP Coverage

Construction operators apply for project coverage under the CSGP by filing a Notice of Intent Application Form with Ecology at least 60 days prior to commencement of construction activities.  Permitting involves a review process by Ecology and the public.  Upon completion of the review process, the project either is approved for permit coverage or denied.  An appeals process to contest Ecology’s decision is available to both applicants and the public.

New facilities seeking a CSGP must demonstrate compliance with the State Environmental Policy Act (SEPA) before CSGP coverage can be authorized.  Revising permit coverage for physical alterations, modifications, or additions to the construction site also requires SEPA compliance.  Additional SEPA review may be necessary if a modification is outside the scope of the initial SEPA evaluation.

Available for review on the Ecology Web site are a CSGP fact sheet and the revised CSGP.


Effluent Limitations Guidelines

Another significant change relates to the Effluent Limitations Guidelines published by EPA effective February 1, 2010.  These Guidelines limit maximum daily average turbidity in stormwater discharge from construction sites larger than 10 acres of disturbed land to 280 nephelometric turbidity units (NTU).  In August 2010, EPA conceded that the numeric turbidity limit is flawed and requires reevaluation.  The 7th Circuit Court of Appeals granted EPA’s request to remand the Rule and hold the suit in abeyance until February 2012, but refused to vacate the numeric limit.  The numeric turbidity limit is still enforceable under EPA’s construction stormwater rule.   Ecology proposed not using the compliance deadlines published by EPA (August 1, 2011 for ≥20-acre sites; February 2, 2014 for ≥10-acre sites).  Instead, effective January 1, 2011, Ecology requires all sites disturbing 10 or more acres of land at one time to comply with the 280 NTU effluent limitation.

Logging Operations

In August 2010, the Ninth Circuit Court of Appeals ruled that logging operations are “industrial,” and that stormwater management devices such as culverts and other systems that modify natural stormwater flows and direct them to a receiving water body of Washington State are “point sources” rather than “non-point sources,” as inferred from historical interpretation of EPA’s 30-year-old Silvicultural Rule.  Because road construction and maintenance activities involving natural runoff were interpreted under the Silvicultural Rule to be non-point source silvicultural activities, they were interpreted to be outside the NPDES program.  The August 2010 decision changed this interpretation, specifically concluding that runoff from logging road construction and operation requires permitting under the Clean Water Act and the NPDES program.  EPA was charged with developing a general permit to handle the discharges.  Although the August 2010 court decision likely will be appealed, owners and operators face the threat of citizen suits and enforcement actions for unpermitted discharges. 


Related stormwater specifics, forms, and fact sheets are available from the Ecology Web site here.

Additional information is provided on the Washington State Governor’s Office of Regulatory Assistance Web site—Environmental Permit Handbook: NPDES Construction Stormwater General Permit.


Preparing and maintaining SWPPPs and implementing appropriate BMPs should be an immediate priority for construction operators to ensure compliance with the CSGP.  Farallon recommends that permittees seek professional technical and legal assistance to minimize the risk to business operations that may result from noncompliance under revised CSGP in effect. For additional information or questions regarding stormwater management,contact Stacy Patterson at (425) 295-0812.

Who Needs Coverage Under the CSGP? 

When construction work involves clearing, grading, and/or excavation resulting in disturbance of 1 acre or more and discharge of stormwater to Washington State surface waters, construction operators must apply to Ecology for coverage under the CSGP.

Coverage under the CSGP is required also when clearing, grading, and/or excavation on sites smaller than 1 acre is part of a larger common plan of development or a sale that disturbs 1 acre or more and discharges stormwater to surface waters of Washington State.

Ecology can require CSGP coverage for any size construction activity discharging stormwater to Washington State waters at its discretion. Some construction sites or activities are exempted from coverage under the CSGP. Operators may apply for a waiver for sites smaller than 5 acres having low rainfall erosivity conditions.

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