Industrial Stormwater General Permit

Stormwater can pick up pollution from factories and businesses. Those contaminants are carried into waterways and can harm fish and other aquatic life. The National Pollutant Discharge Elimination System (NPDES) and State Waste Discharge permit helps industrial facilities comply with federal and state regulations that reduce pollution. We require most industrial sites in Washington to monitor, measure, and reduce stormwater pollution leaving their site. We use the federal Clean Water Act and state law (RCW 90.48.080) to regulate stormwater at industrial facilities.

The current permit went into effect Jan. 1, 2025, and expires Dec. 31, 2029. Under the modification, the permit will expire Dec. 31, 2028, rather than Dec. 31, 2029.

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Current permit documents

2025 Industrial Stormwater General Permit with errata (effective Jan. 1, 2025)
- Permit errata
- Appendix 3: SWPPP certification form
Fact sheet for the draft 2025 general permit
- Appendix C: Response to Comments
Focus on: 2025 Industrial Stormwater General Permit (Dec. 2024)
Small Business Economic Impact Analysis (May 2024)
Redline version of the 2025 permit

Modification

The public comment period is now closed for the draft permit modification. We are reviewing and considering all comments received. We will develop a final draft of the permit based on comments, and publish an official response to comments as an appendix to the fact sheet. A final decision on permit issuance is expected later this October.

Documents for the draft modification

Draft modified general permit
Redline version of the draft permit
Addendum to the fact sheet for the draft major modification to the Industrial Stormwater General Permit — explains the changes in the draft modification
Presentation from the public meeting and hearing on the draft modification (September 2026)
Washington State Register public notice of draft release (WSR 26-16-07, Aug. 19, 2026)

Public involvement

Ecology provided public notice of the draft modified general permit release in the Washington State Register (WSR 26-16-07, Aug. 19, 2026) and accepted public comments from Aug. 19, 2026, through Oct. 2, 2026. We hosted one public meeting and hearing on Sept. 23, 2026, to help explain the draft permit's proposed changes and provide opportunity for formal spoken testimony on the draft permit.

Anticipated timeline

Oct. 2, 2026: Public comment period closes
October 2026: Make final permit reissuance decision
November 2026: Issue final major modification
As early as Winter 2026: start the process for full reissuance
Early 2028: Public comment on the 2029 draft permit

railroad tracks with stacks of both covered and uncovered wooden boards — Transportation facility

The 2025 ISGP was appealed to the Pollution Control Hearings Board (PCHB): PCHB No. 24-088c Puget Soundkeeper Alliance et. al. v. Ecology

On 6/12/2026 the PCHB issued Findings of Fact and Conclusions of Law, and Order (PCHB Order) affirming the ISGP as valid.

On 7/13/2026 Puget Soundkeeper Alliance and Spokane Riverkeeper filed an appeal of the PCHB Order with King County Superior Court.

The 2025 ISGP remains in full effect.

Applications and forms

To apply for coverage:

Fill out the online application (Notice of Intent)
Conditional No Exposure — Eligible if there is “no exposure” of industrial materials and activities to rain, snow, snow melt, and/or runoff. Reapply for this status every five years. Apply through SecureAccess Washington (SAW).

Please scan or take a photo of all permit forms and email them to our resource mailbox at: ecyrewqianoi@ecy.wa.gov. Also, you must mail the original, signed documents to:

Water Quality Program
PO Box 47696
Olympia, WA 98504-7696

We are currently emailing all coverage documents and permit related information to the permittee on file.

If you have any questions, contact us at the email addresses below.

Historic documents

Contact information

Permit Administrator - by county of permit project

King (except city of Seattle)
Alyssa Brewer
564-669-4922
alyssa.brewer@ecy.wa.gov

City of Seattle, Chelan, Clallam, Douglas, Island, Jefferson, Kittitas, Pacific, San Juan, Skamania, Spokane, Whitman
Max Graham
564-200-2505
max.graham@ecy.wa.gov

Adams, Asotin, Benton, Columbia, Franklin, Garfield, Grant, Grays Harbor, Kitsap, Skagit, Thurston, Walla Walla
Jasper Sogn
360-972-6524
jasper.sogn@ecy.wa.gov

Cowlitz
Joyce Smith
360-628-2138
joyce.smith@ecy.wa.gov

Ferry, Lincoln, Mason, Okanogan, Pend Oreille, Snohomish, Stevens, Wahkiakum, Yakima
Collin Smith
564-669-9319
collin.smith @ecy.wa.gov

Clark, Lewis, Klickitat
Jen Smith
360-584-8214
Jen.smith@ecy.wa.gov

Pierce, Whatcom
Melinda Wilson
360-870-8290
melinda.wilson@ecy.wa.gov