Industrial Stormwater General Permit

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Coronavirus (COVID-19) status update

To expedite application processing please scan or take a photo of all forms and email them to us at When you are able, please still mail us signed original documents.

We continue to process electronic permit related documents, but we may have extended turnaround times. We are currently emailing coverage letters and other documents to the permittee on file.

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

Stormwater can pick up pollution from factories and businesses. Those contaminants are carried into waterways and harm fish and other aquatic life. The Industrial Stormwater General Permit (ISGP) helps industrial facilities comply with federal regulations that reduce pollution. We require most industrial sites in Washington to monitor, measure, and reduce stormwater pollution leaving their site.

The current permit went into effect on Jan. 1, 2020 and expires Dec. 31, 2024.

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Current permit and related documents

  Current applications and forms, and historic permit documents