Construction Stormwater General Permit

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We have transitioned to a Modern Work Environment. To expedite application processing, 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.

Stormwater runoff from construction sites can carry muddy water, debris, and chemicals into local waterways. Sediments, chemicals, and debris can harm aquatic life and reduce water quality.

We require regulated construction sites to get coverage under the Construction Stormwater General Permit (CSWGP). Following the requirements in this permit helps control and reduce water pollution. If water on your construction site is contaminated see this guidance for contaminated water on construction sites.  

Operators of regulated construction sites are required to:

  1. Develop stormwater pollution prevention plans.
  2. Implement sediment, erosion, and pollution prevention control measures.
  3. Obtain coverage under this permit.

The current permit went into effect on Jan. 1, 2021, and expires on Dec. 31, 2025.

To receive updates about this permit, sign up for our email list.

Applications and forms

I've got permit coverage. Now what?

Check out our eCoverage packet for more information about your requirements.

Need help implementing the permit?

What do I do with contaminated water?

See contaminated water on construction sites for guidance.

Not finding what you're looking for?

See our regional contacts page to help find a person to answer to your questions.