Hide Alert

Welcome to our new website. Learn more about what's new.

Construction Stormwater General Permit

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 modified permit went into effect May 5, 2017 and expires Dec. 31, 2020.

To receive updates about this permit, sign up for our listserv

Do I need permit coverage?

Current permit and recent modification

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.

Contacts for assistance

Central Region

For permittees located in the following counties:

Benton, Chelan, Douglas, Kittitas, Klickitat, Okanogan, and Yakima

Joyce Smith
Permit Administrator

Eastern Region Southwest Region Northwest Region