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Water Quality Program

Construction Stormwater General Permit

Construction site operators are required to be covered by a Construction Stormwater General Permit if they are engaged in clearing, grading, and excavating activities that disturb one or more acres and discharge stormwater to surface waters of the state. Smaller sites may also require coverage if they are part of a larger common plan of development that will ultimately disturb one acre or more. 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.

Permit Appeal and Proposed Modification

The current permit was appealed and a settlement agreement was reached for a minor permit modification. The Final CSWGP Modification with a Response to Comments was issued on March 22, 2017. Proposed changes went into effect May 5, 2017. Read and print the final permit changes and response to comments.

I have permit coverage. Now what? Find out more by reading our eCoverage Packet

Permit, Forms and Documents

Discharge Monitoring Reports (DMRs)

Permit and Reporting Information System (PARIS)

Contact Us - Contact your Permit Administrator for permit assistance or your Regional Office for site specific questions.

High Turbidity Reporting - Construction projects must report high stormwater turbidity results within 24 hours by phone or electronically. If you get a high result, call your Ecology regional office.

Resources and Guidance - DMRs, Stormwater monitoring, manuals, 303(d) list information, CESCL.

Historical Information

Sign up for the Construction Stormwater General Permit email listserv

Questions? Contact Amy Moon at 360-407-6467 or amy.moon@ecy.wa.gov


Online Application (eNOI) Now Available

Erosivity Waiver Calculator | Fact Sheet

Site Inspection Form

Request for Chemical Treatment Form

Sampling Frequently Asked Questions

Permit Application Status

Stormwater Pollution Prevention Plan Template

Everett and Tacoma Smelter Search

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