Irrigation System Aquatic Weed Control permit

The Irrigation System Aquatic Weed Control (ISAWC) permit allows the regulated use of aquatic pesticides, marker dyes, and nutrient-inactivation products to control the growth of aquatic plants and algae within irrigation systems, helping them to maintain the capacity to convey water.

The current permit went into effect on Oct. 2, 2023, and expires on Oct. 1, 2028.

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Join our ISAWC email notification list to receive ISAWC updates.

Interested in our other aquatic-pesticide permits? Join our Aquatic Pesticide Permits email notification list for updates.

Permit reissuance

We have reissued the Irrigation System Aquatic Weed Control General Permit. Previously, we held a comment period on the draft permit documents from Jan. 18 until March 20, 2023. The Environmental Impact Statement for this permit was published on Aug. 16, 2023. 

 Irrigation canal passing through fields in Roza Irrigation District

Current permit documents

Current Environmental Impact Statement (EIS) documents

Historic permit documents

Comment period

The comment period was open Jan. 18 – March 20, 2023. We collected comments online, by mail, and during our public hearings.

Comments are available for viewing through our online comment form.

Workshop and hearings

During the workshops in late February, we explained the proposed changes to the permit and environmental impact statement and answered questions. The hearing began immediately following the public workshop. 

View the Irrigation System and Aquatic Weed Control workshop and hearing presentation

Apply for permit coverage

To submit an electronic permit application, also known as a "Notice of Intent" (NOI), through the WQWebPortal:

  1. Sign up for a SecureAccess Washington (SAW) account. SecureAccess Washington or SAW is the State of Washington’s secure portal to access and submit applications.
  2. Add the WQWebPortal Service to your SAW account to apply for coverage. 
  3. Follow these instructions to submit an electronic NOI if you do not have permit coverage.