WSR 23-22-116
[Filed October 31, 2023, 2:48 p.m.]
Announcing the Draft Aquatic Mosquito Control General Permit and Fact Sheet for Review and Comment
The Washington state department of ecology (ecology) proposes to reissue the Aquatic Mosquito Control National Pollutant Discharge Elimination System and state waste discharge general permit (permit). The current permit was last issued in June 2019 and is scheduled to expire July 4, 2024. The revised draft permit and fact sheet, which explains the legal and technical basis for the permit, are available with any associated documents for review and public comment from November 15, 2023, through December 29, 2023, 11:59 p.m. Ecology will host informational workshops and public hearings on the draft permit.
Purpose of the Permit: The permit provides statewide coverage for the use of specific insecticides to control mosquitoes. Under federal and state water quality laws (Federal Clean Water Act and State Water Pollution Control Act), a permit is required for the discharge of larvicides or adulticides to control mosquitoes. Individuals, businesses, and government entities that apply pesticides either directly or indirectly to waters of the state must obtain permit authorization for their discharge. This permit doesnot apply to homeowner use of insecticides for residential control of mosquitoes.
Applying for Coverage Under the Permit: Permittees that have applied for renewed coverage by January 5, 2024, will continue to be covered under the existing permit until the new permit is issued. Obtain new coverage under the permit by submitting a complete permit application to ecology and satisfying all applicable public notice and State Environmental Policy Act (SEPA) requirements (WAC 173-226-200). Access to the application is available online at
Copies of the Draft Permit and Fact Sheet: The draft permit and fact sheet are available online at You may request hard copies from Jackie Lince at or 360-407-6600.
Submitting Written Comments: Ecology will accept written comments on the draft permit from November 15, 2023, through December 29, 2023, 11:59 p.m. Ecology prefers online comment submission via the eComment form (link below) on the permit web page. Written comments by mail must be postmarked by December 29, 2023. Comments should reference specific permit text when possible.
Online via the eComment form (preferred):
By mail: Send to Shawn Ultican, Washington State Department of Ecology, P.O. Box 47696, Olympia, WA 98504-7696, phone 360-407-6283, email
Assistance for Persons with Disabilities: To request ADA accommodation for disabilities, call ecology at 360-407-7285 or visit People with impaired hearing may call Washington relay service at 711. People with speech disability may call TTY at 877-833-6341.
En Español: Para información en español, por favor comuníquese con Shawn Ultican al 360-407-6283.
Public Workshop(s) and Hearing(s): The purpose of the workshops is to explain the general permit and to answer questions prior to the formal public hearings. The purpose of the hearings is to provide an opportunity for people to give formal oral testimony and written comments on the proposed draft permit. Oral testimony will receive the same consideration as written comments.
The public hearings will begin immediately after the public workshops and will conclude when public testimony is complete.
The aquatic mosquito control online workshops and hearings will occur on December 19, 2023, at 9:00 a.m. Register for the webinar; and on December 20, 2023, at 5:30 p.m. Register for the webinar
Issuing the Permit: After ecology receives and considers all public comments, we will make a final decision about issuing the aquatic mosquito control permit. Ecology expects to make this decision in May 2024.