Aquatic Plant and Algae Management - NPDES General Permit

What is the purpose of this permit?
This permit allows businesses and local governments to apply chemical treatments for the management of aquatic noxious weeds, native nuisance plants, and algae and ensures water quality is protected.
Who issues this permit?
Department of Ecology
What activities require this permit?
Activities that result in a discharge of aquatic-labeled herbicides, algaecides, biological water clarifiers, adjuvants, marker dyes, shading products, and phosphorus inactivation products into freshwater (lakes, streams, and rivers) or along shorelines, roadsides, dikes/levees, and ditch banks. To find out the specific activities that trigger this permit, see Special Condition S1 on page 2 of the current permit or page 17 of the fact sheet. You can download both documents from the Aquatic Plant and Algae Management Permit website under Current Permit Documents.
How much will this permit cost?
There is no fee to apply for permit coverage. After Ecology approves your application, we will send you a bill for the annual permit fee, which is currently $500. Permit fees change over time, so please check the Permit Fee schedule in WAC 173-224-040.
Where can I get the application for this permit?
The application is called 'Notice of Intent (NOI) Application Form for Coverage Under the Aquatic Plant and Algae Management General Permit' is online and can be accessed at
Do I need to include anything with my application?
At a minimum, you must include a map of the proposed treatment area. See the application instructions for other required documents.
  • A map of the proposed treatment area.
  • A signed and dated Fluridone Vegetation Management Plan (See Appendix C of the general permit) when applying for permit coverage that includes fluridone treatment of more than:
    • Fifty percent of the littoral zone in lakes up to 50 acres.
    • Forty percent of the littoral zone in lakes from 50 - 500 acres.
  • Copy of the written consent from the municipality or community when applying for permit coverage that includes using a product that is restricted for use in potable water and the treatment occurs in water bodies with municipal or community drinking water intakes.
Is the decision on my permit dependent on anything besides the information in my application?
When making the decision on your application, Ecology will consider the laws and rules that apply and the contents of your application.

In addition, the permitting process includes public participation. This means the public may submit comments to Ecology during the 30-day public comment period to support or oppose your proposed activity. If any comments are received, Ecology must review and respond to the comments and consider them when making the decision to issue or deny permit coverage.
How long will it take to review my application?
Generally, 45 to 60 days, which includes the 30-day public comment period. See the Permit Timeliness Results below for average processing times.
    WAC 173-226-200 and RCW 90.48.170: Application for permits shall be made at least 60 days prior to commencement of any proposed discharge or permit expiration date, whichever is applicable. Ecology can issue coverage on the 38th day following receipt of a complete application and the publication of the first public notice in a newspaper of general circulation in the county.
    Where do I submit my application?
    You must apply for the permit online, through Secure Access Washington (SAW), and send a signed hardcopy of your application to Ecology. See the Notes/Comments section below for more information on applying through SAW.
    How long is my permit valid?
    Ecology issues general permits for a five-year period. Your coverage under the general permit is valid from the day Ecology issues your permit coverage, to the day the general permit expires at the end of the five years.

    You can terminate your permit coverage before the permit expires by sending Ecology a Notice of Termination. You should not terminate your permit coverage unless the pesticide discharge you are permitted for will no longer occur.

    If you fail to pay your yearly permit fee, Ecology will cancel your permit coverage.
    What is the appeal process for the permit?
    An order, permit, license, or decision can be appealed within 30 days from the “date of receipt” of the decision. The appeal process is governed by RCW 43.21B and WAC 371-08. “Date of receipt” is defined in RCW 43.21B.001(2). Get more information on the Pollution Control Hearings Board’s webpage.
    Notes / Comments:
    You must apply for the permit online, through Secure Access Washington (SAW), and submit a signed hard copy of your application to Ecology.
      Apply online
        The permit application is available online through Secure Access Washington (SAW). Applicants must register for a user account through SAW, and then apply for access to the Secure Service for the pesticide permit they are applying for. This initial setup takes longer than filling out a paper application but reduces time and paperwork in the long run by allowing applicants to submit applications, annual reports, and updates online. Get the instructions for how to apply for aquatic pesticide permit coverage on the Aquatic Plant & Algae Management General Permit web page Aquatic Plant & Algae Management General Permit.
          Start the process
            Get your SAW user account at
              Send hard copy to Ecology
                Send the signed hard copy of each application, along with a treatment area map, to Ecology to satisfy the Environmental Protection Agency reporting requirements.
                  Department of Ecology
                  Water Quality Program
                  Attn: Aquatic Pesticide Permit Manager
                  PO Box 47600
                  Olympia, WA 98504
                For additional help, please contact the Ecology staff listed at the bottom of the Aquatic Plant and Algae Management General Permit webpage.
                Legal Authority:
                Permit Timeliness Results

                Permit Timeliness data collection is in response to a State Auditor’s Performance Audit and RCW 43.42A. Each regulatory agency developed a plan to improve permit clarity, predictability, and timeliness. Each agency considers the customers experience to ensure permit assistance is simple to use, easy to access, and designed in a customer-friendly manner. Agencies report progress to the Governor’s Office for Regulatory Innovation and Assistance (ORIA). ORIA prepares and distributes reports, with participation from the State Auditor’s Office and Results Washington. See latest report here:

                All permits submitted for reporting were entered into this Regulatory Handbook. Here are the results of the performance data:

                Estimated Time Required By the Agency to Process a Permit Application (Definition)
                Average number of days from Receipt to Complete: 14
                Maximum number of days from Receipt to Complete: 56

                Estimated Time Required By the Agency to Issue a Permit Decision (Definition)
                Average number of days from Complete Application to Decision: 36.3
                Maximum number of days from Complete Application to Decision: 65

                (Summary results based on 4 submittals in 2020, no data for current year)

                Where can I get permitting assistance?
                Web page URL:
                Department of Ecology
                300 Desmond Drive
                PO Box 47600
                Olympia, WA 98504-7600
                Telephone: (360) 407-6000
                Triggering Questions:
                • Do you plan to: apply aquatic herbicides or nutrient inactivators into lakes, rivers or other water bodies to control aquatic plants or apply aquatic herbicides to control native vegetation in riparian areas?
                * Permit information last updated 1/24/2024