In accordance with federal Clean Water Act (CWA) requirements, the NPDES section developed a general permit that authorizes the discharge of biological pesticides and chemical pesticides that leave a residue from point sources to waters of the United States. The general permit covers discharges resulting from the application of pesticides to control aquatic nuisance insects and animals, weeds, algae, bacteria, fungi, fish parasites, and forest canopy pests.
While the Pesticides General Permit (PGP, General Permit #7, or GP #7) provides coverage under the CWA, there are also separate state-based requirements for applying pesticides to public waters. These state requirements must also be followed, and the rules can be found in the Iowa Administrative Code at 571 IAC Chapter 54. For more information on other state requirements for pesticides, please see the webpage of the Pesticide Bureau of the Iowa Dept. of Agricultural and Land Stewardship .
Current Pesticides General Permit
The first version of GP #7 became effective on March 30, 2011. GP #7 has been reissued three times. The current version is effective from July 1, 2023 to June 30, 2028. Please note, Notices of Intent (NOIs) are not required for coverage under the reissued general permit. See the following links for more information concerning GP #7 and the waterbodies referenced in the permit.
Final General Permit #7 and Additional Information
Waterbody Reference Tables for Pesticides General Permit
- Iowa Waterbodies Designated for Drinking Water Use (Class C)
- Outstanding Iowa Waters (OIW) Map
- Outstanding Iowa Waters (OIW) Webpage - contains links to individual maps of the OIWs
Renewal of GP #7
The DNR is hosting an informal stakeholder meeting on March 3, 2026, regarding the proposed five-year renewals of NPDES General Permits #5, #6, and #7 (GPs #5-7). The purpose of this meeting is to accept comments and answer questions on possible changes to the GPs. The DNR is specifically seeking comments on the clarity, feasibility, and potential impact of the proposed changes. Formal rulemaking to renew GPs #5-7 is expected to begin in mid 2026.
The meeting will be held on Tuesday, March 3 at 11:00 am. The meeting is open to the public and will be held virtually via Google Meet.
- Tuesday, March 3 · 11:00am
- Video call link: https://meet.google.com/ajr-zgmd-fwa
- Or dial: ‪(US) +1 435-610-2961 PIN: ‪535 972 313#
- More phone numbers: https://tel.meet/ajr-zgmd-fwa?pin=7706104156826
Questions and comments regarding the draft renewals or the meeting may be directed to Wendy Hieb at wendy.hieb@dnr.iowa.gov. Comments will be accepted until Tuesday, March 10th.
Redline-strikeout version of the draft renewal of GP #7 (2026-1-30)
Pesticide Discharge to Class C Waters (Drinking Water)
The Pesticides General Permit requires you to obtain prior authorization from the Iowa DNR for pesticide discharges near shallow wells and to Class C (drinking) waters.
In order to request authorization, you will need to complete and submit a Class C Waters Form at least ninety days prior to the planned pesticide application.
Pesticide Applicator and Licensing Questions
If you have questions on topics other than GP7 or the Class C Waters form, please contact the Pesticide Bureau of the Iowa Dept. of Agricultural and Land Stewardship at 515-281-8591 or pesticides@iowaagriculture.gov.