FIFRA for decades regulated at the federal level all aspects of pesticide use, and it was, until 2009, uncommon for Clean Water Act (CWA) rules to come into play for the aerial application industry—for example, avoiding applications outside of buffer zones set up around specific aquatic habitat and wetlands, or to impaired river segments or lakes covered by Total Maximum Daily Loads (TMDLs) designed to help meet state water quality standards. However, a 2009 decision of the Sixth Circuit U.S. Court of Appeals (National Cotton Council, et al., v. EPA) brought the full weight of the CWA into the realm of FIFRA and aerial application businesses. With this ruling, pesticide applications made into, over or near “waters of the U.S.” according to FIFRA product labels must also comply with the additional requirements of an NPDES pesticide general permit (PGP).
As much as aerial and ground contract pesticide applicators were affected by this ruling, government agencies with pest control responsibilities are even more affected. These include primarily federal, state, and municipal water programs and pest control agencies, for they are the “decision makers” who must comply with the broadest range of PGP requirements. Also, in this group can be public health agencies and mosquito control organizations; wildlife agencies and large aquatic weed control companies; irrigation districts; managers of highways, roads and utility rights-of-ways; and forest and park managers. Obviously, there is a lot of shared burden, especially for a permit that most states agree contributes little environmental benefits over existing FIFRA and state pesticide programs.
The types of pesticide applications that are regulated by the permit include: mosquito and other flying insect pest control; weed, algae and pathogen pests in waters at water’s edge, including ditches and/or canals; animal pest control in water and at water’s edge; and forest canopy pest control where a jurisdictional waterbody is under the canopy and may be affected by the applied pesticides. Some state PGPs add other covered uses, such as for control of weeds on right-of-way or in rangeland. An explanation of the types of parties that are likely to fall into these use categories is available on EPA’s pesticide permitting webpage.
To meet the court’s requirement, EPA and 45 separate states first developed PGPs in 2011 and have been implementing them since. These five-year permits vary widely in requirements. Permit fees vary from a few hundred dollars to over $1,000 in some states, and PGPs have increased compliance costs and manpower resource needs for all involved. Worse than these costs, however, is the legal risk – failure to comply with the permits can result in hefty agency fines and penalties, as well as potential citizen suits over alleged violations. For the states in which NAAA members operate, it is imperative aerial applicators know what is needed to avoid violating these PGPs and triggering enforcement action, or worse, citizen suits.
State PGPs differ significantly: EPA’s PGPs regulate pesticide applications in Massachusetts, New Hampshire, New Mexico, and Idaho and the District of Columbia; all U.S. territories except the U.S. Virgin Islands; federal facilities in Delaware, Vermont, Colorado, and Washington; discharges in Texas that are not under the authority of the Texas Commission on Environmental Quality, including activities associated with oil and gas exploration; and all areas of Indian Country that are not covered by an EPA-approved permitting program. The other 44 states not covered by EPA’s PGP have some form of state PGP in place, but they do vary considerably. That means if you have pesticide applications that extend across state borders you may need to comply with a number of different PGP requirements.
State PGPs fall into three categories: 1) PGPs which have extensive compliance requirements for all dischargers (e.g., NY, CA, KY, WA, WI); 2) PGPs which extend automatic coverage and legal protections to all operators as long as they meet permit conditions (e.g., LA, SD, MD, VA, ND, CO); and 3) PGPs that only have extensive requirements for government agencies and other large entities whose pesticide applications exceed annual treatment thresholds, but modest requirement for others below annual thresholds (e.g., FL, IA, OH, SC, PA, OR). To compare state permits, NAAA has analyzed each state’s permit and contrasted them in a state permitting chart.
It is important aerial applicators know which PGP requirements apply to their businesses. To help educate members, NAAA has developed a comprehensive document that outlines aerial applicator’s obligations under the NPDES pesticide general permit. In the PGP, applicators have less burdensome requirements than government agencies, landowners, and other major pest-control decision-makers who have control over pesticide applications into, over or near US waters. However, if an aerial applicator makes the pesticide application decisions for his clients, that applicator may become a “decision-maker” and then must comply with all applicable requirements imposed on both applicators and decision-makers. It is important that aerial applicators know what distinguishes the requirements of “for-hire” applicators from those of “decision-makers.” Thus, operators and their clients should have an agreement in place clearly delineating the role of the client decision-maker and applicator for each application made. To assist NAAA members, NAAA has developed sample contract language for reference when preparing contract negotiation with clients delineating that the aerial applicator is not the decision-maker.
In November 2023, EPA released the draft 2026 PGP. On October 4, 2021, the Center for Biological Diversity (CBD) filed a petition for review with the Ninth Circuit regarding the 2021 Pesticide General Permit (PGP). EPA, U.S. Fish and Wildlife Services, and CBD entered into a settlement agreement on July 25, 2023 to resolve the litigation. On December 19, 2024, CBD filed a consent motion to voluntarily dismiss the appeal. As part of the Settlement Agreement, EPA agreed to issue the final 2026 PGP on or prior to December 17, 2024. The permit would still take effect October 31, 2026, when the current 2021 PGP expires.
NAAA’s commented on the 2026 draft and its comments were like its earlier comments and touched on the redundancy of the PGP, considering that all pesticides, including those for aquatic sites, already undergo a registration and then a reregistration review process to verify their safety to the environment when used according to label directions. NAAA did point out that Endangered Species Act (ESA) requirements on the PGP are yet another redundancy considering EPA’s recent spate of efforts to address ESA issues in pesticide registration and review processes. NAAA also expressed concerns about updated site monitoring and record keeping requirements, some of which fall on the applicator. NAAA pointed out these requirements have the potential to be overly burdensome to aerial application operations, many of which are small businesses. Other industry comments also urge the EPA to eliminate joint and several liability provisions from the PGP, as they set a concerning precedent for their activities. Also, requests were made for clarification that the PGP does not apply to stormwater discharges that do not currently require an NPDES permit
Notable changes in the draft 2026 National Pollutant Discharge Elimination System (NPDES) Pesticide General Permit (PGP) compared to the 2021 PGP. Key proposed modifications include Enhanced Visual Monitoring and Documentation:
- Introduction of Part 4.3, “Documentation of Visual Monitoring,” emphasizing the requirement to record visual monitoring activities as outlined in Parts 7.2, 7.3, and 7.4.
- Addition of Part 4.4, “Additional Monitoring,” highlighting that EPA may mandate further monitoring to ensure compliance with the PGP.
- Requirement for Decision-makers to submit a Pesticide Discharge Management Plan (PDMP) alongside their Notice of Intent (NOI) as specified in Part 5.
- Inclusion of visual monitoring procedures within the PDMP content requirements.
- Mandate that records of visual monitoring include specific details such as date, time, and location.
- Obligation for Decision-makers to submit visual monitoring records with their Annual Report.
Requirements
All PGPs include these minimum requirements:
- Carefully handle and store pesticide products to avoid leaks and spills
- Promptly deal with spills following manufacturer recommendations
- Comply with the FIFRA labels on products they are hired to apply
- Properly mix and load pesticides into their aircraft
- Properly rinse and recycle/dispose of empty pesticide containers
- Properly clean their spraying system after application
- Preventatively maintain those pesticide-application systems to avoid leaks
- Calibrate aircraft spraying systems so they apply the proper amount of pesticides
- Properly identify and direct the application to desired boundaries using GPS when feasible or on-ground flagging
- Properly apply the pesticide products to the appropriate location and at the proper rate
- Keep proper records of all regulated activities
- Communicate this information to clients in a timely manner for the permit compliance needs of those organizations
- Monitor equipment during application to ensure proper functioning and to avoid off-target application. Records of these activities are necessary, as are spray logs.
NAAA has prepared an NPDES checklist of compliance activities for aerial applicators’ aid in complying with this burdensome task. Should an applicator determine that the manner in which any of these activities is performed is not satisfactory, or should an adverse incident occur for an applicator, the practices would need to be upgraded before the next pesticide application, and any adverse impact reported to the EPA or the state permitting agency.
Legislative Efforts to Repeal NPDES Permit Requirements
Efforts to encourage Congress to address legislative fixes to NCC vs. EPA by NAAA and its ag/pesticide user stakeholder coalition have been underway since the court’s decision in 2009. The House has passed legislation, titled the Reducing Regulatory Burdens Act, that would create a legislative exemption for NPDES permitting of pesticides several times as either free standing legislation or part of various iterations of House Farm Bills. NAAA is working to get NPDES permit relief included in the 2025 Farm Bill.
Waters of The United States (WOTUS)
The CWA does not define WOTUS; since the 1970’s, the EPA and Army have defined it by regulation. Four Supreme Court decisions addressed the definition over the years. The 2015 Clean Water Rule wholly redefined WOTUS but was repealed by a 2019 Rule which reinstated the prior regulations, implemented consistent with the Supreme Court decisions and applicable guidance. However, the 2019 Rule was replaced with the Navigable Waters Protection Rule (NWPR) in 2020, which itself had implementation halted in 2021 due to other litigation.
The “Revised Definition of ‘Waters of the United States’” rule took effect on March 20, 2023 being codified in place of the NWPR. However, effective September 8, 2023, the EPA amended this rule to conform to a Supreme Court decision[1] invalidating the “significant nexus standard” test to identify waters that, either alone or in combination with similarly situated waters in the region significantly affect traditional navigable/interstate waters.
EPA released a proposal to update the definition of Waters of the United States (WOTUS) in November of 2025 that attempts to reduce regulatory burdens and associated costs with compliance. To achieve these aims, EPA proposes narrowing the scope of jurisdiction to relatively permanent waters and wetlands that maintain a continuous surface connection to such waters. The rule also refines key terms, including “relatively permanent” and “tributary,” and clarifies long-debated exclusions for features such as certain ditches, prior converted cropland, waste treatment systems, and groundwater. EPA maintains that these updates directly address longstanding stakeholder requests for clearer, more predictable standards that lessen compliance uncertainty and litigation risk. The agency defines “relatively permanent” to mean “standing or continuously flowing bodies of surface water that are standing or continuously flowing year-round or at least during the wet season.” The agency defines “tributary” to mean “a body of water with relatively permanent flow, and a bed and bank, that connects to a downstream traditional navigable water or the territorial seas, either directly or through one or more waters or features that convey relatively permanent flow.” Further, the proposed definition of “tributary” clarifies that a “tributary does not include a body of water that contributes surface water flow to a downstream jurisdictional water through a feature such as a channelized non-jurisdictional surface water feature, subterranean river, culvert, dam, tunnel, or similar artificial feature, or through a debris pile, boulder field, wetland, or similar natural feature, if such feature does not convey relatively permanent flow.
EPA also underscored the rule’s economic implications, noting that improved regulatory clarity stands to benefit farmers, ranchers, and developers who rely on consistent water-related permitting frameworks. The proposal, if made permanent and remains unchanged by subsequent administrations, will reduce the areas required to obtain a pesticide general permit under the Clean Water Act’s National Pollutant Discharge Elimination System (NPDES). NAAA will continue to advocate for changes to the rule that provide additional clarity for our members about which waters are subject to federal regulation, including NPDES permits.
On December 11, 2025, the House of Representatives passed H.R. 3898, the “Promoting Efficient Review for Modern Infrastructure Today (PERMIT) Act” (HR 3898), which among other permit reforms, would clarify that NPDES permits are not needed for applications for EPA registered pesticides. The legislation was championed by Rep. David Rouzer (R-NC), House Transportation and Infrastructure Committee Water Resources and Environment Subcommittee Chairman Mike Collins (R-GA) and other committee leaders. NAAA encourages the Senate to take similar action. NAAA also supports and advocates for the inclusion of NPDES permit relief in the next Farm Bill or any other appropriate legislation.
[1] Sackett, et ux. v. EPA, et al. (S. Ct. 2023)
Recent Updates
On April 30, the House of Representatives passed the Farm, Food, and National Security Act of 2026 (Farm Bill). The original committee bill included Representative David Rouzer’s (R-NC) “Reducing Regulatory Burdens Act,” which would have eliminated duplicative permitting requirements for pesticide applications over or near water. Adopting Rouzer’s language, Section 10207 would have removed the requirement for an NPDES Pesticide General Permit under the Clean Water Act for applications already approved for water safety under FIFRA. Unfortunately a last minute amendment by led by Representative Anna Paulina Luna (R-FL) which passed decisively by a vote 280-142 (with 73 Republicans joining Democrats) removed Section 1020y, eliminating NPDES relief from the House Farm Bill. Because of the strong support for Luna’s amendment and the narrower margin for getting a Farm Bill passed in the Senate, NPDES relief was not included in the Senate’s version.