The last year saw significant developments in the arena of environmental law and 2026 is likely to bring more of the same. The following is an overview of some of the top environmental law issues that NALC will be watching in the coming year.
Waters of the United States
In mid-November, the Environmental Protection Agency (“EPA”) and the United States Army Corps of Engineers (“the Corps”) published a proposed rule to once again revise the Clean Water Act (“CWA”) definition of “waters of the United States,” or WOTUS. The term is critical to CWA implementation because only those waters and wetlands that fall under the definition of WOTUS are subject to the CWA’s permitting authority. According to EPA and the Corps, the latest proposal will bring the definition of WOTUS in-line with the Supreme Court’s 2023 ruling in Sackett v. EPA which held that WOTUS included only those waters which are “relatively permanent, standing or continuously flowing” and wetlands that “share a continuous surface connection” with such waters. To that end, the proposed definition would include only the following categories of waters as WOTUS: traditionally navigable waters which can be used to facilitate interstate or foreign commerce; impoundments of waters otherwise identified as a WOTUS; tributaries of traditionally navigable waters which are relatively permanent, standing, or continuously flowing; wetlands that share a continuous surface water connection with a traditionally navigable water or tributary; and lakes and ponds which are relatively permanent, standing or continuously flowing and which share a continuous surface connection with a traditionally navigable water or tributary.
A public comment period on the proposed rule closed on January 5, 2026. A final rule is expected sometime this year. It is highly likely that litigation over the rule will follow. To learn more about the proposed rule, click here.
Endangered Species Act
Also in November, the United States Fish and Wildlife Service (“FWS”) along with the National Marine Fisheries Service (“NMFS”) (collectively, “the Services”) issued four proposed rules that would make numerous changes to how the Endangered Species Act (“ESA”) is carried out. Specifically, the proposals would revise how both Services list and delist species, designate critical habitat for listed species, and conduct interagency consultation. The proposals would also roll back FWS’s Blanket 4(d) rule which allows the agency to automatically grant species listed as “threatened” complete ESA protection, and would revise how FWS determines whether an area should be excluded from critical habitat designation. A comment period for each of the four proposals closed on December 22, 2025. Final rules are expected sometime this year. Litigation is highly likely to follow. For further information, click here.
A final rule is also expected sometime this year to rescind the definition of “harm” within the context of a “take” under the ESA. When a species is listed for protection under the ESA, it becomes illegal to “take” that species with “take” broadly defined in the statute to cover a variety of activities including causing “harm” to the species. For decades, the Services have defined “harm” through their ESA regulations as “an act which actually kills or injures wildlife” providing that “such an act may include significant habitat modification or degradation[.]” 50 C.F.R. § 17.3. The proposed rule would rescind the definition without replacing it. A comment period on the proposal closed on May 19, 2025. It is likely that the rule will be challenged in court after it is finalized. Click here to learn more.
FIFRA Preemption
The question of whether federal pesticide law preempts state tort liability claims will continue to be top-of-mind in 2026 with various states expected to introduce liability shield legislation and a critical case pending before the Supreme Court. The issue stems from lawsuits filed by plaintiffs claiming that exposure to a pesticide product caused them to develop some sort of illness or injury. The best-known of these cases involve glyphosate, the active ingredient in the herbicide Roundup, which has faced a decade of legal challenges filed by plaintiffs who claim that Bayer, the manufacturer of Roundup, failed to warn consumers about the health risks of using its products. In response, Bayer and others have argued that the plaintiffs’ failure to warn claims should not be brought in the first place because they are preempted by the Federal Insecticide, Fungicide, and Rodenticide Act (“FIFRA”) which prohibits states from adding language to a federally registered pesticide label that is different from or in addition to the label language approved by EPA. In turn, the plaintiffs have argued that the failure to warn claims are not preempted by federal law because FIFRA bans the sale of pesticides which do not include necessary health warnings. An explanation of both arguments is available here.
The matter may be settled this year if the Supreme Court agrees to hear Monsanto v. Durnell which asks the Justices to provide their opinion on the preemption issue. While it is currently unclear whether the Court will take the case, a recently filed brief from the Office of the Solicitor General urges the Court not only to take up the matter but to rule that FIFRA preempts state law failure to warn claims. Whatever action the Court takes, it will likely impact thousands of on-going pesticide injury claims throughout the county. In the meantime, several states have sought to find their own solution to the matter by passing state legislation specifying that a federally approved pesticide label will be considered a complete defense to any failure to warn claims filed in that state. More states are expected to pursue this option in 2026. For more information on state efforts to limit liability for pesticide companies, click here.
Pesticide Labeling & Regulation
Along with the question of FIFRA preemption, various issues surrounding pesticide registration and labeling will be of importance in 2026. EPA is expected to continue developing and implementing the novel approach to meeting the agency’s ESA and FIFRA responsibilities when registering pesticides that was initially launched in 2022. While 2025 saw a finalization of EPA’s Insecticide Strategy, in 2026 the agency is expected to issue a draft version of its Fungicide Strategy. Like last year’s Insecticide Strategy and 2024’s Herbicide Strategy, the Fungicide Strategy is expected to identify various application restrictions that are intended to mitigate fungicide exposure to listed species. More information on the Insecticide Strategy is available here.
Also expected this year are final labels for three over-the-top dicamba products that have been unavailable since a federal court vacated previously registered labels for the products in February 2024. EPA published proposed labels for the products in July 2025 and stated an intention to make the products available for the 2026 growing season. Further information is available here. Several on-going lawsuits challenging various pesticide labels are also of interest going into 2026. A challenge to EPA’s decision to register Enlist One and Enlist Duo not only target the availability of those products, but could also be the first test of EPA’s Herbicide Strategy which adds application restrictions to herbicide labels in order to reduce exposure to listed species. More details are available here. Finally, the Natural Resources Defense Council has asked a federal court to compel EPA to respond to a 2020 petition submitted by the group asking the agency to make changes to the current pesticide tolerances for neonicotinoid insecticides. While the case is still in its early stages, it could have long-term implications for the availability of neonicotinoids. For more on that case, click here.
National Environmental Policy Act
Last year saw a major revision to one of the nation’s most prominent environmental laws after two different federal courts concluded that the Council on Environmental Quality (“CEQ”) did not have authority to issue binding regulations for the National Environmental Policy Act (“NEPA”). CEQ, which was created to administer NEPA, subsequently rescinded all of its NEPA-implementing regulations which had been in place since the late 1970s. At the same time, CEQ released a memorandum addressed to heads of federal departments and agencies on how to proceed with NEPA compliance, advising that agencies either revise their NEPA implementing procedures to conform with the statutory text of NEPA or to establish such procedures if the agency does not already have any in place. CEQ advised agencies to complete their NEPA process revisions by February 19, 2026, although it is not clear what would happen if an agency missed that deadline. Currently, some agencies, such as the Department of Interior, have begun rolling out their NEPA updates while other agencies, including EPA, have not. For further information, click here.
Colorado River
The Colorado River is one of the most important waterways in the Western United States. It spans across seven states and provides water to approximately 5.5 million acres of agricultural land and over 40 million people. Since the year 2000, the Colorado River has seen decreased flows due to prolonged drought and shifting hydrological conditions in the region. In 2007, the Bureau of Reclamation (“Reclamation”) which operates Lakes Powell and Mead, the two most important reservoirs on the Colorado River, adopted a set of operating guidelines intended to respond to water shortages. Those guidelines are set to expire this year and it is currently unclear how the Colorado River will operate post-2026. The seven states that rely on the river – Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming – have yet to reach a consensus decision on post-2026 management. For its part, Reclamation initiated a NEPA process to begin examining possible options for post-2026 management in 2023. While a complete draft of the NEPA document is not expected until sometime this year, a report issued by Reclamation in 2024 provides some insight into the options that the agency is considering. For water users in the region, 2026 will be a critical year for determining future management of the Colorado River. To learn more about the current state of the River and the options Reclamation is considering, click here.
PFAS
The legal and regulatory framework surrounding per- and polyfluoroalkyl substances (“PFAS”), also known as forever chemicals, will continue to develop throughout 2026 as agencies consider regulatory changes and plaintiffs seek redress from the courts. In September, EPA announced in a court filing that it intends to roll back Safe Drinking Water Act regulations adopted in April 2024 which designated six PFAS chemicals as drinking water contaminants for the first time. The roll back would apply to only four of the six PFAS; designations for perfluorooctanoic acid (“PFOA”) and perfluorooctanesulfonic acid (“PFOS”) would remain untouched. Because EPA has voluntarily asked a court to vacate this rule, it is unclear whether or when the request may be granted. While EPA is seeking to reverse SDWA regulations for PFAS, it has stated that it intends to keep intact its May 2024 decision to declare PFOA and PFOS as hazardous substances under the Comprehensive Environmental Response, Compensation, and Liability Act. Further information on that decision is available here.
In late September, a federal court in the District of Columbia issued an order to dismiss a case filed by farmers and ranchers in Texas against EPA for the agency’s alleged failure to regulate PFAS under the CWA. Specifically, the farmers claimed that EPA had violated the CWA by failing to identify and regulate PFAS pollutants present in biosolids, a term used to refer to the solid waste filtered from wastewater treatment plants that is commonly used as fertilizer on farms after being treated to remove toxic contaminants. While the court dismissed the case, concluding that EPA had not violated the CWA, it left open the possibility for re-filing and noted that the plaintiffs could petition EPA to regulate PFAS pollutants. However, the plaintiffs have appealed that decision to the D.C. Circuit Court of Appeals and the case is on-going. To learn more about the litigation, click here.
Conclusion
The previous years have seen several developments in the world of environmental law that have had implications for agriculture and 2026 will be no different. NALC will be tracking the above topics and more as the year progresses.
For more NALC resources on environmental law, click here.