The past year witnessed significant advancements in the realm of environmental law, and 2026 is poised to continue this trend. As we delve into the new year, several key environmental law issues are expected to take center stage, with the National Agricultural Law Center (NALC) keeping a close watch on these developments.
One of the most contentious issues is the definition of “Waters of the United States” (WOTUS) under the Clean Water Act (CWA). In mid-November, the Environmental Protection Agency (EPA) and the U.S. Army Corps of Engineers proposed a rule to revise the definition of WOTUS in alignment with the Supreme Court’s 2023 ruling in Sackett v. EPA. This ruling specified that WOTUS includes only waters that are “relatively permanent, standing or continuously flowing” and wetlands that have a “continuous surface connection” with such waters. The proposed rule limits the definition of WOTUS to traditionally navigable waters, their tributaries, and adjacent wetlands, as well as certain lakes and ponds. The public comment period for this proposal closed on January 5, 2026, and a final rule is anticipated later this year. Legal challenges are highly likely to follow, underscoring the ongoing debate over the scope of federal jurisdiction under the CWA.
Another critical area of focus is the Endangered Species Act (ESA). In November, the U.S. Fish and Wildlife Service (FWS) and the National Marine Fisheries Service (NMFS) issued four proposed rules aimed at modifying the implementation of the ESA. These proposals address the listing and delisting of species, the designation of critical habitat, and interagency consultation processes. Notably, the proposals seek to roll back the FWS’s Blanket 4(d) rule, which automatically grants threatened species full ESA protections, and to revise the criteria for excluding areas from critical habitat designation. The comment period for these proposals ended on December 22, 2025, and final rules are expected this year, with litigation likely to ensue.
Additionally, a final rule is expected to rescind the definition of “harm” within the context of a “take” under the ESA. The current definition, which includes “significant habitat modification or degradation,” has been in place for decades. The proposed rule aims to rescind this definition without providing a replacement, potentially leading to legal challenges once the rule is finalized.
The issue of Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) preemption will also remain a focal point in 2026. This debate centers on whether federal pesticide law preempts state tort liability claims, particularly in cases involving glyphosate, the active ingredient in Roundup. Bayer, the manufacturer of Roundup, argues that state failure-to-warn claims are preempted by FIFRA, which prohibits states from adding label language different from the EPA-approved version. Plaintiffs contend that these claims are not preempted because FIFRA bans the sale of pesticides without necessary health warnings. The Supreme Court may resolve this issue if it agrees to hear Monsanto v. Durnell, a case that could significantly impact ongoing pesticide injury claims nationwide. Meanwhile, several states are expected to introduce legislation to shield pesticide companies from liability by specifying that federally approved labels serve as a complete defense against failure-to-warn claims.
Pesticide labeling and regulation will also be of paramount importance in 2026. EPA is expected to continue developing its approach to integrating ESA and FIFRA responsibilities in pesticide registration, following the launch of its Insecticide Strategy in 2022. This year, the agency is anticipated to issue a draft Fungicide Strategy, which will likely include application restrictions to mitigate fungicide exposure to listed species. Additionally, final labels for three over-the-top dicamba products, which have been unavailable since a federal court vacated their registration in 2024, are expected to be released. These labels are crucial for the products’ availability during the 2026 growing season.
Several ongoing lawsuits challenging various pesticide labels will also garner attention. A challenge to EPA’s registration of Enlist One and Enlist Duo could test the agency’s Herbicide Strategy, which aims to reduce exposure to listed species through application restrictions. Furthermore, the Natural Resources Defense Council has petitioned a federal court to compel EPA to respond to a 2020 petition requesting changes to pesticide tolerances for neonicotinoid insecticides. This case could have long-term implications for the availability of neonicotinoids.
Lastly, the National Environmental Policy Act (NEPA) saw a major revision last year after federal courts determined that the Council on Environmental Quality (CEQ) lacked the authority to issue binding regulations