Dan Buckley
Associate Editor
Loyola University Chicago School of Law, JD 2026
A second Trump administration is sure to challenge a variety of clean water and drinking water regulations, as evidenced by various policies proposed by the Heritage Foundation’s Project 2025. President-elect Donald Trump has distanced himself politically from the project but it remains relevant as he continues to surround himself with many of its authors. Many water lawyers and environmental advocates thus expect a second Trump administration to continue the federal water deregulation efforts seen in his first administration. Specifically, President-elect Trump will likely challenge and potentially repeal both the Biden Administration’s “waters of the US” (WOTUS) rule and its Section 401 state certification rule. These moves are likely to be compounded by other ecological regulation rollbacks and further exacerbate an already worsening climate crisis in the United States.
The Clean Water Act: WOTUS and state certification rules today
The Clean Water Act (CWA) began as the Federal Water Pollution Control Act, originally enacted in 1948, and became known as the CWA after it was significantly amended and expanded in 1972. The CWA sets the rules and structure for how the federal government regulates pollution in the “waters of the United States” as well as water quality standards broadly. The U.S. Environmental Protection Agency (EPA) is the primary administrative body that administers the laws and regulations created by the CWA and works in coordination with state governments and regulatory bodies.
The Biden administration’s WOTUS rule came in response to the Supreme Court’s 2023 ruling in Sackett v. EPA, which narrowed the interpretation of the phrase “waters of the US” and thereby lifted Clean Water Act regulations on many wetlands. The WOTUS rule refers to the regulatory definition of what is covered by the CWA phrase “waters of the United States” and thus mandates what is protected by federal regulations. The Biden administration broadened this definition by reverting the WOTUS rule to its 2015 standard after then-President Trump changed the rule in 2019 to drastically narrow the definition.
The Biden administration’s Clean Water Act Section 401 state certification rule grants U.S. States and Native American tribes the power to stop large interstate infrastructure projects that could be a risk to polluting waters within their borders. Under the Biden rule, States and Native American tribes can block projects over broad concerns related to their water resources, including impacts on water quality. This rule reversed the 2020 Trump administration’s rule that limited state’s ability to review projects except in cases of direct discharges of pollution. The Biden state certification rule was further tested when eleven Republican-led states and energy groups came together to block the bill, but their attempt to halt implementation of the rule was denied by U.S. District Judge James Cain earlier this year.
Changes in a second Trump administration
On the campaign trail, President-elect Donald Trump pledged to “kill” and “cancel” EPA rules and regulations as well as “restore U.S. energy dominance.” In his first administration, he rolled back over 100 environmental rules and regulations but many of these were restored or strengthened by President Joe Biden. The second Trump administration is expected to continue this with a focus on deregulation across the board including many water-related rules and regulations.
The incoming administration is likely to revert the WOTUS rule to its standard under the first Trump administration by limiting the scope of the Clean Water Act and making it easier for companies to develop and build on areas like wetlands and marshes. Additionally, the administration will likely repeal the Section 401 state certification rule, taking back the power granted to states to veto potentially ecologically harmful interstate projects. In the Project 2025 handbook, Mandy Gunasekara, the chief of staff at the EPA in the first Trump Administration, recommends massive cuts to the agency across many of its programs. Deregulations and loss of EPA funding will make enforcing environmental protections much more difficult across the country and embolden corporations to cut costs by removing ecological considerations.
Potential future impacts and mitigation efforts
The abovementioned rules are just two examples of many environmentally protective rules and regulations expected to be repealed or changed in the incoming Donald Trump administration. States must prepare for this now by tightening their regulations to prevent private companies from harming our native lands and waterways. Unfortunately, our water aquifers and waterways don’t observe these state boundaries, and pollution in one part of the system affects the whole. States, and cities like Chicago, must do what they can to install increased environmental protections and decrease their pollution to help offset this and protect their natural resources.