Water contamination: Rollback of the Clean Water Act (W.O.T.U.S.)

Waters of the U.S. and Non-Jurisdictional/Excluded Waters

      Water contamination has become one of the most important environmental concerns in the United States due to its direct impact on public health, ecosystems, and economic activities. The federal government has historically played a major role in regulating water pollution through environmental legislation and monitoring systems established by the Environmental Protection Agency (EPA). One of the most significant environmental laws in the country is the Clean Water Act, enacted in 1972 with the objective of restoring and maintaining the chemical, physical, and biological integrity of the nation’s waters. According to the EPA, the law created a federal framework to regulate pollutant discharges into U.S. waters and established water quality standards to reduce contamination. Furthermore, according to the EPA, federal compliance monitoring systems were developed to supervise industrial and agricultural activities that could negatively affect water quality.

      Within this framework, the concept of “Waters of the United States” (WOTUS) became essential because it defines which bodies of water receive federal protection under the Clean Water Act. According to the EPA, WOTUS plays a central role in determining the scope of federal jurisdiction over wetlands, tributaries, and other interconnected water systems. During the administration of Barack Obama, the WOTUS rule expanded protections significantly to influence larger water systems. This preventive approach aimed to reduce pollution risks before contamination could spread into interconnected ecosystems and drinking water sources. Additionally, Bowers and Gatz (2025), highlight that these protections reflected broader federal authority over adjacent wetlands and tributaries connected to navigable waters.

    Nonetheless, the administration of Donald Trump adopted a deregulatory environmental agenda focused on reducing federal oversight and promoting economic growth. Through the replacement of WOTUS with the Navigable Waters Protection Rule in 2020, the Trump administration narrowed the definition of federally protected waters, excluding several wetlands and temporary streams from regulation. Critics argued that these changes weakened environmental safeguards and increased the possibility of water contamination from industrial and agricultural activities. Therefore, it is important to explore how the rollback of the WOTUS rule under the Trump administration increased the risk of water contamination in the United States, reflecting a broader shift in environmental governance in which economic priorities increasingly outweighed federal environmental protections.

        In this context, it is important to mention how WOTUS was before Donald Trump. In this regard before Trump’s administration, the Obama administration introduced the WOTUS Rule (“Waters of the United States”) in 2015 as part of the Clean Water Rule. The purpose of this regulation was to clarify which bodies of water were protected under the Clean Water Act of 1972. For many years, there had been legal uncertainty after several Supreme Court decisions created confusion about federal jurisdiction over certain waterways. The rule was developed by the U.S. Environmental Protection Agency (EPA) and the U.S. Army Corps of Engineers (EPA, n.d).

        Under the Obama administration, WOTUS expanded federal protection beyond large rivers and lakes to include smaller streams, wetlands, and indirect water sources connected to larger aquatic systems. These included seasonal streams, tributaries, and wetlands located near rivers. According to the Environmental Protection Agency (EPA, n.d), even small or isolated water bodies could significantly affect the quality of downstream water because they filter pollutants, reduce flooding, and support ecosystems. Therefore, protecting only major rivers was considered insufficient.

      A key idea behind the WOTUS Rule was prevention. The Obama administration believed that environmental policy should stop pollution before it reached major drinking water supplies. Pollution often begins in small waterways or wetlands and later spreads into larger rivers and lakes. The regulation established categories of waters that were automatically protected and others that required case-by-case analysis to determine whether they had a “significant nexus” to larger waterways. By regulating these areas, the government hoped to reduce contamination caused by industrial waste, construction, agricultural chemicals, and other human activities. (EPA, n.d).

      The rule was also supported by scientific research. The EPA stated that more than 1,200 peer-reviewed studies demonstrated the important connection between small streams, wetlands, and the health of larger water systems. Because of this scientific evidence, the administration argued that broader federal protection was necessary to maintain clean and safe water across the United States.

Trump orders review of Obama rule protecting small streams

        

         The policy changes under the administration of Donald Trump focused on reducing federal control over water regulation. In 2020, the Waters of the United States (WOTUS) rule was replaced by the Navigable Waters Protection Rule (NWPR), which redefined which waters are protected under the Clean Water Act. This change reduced the number of water bodies covered by federal protection and limited the scope of national regulation.

      A key aspect of this reform was the exclusion of certain types of waters that had previously been protected. The NWPR removed isolated wetlands and ephemeral streams from federal jurisdiction. These are water bodies that are not always connected to larger rivers or only appear during rainfall. According to Santrock (2021), this redefinition significantly reduced federal authority over water resources. The government justified these changes by arguing that earlier regulations were too strict and limited economic activity. Reducing “overregulation” was presented as a way to promote economic growth, especially in sectors such as agriculture, construction, and energy. As Perls (2020) explains, this reflects a broader effort to reduce federal intervention and support development.

      However, these changes also created important challenges. Scientific research shows that even small or temporary water sources contribute to overall water quality (Adler, 2015). By excluding them, the policy weakened existing protections. In addition, reducing federal oversight increased the role of state governments in regulating water resources. Under the system of cooperative federalism, federal standards are meant to ensure consistent protection, but as Hearne (2020) notes, when federal control is reduced, states take on more responsibility. This can lead to differences in how regulations are applied. As a result, some states maintain stronger protections while others do not, creating unequal levels of environmental protection across the country. Morrison (2018) highlights that this has produced a more fragmented regulatory system, where protections vary depending on the state.

        Regarding the increased Pollution Risk, the Supreme Court’s decision in Sackett v. EPA significantly narrowed the scope of federal jurisdiction under the Clean Water Act (CWA), potentially increasing pollution risks by excluding waters previously protected for decades. By adopting the "relatively permanent" test, the Court excluded ephemeral waters and wetlands that lack a continuous surface connection to traditional navigable waters. Consequently, fewer wetlands are protected today than under any regulatory framework implemented since the 1970s. Current 2025 guidance further clarifies that wetlands separated by natural or artificial barriers, such as dikes, berms, or dunes, are generally no longer jurisdictional. Additionally, federal agencies have rescinded prior guidance that allowed "discrete features"(such as non-jurisdictional pipes, culverts, or ditches) to establish a jurisdictional surface connection, further limiting the number of water bodies subject to federal pollution controls.

     About the agricultural and Industrial Impact, recent regulatory revisions and guidance from the second Trump Administration aim to reduce "red-tape" and lower permitting costs for businesses, industry, and the agricultural sector. The CWA regulates point source discharges through the National Pollutant Discharge Elimination System (NPDES), which applies to industrial facilities and Concentrated Animal Feeding Operations (CAFOs) discharging into "waters of the United States" (WOTUS). Under the narrowed Sackett standard, many industrial and agricultural activities may no longer require these federal permits if the affected waters are deemed non-jurisdictional. Furthermore, "prior converted cropland" is explicitly excluded from WOTUS jurisdiction, an exemption that only ceases if the land changes use and is no longer available for agricultural production. In the 119th Congress, legislative efforts like the Farmers Freedom Act of 2025 seek to further codify these agricultural exclusions to provide permanent regulatory relief to the farming sector.

           Concerning the fragmentation of Environmental Protection, the regulation of U.S. water resources currently exists as a "patchwork" of different legal regimes due to ongoing litigation and shifting federal rules. As of June 2025, 24 states follow the 2023 WOTUS Rule (as amended by the Conforming Rule), while 26 states operate under the pre-2015 regulatory regime interpreted consistent with the Sackett decision. This fragmentation creates greater state-level divergence in environmental protection across the country. While the CWA allows states to implement more stringent protections than the federal government, several states have enacted laws barring their agencies from promulgating regulations beyond federal requirements, meaning a narrowed federal definition automatically reduces protections in those areas. Conversely, other states have responded to the Sackett ruling by expanding their own state-level protections for wetlands and streams that lost federal oversight.

Farmland in the United States

          The rollback of the WOTUS rule under the Trump administration demonstrates that these changes were not solely environmental decisions, but also economic and ideological ones. The Trump administration argued that previous federal regulations imposed excessive burdens on industries, farmers, and landowners, limiting economic development and increasing administrative costs. By replacing WOTUS with the Navigable Waters Protection Rule (NWPR), the government sought to reduce federal intervention and promote economic growth through deregulation and streamlined permitting processes.

            However, these changes also highlighted a significant conflict between economic growth and environmental sustainability. While proponents of the rollback argued that deregulation was necessary to boost productivity and reduce “over-regulation,” critics argued that weakening federal protections increased the risks of water pollution and reduced the Clean Water Act’s preventative capacity. The scientific evidence previously used to support WOTUS demonstrated that wetlands, tributaries, and ephemeral streams play a vital role in filtering pollutants and protecting interconnected ecosystems. Therefore, excluding these waters from federal jurisdiction weakened the overall environmental protection system.

      The rollback also reflected deeper ideological differences regarding the role of government in environmental governance. The Trump administration promoted a more conservative, market-oriented approach, based on less federal authority and greater state responsibility. In contrast, the Obama administration championed a preventative environmental model in which strong federal regulation was necessary to protect interconnected water systems across the country. As a result, reduced federal oversight created a fragmented regulatory framework where environmental protections vary considerably from state to state.

      In conclusion, the rollback of WOTUS demonstrates how environmental deregulation can weaken water protection systems, increasing the risks of pollution and disproportionately impacting the most vulnerable communities. While the policy aimed to stimulate economic growth and reduce federal control, it also highlighted the environmental consequences of prioritizing economic interests over long-term sustainability and consistent national environmental protection.

References:

                                                                  

Adler, R. W. (2015). US Environmental Protection Agency’s new Waters of the United States Rule: connecting law and science. Freshwater Science, 34(4), 1595-1600. https://www.journals.uchicago.edu/doi/pdf/10.1086/684002

Bowers, K. R., & Gatz, L. (2025). Waters of the United States (WOTUS): Frequently asked questions about the scope of the Clean Water Act. Congressional Research Service. https://www.congress.gov/crs-product/R47408

Hearne, R. (2020). Cooperative Federalism and the Clean Water Act: Implementation in Minnesota and North Dakota. Journal of Natural Resources Policy Research, 10(1), 1-21. https://drive.google.com/file/d/12YdElA7Js0714MxiXJ7uSSus-zlmyYA4/view

Morrison, C. (2018). California's Response to the Trumpian Rollback of Wetland Protections under the Clean Water Act. Hastings Envt'l LJ, 24, 129. https://repository.uclawsf.edu/cgi/viewcontent.cgi?article=1037&context=hastings_environmental_law_journal

Perls, H. (2020). Deconstructing environmental deregulation under the Trump administration. Vt. L. Rev., 45, 591. https://lawreview.vermontlaw.edu/wp-content/uploads/2021/07/05_Perls_Final.pdf

Santrock, J. (2021). Review of the History of the Clean Water Act and Critique of the 2020 Navigable Waters Protection Rule (Master's thesis, University of Georgia). https://openscholar.uga.edu/record/5203/files/Santrock_Julianna_R_202105_MS.pdf

U.S. Environmental Protection Agency. (n. d.). What the Clean Water Rule Does | Clean Water Rule. https://archive.epa.gov/epa/cleanwaterrule/what-clean-water-rule-does.html

U.S. Environmental Protection Agency. (n.d). About Waters of the United States. https://www.epa.gov/wotus/about-waters-united-states

U.S. Environmental Protection Agency. (n.d). Clean Water Act compliance monitoring. https://www.epa.gov/compliance/clean-water-act-cwa-compliance-monitoring

U.S. Environmental Protection Agency. (n.d). History of the Clean Water Act. https://www.epa.gov/laws-regulations/history-clean-water-act

U.S. Environmental Protection Agency. (n.d). Summary of the Clean Water Act. https://www.epa.gov/laws-regulations/summary-clean-water-act