Business & Policy Environmental Policy What Is the Clean Water Act? It protects the quality of U.S. waters and has undergone several changes since 1972. By Liz Allen Liz Allen LinkedIn Twitter Writer College of William & Mary Northeastern University Liz is a marine biologist, environmental regulation specialist, and science writer. She has previously studied Antarctic fish, seaweed, and marine coastal ecology. Learn about our editorial process Updated August 11, 2022 Share Twitter Pinterest Email Kleber Kihara / EyeEm / Getty Images Business & Policy Corporate Responsibility Environmental Policy Economics Food Issues In This Article Expand Pollution Problems Before the Clean Water Act How the Clean Water Act Became Law What Does the Clean Water Act Do? Impact of the 2015 Clean Water Rule Current Status of the Clean Water Act The Clean Water Act is the primary federal law protecting the quality of the U.S. surface waters, including lakes, rivers, and coastal wetlands. The legislation was enacted in 1972 after being vetoed by President Nixon. Since then, the legislation has gone through many iterations. Pollution Problems Before the Clean Water Act Before the Clean Water Act, U.S. waterways were famously filthy. Untreated and undertreated wastewater filled nearby cities with the smell of human waste. Clouds of soap suds slid down waterways, and industrial chemicals were released into the waterways supplying drinking water. In 1948, President Eisenhower signed into law the Federal Pollution Control Act. This legislation funded the study and management of water pollution. However, when faced with a bill meant to strengthen this act, Eisenhower issued a veto because he considered water pollution to be a local issue and urged state governments to take their share of the responsibility. Yet just a year later, when President John F. Kennedy took office, the federal bill was signed into law. Unfortunately, even the strengthened Federal Pollution Control Act was far from enough to curb the country’s water pollution problem. Most water quality management remained under the responsibility of individual states. To avoid strict pollution requirements, companies could move to states with more lenient regulations. However, the interconnectedness of waterways did not retain pollution within state lines, so U.S. waters continued to suffer from severe pollution. How the Clean Water Act Became Law Following a blowout of Union Oil’s Platform A on January 28, 1969, 3.2 million gallons of crude oil spilled into the coastal waters of Santa Barbara, California. The environmentally catastrophic oil spill was blamed on inadequate safety precautions taken by the oil company. Just a few months later, the oil-slicked surface of Cleveland’s Cuyahoga River lit on fire. While this was not the first time the Cuyahoga had caught fire, the blaze is credited with inspiring bipartisan support for cleaning up the country’s waterways. Over the following three years, U.S. lawmakers drafted additional amendments to strengthen the Federal Water Pollution Control Act and establish the federal Environmental Protection Agency (EPA). Despite the consensus and then-President Nixon’s support of the amendment’s environmental aims, Nixon vetoed the bill over its $24 billion price tag. Nonetheless, votes from the House and the Senate were enough to override the veto and sign the amendments into law. This strengthened version of the Federal Water Pollution Control Act became known as the Clean Water Act. What Does the Clean Water Act Do? Broadly, the Clean Water Act regulates the release of pollutants into waters of the United States. The EPA oversees the Clean Water Act but delegates portions of the legislation’s mandate to State and federal agencies. Most of this oversight responsibility ultimately lies with the U.S. Army Corps of Engineers and state regulators. Protected Waters Under the Law The waters protected under the Clean Water Act have changed in the decades following the law’s passage. The original act defines waters of the United States as navigable waterways — rivers, streams, lakes, and bays, for instance, through which a boat can operate, as well as isolated wetlands adjacent to these waterways. The law does not include protections for groundwater. Under the Clean Water Act, virtually any work within these so-called jurisdictional waters requires approval from a federal or state agency. For example, the installation of a dock or mooring buoy to waters of the United States would be considered “fill material” under the Clean Water Act, requiring a permit. Should impacts to the waterway be deemed overly severe, a permit may be denied to protect the waters' integrity. The National Pollutant Discharge Elimination System The Clean Water Act also established a system for regulating the release of pollutants into waters of the United States: The National Pollutant Discharge Elimination System, or NPDES. The NPDES program is typically overseen by individual states, tribes, and territorial governments at the discretion of the EPA. Through the NPDES program, facilities that need to release pollutants into regulated waters are legally required to obtain a permit authorizing the discharges. For example, a city’s sewage treatment facility is required to obtain an NPDES permit to release treated wastewater into the environment. Through the NPDES permit, monitoring requirements and pollution limits are often stipulated. In other words, while receipt of an NPDES permit authorizes the release of pollutants into federal waters, the permit does not allow the unlimited pollution of a waterway. Instead, through the NPDES program, the Clean Water Act manages the extent to which a party may pollute and provides the authority to halt a facility’s release of pollutants if the terms of the NPDES permit are breached. While the NPDES permit program regulates point source pollutants, or pollutants coming from a single, identifiable origin, the Clean Water Act also recognizes the importance of nonpoint source pollutants, or those originating in small quantities from many locations. These nonpoint source contaminants can still end up in our waterways, where they accumulate and cause harm both to the environment and to our sources of drinking water. For example, all the cars on the road release small amounts of oil onto the roadways. When it rains, water washes the roads, carrying oil to surrounding streams. While each car may release a negligible amount of oil, the accumulation of oil in waterways can have a significant impact on the environment. Similarly, the use of fertilizers on a single lawn may seem negligible, but the accumulation of these nutrients can cause harmful algal blooms in downstream waterways. Unlike point source pollutants, like those coming from wastewater treatment plants or factories, these pervasive nonpoint source pollutants are not managed under the Clean Water Act by specific regulations. Instead, the law provides federal funding for states to each implement nonpoint source pollutant reduction programs of their own. Despite the funding provided under the Clean Water Act, nonpoint source pollutants remain the leading cause of water quality problems today. The SWANCC Decision In the 1990s, the Solid Waste Agency of Northern Cook County (SWANCC) sought to create a landfill from land used for sand and gravel mining decades earlier. Despite the previous industrial use of the land, wetlands used as breeding grounds for the great blue heron, along with other migratory birds, developed in the intervening years. The wetlands were not directly adjacent to a navigable waterway, so they were not explicitly protected under the Clean Water Act. Nonetheless, the Army Corps deemed the wetlands as ‘jurisdictional’ based on their Migratory Bird Rule. Since many migratory birds cross state lines, the use of wetlands by these birds, according to the rule, connects these wetlands to navigable waters, extending Clean Water Act protections to these otherwise isolated areas. The Army Corps ultimately denied SWANCC the permit needed under the Clean Water Act for their landfill development project based on the project’s anticipated impacts to migratory birds. This was not the first time the Army Corps had applied the Migratory Bird Rule to apply Clean Water Act protections to isolated wetlands, nor was it the first time the rule’s use was challenged. However, lower courts ruled in favor of the Army Corps, upholding the rule. Nonetheless, in 2001 the case between SWANCC and the U.S. Army Corps of Engineers made its way to the Supreme Court. At the heart of the case was the definition of ‘navigable waters’ under the Clean Water Act. The Supreme Court ruled in a 5-4 decision that the Army Corps’ Migratory Bird Rule was not supported under the Clean Water Act. Many legal scholars found this ruling to be in direct opposition to previous decisions issued by the Supreme Court, which found it to be Congress’s intent that the Clean Water Act’s jurisdiction over ‘navigable waters’ receive the broadest interpretation possible. Through the Supreme Court’s ‘SWANCC Decision’, a significant portion of U.S. wetlands lost coverage under the Clean Water Act. However, the uncertainty rendered by the SWANCC Decision made it impossible to determine the true impact of the ruling. The Rapanos Decision Just five years later, the Supreme Court faced another landmark case that questioned the protection of isolated wetlands under the Clean Water Act: Rapanos v. United States. The appellant, John Rapanos, filled 54 acres of wetlands on his property with sand in preparation for construction of a mall and residential homes. Rapanos did not file for a permit with the Army Corps before burying the wetlands because, in his view, the wetlands on his property did not constitute Waters of the United States because they were isolated and 20 miles from any navigable waterway. The United States pursued Rapanos’ action as a violation of the Clean Water Act. Unlike the SWANCC case, the Supreme Court was unable to issue a decision on Rapanos v. United States. Nonetheless, Justice Kennedy’s opinion established important precedent for interpretation of the Clean Water Act for the next decade. Kennedy deemed wetlands with a “significant nexus” to downstream navigable waters protected under the Clean Water Act. In Kennedy’s opinion, wetlands must “significantly affect the chemical, physical, and biological integrity” of traditionally navigable waters to have a significant nexus. Kennedy’s opinion left room for isolated wetlands to garner protection under the Clean Water Act under certain circumstances, but the EPA and the Army Corps struggled to issue clear guidance for regulators to issue consistent determinations based on the Rapanos Decision. Instead, the “significant nexus” standard caused many wetlands and similar isolated water features to require an individual, case-by-case analysis. Impact of the 2015 Clean Water Rule Under the Obama administration, ambiguity resulting from the Rapanos Decision continued to leave many wetlands unprotected under the Clean Water Act. The 2015 Clean Water Rule aimed to clarify and expand the waters eligible for protection under the Clean Water Act by providing specific guidance on the tributaries and adjacent waters protected by the act. According to the Clean Water Rule, upstream waters with a clear bed, bank, and ordinary high water mark are protected. Furthermore, the Clean Water Rule explicitly extended protections to specific “regional water treasures” shown to impact downstream water health, such as California’s vernal pools and Texas’ coastal prairie wetlands. Current Status of the Clean Water Act Despite strong support from environmental activists, legislators, and scientists, the Obama administration’s Clean Water Rule received strong pushback by those who viewed the rule as a form of government overreach. In 2017, the Trump administration formally announced its plan to review the Obama-era Clean Water Rule with the intent of revising or rescinding the rule’s protections. The Clean Water Rule was officially suspended in 2018 and repealed in 2019. The Trump administration issued a replacement rule to roll back the Clean Water Act’s protections further, which was quickly labeled by environmental advocates as the “Dirty Water Rule.” Despite efforts to prevent the rule from taking hold, the Trump administration’s “Navigable Waters Protection Rule” went into effect on June 22, 2020. The Rule immediately faced legal challenges around the country, which are expected to continue into 2021. So far, only Colorado has successfully prevented the Trump administration’s rule from taking hold. The Biden administration is expected to undo Trump's sweeping regulatory rollbacks, including recent changes to the interpretation of the Clean Water Act. However, instating a new rule to replace Trump's Navigable Waters Protection Rule will require input from both the EPA and the U.S. Army Corps of Engineers. Given the coordination needed, it may be a year or two before changes are made. Nonetheless, changes are apparent already. On January 7, 2021, the EPA finalized its "Strengthening Transparency in Regulatory Science" rule. The new rule requires a more data-driven approach be used in the development of new environmental regulations, such as future decisions about the Clean Water Act. Key Takeaways The Clean Water Act is the federal law protecting the nation's waterways.Based on various court decisions, the list of waters protected by the Clean Water Act has changed several times since the law was passed.The Obama-era Clean Water Rule clarified ambiguity resulting from the Rapanos Decision, a key Supreme Court case centered on the Clean Water Act.The Trump administration repealed the Clean Water Rule and replaced it with the Navigable Waters Protection Rule, which significantly decreased the waters protected under the Clean Water Act. View Article Sources “Water Quality: A Half Century of Progress.” EPA Alumni Association. National Research Council. Identifying Future Drinking Water Contaminants. 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Mank, Bradford. “Implementing Rapanos - Will Justice Kennedy 's Significant Nexus Test Provide a Workable Standard for Lower Courts, Regulators and Developers?” University of Cincinnati College of Law Scholarship and Publications. 2007. “Clean Water Rule: Definition of Waters of the United States.” Federal Register. “Commitment to Clean Water.” The White House of President Barack Obama. “Technical Questions and Answers For Implementation of the Clean Water Rule.” U.S. Environmental Protection Agency. “Fact Sheet: Clean Water Rule.” U.S. Environmental Protection Agency. Richards, Ryan. “Debunking the Trump Administration’s New Water Rule.” Center for American Progress. Devine, Jon. “Trump’s Dirty Water Rule: EPA Ignorance is Polluters’ Bliss.” Natural Resources Defense Council. “The Navigable Waters Protection Rule: Definition of Waters of the United States.” Federal Register, vol. 85, no. 77, 21 April 2020. “Strengthening Transparency in Regulatory Science.” Federal Register.