Clean Water Act

Clean Water ActThe federal Clean Water Act (CWA) is the main piece of federal legislation that protects the Nation's waters. Within the CWA, there are a number of sections that specifically address protection or regulation of wetlands. For example, Section 303 addresses water quality standards; Section 401 includes 401 Certification—to condition permits; Section 402 addresses the National Pollutant Discharge Elimination System (NPDES); and Section 404 includes the dredge and fill permitting program as well as State Assumption.

The Clean Water Act was weakened by the U.S. Supreme Court after the split decision known as the Rapanos and Carabell Decision in 2006, which followed another complex debate known as the SWANCC Decision in 2001. In 2015, under the Obama Administration, the U.S. Environmental Protection Agency (EPA) and the U.S. Army Corps of Engineers (Corps) released the Clean Water Rule to clarify jurisdiction over streams and wetlands. Legal challenges immediately ensued which held up the rule in court. In fact, 28 states successfully sought injunctions to block enforcement of the 2015 WOTUS Rule in federal courts around the country. The result was that 28 states ended up reverting to the pre-2015 definition of “waters of the Unites States” (WOTUS) and 22 states remained under the new 2015 WOTUS Rule. 

On February 28, 2017, President Trump issued a Presidential Executive Order entitled “Executive Order on Restoring the Rule of Law, Federalism, and Economic Growth by Reviewing the ‘Waters of the United States’ Rule” which directed the EPA and the Department of the Army to review the 2015 Rule defining WOTUS for consistency with the new Administration’s priorities and publish for notice and comment a proposed rule rescinding or revising the 2015 Rule, as appropriate and consistent with the law. Further, the Order directed the agencies to consider interpreting the term “navigable waters,” as defined in 33 U.S.C. 1362(7), in a manner consistent with the opinion of Justice Antonin Scalia in Rapanos v. United States, 547 U.S. 715 (2006) whereas previous to the 2015 Rule, the Kennedy opinion had prevailed, using the significant nexus test.

On October 22, 2019, the EPA and the Corps published a final rule (Step One) to repeal the 2015 Rule defining “waters of the United States” and re-codify the regulatory text that existed prior to the 2015 Rule. The final Step One rule became effective on December 23, 2019. Read the final Step One rule.

On January 23, 2020, the EPA and the Corps finalized the Navigable Waters Protection Rule (Step Two) to redefine “waters of the United States” (WOTUS). The Step One rule was then replaced by the Navigable Waters Protection Rule (NWPR) when it was published in the Federal Register on April 21, 2020. The final rule became effective on June 22, 2020. Factsheets on the NWPR are available here.

On June 9, 2021, EPA and Army Corps announced their intent to revise the definition of WOTUS through a process of two rulemakings. A foundational rule would first restore the pre-2015 definition consistent with relevant Supreme Court decisions, followed by a second rulemaking to further refine the definition. EPA and Army Corps have solicited pre-proposal feedback and public engagement on implementation and issues associated with WOTUS. More information is available here.

On August 30, 2021, the U.S. District Court for the District Court of Arizona in Pasqua Yaqui Tribe v EPA remanded and vacated the Navigable Waters Protection Rule. Because the order does not limit vacatur of the NWPR to Arizona, attorneys litigating WOTUS issues interpret the order as national in scope but expect the Dept. of Justice will ask for clarification on that point. The order can be seen here. The District Court noted that whether an agency action should be vacated depends on how serious the agency’s errors are and how disruptive the consequences are of an interim change that may itself be changed. The Court concluded that the agency errors were serious and have substantial disruptive environmental consequences.

Throughout the years and all of the legal challenges beginning in 2001 and earlier, the Association of State Wetland Managers has worked to stay abreast of potential changes in jurisdiction and practical application of the Clean Water Act in order to keep state and tribal wetland program managers prepared and equipped to navigate any regulatory changes or impacts to their programs.

To view past recorded webinars regarding the Clean Water Act, legal challenges and the Clean Water Rule, click here.

To find information about future webinars regarding the Clean Water Act and policy developments, click here.

Information Regarding Intent to Replace the Navigable Waters Protection Rule

Solicitation of pre-proposal feedback from EPA and Army Corps (August 4, 2021) includes several requests for information, among them any “relevant literature that has been published since the 2015 Connectivity Report.” This will help the Agencies identify relevant science related to how streams, wetlands, lakes and ponds restore and maintain chemical, physical, and biological integrity of the nation’s waters.

To support the Agencies’ effort to identify relevant connectivity literature and as a public resource, ASWM has compiled a reference list, available here.

Disclaimer: ASWM has not reviewed or vetted these references and is providing them strictly as a courtesy. To recommend additions, please contact Audra Martin ().

Actions and Information Regarding The Navigable Waters Protection Rule 

Lawsuits Filed in Response to Publication of the Navigable Waters Protection Rule

Summaries of Significant Clean Water Act Court Decisions

United States v. Riverside Bayview Homes, 474 U.S. 121 (1985)

A developer challenged the government’s determination that groundwater fed wetlands, adjacent to Black Creek, a navigable waterway, in the Lake St. Clair area of Michigan, were “waters of the United States” (WOTUS). The Supreme Court, in a unanimous decision, held that adjacent wetlands, in this case the hydric soils and hydrophitic vegetation of which extended beyond the wetlands on the developer’s property, were WOTUS. This definition of WOTUS was broader than “navigable waters,” because “protection of aquatic ecosystems, Congress recognized, demanded broad federal authority to control pollution”. The court also noted that even wetlands that are not flooded by adjacent waters may still drain into those waters, serving to filter and purify water, as well as slowing the flow of surface runoff into lakes, rivers, and streams.

Solid Waste Agency of Northern Cook County v. US (SWANCC), 531 U.S. 159 (2001)

A landfill operator challenged the government’s determination that ponds in an abandoned sand and gravel pit site were jurisdictional based on use by migratory birds under the so-called ‘Migratory Bird Rule.’ The Supreme Court, in a 5 to 4 decision, held that isolated, non-navigable, intrastate waters used by migratory birds as habitat are not waters of the United States (WOTUS). The Government’s argument that the ‘Migratory Bird Rule” falls within Congress’ power to regulate intrastate activities that substantially affect interstate commerce, raises significant constitutional questions, yet there is nothing approaching a clear statement from Congress that it intended to reach abandoned sand and gravel pits. “The grant of authority of Congress under the Commerce Clause, though broad, is not unlimited.”

Rapanos v. United States, 547 S.Ct. 715 (2006)

A Michigan developer challenged the government’s enforcement action for placing fill in wetlands that were hydrologically connected by surface connection to tributaries of navigable waters. The four justice plurality decision, written by Justice Scalia, held that “waters of the United States” (WOTUS) includes only those relatively permanent, standing or continuously flowing bodies of water “forming geographic features” that are described in ordinary parlance as ‘streams, rivers and lakes, and does not include channels through which water flows intermittently or ephemerally, or channels that periodically provide drainage for rainfall. While four other justices wrote dissenting opinions, one justice, Justice Kennedy, wrote a concurring opinion, which has become the “the significant nexus” test. According to Justice Kennedy, wetlands possess the requisite nexus, and thus are navigable waters, “if the wetlands, either alone or in combination with similarly situated lands in the region, significantly affect the chemical, physical, and biological integrity of other covered waters more readily understood as navigable. Since 2006, Rapanos has and will continue to influence wetlands judicial decisions as well as agency rulemaking.

Sackett v. EPA, 132 S.Ct. 1367 (2012)

The Sacketts owned a residential site in Idaho that contained wetlands separated from Priest Lake by several lots containing permanent structures. The government determined that the wetlands were adjacent, jurisdictional wetlands. When the Sacketts filled the one half acre of wetlands, the EPA sent them a compliance order, and denied the Sacketts request for an administrative hearing. This was in accordance with a federal regulation at the time that a wetlands jurisdictional determination (JD) was not a “final agency action” entitled to an administrative hearing because no permit had been issued. The Supreme Court, in a rare unanimous decision, especially when it comes to wetlands, held to the contrary. The JD had all the hallmarks of “finality” under the Administrative Procedures Act (APA), and therefore the Sacketts could challenge the JD.

Actions & Information Regarding the Clean Water Rule


Lawsuits filed in response to publication of Clean Water Rule


Useful Publications Regarding Wetlands & Jurisdictional Issue

Geographically Isolated Wetlands of the United States