EPA Unveils New Definition of “Waters of the United States”

Author: Monica P. Schroeck|February 4, 2022

On December 7, 2021, the U.S. Environmental Protection Agency and the Department of the Army announced a proposed rule to revise the definition of “waters of the United States.” 
EPA Unveils New Definition of “Waters of the United States”

EPA Unveils New Definition of “Waters of the United States”

On December 7, 2021, the U.S. Environmental Protection Agency and the Department of the Army announced a proposed rule to revise the definition of “waters of the United States.” 

On December 7, 2021, the U.S. Environmental Protection Agency and the Department of the Army announced a proposed rule to revise the definition of “waters of the United States.”  The agencies are proposing to reinstate the pre-2015 definition, with updates to reflect consideration of Supreme Court decisions.  These Supreme Court decisions have not provided clarity on this issue and therefore much litigation has ensued regarding this term.

WOTUS Rule in Flux

Under the Clean Water Act (CWA), a permit must be obtained prior to the discharge of any pollutants into “navigable waters.” The CWA defines the term “navigable waters” as “waters of the United States, including the territorial seas.”  As described in greater detail in prior articles, the WOTUS Rule has been the subject of protracted litigation over the past several years. 

In 2015, the Obama Administration promulgated the “Clean Water Rule: Definition of ‘Waters of the United States,’” which broadly defined the scope of jurisdictional waters as whether a water or wetland possesses a “significant nexus” to waters that are or were navigable. The 2015 WOTUS Rule prompted significant litigation, which prevented it from being implemented in more than half of the country. Upon taking office, President Donald Trump made it a priority to repeal the Obama-era rule and create a more restrictive WOTUS definition. The EPA and Army subsequently rescinded the 2015 rule and proposed a new definition of WOTUS. The Trump Administration’s Navigable Waters Protection Rule (NWPR ) also prompted legal challenges. 

Following a federal district court decision vacating the NWPR on August 30, 2021, the agencies halted implementation of the NWPR and began interpreting “waters of the United States” consistent with the pre-2015 regulatory regime. According to the EPA, its current rule proposal is intended to bring greater legal certainty by largely returning to the familiar pre-2015 definition.

Proposed WOTUS Rule

On June 9, 2021, EPA and the Department of the Army announced their intent to revise the definition of WOTUS. Upon review of the NWPR, the agencies determined that it did not appropriately consider the water quality impacts of its approach to defining “waters of the United States,” in contravention of Congress's objective in the Clean Water Act “to restore and maintain the chemical, physical, and biological integrity of the Nation's waters,” and that the rule's reduction in the scope of protected waters could have a potentially extensive and adverse impact on the nation's waters. 

The agencies’ Proposed Rule establishes a revised WOTUS definition that would interpret “waters of the United States” to mean the waters defined by the longstanding 1986 regulations, with amendments to certain parts of those rules to reflect the agencies' interpretation of the statutory limits on the scope of the “waters of the United States” and informed by Supreme Court case law. Specifically, the agencies interpret the term “waters of the United States” to include: 

  • Traditional navigable waters, interstate waters, and the territorial seas, and their adjacent wetlands; 
  • Most impoundments of “waters of the United States”; 
  • Tributaries to traditional navigable waters, interstate waters, the territorial seas, and impoundments that meet either the relatively permanent standard or the significant nexus standard; 
  • Wetlands adjacent to impoundments and tributaries, that meet either the relatively permanent standard or the significant nexus standard; and 
  • “Other waters” that meet either the relatively permanent standard or the significant nexus standard. 

As explained in the Proposed Rule, the “relatively permanent standard” means waters that are relatively permanent, standing or continuously flowing and waters with a continuous surface connection to such waters. Meanwhile, the “significant nexus standard” means waters that either alone or in combination with similarly situated waters in the region, significantly affect the chemical, physical, or biological integrity of traditional navigable waters, interstate waters, or the territorial seas (the “foundational waters”). 

What’s Next?

The public comment period will close on February 7, 2022. According to the Rule Proposal, the agencies will consider all public comments on the proposed rule including changes that improve clarity, implementation and long-term durability of the definition. The agencies will also consider changes through a second rulemaking that they anticipate proposing in the future, which would build upon the foundation of this proposed rule.

The proposed WOTUS Rule while trying to provide clarity to the definition of navigable waters, still falls short in providing a roadmap to the regulated community.  As such, litigation on what WOTUS means will likely continue.  Members of the regulated community should, therefore, stay informed regarding WOTUS Rule developments and participate in the notice and comment process.

If you have questions, please contact us

If you have any questions or if you would like to discuss the matter further, please contact me, Monica Schroeck, or the Scarinci Hollenbeck attorney with whom you work, at 201-896-4100.


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AboutMonica P. Schroeck

Monica P. Schroeck has joined Scarinci Hollenbeck as Counsel with the firm’s environmental law practice team. Ms. Schroeck has extensive experience handling various environmental and land use issues, corporate transactions, as well as various environmental litigation matters on behalf of public and private entities.Full Biography

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EPA Unveils New Definition of “Waters of the United States”

EPA Unveils New Definition of “Waters of the United States”
Author: Monica P. Schroeck

On December 7, 2021, the U.S. Environmental Protection Agency and the Department of the Army announced a proposed rule to revise the definition of “waters of the United States.”  The agencies are proposing to reinstate the pre-2015 definition, with updates to reflect consideration of Supreme Court decisions.  These Supreme Court decisions have not provided clarity on this issue and therefore much litigation has ensued regarding this term.

WOTUS Rule in Flux

Under the Clean Water Act (CWA), a permit must be obtained prior to the discharge of any pollutants into “navigable waters.” The CWA defines the term “navigable waters” as “waters of the United States, including the territorial seas.”  As described in greater detail in prior articles, the WOTUS Rule has been the subject of protracted litigation over the past several years. 

In 2015, the Obama Administration promulgated the “Clean Water Rule: Definition of ‘Waters of the United States,’” which broadly defined the scope of jurisdictional waters as whether a water or wetland possesses a “significant nexus” to waters that are or were navigable. The 2015 WOTUS Rule prompted significant litigation, which prevented it from being implemented in more than half of the country. Upon taking office, President Donald Trump made it a priority to repeal the Obama-era rule and create a more restrictive WOTUS definition. The EPA and Army subsequently rescinded the 2015 rule and proposed a new definition of WOTUS. The Trump Administration’s Navigable Waters Protection Rule (NWPR ) also prompted legal challenges. 

Following a federal district court decision vacating the NWPR on August 30, 2021, the agencies halted implementation of the NWPR and began interpreting “waters of the United States” consistent with the pre-2015 regulatory regime. According to the EPA, its current rule proposal is intended to bring greater legal certainty by largely returning to the familiar pre-2015 definition.

Proposed WOTUS Rule

On June 9, 2021, EPA and the Department of the Army announced their intent to revise the definition of WOTUS. Upon review of the NWPR, the agencies determined that it did not appropriately consider the water quality impacts of its approach to defining “waters of the United States,” in contravention of Congress's objective in the Clean Water Act “to restore and maintain the chemical, physical, and biological integrity of the Nation's waters,” and that the rule's reduction in the scope of protected waters could have a potentially extensive and adverse impact on the nation's waters. 

The agencies’ Proposed Rule establishes a revised WOTUS definition that would interpret “waters of the United States” to mean the waters defined by the longstanding 1986 regulations, with amendments to certain parts of those rules to reflect the agencies' interpretation of the statutory limits on the scope of the “waters of the United States” and informed by Supreme Court case law. Specifically, the agencies interpret the term “waters of the United States” to include: 

  • Traditional navigable waters, interstate waters, and the territorial seas, and their adjacent wetlands; 
  • Most impoundments of “waters of the United States”; 
  • Tributaries to traditional navigable waters, interstate waters, the territorial seas, and impoundments that meet either the relatively permanent standard or the significant nexus standard; 
  • Wetlands adjacent to impoundments and tributaries, that meet either the relatively permanent standard or the significant nexus standard; and 
  • “Other waters” that meet either the relatively permanent standard or the significant nexus standard. 

As explained in the Proposed Rule, the “relatively permanent standard” means waters that are relatively permanent, standing or continuously flowing and waters with a continuous surface connection to such waters. Meanwhile, the “significant nexus standard” means waters that either alone or in combination with similarly situated waters in the region, significantly affect the chemical, physical, or biological integrity of traditional navigable waters, interstate waters, or the territorial seas (the “foundational waters”). 

What’s Next?

The public comment period will close on February 7, 2022. According to the Rule Proposal, the agencies will consider all public comments on the proposed rule including changes that improve clarity, implementation and long-term durability of the definition. The agencies will also consider changes through a second rulemaking that they anticipate proposing in the future, which would build upon the foundation of this proposed rule.

The proposed WOTUS Rule while trying to provide clarity to the definition of navigable waters, still falls short in providing a roadmap to the regulated community.  As such, litigation on what WOTUS means will likely continue.  Members of the regulated community should, therefore, stay informed regarding WOTUS Rule developments and participate in the notice and comment process.

If you have questions, please contact us

If you have any questions or if you would like to discuss the matter further, please contact me, Monica Schroeck, or the Scarinci Hollenbeck attorney with whom you work, at 201-896-4100.