Aerial view of a wetland with water and trees
WOTUS Update: EPA Removes Federal Protections for Many Wetlands

On August 29, 2023, the Environmental Protection Agency (EPA) and the United States Army Corps of Engineers (USACE) announced a final conforming rule to amend the final “Revised Definition of the ‘Waters of the United States’” rule, originally published in January 2023. The latest Waters of the United States (WOTUS) definition accounts for the May 2023 Supreme Court of the United States (SCOTUS) decision regarding the Sackett v EPA case.

Specifically, the new WOTUS definition removes the “significant nexus test” as it relates to identifying tributaries and other waters as federally protected. With the new WOTUS definition effective upon publication to the Federal Register, protections for many waterways and wetlands throughout the U.S. will soon fall under state jurisdiction.

WOTUS history: How we got here

1972-2005: WOTUS’s imprecise definition

Congress passed the Clean Water Act (CWA) in 1972, thereby establishing federal jurisdiction and regulatory authority over WOTUS. Congress did not precisely define the phrase WOTUS, however, and instead left that responsibility to EPA and USACE. Lacking a precise statutory definition of WOTUS, the agencies have struggled to adopt straightforward regulations for implementing the CWA.

2006-2014: Split SCOTUS WOTUS decision & regulatory uncertainty

Two Supreme Court of the United States (SCOTUS) decisions in the 2000s introduced further regulatory uncertainty. In 2006, Rapanos v. United States resulted in a split decision where Justice Antonin Scalia argued the CWA only applied to waterbodies “with a continuous surface connection” to navigable waters, whereas Justice Anthony Kennedy argued the CWA applied to any waterbodies that “affect the chemical, physical, and biological integrity of other covered waters” as evidenced by a “significant nexus” test.

In the wake of Rapanos, the agencies issued non-binding guidance in 2008 to implement Kennedy’s “significant nexus” test. However, the guidance failed to resolve many questions concerning the scope of federal jurisdiction and prompted arduous case-by-case analyses of whether the CWA applied to certain waterbodies.

2015: The Clean Water Rule divides the country

Amid persistent uncertainty in the post-Rapanos landscape, the agencies issued the Clean Water Rule in 2015 to circumscribe federal jurisdiction under the CWA. Among other changes, the 2015 rule specified which kinds of waterbodies would automatically receive protection under the CWA, exempted certain kinds of waterbodies from regulation, and identified which waterbodies still required case-by-case analyses. However, litigation and court orders delayed and constrained the implementation of the 2015 rule. When it eventually took effect in 2018, the Clean Water Rule applied in just 22 states, leaving other states bound to earlier versions of the regulations or awaiting direction from the courts. Despite its attempt at clarification, the 2015 rule ultimately created a confusing geographic mosaic of CWA jurisdiction.

2017 – May 2023: Revised WOTUS definition & landmark SCOTUS case at odds

It was against this backdrop that Executive Order 13778 was issued in 2017, which directed the agencies to repeal and replace the Clean Water Rule of 2015. The agencies completed their repeal of the Clean Water Rule in December 2019 and replaced it with the April 2020 Navigable Waters Protection Rule (NWPR), which narrowed the scope of federal jurisdiction under the CWA. In August 2021, the 2020 NWPR was vacated and remanded in response to EPA and USACE’s receipt of the U.S. District Court for the District of Arizona’s order in the case of Pascua Yaqui Tribe v. U.S. EPA. On December 30, 2022, the final “Revised Definition of ‘Waters of the United States’” rule was announced and the new rule was published in the Federal Register in January 2023. The rule took effect in March 2023, thereby redefining WOTUS and expanding the scope of federal jurisdiction under the Clean Water Act (CWA).

On May 25, 2023, the Supreme Court of the United States (SCOTUS) issued its decision regarding the Sackett v. EPA case, which centered on whether wetlands without a continuous surface water connection to regulated waters may themselves be regulated as WOTUS.

The Sackett v EPA case, between a private landowner and EPA, was submitted after Sackett, a private landowner in Idaho, attempted to alter their property. EPA notified Sackett that the property contained multiple wetlands and that altering the wetlands violated the CWA—to the tune of up to $40,000 per day. EPA claimed the wetlands as WOTUS “…because they were near a ditch that fed into a creek, which fed into Priest Lake, a navigable, intrastate lake.” Without a clear surface water connection to the aforementioned ditch or to another WOTUS, the Sacketts challenged the EPA’s jurisdictional claim.

In its May 2023 decision, SCOTUS unanimously favored Sackett in a 9-0 vote while adding clarity on what could be considered “adjacent” wetlands and thereby WOTUS. The decision stipulated that wetlands covered by the CWA must have a continuous surface connection to WOTUS “making it difficult to determine where the ‘water’ ends and the ‘wetland’ begins.” SCOTUS’s decision restricted EPA jurisdiction over isolated wetlands throughout the U.S. and identified the need for additional clarity in the WOTUS definition.

Present-day: Amended WOTUS definition conforms to SCOTUS decision

To align with SCOTUS’s determination that wetlands must have a continuous surface water connection to regulated waters to be considered WOTUS, EPA issued a final rule to amend the January 2023 definition in August 2023, rendering the concept of a “significant nexus test” moot. The amended WOTUS definition reads as follows:

  1. Waters of the United States means:

(I)   Waters which are:

(i) Currently used, or were used in the past, or may be susceptible to use in interstate or foreign commerce, including all waters which are subject to the ebb and flow of the tide;

(ii)   The territorial seas; or

(iii) Interstate waters;

(2) Impoundments of waters otherwise defined as WOTUS under this definition, other than impoundments of waters identified under paragraph (a)(5) of this section;

(3) Tributaries of waters identified in paragraph (a)(I) or (2) of this section that are relatively permanent, standing, or continuously flowing bodies of water;

(4) Wetlands adjacent to the following waters;

(i) Waters identified in paragraph (a)(I) of this section; or

(ii) Relatively permanent, standing or continuously flowing bodies of water identified in paragraph (a)(2) or (a)(3) of this section and with a continuous surface connection to those waters;

(5) intrastate lakes and ponds not identified in paragraphs (a)(I) through (4) of this section that are relatively permanent, standing or continuously flowing bodies of water with a continuous surface connection to the waters identified in paragraph (a)(I) or (a)(3) of this section.

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Margaret Caligaris headshot
Margaret Caligaris
Environmental Compliance & Permitting Specialist, San Luis Obispo, CA

Margaret is an environmental compliance and permitting specialist with over 4 years of experience in natural resource planning and permitting. She specializes in waters regulation, permitting, and stormwater compliance.

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