Revised Definition: Waters of the United States & Significant Nexus

adminAdvocacy, Codes, Featured, Land Development

Insight and opinions regarding the regulatory expansion of federal Clean Water Act jurisdiction based on “significant nexus” by Jim Coody, P.E.

The Environmental Protection Agency (EPA) and Corps of Engineers (the agencies) recently published new rulemaking in the Federal Register on January 18, 2023, and it goes into effect on March 20, 2023. The Biden Rule once again revises the definition of Waters of the United States (WOTUS) and codifies a new regulatory regime dubbed significant nexus.[1]

Since its inception in 1977, the federal wetlands regulatory program has never evolved to become a well-organized, stable, and predictable environmental regulatory organization. Wetlands rules have always been in a constant state of change and continue to expand with the establishment of significant nexus under the Biden Rule.

Significant nexus is an all-encompassing environmental/philosophical concept and legal paradigm. Significant nexus is comparable to the breadth and scope of the former Migratory Bird Rule that was struck down in 2001 by the U.S. Supreme Court with the SWANCC decision.[2]


The Biden Rule and former Migratory Bird Rule share a wide-ranging and expansive scope of federal regulatory authority. The Migratory Bird Rule stipulated that any so-called “waters” that a migratory bird could use as habitat, were considered Waters of the United States (WOTUS) and thus regulated under Section 404 of the Clean Water Act (CWA). Accordingly, isolated wetlands, isolated ponds, ephemeral streams, ditches, detention ponds, and other so-called “waters” throughout America were broadly regulated based on the Migratory Bird Rule for 15 years from 1986 to 2001.

Significant nexus will impose voluminous and complicated technical details related to navigable waters, wetlands, habitat, floodplains, ecology, climate change, and environmental justice; for the purpose of determining CWA jurisdiction on a case-by-case basis.

Significant nexus will radically change prior regulations, legal authorities, permitting, and enforcement procedures; and bring previously exempt development activities under direct control of the federal government.

The agencies have been promoting the concept of “significant nexus” for many years based on loose guidelines from the 2008 Rapanos Guidance memorandum.[3] Before the Biden Rule, significant nexus was not an official regulation and had no binding legal authority.

Around ten years ago the agencies informally applied significant nexus to support a CWA jurisdictional determination on the Sackett property in Idaho, and this sparked a long running lawsuit.

The Supreme Court is currently considering the legal status of significant nexus in the case of Sackett vs EPA.[4] The Court heard oral arguments in October 2022 and is expected to issue a ruling by summer 2023.
The Supreme Court could nullify and vacate significant nexus like it did to the Migratory Bird Rule, or it could limit the scope and applicability of significant nexus. The Court could mandate the agencies to go back and modify the Biden Rule or possibly abandon this rule altogether.

It is also possible the Supreme Court could affirm significant nexus in its present form and uphold the Biden Rule. Such an outcome would be a severe setback for landowners and the regulated community and would trigger litigation starting in federal district courts.

Opposition to the Biden Rule & Significant Nexus

There is widespread opposition to the Biden Rule from real estate development, agricultural, mining, industrial, and other organizations that represent the regulated public. The National Association of Homebuilders (NAHB) promptly issued a letter on Jan. 2, 2023 strongly condemning the new rule.[5]
The U.S. House of Representatives Committee on Transportation & Infrastructure opposes the Biden Rule and published a list of comments from numerous industries and trade groups.[6] The new congress may act to halt or delay implementation of the Biden Rule.

What Now?

As we await the Supreme Court’s Sackett vs EPA decision later this year, what should you do?
Landowners should be cautious about entering the wetlands permitting process given ongoing regulatory uncertainty surrounding the Biden Rule and how it could be implemented. The federal wetlands regulatory program may not be functionally stabilized until 2024 or later.

Landowners have the option of obtaining an independent expert analysis of CWA jurisdiction for their property based on current regulations, relevant court decisions, site-specific circumstances, and accurately document the regulatory status in a “Wetlands Report” preferably sealed by a professional engineer.

For certain projects which are designed to avoid impacts to jurisdictional wetlands and WOTUS, and are properly documented to verify regulatory compliance, landowners and developers have the legal right to exercise an “informed decision” to not-request an Approved Jurisdictional Determination (AJD) from the Corps of Engineers.

Landowners should maintain their land to restore good drainage, mow vegetation, and reduce the potential for regulatory encumbrances. Do not allow wetlands plants to propagate and spread because of neglected maintenance. Make sure that ditches and culverts are clean and clear of obstacles.

As information develops in 2023, stay tuned for periodic updates on the latest developments regarding wetlands and Waters of the United States (WOTUS).

About the Author:

Jim Coody is a Professional Engineer and President of Wetlands Professional Services. Mr. Coody has over 30 years of experience practicing in wetlands regulatory compliance and related environmental disciplines. Wetlands Professional Services’ clients include private owners of large and small tracts of land, real estate developers, brokers, utility and drainage districts, school districts, industrial sites, and large residential subdivision projects. Areas of specialization include analysis and documentation of wetlands, streams, ditches and ponds; endangered and threatened species, stormwater drainage, maintenance of raw land to re-establish good drainage, coordination with government agencies, and project management. Mr. Coody advocates for landowners property rights, while making use of equitable and balanced methodologies that comply with applicable law and regulations. Learn more at or contact Jim Coody at (713) 858-6463.


[1] Biden Rule pre-publication version 12-30-2022 –
[2] SWANCC decision / Migratory Bird Rule –
[3] Rapanos Guidance Memorandum 2008 –
[4] Sackett vs EPA
[5] NAHB letter responding to Biden Rule –
[6] U.S. House Committee on Transportation & Infrastructure –