Waters of the U.S.

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Contacts: Thomas Ward
(202) 266-8230

Adam Pugh
(202) 266-8662

The Clean Water Act (CWA) makes it unlawful for a person to add pollutants or dredge or fill material into a “water of the United States” (WOTUS) without a permit.

Since 1972, determining which water bodies are waters of the United States has been the subject of federal agency regulations, guidance and numerous cases both at the U.S. Supreme Court and at the lower federal courts. The U.S. Environmental Protection Agency (EPA) and the U.S. Army Corps of Engineers (Corps) (referred to as the Agencies) are charged with regulatory authority to define WOTUS under the CWA.

President Biden’s Revised Definition of WOTUS

The “Revised Definition of ‘Waters of the United States’ Rule” was published in the Federal Register on Jan. 18, 2023, and will go into effect March 20, 2023. The rule officially repeals the Navigable Waters Protection Rule (NWPR), implemented by the Trump administration, and puts into place a new definition of WOTUS.

President Biden’s revised definition of the waters of the United States dramatically expands the scope of the regulatory definition as compared to the NWPR by no longer excluding all ephemeral features from federal jurisdiction and instead requiring the Corps to perform “significant nexus” analyses upon otherwise isolated or ephemeral features to determine their jurisdictional status under the CWA.

A major flaw of this final rule is its heavy reliance upon the significant nexus test to determine the jurisdictional status of three out of the five jurisdictional categories (e.g., tributaries, adjacent wetlands, and interstate lakes, ponds or wetlands). The Agencies decision to finalize this rule is especially shortsighted, given that the Supreme Court’s upcoming ruling under Sackett v. EPA focuses on the legality of using the significant nexus test to assert federal jurisdiction under the CWA.

The revised definition of WOTUS lacks definitions for several key terms. The final rule also fails to include prior WOTUS categorical exclusions for features such as stormwater management devices and groundwater that were included in previous WOTUS definitions. Although the rule’s preamble attempts to provide some clarifying examples, it does not include these critical definitions nor exclusions in the regulatory text. Keywords that need clear definitions in the regulatory text include tributary, relatively permanent, material influence and artificial ponds, among others.

Jurisdictional Waters

The rule outlines these three water types are in federal jurisdiction:

  1. Traditional navigable waterways (TNWs) that impact interstate or foreign commerce
  2. Interstate waters, including interstate wetlands
  3. Territorial seas

In addition to the three foundational waters, the Agencies are including:

  1. Impoundments of foundational waters and impoundments that meet either the relatively permanent standard or the significant nexus standard
  2. Tributaries of foundational waters that meet either the relatively permanent standard or the significant nexus standard
  3. Adjacent wetlands to foundational waters, tributaries and impoundments that meet either the relatively permanent standard or the significant nexus standard
  4. Intrastate waters, such as lakes and ponds, streams or wetlands that meet either the relatively permanent standard or the significant nexus standard

The final rule lacks a clear definition of relatively permanent. The regulatory text does not define nor quantify what constitutes relatively permanent flow. The preamble merely says relatively permanent includes features that have flowing or standing water year-round or continuously during certain times of the year.

The final rule defines significantly affect as “a material influence on the chemical, physical or biological integrity of a WOTUS.” The final rule does not define nor shed much light on what constitutes “material influence.”

Through the significant nexus test, federal regulators will determine the jurisdictional status of a water based on its functions and factors. Federal agency staff will be considering the following:

  1. Functions to be assessed:
    1. Contribution to flow
    2. Trapping, transformation, filtering and transport of materials, including nutrients, sediment and other pollutants
    3. Retention and attenuation of floodwaters and runoff
    4. Modulation of temperature in waters
    5. Provision of habitat and food resources for aquatic species located in waters
  2. Factors to be considered:
    1. The distance from a WOTUS
    2. Hydrologic features, such as the frequency, duration, magnitude, timing and rate of hydrologic connections, including shallow subsurface flow
    3. The size, density or number of waters that have been determined to be similarly situated
    4. Landscape position and geomorphology
    5. Climatology variables such as temperature, rainfall and snowpack

Excluded Waters

The final rule explicitly excludes the following water bodies:

  1. Waste treatment systems (WTS), including ponds or lagoons, designed to meet the requirements of the Clean Water Act.
    1. The preamble clarifies that WTS constructed prior to the enactment of the CWA can still be excluded and that WTS are not limited to humanmade bodies of water, consistent with longstanding practice.
  2. Prior converted croplands (PCC) designated by the U.S. Department of Agriculture (USDA).
    1. The exclusion would cease upon a change of use, which means that the area is no longer available for the production of agricultural commodities. For CWA purposes, the final authority regarding CWA jurisdiction remains with EPA.
    2. The preamble implies, but does not clearly state, that lands remain excluded as PCC even if they change to a non-agricultural use so long as wetland characteristics do not return.
  3. Ditches, including roadside ditches, excavated wholly in and draining only dry land and that do not carry a relatively permanent flow of water
    1. Excluded ditches would not become jurisdictional solely by virtue of connecting to a downstream WOTUS or because wetland characteristics develop within the confines of the ditch.
  4. Artificially irrigated areas that revert to dry land if irrigation ceased
  5. Artificial lakes or ponds created by excavating or diking dry land to collect and retain water, and are used for such purposes as stock watering, irrigation, settling basins or rice growing
    1. The preamble says this exclusion applies only to lakes and ponds that satisfy the terms of the exclusion. It is unclear if other types of ponds, such as log-cleaning ponds, would not qualify.
  6. Artificial reflecting or swimming pools or other small ornamental bodies of water created by excavating or diking dry land to retain water for primarily aesthetic reasons
  7. Waterfilled depressions created in dry land incidental to construction activities and pits excavated in dry land to obtain fill, sand or gravel unless and until the construction or excavation operation is abandoned and the resulting body of water meets the definition of WOTUS
  8. Swales and erosional features, gullies, small washes, characterized by low volume, infrequent or short duration flow

Why It Matters

When home builders need to add fill material into a water of the United States, they must first get a permit from the Corps. Obtaining permits is costly and time-consuming. For example, one study found that it costs, on average, $270,000 and takes 788 days to obtain an individual CWA fill permit.

As the Agencies expand the definition of WOTUS, builders will need to obtain additional or more onerous permits, spending more time and resources to avoid wet features.

Ironically, this comes at a time when the Biden administration has declared an affordable housing crisis. The administration has a laudable goal to increase the production of affordable housing units while at the same time reducing regulatory barriers to new affordable housing. One of the ways the administration aims to achieve this is by tying federal funding incentives to states and local governments to reduce land use and zoning barriers to new affordable housing projects.

The White House acknowledges that one of the most significant issues constraining housing supply and production is the lack of developable land — specifically, affordable building lots. Unfortunately, the administration fails to see how its own policies, and particularly environmental regulations such as the new WOTUS rule, create more barriers to affordable housing when the larger U.S. housing market already faces high mortgage rates, escalating costs for building materials, and an overall nationwide deficit of 1.5 million new single-family homes.

NAHB Resources on WOTUS

Agency Resources on WOTUS

For the latest WOTUS information, visit NAHBNow.

Tell Congress to Repeal Biden’s WOTUS Rule Call or write your member of Congress and ask them to vote yes on H.J. Res 27.
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