In a 50-year game of ping-pong, the Biden administration marked the end of 2022 by taking its turn revising the definition of “waters of the United States,” or “WOTUS” for short. This term determines where Clean Water Act (CWA) permits are required for wetland dredging and filling and pollutant discharges, as well as other CWA jurisdictional limits. On December 30, 2022, the Environmental Protection Agency and Army Corps of Engineers (together, the Agencies) released a pre-publication version of the “Revised Definition” WOTUS rule and additional guidance materials; but the regulation does not take effect until 60 days after its official publication (still pending).

The Biden administration’s new rule identifies five categories of WOTUS, starting with less controversial waterbodies, such as large, actually-navigable rivers and lakes known as “traditional navigable waters” (TNW). From there, the rule defines additional categories and subcategories of WOTUS by applying both standards offered in the plurality and concurring opinions of the Supreme Court’s 2006 Rapanos v. U.S. decision. As outlined below, this approach includes not only features meeting Justice Scalia’s test (“relatively permanent, standing or continuously flowing” waters and wetlands with continuous surface connections to such waterbodies) but also those swept in under Justice Kennedy’s “significant nexus” trigger (“significantly affect[ing] the chemical, physical, and biological integrity” of TNW):

Para.WOTUS Category Regulatory Triggers
(a)(1)Traditional navigable waters, territorial seas, and interstate waters, forming the core (and perhaps least controversial) category of jurisdictional waters
(a)(2)Impoundments of WOTUS identified in other categories, except (a)(5) local waters
(a)(3)Tributaries of TNW and other core (a)(1) waters and (a)(2) impoundments, limited to such streams, ponds, impoundments, and other tributary waterbodies:
(i)that are “relatively permanent, standing or continuously flowing” (as most followers of Justice Scalia would tolerate); or
(ii)that significantly affect the chemical, physical, or biological integrity of any core (a)(1) waterbody
(a)(4)Adjacent wetlands in locations meeting federal “wetland” criteria (hydrologic and vegetation) and:
(i)adjacent” (“bordering, contiguous, or neighboring”) to TNW or other core (a)(1) waters;
(ii)possessing a “continuous surface connection” to any (a)(2) impoundment or “relatively permanent” (a)(3)(i) tributary; or
(iii)significantly affecting the chemical, physical, or biological integrity of any core (a)(1) waterbody and “adjacent” to any (a)(2) impoundments or (a)(3) tributaries
(a)(5)Additionalintrastate lakes and ponds, streams, or wetlands” where such local waters are either:
(i)relatively permanent … with a continuous surface connection” to any core (a)(1) waterbody or any “relatively permanent” (a)(3)(i) tributary; or
(ii)significantly affecting the chemical, physical, or biological integrity of any core (a)(1) waterbody

The Biden administration describes its new WOTUS definition as putting back into place the regulatory scheme in effect before the Obama and Trump administrations took turns revising this term. But, by expressly including “significant nexus” triggers, the new rule more closely resembles the Obama administration’s broad 2015 Clean Water Rule than the Trump administration’s more narrow 2020 Navigable Waters Protection Rule (NWPR). The new rule goes further by adding new criteria for determining when a water feature trips this trigger because it has a “material influence on the chemical, physical, or biological integrity of [TNW, territorial seas, or interstate waters],” either “alone or in combination with similarly situated waters in the region.” The Biden administration claims that the rule’s new terms and updated exceptions for ditches, construction site depressions, wastewater treatment ponds/lagoons, prior converted croplands, artificial ponds/irrigation areas, and similar features are supported by its extensive public outreach to agricultural, tribal, state, and other stakeholders. Countering longstanding criticisms that “significant nexus” considerations unduly burden farming, infrastructure, and other projects with complex and expensive study requirements, the Agencies also point to past guidance and additional materials now available to facilitate predictable WOTUS determinations.

The Biden administration may be positioning its Agencies to make future “Rule 2” WOTUS definition changes if the U.S. Supreme Court invalidates or cuts back the “significant nexus” trigger in a pending appeal brought by the Sackett family against EPA. In that case, EPA issued an order and a jurisdictional determination that applied the significant nexus test to prohibit further filling and home construction activities on the Sackett’s “soggy” property located 300 feet from Priest Lake, a TNW in Idaho. The wetlands on their 0.63 acre lot drain into the lake beneath the ground surface but, thanks to intervening roads and residences, have no surface connection to Priest Lake or any other TNW. The lot’s wetlands are part of a larger wetland resource that has been found to impact Priest Lake. The Ninth Circuit’s 2021 decision in Sackett affirmed summary judgment in favor of EPA based on the “significant nexus” test, rejecting the Sackett’s argument that Justice Scalia’s plurality opinion should control. The present appeal to the Supreme Court has been briefed and argued; a decision is expected later this year.

The Biden administration has also lobbed its new WOTUS definition into the Court’s deliberations on the Sackett case. In a December 30, 2022 letter, the Office of the Solicitor General provided a link to the now “final rule” and pointed to the Agencies’ preamble comments describing which “adjacent wetlands” are regulated as WOTUS. EPA’s announcement issued on the same day seems to speak to both the Court and the public by describing the new rule as “durable” and “grounded in the authority provided by Congress [and reflecting] existing Supreme Court decisions, the latest science, and the agencies’ technical expertise.”

For now, the WOTUS ball is back in the hands of the Supreme Court. But, by forcing out its “durable” Phase 1 rule and reserving a place for potential Phase 2 rulemaking, the Biden administration is sending the Court and interested stakeholders a message that its Agencies are prepared to keep hitting back any narrow CWA interpretations sent their way in this game of WOTUS ping-pong, now entering into its sixth decade.

(*) For further discussion on the revised WOTUS rule and Sackett case, see the longer client alert. Attorney Melvin’s additional articles and presentations on water and wastewater topics appear in Environmental Law+ blog and other Robinson + Cole publications.