Updated WOTUS definition following Sackett


Staff member
Apr 16, 2023
Yesterday, the Biden administration issued a final rule amending the definition of "waters of the U.S." (WOTUS). This is a big deal because Section 404 of the Clean Water Act (CWA) requires that a permit be obtained for any activity that results in a "discharge of dredged or fill material into waters of the U.S." However, what types of waterbodies qualify as a WOTUS has remained notoriously unclear since passage of the CWA 51 years ago.

Are all types of tributaries, ranging from large rivers to small headwater streams, considered WOTUS? What wetlands count as WOTUS - all of them, or just those that provide functions and services to downstream waters? If the latter, how do you even determine that? These are the questions that different administrations and courts have repeatedly grappled with over the years. In fact, different administrations have made a total of eight different regulatory changes to the WOTUS definition since enactment of the CWA in 1972. Since 2015 there have been more than a dozen regulatory or litigation actions changing which definition of WOTUS applies in one or more states.

By interpreting WOTUS consistent with the recent Supreme Court ruling in Sackett v. EPA, it appears that yesterday's final rule - dubbed the "conforming rule" - largely puts an end to the WOTUS rollercoaster ride. The new rule makes clear that regulated tributaries are limited to "relatively permanent, standing or continuously flowing bodies of water" (i.e., no small ephemeral streams). Wetlands are now only WOTUS if they have a continuous surface connection with a regulated tributary or downstream waterway, the upshot being that many wetlands that previously met the WOTUS definition are now excluded.

The new rule will go into effect once it's published in the Federal Register, which is expected to happen in the weeks ahead. The next chapter will be seeing how the rule is implemented in practice by different Corps District offices and how different administrations approach the rule. Will this rule endure, or will different administrations seek out new opportunities to narrow or broaden WOTUS based on their own policies and whatever legal wiggle room they have?
United States
Following up on this post, EPA officially published the Conforming Rule in the Federal Register as of September 8, making it effective. The Corps can now issue Approved Jurisdictional Determinations (AJDs) documenting non-jurisdictional status of non-relatively permanent waters (RPWs) and non-adjacent wetlands (i.e., those lacking a continuous surface connection to RPWs). As discussed in this Holland & Knight article, the new rule makes some notable omissions, in particular by not expanding the list of excluded waters to encompass non-adjacent wetlands and non-RPWs. Nevertheless, at least in the 27 states where the 2023 Rule isn't current enjoined, the Corps has proceeded with issuing AJDs documenting these waters as non-jurisdictional, though further guidance to inform these determinations is pending and will likely be based on district-level interpretations for the foreseeable future.

Holland & Knight summarize their assessment of the Conforming Rule as follows:

The WOTUS Rule appears to be as narrow of an application of the Sackett decision as the Biden Administration thought possible. While parroting back certain language of the Supreme Court, the WOTUS Rule fails to truly define what constitutes a "relatively permanent" waterbody or a "continuous" connection between a wetland and such a water. While it was expected that the Sackett decision would result in the exclusion of ephemeral waters that only possess water following a rainfall event, the WOTUS Rule attempts to dodge that limitation. The agencies also plan on issuing further guidance and hint that they can provide guidance through approved jurisdictional determinations. Further litigation from all sides seems inevitable.
The 2012 Supreme Court case, Sackett v. EPA, delved into concerns surrounding the definition of WOTUS and shed light on specific aspects of it. However, it's important to note that any revisions to the definition after this case would hinge upon subsequent developments in law and regulations, which can vary across different jurisdictions and evolve over time.