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Science, Law & the Environment Emerging Topics in Environmental Law

First Reaction to EPA’s Just-Released Draft of the Definition of “Waters of the United States” Under the Clean Water Act

Posted in Clean Water Act, Emerging Policy, Rule Making, Water Quality

The EPA and Army Corps of Engineers released a preview of the long-awaited proposed rule updating the definition of “Waters of the United States” yesterday morning. The proposed rule will soon be published in the Federal Register, but the unofficial version of the rule is available now. My initial reaction is that this rule—while being couched in terms of providing “regulatory certainty”—may actually expand the scope of waters regulated under the Clean Water Act (CWA).

Not surprisingly, the EPA and Corps followed Justice Kennedy’s concurring opinion in Rapanos v. United States, that concluded that wetlands were “Waters of the United States” if those wetlands had a “significant nexus” to waters that are or were navigable, or could reasonably be made so. A “significant nexus” was defined by Justice Kennedy as wetlands that “either alone or in combination with similarly situated [wet]lands in the region, significantly affect the chemical, physical or biological integrity of other covered waters more readily understood as navigable.” This definition of significant nexus runs throughout the just-released proposed definition of “Waters of the United States,” and uses Kennedy’s language and concepts.

The core of the proposed definition of the “Waters of the United States” are waters that have been traditionally regulated under the CWA and the Rivers and Harbors Act pursuant to Congress’s Commerce Clause authority, i.e., navigable waters, including waters that have been navigable in the past or may be susceptible to use in interstate or foreign commerce; wetlands that are interstate in nature; territorial seas; and impoundments of these types of waters. I’ll refer to these waters as “traditional waters” through the rest of this post.

Layered on top of these traditional waters of the United States are tributaries, defined for the first time by the EPA and Corps in reference to physical characteristics (presence of a high water mark), and connectivity to traditional waters through contribution of flow to those waters. Before this proposed rule, the EPA and Corps evaluated tributaries on a case-by-case basis using the significant nexus test. Now, the EPA and Corps are—through rulemaking—making a determination that there is a significant nexus between these tributaries that meet the proposed definition and traditional waters. EPA and the Corps argue in the preamble to the rule that this determination will give greater certainty to the regulated community because it will eliminate an entire class of waters that otherwise would have to go through a case-by-case significant nexus determination.  But, the practical effect of this portion of the rule is that it will cement many tributaries as “Waters of the United States” and remove the case-by-case determination of a significant nexus that EPA and the Corps has been performing post-Rapanos. As a result, this categorical inclusion of tributaries arguably broadens the definition of “Waters of the United States.”

Continuing with the significant nexus theme, the EPA and Corps are modifying the current definition of “other waters” in the proposed rule. In the current definition, “other waters” are defined based on a test of whether the degradation or destruction of those waters could affect interstate or foreign commerce. The proposed rule imports Justice Kennedy’s significant nexus test in determining jurisdiction over “other waters,” and the EPA and Corps are proposing to make jurisdictional determinations over these waters on a case-by-case basis. How to define and treat these “other waters” under the CWA is one of the main parts of the rule where the EPA and Corps are seeking feedback.

Also included in the proposed rule are changes to the definition of “adjacent” waters, i.e., waters defined by the geographic relationship to traditional waters. The previous rule referenced adjacent wetlands only, and the new rule—in response to a judicial interpretation of the old rule—now includes in its scope both adjacent wetlands and other waterbodies. Functionally, this sweeps into CWA jurisdiction waters beyond adjacent wetlands such as the one analyzed in Rapanos. Once again, the significant nexus test is what the EPA and the Corps relies upon in bringing these other waterbodies within CWA jurisdiction. They do so by “clarifying” the issues of adjacency—i.e., when is a water or wetland considered to be a “Water of the United States” based on its geographic relationship to traditional waters, by applying the significant nexus test and through a series of definition changes. The proposed rule defines an “adjacent” water as one that is boardering, contiguous, or “neighboring” traditional waters, and then includes within the term “neighboring” waters located in “riparian” areas or “floodplains” adjacent to traditional waters. This nesting of definitions may have the practical effect of expanding the reach of CWA into floodplains or riparian areas that contain what otherwise may be relatively isolated waterbodies, and once again reflects the categorical inclusion of classes of waters based in a determination of significant nexus through this rulemaking. This is another example of how the proposed rule expands CWA jurisdiction.

Comments on the proposed rule will be due 90 days after the date of publication in the Federal Register. I’ll update this post once the proposed rule is published.