Bryan Cave Combines with Berwin Leighton Paisner to Form Bryan Cave Leighton Paisner LLP Learn More

EPA and the U.S. Army Corps of Engineers Propose Yet Another Definition of “Waters of the United States” (“WOTUS”) – What to Expect in 2019

January 4, 2019

On December 11, 2018, the U.S. Environmental Protection Agency (“EPA”) and U.S. Army Corps of Engineers (the “Corps”) proposed new regulations that would sharply curtail the Corps’ permitting authority under the Clean Water Act (“CWA”) (the “New WOTUS Rule”).  The Agencies propose to do so in two-steps.  Step 1 would rescind a WOTUS rule promulgated by the agencies during the Obama administration (the “2015 WOTUS Rule”), whose expansive interpretation of the Corps’ permitting jurisdiction has been the subject of litigation throughout the country.  Step 2 would adopt a new definitional rule that would significantly limit the areas that are subject to permitting requirements under the CWA.

No issue of statutory interpretation in environmental law has generated more controversy, or been in dispute longer, than the CWA’s definition of “navigable waters.”  CWA Section 502(7) defines the term as “waters of the United States, including the territorial seas.”  This definition is fundamental to the scope of federal regulation under the statute, because it sets the jurisdictional boundaries of the permitting programs and numerous other legal requirements that the CWA imposes.  Specifically, under CWA Section 301(a), the discharge of a pollutant (including dredged and fill materials) into “navigable waters” is prohibited except in compliance with a permit issued under the CWA.  Thus, the federal government’s permission is only required when a discharge is into CWA “navigable waters.”1

Among the permits whose jurisdictional scope is set by the CWA’s “navigable waters” definition are CWA Section 404 permits issued by the Corps for dredging and filling activities.  Under Section 320.4(a) of the Corps regulations, the Corps has broad discretion in deciding whether an application for a Section 404 permit should be granted because the regulation allows the Corps to balance environmental, economic, safety and other factors to determine whether the proposed permitted activity is in the public interest.  In addition, the Corps must comply with the environmental review requirements of the National Environmental Policy Act before granting a Section 404 permit.  Thus, the Section 404 permit process can be time consuming, costly and uncertain.  The controversy over defining “waters of the United States” has centered on the whether the Corps’ authority under Section 404 extends to areas that do not fit neatly into the traditional meaning of “navigable waters.”  

As the rulemaking for the New WOTUS Rule proceeds in 2019, the best way to understand the issues surrounding the proposed regulations is to consider the most recent Supreme Court precedent on the jurisdictional scope of the CWA.

In Rapanos v. United States, 547 U.S 715 (2006), the Supreme Court reviewed a Sixth Circuit decision upholding the Corps’ decision to require a Section 404 permit for dredge and fill activities in wetlands adjacent to man-made ditches that ultimately emptied into traditional navigable waters.  The Corps made its determination in accordance with regulations and policies that required permits for activities not only in traditional navigable waters, but also in many other categories of waters, tributaries of such waters (which could be natural or man-made, and continuously flowing or intermittent or ephemeral) and wetlands “adjacent” to such waters and tributaries.  The term “adjacent” was interpreted broadly to include wetlands that are “bordering, contiguous [to], or neighboring waters of the United States” – even where separated from such waters by man-made features like berms or dikes.

In Rapanos, the Sixth Circuit upheld the Corps’ actions, citing a “significant nexus” consisting of a “hydrologic connection” between the wetlands at issue and traditional navigable waters.  Five members of the Court agreed that the standard applied by the Sixth Circuit was the wrong one, and remanded the cases for further proceedings.  However, the five member majority could not agree on why the Sixth Circuit standard was incorrect; instead, the Court issued two opinions setting forth different reasons for the remand, reflecting diverging views on the reach of the Corps’ authority under the CWA.  It is worth discussing those two opinions because Justice Kennedy’s is the foundation for the 2015 WOTUS Rule and the other, Justice Scalia’s, is the template for step 2 of the New WOTUS Rule.

According to Justice Scalia, writing for a plurality of four justices, the Corps’ interpretation of its regulations “stretched the term ‘waters of the United States’ beyond parody” by requiring permits for activities in “storm drains, roadside ditches, ripples of sand in the desert that may contain water once a year, and lands that are covered by floodwaters once every 100 years.”  He acknowledged that the Court had long interpreted the phrase “navigable waters of the United States” in predecessor statutes to the CWA as including waters that are navigable in fact or readily capable of being made so.  He also cited with favor Supreme Court precedent upholding Corps jurisdiction over wetlands adjacent to traditional navigable waters where a “significant nexus” was found to exist – but only under circumstances where the area was “characterized by saturated soil conditions and wetland vegetation [that] extended … to . . . a navigable waterway.” He rejected the proposition that a wetland constitutes “waters of the United States” whenever there is a nexus consisting of a “hydrologic connection” between the wetland area and the navigable waters.  Emphasizing that a distinction must be drawn between “water of the United States” and “waters of the United States,” he concluded that only “relatively permanent, standing or flowing bodies of water” (i.e., “waters”) and adjacent areas that share “a continuous surface connection” with such waters may be included within the latter phrase. 

Justice Kennedy, writing only for himself, concurred in the judgment vacating the Sixth Circuit decision.  His opinion sought to bridge the divide between Justice Scalia’s narrow interpretation of “waters of the United States” and the broader interpretation of the four dissenters who would have upheld the Sixth Circuit decision.  Justice Kennedy concluded that a wetland falls within the meaning of “waters of the United States” if it possesses a “significant nexus” to traditionally navigable waters, but that the Sixth Circuit erred in failing to consider all of the factors necessary to determine whether the lands at issue had such a nexus.  Drawing upon the purposes of the CWA, the unique characteristics of wetlands, and their potential importance to the aquatic environment of traditional navigable waters, he opined that a wetlands could be considered “waters of the United States” where “either alone or in combination with similarly situated lands in the region, [the wetlands] significantly affect the chemical, physical, and biological integrity of other covered waters more readily understood as ‘navigable.’”

The issue before the Court in Rapanos was the validity of the Corps’ interpretation of its regulations to require permits for the activities at issue, not the regulations themselves.  Accordingly, those regulations, which had last been amended in 1986, remained in effect subsequent to the Court’s decision.  However, the dueling opinions in Rapanos cast a shadow over the Corps’ 404 permit decision-making and set the stage for a series of regulatory activities attempting to “clarify” the jurisdictional scope of the CWA, a quest that is now continuing into 2019 with the proposed New WOTUS Rule.

On June 29, 2015, EPA and the Corps adopted the 2015 WOTUS Rule built around Justice Kennedy’s analysis in Rapanos.  As its preamble makes clear, “the final rule interprets the CWA to cover those waters that require protection in order to restore and maintain the chemical, physical or biological integrity of traditional navigable waters.”  The agencies defined the term “significant nexus” to reflect this expansive interpretation, and with that yardstick, identified eight categories of waters and wetlands that constitute “waters of the United States.”

A few examples illustrate the breadth of the 2015 WOTUS Rule’s jurisdictional reach.  Covered “tributaries” include waters (whether natural or man-made) that contribute flow, either directly or indirectly, to a traditional water.  Their flow can be continual, perennial, intermittent or ephemeral (i.e., flowing only when it rains) – and they even can be dry if they have indicators of the prior existence of a bed, bank or high water mark.  “Adjacent” and “neighboring” wetlands constituting jurisdictional waters include not only areas within 100 feet of a traditional water, but also those located within a 100 year floodplain of a traditional navigable water that are no more than 1,500 feet from the high water mark of the traditional water.  Indeed, areas as far as 4,000 feet from a traditional navigable water may be found to be jurisdictional waters if they are determined to have a “significant nexus” on a case-by-case basis.

As originally adopted, the 2015 WOTUS rule was to be applicable as of August 28, 2015.

The litigation that ensued from this “clarification,” along with subsequent administrative actions, have created a regulatory morass.  The U.S. District Court for North Dakota issued a preliminary injunction barring enforcement of the 2015 WOTUS Rule in 13 states,2 and the Court of Appeals for the Sixth Circuit stayed the rule nationwide – but that nationwide stay was thereafter vacated by the U.S. Supreme Court, which held that challenges to the 2015 WOTUS Rule must be filed in the district courts.3  Meanwhile the agencies under the Trump administration adopted a final rule amending the effective date of the 2015 WOTUS Rule to February 6, 2020, essentially rendering it a nullity until that date.4  But more litigation followed, and the U.S. District Court for South Carolina has issued an order enjoining the new effective date in several states.5  While appeals to that order are pending, the 2015 WOTUS Rule remains in effect in 22 states, and the agencies are making case-by-case determinations in the others.  The quest for regulatory clarity remains elusive.6

On February 28, 2017, President Trump issue an Executive Order entitled “Restoring the Rule of Law, Federalism, and Economic Growth by Reviewing the ‘Waters of the United States’ Rule.”7  That order directs the agencies to “consider interpreting the term ‘navigable waters’ … in a manner consistent with the opinion of Justice Antonin Scalia in Rapanos.”

The New WOTUS Rule was proposed in accordance with that directive.  In Step 1, the agencies have proposed to rescind the 2015 WOTUS Rule, and revert to the regulatory regime that had existed under the 1986 regulations, as interpreted by agency guidance and Supreme Court precedent.  Among the reasons put forward for this proposal is that the agencies have more than 30 years of experience in making jurisdictional determinations under the 1986 regulations, and are well versed in the judicial decisions – including Rapanos and other Supreme Court precedent – that have considered those regulations.  In Step 2, the agencies have proposed to adopt a new definitional rule consistent with Justice Scalia’s plurality opinion in Rapanos.  Among other things, that proposed rule would limit “adjacent wetlands” subject to CWA jurisdiction to those that “abut or have a direct hydrologic surface connection” to a traditional navigable water “in a typical year.”  The definition of a “tributary” is limited to a “river, stream, or similar naturally occurring surface water channel that contributes perennial or intermittent flow” to a traditional water.

The proposed rule has not yet been published in the Federal Register.  Comments on step 2 of the proposed New WOTUS Rule will be due within 60 days of publication.8


1. The potential applicability of state and local laws to such discharges is beyond the scope of this alert.

2.States of North Dakota, et al. v. EPA, 127 F. Supp. 3d 1047 (D.N.D. 2015).

3. National Assoc. of Manufacturers v. Department of Defense, 138 S. Ct. 617 (2018).

4. 83 Fed. Reg. 5200 (Feb. 6, 2018).

5. South Carolina Coastal Conservation League v. Pruitt, 318 F. Supp. 3d 959 (D.S.C. 2018).

6. The Agencies have provided a rule status and litigation update page.  See   https://www.epa.gov/wotus-rule/definition-waters-united-states-rule-status-and-litigation-update.

7. 82 Fed. Reg. 12,497 (March 3, 2017).

8. The comment period on Step 1 (repeal of the 2015 WOTUS Rule) closed on August 13, 2018.

Related Practices