What Are ‘Waters of the United States’?

It Depends on Where You Work – And When You Ask.

By Ali Nelson

The Clean Water Act protects “waters of the United States” through a number of federal programs, including the Section 404 permit program regulating the discharge of dredged or fill material into “navigable waters.”

The definition of “navigable waters” is therefore crucial to determining whether a permit is required. Unfortunately, its meaning is far from settled, which can create significant compliance issues for any mine, processing facility or construction site conducting activities with the potential to disturb waters that fall under this definition.

History and Litigation

The Clean Water Act itself simply defines “navigable waters” as “the waters of the United States,” which offers little help. Regulations adopted in the 1980s defined “waters of the United States” to include waters that are navigable in fact; waters that are used in interstate commerce; and other waters the use, degradation or destruction of which would affect interstate commerce, including wetlands adjacent to such waters.

The regulatory definition has since been tested in several key U.S. Supreme Court decisions; for instance, in Rapanos v. United States, 547 U.S. 715 (2006), the Court held that the Clean Water Act’s jurisdiction extends to any water with a “significant nexus” to traditional navigable waters. In his concurring opinion in that case, Justice Kennedy stated that a “significant nexus” is present if the waters “significantly affect the chemical, physical, and biological integrity of other covered waters more readily understood as ‘navigable’.”

The U.S. Environmental Protection Agency (EPA) and the U.S. Army Corps of Engineers (USACE) have issued guidance as well. However, the regulations, case law and guidance didn’t remove the ambiguity surrounding when a water was subject to regulation, and a case-by-case jurisdictional determination was required for projects to proceed with any certainty.

In an attempt to provide that certainty, EPA and USACE adopted a final “Clean Water Rule” in 2015 defining “waters of the United States” to specifically include waters with a significant nexus to traditional navigable waters. That rule subjected certain categories of waters to jurisdiction, including tributaries with certain features (such as a bank and a high water mark), “adjacent waters” that are within a certain distance of jurisdictional waters, and certain “isolated waters” of ecological importance (such as prairie potholes).

But many thought the rule went too far; even before he assumed the role of EPA Administrator, Scott Pruitt voiced his opposition to the Clean Water Rule as “the greatest blow to private property rights the modern era has seen,” and President Trump referred to the rule as “one of the worst examples of federal regulation.”

A flurry of lawsuits were filed against the rule, and the U.S. Court of Appeals for the Sixth Circuit ruled in the cases consolidated before it that it (and not the district courts) had jurisdiction over the litigation, staying proceedings in the district courts. On appeal to the U.S. Supreme Court, that Court decided on Jan. 22, 2018, that the cases should be heard by the district courts instead, and the Sixth Circuit lifted its stay on Feb. 28, 2018.

Challenges to the Clean Water Rule were also proceeding in the executive branch at the same time. President Trump signed an executive order shortly after taking office ordering EPA and USACE to take rulemaking action to withdraw the Clean Water Rule, and EPA and USACE published a final “Suspension Rule” on Feb. 6, 2018, delaying the effective date of the Clean Water Rule for two years. EPA and USACE sent a new proposed definition to the White House for review on June 15, 2018, which will undoubtedly define “waters of the United States” more narrowly.

Recent Developments

With the stay lifted, lawsuits in district courts across the country resumed, and others were filed in opposition to the Suspension Rule. On Aug. 16, 2018, the U.S. District Court for the District of South Carolina entered an order enjoining the Suspension Rule on the grounds that it violated the procedural requirements of the Administrative Procedure Act, including the requirement to solicit public comment on the rule’s substance and merits. Specifically, the court held that:

The agencies refused to engage in a substantive reevaluation of the definition of the “waters of the United States” even though the effect of the Suspension Rule is that the definition of “waters of the United States” ceases to be the definition under the WOTUS rule and reverts to the definition under the 1980s regulation. The definition of “waters of the United States” is drastically different under these two regulations.

Although the agencies did solicit comments prior to adopting the final rule, that request was limited to “whether it [was] desirable and appropriate to add an applicability date” to the Clean Water Rule, and whether the two-year delay should be “shorter or longer.” The court found this to be inadequate, commenting that “An illusory opportunity to comment is no opportunity at all.”

As a result, the Clean Water Rule went back into effect in 26 states: California, Connecticut, Delaware, Hawaii, Illinois, Iowa, Louisiana, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, New Hampshire, New Jersey, New York, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, Tennessee, Texas, Vermont, Virginia, Washington. (Earlier injunctions in the remaining states stayed the applicability of the Clean Water Rule, so the South Carolina district court’s ruling does not impact the state of the law in those states.)

However, it’s likely that the Clean Water Rule will not remain in effect for long. On Sept. 12, 2018, the U.S. District Court for the Southern District of Texas entered an injunction blocking the Clean Water Rule from taking effect in Texas, Mississippi and Louisiana. The court’s order noted that “clarification regarding what is, and what is not, a navigable water under the Clean Water Act is long overdue” and, “until that question can ultimately be answered, a stay provides much needed governmental, administrative, and economic stability.”

The court further emphasized the significant resources that a state would need to allocate to determining how to interpret and implement the Clean Water Rule. However, it found that it was “inappropriate” to enjoin the Clean Water Rule’s application nationwide, noting that “the evidence before the Court is insufficient to establish whether implementation of the Rule presents an irreparable harm to those states not a party to this litigation.” Enjoining the Clean Water Rule’s application in other states will therefore require additional action by the courts.

What All of This Means

Staying on top of the status of the EPA and USACE rulemakings and keeping an eye out for new decisions by courts across the country will be crucial to staying in compliance with the wetlands permit program requirements. But even that won’t do away with all risks associated with mining or construction activities that have the potential to impacts waters that may potentially impact jurisdictional waters, given the uncertainty surrounding the status of the law.

To ensure compliance, companies may want to consider conservatively applying the Clean Water Rule definition (especially in those states where courts have reinstated the Clean Water Rule, but not only in those states); seeking a jurisdictional determination from EPA and USACE for specific waters so any discharges are with the agencies’ blessing; delaying new construction or expansion impacting potentially jurisdictional waters until the definition is clearer.

We’d like to think the confusion will only be temporary, given that the replacement rule proposed by EPA and USACE should be made public soon. However, given the significant litigation that has faced this rule since its inception, we expect to see similar challenges to the replacement rule as well. It may be some time before the issue is settled.


Ali Nelson is senior counsel at Husch Blackwell LLP. As a member of the firm’s Energy & Natural Resources team, she has experience advising companies in connection with mining and mineral extraction, regulated transmission projects, coal-fired power plants, and renewable and clean energy projects. [email protected], 303-749-7263.

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