Issue Brief

Waters of the United States

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On January 23, 2020, the Environmental Protection Agency (EPA) and U.S. Army Corps of Engineers (Corps) issued a new rule redefining the scope of waters subject to federal jurisdiction under the Clean Water Act (CWA) titled, the “Navigable Waters Protection Rule.” The new 2020 rule replaces the 2015 redefini­tion effort that expanded the federal government’s jurisdiction over waters of the U.S. (WOTUS). The American Public Power Association (APPA) did not support the 2015 WOTUS rule because it dramatically expanded the definition of WOTUS, which could have subjected more utility projects and activi­ties to CWA jurisdiction. The 2015 rule became the subject of intense litigation at the federal district and circuit court levels and, as result, only went into effect in 25 states, while the pre-2015 definition remained in place in 25 states. In February 2017, President Trump signed an Executive Order (EO) direct­ing the agencies to redefine WOTUS in a more limited manner. EPA and the Corps implemented the EO in two steps: a repeal of the 2015 rule (effective December 23, 2019) and a revision of the definition of WOTUS. APPA supports the new defini­tion, which provides clarity and certainty while protecting the environment.



The CWA gave the federal government the authority to regulate pollution of navigable waters, known as “waters of the United States.” This seems straight forward, but given the interconnect­edness of surface waters—clearly navigable large rivers and lakes are fed by streams and other smaller bodies of water that are clearly not navigable—the line of the federal government’s ju­risdiction is a fuzzy and moving one. Years of legal battles came to a head in a 4-1-4 ruling by the U.S. Supreme Court in 2006 in Rapanos v. United States. Justice Anthony Kennedy joined the conservative wing of the court in ruling that the govern­ment could no longer broadly interpret its jurisdiction. In other words, the government needed to write a new set of rules for determining where it had jurisdiction. Justice Kennedy wrote a standalone opinion suggesting that the government limit its jurisdiction to waters that have a “significant nexus” with navigable waters. Instead of providing clarity, determining what constituted a significant nexus caused further confusion. EPA and the Corps attempted to define what constitutes a “signifi­cant nexus” for the purposes of defining WOTUS in 2015. The 2015 rule dramatically expanded the agencies’ federal author­ity, which could have triggered additional, costly CWA permit requirements for new utility projects or when maintenance was performed on existing infrastructure and facilities. For example, if ditches and associated features were jurisdictional, a util­ity could have been required to obtain a permit every time it constructed, repaired, or even maintained a right-of-way (e.g., through plant clearing or herbicide application). This would have been incredibly burdensome and costly. The 2020 final rule correctly excludes most ditches and associated features from CWA jurisdiction.


Administrative Action

In February 2017, President Trump signed Executive Order 13778, “Restoring the Rule of Law, Federalism, and Economic Growth by Reviewing the ‘Waters of the United States’ Rule,” directing EPA and the Corps to engage in a notice and com­ment rulemaking to propose a rule to rescind or revise the WO­TUS rule consistent with the CWA. The EO further directed the agencies to interpret the term navigable waters in a manner consistent with the opinion authored by Justice Antonin Scalia in the 2006 Rapanos case, who viewed federal jurisdiction as limited to where navigable waters are connected by a surface flow at least part of the year.

The agencies developed a process for implementing the EO in two steps:

Step 1 - Repeal

On October 22, 2019, EPA and the Corps published in the Federal Register a final rule to repeal the 2015 rule and recodify the regulation that was in place prior to issuance of the 2015 rule. The 2019 rule became effective on December 23, 2019.

Step 2 - Revised Definition

On February 14, 2019, the agencies published a proposed rule that would replace the 2015 rule and the pre-2015 regula­tions with an approach that incorporates elements of previous WOTUS case law and Justice Scalia’s plurality decision and Justice Kennedy’s concurring opinion in the Rapanos case. APPA supported of the proposed rule because it “properly emphasized clarity, regulatory certainty, and simplicity, and respected the limited powers of the executive branch under the Constitution and the CWA to regulate navigable waters.”

The agencies released a final rule in January 2020, which is very similar to the proposed rule and identifies four categories of jurisdictional WOTUS: (1) territorial seas and traditional navigable waters; (2) perennial and intermittent tributaries to those waters; (3) certain lakes and ponds, and impoundments of jurisdictional waters; and (4) wetlands adjacent to jurisdictional waters. The final rule excludes twelve categories of features, including ephemerals, groundwater, many ditches, and waste treatment systems (WTS).1

Of importance to public power utilities is the fact that the rule retains the long-standing WTS exclusion and clarifies that exclusion for the first time, providing a definition of a WTS and making two small ministerial edits. The term WTS includes all components, including lagoons and treatment ponds (such as settling or cooling ponds), designed to convey or retain, concentrate, settle, reduce, or remove pollutants, either actively or passively, from wastewater prior to discharge (or eliminating such discharge).


Legal Challenges

The 2015 WOTUS rule became the subject of intense litigation at the federal district and circuit court levels and, as a result, went into effect in 25 states (and the District of Columbia) while the pre-2015 regulation remained in place in the other 25 states. Litigation over whether the 2015 rule exceeded the agencies’ CWA authority is essentially on hold now as litigation over the repeal of the 2015 rule plays out. Some courts may be willing to place litigation on the 2015 rule on hold while the repeal rule litigation plays out. Other courts may simply dismiss challenges to the 2015 rule, based on the fact its repeal moots those challenges. Challenges to the repeal of the 2015 rule center around violations of the Administrative Procedure Act. The challengers argue that the agencies failed to follow their own scientific information on what constitutes the “significant nexus” standard laid out by the U.S. Supreme Court. Further legal action will likely be brought against the 2020 final rule once it has been published in the Federal Register.


Congressional Action

There have been numerous unsuccessful attempts in Congress to nullify or force EPA and the Corps to withdraw and re-propose the rule since it was finalized in 2015. Though the Trump Ad­ministration has repealed and replaced it, some opponents of the 2015 rule think legislative action will strengthen the 2020 rule when it is inevitably challenged in court. There have also been multiple attempts to include language in appropriations bills to prohibit funds from being used to implement the 2015 rule and amendments on other legislation (such as the farm bill) to repeal the rule. Most recently, at the beginning of the 116th Congress, Senator Rand Paul (R-KY) and Representative Jamie Herrera Buetler (R-WA) reintroduced similar bills, S. 376 and H.R. 667, respectively, that would define WOTUS as only waters that are “navigable in fact” or have permanent, standing, or continuously flowing water. It is unlikely that these attempts will succeed where others have failed.


American Public Power Association Position

APPA supports the new definition of WOTUS, which provides clarity and certainty, specifically lays out the exemptions, and protects the environment. The association supports the WTS definition, which clarifies a WTS need not perform active treat­ment for the exclusion to apply to the whole system. APPA also supports the replacement of “designed” with “used” in the WTS exclusion regulatory text, which clarifies that a CWA or state permit is not required to qualify for the WTS exclusion.


The Navigable Waters Protection Rule has four categories of jurisdictional waters:

Territorial Seas and Traditional Navigable Waters (TNW) — the rule would maintain jurisdiction over waters currently used, used in the past, or susceptible to use in interstate or foreign commerce, including territorial seas and waters subject to the ebb and flow of the tide.

Tributary — is a river, stream, or similarly naturally occur­ring surface water channel that contributes surface water flow to an TNW in a typical year either directly or through one or more tributaries or through wetlands. A tributary must be perennial (flowing continuously year-round) or intermittent (flowing continuously during certain times of the year and more than in direct response to precipitation) in a typical year. Alteration or relocation of a tributary does not remove jurisdiction so long as it continues to meet the conditions of this definition. It does not lose jurisdictional status if it contributes surface water flow to a downstream WOTUS through any of the following:

  • Channelized non-jurisdictional surface water feature;
  • Subterranean river;
  • Culvert, dam, tunnel, or similar artificial feature;
  • Debris pile, boulder field, or similar natural feature.

Includes a ditch that either relocates a tributary, is construct­ed in a tributary, or is constructed in an adjacent wetland so long as the ditch meets the flow requirements of this definition.

Lakes and Ponds and Impoundments — this is a new category intended to cover “round” standing bodies of open water that contribute surface water flow to an TNW in a typical year either directly or through one or more tributaries or wetlands. Again, it does not lose its jurisdictional status if it contributes surface water flow in a typical year through any of the following:

  • Channelized non-jurisdictional surface water feature;
  • Culvert, dike, spillway, or similar artificial feature;
  • Debris pile, boulder field, or similar natural feature.
  • Lakes, ponds, or impoundments are jurisdictional if they are inundated by flooding from a TNW through a lake or pond in a typical year.

Adjacent Wetlands — The rule maintains the longstand­ing wetland definition requiring all three wetland criteria to be satisfied. It finalizes a new definition of “upland” that complements the “wetland” definition by stating that an area is upland if it does not satisfy all three wetland criteria under normal circumstances and does not lie below the ordinary high-water mark or high tide line of a WOTUS. The final rule eliminates the longstanding concepts of bordering, con­tiguous, and neighboring. In addition, there are no numeric distance or floodplain requirements like those in the 2015 rule.