On December 11, 2018 the Environmental Protection Agency (EPA) and the Department of the Army published a revised definition of "Waters of the United States" (WOTUS) that clarifies federal authority under the Clean Water Act.

The waters of the U.S. can trace its beginning back to 1972 Federal Water Pollution Control Act (FWPCA) Amendments. These amendments defined the term waters of the U.S, as waters regulated under the Clean Water Act (CWA). There have been numerous court cases and hearings dedicated to the definition of waters of the U.S., and highlights of these cases are summarized below:

  • 2006: Supreme Court Case introduced the concept that waters with a significant nexus to navigable waters are covered under the CWA. It also stated that waters of the U.S. include only those relatively permanent, standing or continuously flowing bodies of water forming geographic features that are described in ordinary parlance such as streams, oceans, rivers, and lakes. This caused a lot of confusion and uncertainty in the jurisdiction of the CWA.
  • 2015: EPA and U.S. Army Corps of Engineers finalized the Clean Water Rule, which revised the definition of WOTUS to broaden the definition of what was considered a waters of the U.S.
  • 2017: Executive Order instructed the EPA and U.S. Army Corps of Engineers to repeal and revise the 2015 rule.
    • EPA and U.S. Army Corps of Engineers then published a new rule delaying the effective date of the 2015 rule until 2020.
    • The rule delaying the effective date of the 2015 rule was then vacated by the U.S. District Court for the District of South Carolina (do we know why??).

However, the 2015 Clean Water Act Rule was already in effect in approximately half the country (22 states). In the other 28 states, the pre-2015 regulations and guidance are currently in effect.

The proposed definition that was announced on December 11, 2018, would replace the 2015 Rule and the pre-2015 regulations. The proposed rule rolls back the definitions of certain waters that previously were included in the WOTUS definition, thereby limiting CWA authority. The other significant change in the proposed rule, is that waters of the U.S. is limited to be defined as those that are physically and meaningfully connected to traditional navigable waters. This essentially eliminates the significant nexus determination established in 2006.

The following table summarizes the major changes in the proposed rule compared to the 2015 rule and pre-2015 practice:

Category of WaterProposed Changes
Adjacent WetlandsUnder the proposed rule, in order to be defined as a waters of the U.S., wetlands must be adjacent to a major body of water or connected to a major waterway by surface water. Wetlands that are separated from tributaries by land, dikes or other features are not onsidered a waters of the U.S. under the proposed rule.
DitchesThis is a new category defined in the proposed rule under WOTUS, and are defined as "an artificial channel used to convey water". In order to be defined as a WOTUS, ditches would need to be a traditional navigable water or subject to the ebb and flow of the tide. If a ditch meets the tributary definition as proposed in this new rule, it will also be defined as a WOTUS. It is important to note that ditches not covered by this newly proposed category could still be regulated under the CWA and subject to permitting requirements if they meet the definition of point source in CWA 502(14)
ImpoundmentsNo changes.
Interstate WatersNo longer an independent category of jurisdictional waters under the proposed rule; considered a WOTUS if they satisfy the conditions of another category of jurisdictional waters. Interstate waters without any connection to traditional navigable waters are now required to be regulated at the state level.
Lakes and PondsThis is a new category defined in the proposed rule under WOTUS. In the proposed rule, lakes and ponds are considered waters of the U.S. under the following conditions (1) they are traditional navigable waters. (2) They contribute to a traditional navigable water (directly or indirectly). (3) The lake or pond is flooded in a typical year by a waters of the U.S.
Territorial SeasIn the proposed rule, territorial seas are now identified as a type of traditional navigable water.
TributariesIn the proposed rule, tributaries are defined as rivers and streams that flow to traditional navigable waters. As defined, these channels must flow more often than when it just rains (i.e. must be perennial or intermittent). Under the proposed definition, a tributary is considered a waters of the U.S. if it flows through a culvert, dam, or other similar artificial break or through a debris pile, boulder field, or similar natural break so long as the artificial or natural break conveys perennial or intermittent flow to a tributary or other jurisdictional water at the downstream end of the break.  Ephemeral flows, dry washes, arroyos and similar features are not defined as tributaries under the proposed rule as these types of features lack the perennial or intermittent flow required to satisfy the proposed definition. The proposed rule also includes proposed definitions for perennial, intermittent, typical year and ephemeral.

Listed below are highlights of what the proposed rule describes as not being covered under the WOTUS definition:

  • Ephemeral streams that flow only after heavy rains or during snow melt
  • Groundwater
  • Ditches that do not meet the proposed definitions to be regulated
  • Prior converted cropland
  • Storm water control features excavated or constructed in upland to convey, treat, infiltrate, or store storm water run-off
  • Wastewater recycling structures
  • Waste treatment systems
  • Waters not included in the proposed categories in the table above

Comments are being requested on the following items, among other aspects found in the proposed rule:

  • Whether existing guidance regarding the scope of traditional navigable waters should be updated to help improve clarity of the proposed rule.
  • The proposed removal of interstate waters as a separate regulated category in the rule.
  • Whether certain categories of impoundments should not be jurisdictional, such as certain types of impoundments that release water downstream infrequently or impede flow downstream such that the flow is less than intermittent.
  • Whether the definition of tributary be limited to perennial waters only.
  • How effluent-dependent streams should be treated under the proposed tributary definition.
  • Whether streams that contribute less than intermittent flow to a traditional navigable water or territorial sea, be included in the tributary definition as proposed.
  • The proposed definition of ditch, perennial, intermittent, typical year and ephemeral among others.
  • The proposed interpretations of adjacency in regard to the wetlands category.
  • Tools that may be helpful in the implementation of the proposed wetlands category (NRCS Soil Surveys, tidal gauge data, site-specific modeling, etc.)

The rule will be open for comment for 60 days after it is published in the Federal register. A public listening session will be held by EPA and the U.S. Army on January 23, 2019 at the Reardon Convention Center in Kansas City, KS. For more information on the history of the WOTUS, visit EPA's website.

If you are interested in learning more about this proposed rule or have questions on how this proposed rule may affect water permitting at your facility; please contact the Trinity office closest to you at (800) 229-6655.