Last week, the U.S. Environmental Protection Agency (EPA) and Army Corps of Engineers (Corps) released their much-anticipated draft proposed rule to re-write the definition of “waters of the United States” (WOTUS) (“2018 Rule”). The definition of WOTUS establishes the scope of agency jurisdiction over waters and wetlands under the Clean Water Act (CWA). This 2018 Rule follows years of uncertainty as to the scope of CWA jurisdiction that has included nationwide litigation and multiple Supreme Court decisions. Overall, the 2018 Rule represents a narrower reading of jurisdiction compared with the 2015 WOTUS rule issued by the Obama administration (“2015 Rule”). This narrower interpretation of jurisdiction represents regulatory relief for private landowners, but the rule is likely to face years of legal challenges before final interpretation, as did the 2015 Rule.


The CWA regulations and restrictions apply only to “navigable waters.” However, “navigable waters” has a broader reach than its ordinary meaning and is defined under the CWA to mean “any waters of the United States, including territorial seas.” 33 U.S.C. § 1362(7). In response to various challenges and Supreme Court cases, the EPA and Corps have revised the regulations implementing the WOTUS definition over the years.

The new proposal harkens back to Justice Scalia’s opinion in the 2006 Supreme Court decision Rapanos v. United States. In a rare 4-1-4 ruling, Justice Scalia issued the plurality opinion on behalf of four justices that would restrict WOTUS regulations to waters that are “relatively permanent” and have a “continuous surface connection” with navigable waters. On the other hand, Justice Kennedy’s standard was that areas would need to have a “significant nexus” with navigable waters to be jurisdictional. Most courts have held that Justice Kennedy’s “significant nexus test” was the controlling precedent from the Rapanos case.

Prior to 2015, jurisdiction primarily covered waters with an effect on interstate or foreign commerce: navigable waters, interstate waters, territorial seas, tributaries, and adjacent wetlands. Under the Obama administration, the EPA and Corps proposed revisions to the WOTUS definition in the 2015 Rule. The agencies claimed the 2015 Rule proposed only minor changes to existing rules and would bring their interpretation in line with Justice Kennedy’s opinion, but many saw the revised definition as dramatically expanding the jurisdiction of the CWA, particularly in regard to isolated, seasonal, and ephemeral waterways or wetlands. Because of the potentially far-reaching impacts, the 2015 Rule faced immediate backlash from farmers, ranchers, timberland owners, homebuilders, developers, and other private landowners. Subsequently, the Trump administration delayed and repealed the 2015 Rule, though courts later deemed that effort invalid, leaving a patchwork of different applicable WOTUS rules across the country. As of now, the 2015 Rule still applies in Oregon and Washington, whereas pre-2015 regulations apply in Idaho and other states. The new 2018 Rule, if finalized, would supersede the 2015 Rule, bringing the WOTUS definition more in line with Justice Scalia’s definition and providing nationwide uniformity.

2018 Draft Proposed Rule

The EPA and Corp’s new proposed WOTUS rule includes some of the same jurisdictional categories as previous rules while modifying and eliminating jurisdiction over others. For example, the following categories will continue to fall under the jurisdiction of the CWA:

  • Traditional navigable waters, such as large rivers and lakes used in interstate or foreign commerce
  • Tributaries to those navigable waters, including rivers or streams that are perennial or intermittent in a “typical year”
  • Interstate waters 

The new proposed rule eliminates or modifies WOTUS jurisdiction in the following categories:

  • Ephemeral streams, those created only as the result of rainfall, would no longer be jurisdictional.
  • Most ditches, defined as an “artificial channel used to convey water,” would be non-jurisdictional, including agricultural ditches. Ditches would be jurisdictional only where they qualify as traditional navigable waters, are subject to the ebb and flow of the tide, are constructed in a tributary, or are built in adjacent wetlands.
  • Lakes and ponds would be jurisdictional only where they are traditional navigable waters or contribute perennial or intermittent flow to a traditional navigable water.
  • Only “adjacent wetlands” would be jurisdictional. Wetlands are adjacent where they physically touch or have a continuous surface connection with other jurisdictional waters, or there is perennial or intermittent flow between the wetland and a jurisdictional water. Differing from the 2015 Rule, wetlands that are separated from jurisdictional waters by a berm or levee and lack a surface water connection would not be jurisdictional.
  • Groundwater, prior converted cropland, and wastewater recycling and treatment systems are all defined and specifically excluded from jurisdiction. 

The most notable changes between the 2015 Rule and the 2018 Rule are (1) the removal of jurisdiction over ephemeral streams, (2) the restricted definition and requirements for adjacent wetlands, (3) the reoccurring requirement for a “surface water connection” for various categories of waterways, and (4) the explicit exclusion of groundwater, effectively sidestepping recent court decisions that held groundwater subject to CWA jurisdiction. Note that this proposed rule is still only in draft form, and the agencies could make changes when they issue a final proposed rule. For example, in issuing the draft rule, the agencies specifically requested public comment on whether or not they should maintain the protections for intermittent streams in the draft proposed rule. Some argue this hints that the agencies may later propose to remove protections for intermittent streams. See the link to this infographic from the EPA.

Next Steps

Overall, the draft 2018 Rule addresses many concerns raised by critics regarding the 2015 Rule, including by limiting or removing jurisdiction over ephemeral streams, small or isolated ponds, and upland wetlands. Additional details and the actual text of the draft proposed rule are available here. The draft 2018 Rule will be published in the Federal Register and available for 60 days of public comment. After considering public comment, the agencies may make changes prior to issuing a final rule. Legal challenges will likely ensue and may prevent the rule from going into effect for some time.

In the meantime, despite what happens with the WOTUS rule, landowners will still be subject to regulatory procedures and permit requirements under applicable state law. For example, Oregon and Washington both regulate “waters of the state,” which includes a much broader mix of waters and areas. While regulations from state agencies will still apply, the 2018 Rule, if finalized, provides valuable regulatory relief from federal permitting requirements.

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