Federal agencies define “waters of the United States”

NOTE: This article has been updated to include a technical clarification.   

On May 27, 2015, the U.S. Environmental Protection Agency and Army Corps of Engineers issued their Clean Water Rule, defining the term “waters of the United States” (WOTUS) for purposes of Clean Water Act jurisdiction (Docket No. EPA-HQ-OW-2011-0880). The Agencies indicate that the rule defining WOTUS clarifies their jurisdiction to implement the Clean Water Act in the context of several US Supreme Court decisions. The final rule can be found in the June 29, 2015 issue of the Federal Register (Vol. 80, No. 124, pp. 37054-37127; http://www.regulations.gov/#%21documentDetail;D=EPA-HQ-OW-2011-0880-20862).

While the Clean Water Rule itself is rather brief (several three-column pages), the preamble is approximately 50 pages in length, illustrating the complexity of the Rule. The Rule creates three classifications of waters: (1) waters that are jurisdictional in all instances by rule (categorical WOTUS); (2) waters that are subject to case-specific analysis to determine jurisdiction; and, (3) waters that are excluded from jurisdiction by rule.

Six categories of waters are designated as jurisdictional by rule:

  1. Traditional navigable waters (“All waters which are currently used, were used in the past, or may be susceptible to use in interstate or foreign commerce, including all waters which are subject to the ebb and flow of the tide”)
  2. All interstate waters, including interstate wetlands
  3. The territorial seas
  4. All impoundments of waters otherwise identified as WOTUS
  5. All tributaries, as defined in the final rule
  6. All waters adjacent to one of the above water features, including wetlands, ponds, lakes, oxbows, impoundments, and similar waters

The Rule acknowledges that the great majority of tributaries as defined by the Rule are headwater streams. Ditches also will be jurisdictional if they meet the definition of “tributary” and are not excluded.

“Adjacent” waters includes those “bordering, contiguous, or neighboring” categories 1 through 4 above, even if separated from those waters by “constructed dikes or barriers, natural river berms, beach dunes and the like.”

“Neighboring” waters include those located in whole or part within the 100-year floodplain and that are within 1500 feet of the ordinary high water mark of a traditional navigable water, interstate water, territorial sea, impoundment, or a tributary.

The preamble of the Rule states that “adjacent waters” do not include waters subject to established normal farming, silviculture, and ranching activities as those terms are used in Section 404(f) of the Clean Water Act.  

“Other waters” determined on a case-specific basis to have a “significant nexus” to a traditional navigable water, interstate water, or territorial sea also will be jurisdictional. The Rule identifies five specific types of other waters for which there is no need for a case-specific finding and, therefore, they should be analyzed “in combination” (as a group, rather than individually) when determining if they are jurisdictional: 

  • Prairie potholes
  • Carolina bays and Delmarva bays
  • Pocosins
  • Western vernal pools
  • Texas coastal prairie wetlands

The Clean Water Rule also indicates that waters within the 100-year floodplain of a traditional navigable water, interstate water, or the territorial seas, or within 4,000 feet of an ordinary high water mark may have a significant effect on downstream waters. These waters should be evaluated individually or in combination to determine if they are jurisdictional.

Several waters and features are excluded from jurisdiction in the Clean Water Rule, even if they otherwise qualify for jurisdiction under the tributary, adjacent, or other waters categories discussed above. Examples include prior converted cropland, waste treatment systems, and log ponds. The Rule states that it retains existing exclusions from the definition of WOTUS, and that “several exclusions reflecting longstanding agency practice are added to the regulation for the first time.”

NCASI staff continue to assess the Rule and its implications for forest management and manufacturing operations. Members seeking a more detailed analysis of the Waters of the U.S. Rule should obtain NCASI Corporate Correspondent Memorandum 15-007, which is available from NCASI’s website (www.ncasi.org).

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