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Russell W. Wilson
Russell W. Wilson

Clean Water Rule

By Russell W. Wilson

Definition of “Waters of the United States” Under the Clean Water Act (CWA)


The terms “waters of the United States” and “navigable waters of the United States” are two separate definitions applied by the United States Army Corps of Engineers (Corps) in different contexts pursuant to different statutes.

Let us suppose you want to construct a hydroelectric plant. A fundamental concern would be whether the newly constructed generating facility and dam would obstruct navigation.

In that context, the jurisdiction of the Corps would turn on whether the particular body of water meets the definition of the “navigable waters of the United States” pursuant to the Rivers and Harbors Act of 1899 (RHA).

The regulatory definition of the “navigable waters of the United States” means:
“…those waters of the United States that are subject to the ebb and flow of the tide and/or are presently used, or have been used in the past, or may be susceptible for use to transport interstate or foreign commerce. A determination of navigability, once made, applies laterally over the entire surface of the waterbody, and is not extinguished by later actions or events which impede or destroy navigable capacity.” (33 C.F.R. § 329.4)

The RHA and the “navigable waters of the United States” are concerned with navigation and navigation in the traditional sense.

This article is not about navigation in the traditional sense. Rather, our purpose here is to explore the meaning of the “waters of the United States” under the Clean Water Act (CWA).

Click here to read the full Badger Common’Tater article.

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