navigable water. 1. At early common law, any body of water affected by the ebb and flow of the tide. • This test was first adopted in England because most of England’s in-fact navigable waters are influenced by the tide, unlike the large inland rivers that are capable of supporting commerce in the United States. — Also termed boatable water. [Cases: Navigable Waters 1.C.J.S. Navigable Waters § 1.]

“In addition to its bearing on admiralty jurisdictional inquiries, the navigable waters issue comes up in cases involving the scope of Congress’s regulatory authority under the commerce clause; the validity and interpretation of a variety of statutes and regulations administered by the

Coast Guard; the powers of the Corps of Engineers over waterways, dams, marinas, etc., under the Rivers & Harbors Act and other statutes; the Federal Power Commission’s authority to inspect and license electricity-generating dams; the existence and exercise of a servitude of navigation, which affects both public access to waterways on private land and governmental regulatory authority over such waters; and disputes over the ownership of stream beds. The foregoing is not an exhaustive listing. Well over a thousand federal statutes use the term ‘navigable waters.’ ” David W. Robertson, Steven F. Friedell & Michael F. Sturley, Admiralty and Maritime Law in the United States 53 n.1 (2001).

2. (usu. pl.) A body of water that is used, or typically can be used, as a highway for commerce with ordinary modes of trade and travel on water. • Under the Commerce Clause, Congress has broad jurisdiction over all navigable waters of the United States. [Cases: Navigable Waters 1.

C.J.S. Navigable Waters § 1.]

navigable water of the United States.Navigable water that alone — or in combination with

other waters — forms a continuous highway for commerce with other states or foreign countries

[Blacks Law 8th]