navigable water, in the broadest sense, a stream or body of water that can be used for commercial transportation. When, as in the early common law, the term is restricted to waters affected by tides, it denotes only the open sea and tidal rivers. In most U.S. jurisdictions the definition tends to include any body of water that may be put to public use, e.g., streams that can be used only for logging and for small pleasure boats would still be considered navigable. In the United States each state determines what private use may be made of wholly intrastate navigable waters (see water rights), but the federal government alone has authority over navigable interstate and international waters. In general, if the water is of restricted navigability, the right of public use is strictly confined to transporting goods; use of the water for irrigation, power, and the like is limited to the abutting landowners.
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