Ebb and Flow Law and Legal Definition

Ebb and flow means the coming in or increasing and going out or decreasing of tide. This expression was at one time used to identify the limits of admiralty jurisdiction. It serves as one of the test for determining whether bodies of water are navigable waters of the U.S. Depending upon the ebb and flow, river can be classified as navigable and not navigable. Navigable is one that is extending as high as the sea ebbs and flows and belonging to the king and not navigable being such when the sea does not ebb or flow and belonging to the landholders on each side. Consequently, the river changes its character at the point where the tide ceases to ebb and flow.

In Hooker v. Cummings, 20 Johns. 90 (N.Y. 1822), the court observed that “The common law of England considers a river in which the tide ebbs and flows an arm of the sea and as navigable and devoted to the public use for all purposes as well for navigation as for fishing. It also considers other rivers in which the tide does not ebb and flow as navigable but not so far belonging to the public as to divest the owners of the adjacent banks of their exclusive rights to the fisheries therein.”