Tidal Waters Legal Definition: Bodies of water within a state's territorial waters and that are subject to the ebb and flow of ordinary tides, whether navigable or not, and usually excluding harbors or lakes. Related Terms: High Seas , Continental Shelf , Territorial Sea A term of international law and of maritime law by which a coastal state will distinguish that part of the water adjacent to the coast which extends between the high and low tide mark, and for a variety of purposes such as, but not limited to, jurisdiction, property rights, environmental regulation, fishing, transportation or construction. Some states, such as England, further distinguish tidal waters by referring to the high and low tides in Spring. §255 of the Merchant Shipping Act 1995 states: "Tidal water means any part of the sea and any part of a river within the ebb and flow of the tide at ordinary spring tides, and not being a harbour." Other jurisdictions prefer the term tide water. Bouvier, in his 1897 American law dictionary, wrote: "Tide-water is not limited to water which is salt, but embraces, also, so much of the water of fresh rivers as is propelled backwards by the ingress and pressure of the tide." REFERENCES: Merchant Shipping Act 1995, UK Public Acts 1995, Chapter 21 Categories & Topics: Duhaime & Williams Maritime & Waterways Law Dictionary Unless otherwise noted, this page was written by Lloyd Duhaime of Duhaime.org Always looking up definitions? Save time with our search provider (modern browsers only) If you find an error or omission in Duhaime's Law Dictionary, or if you have suggestion for a legal term, we'd love to hear from you!