Tidelands

Tidelands are the territory between the high and low water tide line of sea coasts, and lands lying under the sea beyond the low-water limit of the tide, considered within the territorial waters of a nation. The United States Constitution does not specify whether ownership of these lands rests with the federal government or with individual states. Originally little commercial value was attached to tidelands, so ownership was never firmly established, but the coastal states generally proceeded as if they were the owners. Some states, such as Mississippi, directly administer these lands under the public trust doctrine.

The question arose for federal nations whether the tidelands for formerly independent coastal states had been ceded to the federal union on admission, or retained. The admission of the former Republic of Texas as a state in the United States in 1845 stipulated that its tidelands remained the territory of Texas. This has been an issue for oil and natural gas leases and federally funded development that affects such tidelands.

For other states that were formerly independent, such as the Thirteen Colonies, there was no explicit retention of state sovereignty and the federal government had long asserted its own sovereignty over their tidelands.

The value of tidelands increased when it became known that vast oil and natural gas deposits lay within their limits and that modern technology made retrieval of these minerals commercially profitable. The first offshore oil well in the Gulf of Mexico began production in 1938 in shallow water one mile (1.6 km) off the Louisiana coast; in 1947, a second well began to operate off the coast of Terrebonne Parish, also in Louisiana.

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