Confluence (geography)

In geography, a confluence is the meeting of two or more bodies of water. Also known as a conflux, it refers either to the point where a tributary joins a larger river, (main stem), or where two streams meet to become the source of a river of a new name, such as the confluence of the Monongahela and Allegheny rivers in Pittsburgh, Pennsylvania creating the Ohio River.

The term is also used to describe the meeting of tidal or other non-riverine bodies of water, such as two canals or a canal and a lake. A one-mile (1.6 km) portion of the Industrial Canal in New Orleans accommodates the Gulf Intracoastal Waterway and the Mississippi River-Gulf Outlet Canal; therefore those three waterways are confluent there.

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