South Atlantic-Gulf Water Resource Region

The South Atlantic-Gulf Water Resource Region is one of 21 major geographic areas, or regions, in the first level of classification used by the United States Geological Survey to divide and sub-divide the United States into successively smaller hydrologic units. These geographic areas contain either the drainage area of a major river, or the combined drainage areas of a series of rivers.

The South Atlantic-Gulf region, which is listed with a 2-digit HUC code of 03, has an approximate size of 279,664 square miles, and consists of 18 sub-regions, which are listed with the 4-digit HUC codes of 0301 through 0318.

This region includes the drainage that ultimately discharges into: (a) the Atlantic Ocean within and between the states of Virginia and Florida; (b) the Gulf of Mexico within and between the states of Florida and Louisiana; and (c) the associated waters. The geographic area of the South Atlantic-Gulf region includes all of Florida and South Carolina, and parts of Alabama, Georgia, Louisiana, Mississippi, North Carolina, Tennessee, and Virginia.

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