The Tennessee 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 Tennessee region, which is listed with a 2-digit hydrologic unit code (HUC) of 06, has an approximate size of , and consists of 4 subregions, which are listed with the 4-digit HUCs 0601 through 0604.
This region includes the drainage of the Tennessee River Basin. Includes parts of Alabama, Georgia, Kentucky, Mississippi, North Carolina, Tennessee, and Virginia.