The Great Basin 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.[1][2]
The Great Basin region, which is listed with a 2-digit HUC code of 16, has an approximate size of 141,717 square miles (367,050 square kilometers), and consists of 6 subregions, which are listed with the 4-digit HUC codes of 1601 through 1606.[3]
This region includes the drainage of the Great Basin that discharges into the states of Utah and Nevada. This includes parts of California, Idaho, Nevada, Oregon, Utah, and Wyoming.[4]