Upper Mississippi water resource region

The Upper Mississippi 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 Upper Mississippi region, which is listed with a 2-digit hydrologic unit code (HUC) of 07, has an approximate size of 189,968 square miles (492,010 square kilometers), and consists of 14 subregions, which are listed with the 4-digit HUCs 0701 through 0711. In a 1975 report, the region was described as "rich in water - surface water is plentiful, and ground water is a large, important, and manageable resource."[3]

This region includes the drainage of the Mississippi River Basin above the confluence with the Ohio River, excluding the Missouri River Basin. Includes parts of Illinois, Indiana, Iowa, Michigan, Minnesota, Missouri, South Dakota, and Wisconsin.[4]

The Upper Mississippi region, with its 14 4-digit subregion hydrologic unit boundaries.
  1. ^ "Science in Your Watershed - Locate Your Watershed". USGS. Retrieved 2016-10-12. Public Domain This article incorporates text from this source, which is in the public domain.
  2. ^ "Hydrologic Unit Maps". USGS. Retrieved 2016-10-12. Public Domain This article incorporates text from this source, which is in the public domain.
  3. ^ Bloyd, R. M. (1975). Summary appraisals of the nation's ground-water resources – Upper Mississippi region (PDF) (Report). Washington, D.C.: U.S. Geological Survey. doi:10.3133/pp813b. Retrieved 2023-09-13.
  4. ^ "Boundary Descriptions and Names of Regions, Subregions, Accounting Units and Cataloging Units". USGS. Retrieved 2016-10-12. Public Domain This article incorporates text from this source, which is in the public domain.