A14_MR_Attachment_3_Regions_Map_Commodity_Internet_BPA_1.jpg

This is a reference map showing the 12 Interior Region Names Based on Watersheds as established by the U.S. Department of the Interior and U.S. Geological Survey, effective October 18, 2019. The map delineates the continental United States into 12 distinct interior regions, each named after major watershed basins: Columbia-Pacific Northwest (Region 9), California-Great Basin (Region 10), Upper Colorado Basin (Region 7), Lower Colorado Basin (Region 8), Missouri Basin (Region 5), Upper Mississippi (unlabeled), Mississippi Basin (Region 4), Arkansas-Rio Grande-Texas-Gulf (Region 6), Arkansas-White-Red (unlabeled), South Atlantic-Gulf (Region 2), Great Lakes (Region 3), and North Atlantic-Appalachian (unlabeled). Additionally, two separate regions are identified: Alaska (Region 11) and Pacific Islands (Region 12), which includes Hawaii, Guam, Commonwealth of the Northern Mariana Islands, and American Samoa. A separate inset indicates Puerto Rico and U.S. Virgin Islands as Region 2.

This map serves as a standardized geographic framework for federal water resource management and interagency coordination. The watershed-based regional organization facilitates unified planning, monitoring, and environmental stewardship across multiple states and jurisdictions within each basin. Federal agencies use this regional structure for water resource allocation, environmental protection initiatives, and inter-regional collaboration on hydrological management and conservation projects.