Seven States of the Colorado River Basin

The Colorado River Compact (1922) divides the basin between Upper Basin and Lower Basin states—seven total:

Upper Basin (4)

• Colorado (headwaters)
• New Mexico
• Utah
• Wyoming

Lower Basin (3)

• Nevada
• Arizona
• California

Key Facts

• Each basin allocated 7.5 MAF/yr (million acre-feet)
• Mexico gets 1.5 MAF/yr (1944 Treaty)
• River serves 40M+ people, 5.5M acres agriculture
• Major reservoirs: Lake Powell (UT/AZ), Lake Mead (NV/AZ)
• Current crisis: 23-year megadrought + overallocation → Tier 1/2 shortages

Management: Bureau of Reclamation, Upper Colorado River Commission, state water agencies.