San Juan/Dolores River Basin

The San Juan/Dolores Basin is located in the southwest corner of Colorado, covering an area approximately 10,169 square miles (9.7 percent of the area of Colorado). In addition to San Juan and Dolores Rivers, major tributaries include San Miguel River, Animas River, and La Plata River.
Quick Facts
Description Value (approximate)
Irrigated Acres (2010) 1                  228,880

                 Irrigated Lands Graph
Decreed Points of Diversion 1 6,965
Decreed Wells 1 1,900
Major Reservoirs 2
  • McPhee Reservoir
  • Vallecito Reservoir
  • Lemon Reservoir
Normal Storage (acre-feet)
  • 381,100
  • 129,700
  • 40,100
Major Imports into Basin 2

Major Exports from Basin 2
  • San Juan-Chama Project
Average Annual Diversion (acre-feet)
  • 89,832

1 Source: CDSS, total values derived from GIS Data for San Juan/Dolores Basin
2 Source: Statewide Water Supply Initiative Fact Sheet for San Juan/Dolores Basin, CWCB, 2006

Compact Facts
  • Colorado River Compact of 1922:  The Colorado River Compact allocates 7.5 million acre-feet (AF) of consumptive use annually to:
    1. the Upper Colorado River Basin (those parts of Arizona, Colorado, New Mexico, Utah, and Wyoming above Lee Ferry, Arizona), and
    2. the Lower Colorado River Basin (those parts of Arizona, California and Nevada below Lee Ferry, Arizona).
  • Upper Colorado River Basin Compact of 1948:  The Upper Colorado River Basin Compact allocates the 7.5 million AF apportionment of consumptive uses available to the Upper Basin as follows:
    • Arizona – 50,000 AF/year
    • Colorado – 51.75%
    • Utah – 23%
    • Wyoming – 14%
    • New Mexico – 11.25%

     San Juan/Dolores River Basin

Basin Updates
  • No updates at this time

 Additional Information