Colorado River

La Sal Mountain Loop on the Colorado River

The Colorado River is perhaps the most prominent of all interstate streams because it provides water to more than 40 million people in seven states and Mexico. The Colorado River is highly esteemed for both its iconic beauty and as a vital natural resource. It is often described as the most regulated river in the world with a complex and extensive history surrounding its development. The collection of agreements, federal laws, and court decisions that define how the river is managed is commonly referred to as “The Law of the River.”

Read the River Story

Utah’s Allocation

Each of the Upper Basin states (Colorado, New Mexico, Utah and Wyoming) and the Lower Basin states (Arizona, California and Nevada) has an appropriation of water for use by law. States can develop their respective allocations whenever the water is needed. Many Colorado River basin states have already developed their full Colorado River allocations – Utah has not.

Utah’s compact allocation is 1.725 million acre-feet of water or 23% of the water appropriated to the Upper Basin states. Considering climate variability, Utah only has plans to develop approximately 1.4 million acre-feet of water. The state is currently using about 1 million acre-feet.

Like other states with available Colorado River water, Utah has plans to develop more of its appropriation. Utah’s population is projected to double by 2065, placing an increased demand on water supplies. And the Colorado River is Utah’s most reliable water source.

A portion of Utah’s allocation (approximately 5%) is reserved for the Lake Powell Pipeline, a state project that will deliver water to Utah’s fast-growing Washington County. The project uses existing water rights, complies with the Law of the River, and was approved by state legislation.

Utah’s use of its Colorado River water does not compromise the legal appropriations of other states. The basin states have a long history of solving complex problems by working together while respecting state water rights in accordance with the Law of the River. That trend must continue for the benefit of the river and all who depend on it.

Chronology of Policy

Balancing river resources between states and other interests is an ever-evolving process, and this chronology of policy has expanded since the inception of the 1922 Colorado River Compact. View the Timeline

Colorado River Compact 1922: Negotiated by the seven basin states and the federal government, it defines the relationship between the Upper Basin states (Colorado, New Mexico, Utah and Wyoming) and the Lower Basin states (Arizona, California and Nevada) and protects each state’s right to develop its allocation on its own timeframe. Each basin has the right to develop and use 7.5 million acre-feet of river water annually.

Upper Colorado River Basin Compact 1948: Created the Upper Colorado River Commission and apportioned the Upper Basin’s 7.5 million acre-feet among Colorado (51.75%), New Mexico (11.25%), Utah (23%) and Wyoming (14%). The portion of Arizona that lies within the Upper Colorado River Basin was also apportioned 50,000 acre-feet annually.

Interim Guidelines (2007): The interim operational guidelines can be used to address the operations of Lake Powell and Lake Mead during drought and low reservoir conditions, and remain in effect through 2025. Reclamation is currently conducting a formal review to evaluate the effectiveness of the guidelines.

Drought Contingency Plan (2019): The Upper and Lower Colorado River Basin states have developed contingency plans both independently and collaboratively. The product of these discussions is five documents that comprise the Drought Contingency Plan (DCP) for the Colorado River. They are:

  1. Companion Agreement
  2. Upper Basin Drought Response Operations Agreement
  3. Upper Basin Demand Management Storage Agreement
  4. Lower Basin Drought Contingency Plan Agreement
  5. Lower Basin Drought Contingency Operations

Additional Resources

River Story – A visual snapshot of the Colorado River and its importance to Utah and its citizens.

Timeline – A timeline of Colorado River Compact and key events.

Water Use Reporting – There isn’t a national standard for calculating water use. Utah has a comprehensive way of measuring water use and includes all treated and untreated water. Find out what all goes into the state’s gallons per capita per day metric and how it’s used for planning purposes.