Upper Colorado River Basin regional water availability assessment timeline

Integrated Water Availability Assessments (IWAAs) examine how much water is available in the United States and identify where and when the Nation may have challenges meeting its demand for water. These assessments evaluate water quantity and quality in both surface and groundwater, as related to human and ecosystem needs and as affected by human and natural influences. Some regional water availability assessments are conducted in medium-sized watersheds that are representative of larger regions throughout the Nation, known as Integrated Water Science (IWS) basins.

The Upper Colorado River Basin (UCOL) Regional Water Availability Assessment is divided into two phases. Phase 1 of the Regional Water Availability Assessment, which formally began in 2021, will last five years and will focus on addressing a regionally relevant threat to water availability. Phase 2 of the assessment will begin in 2026, will last five years, and will include a broader regional evaluation of water supply and demand.