Water quality in the Colorado River affects all beneficiaries of the water from the aquatic ecosystem to municipal, industrial, and agricultural users to recreationists. The Colorado River Storage Project (CRSP) reservoirs have a large influence on water quality in the Colorado River. Reclamation directs and participates in studies to monitor and improve water quality in the Colorado River Basin.
One of the long recognized water quality concerns of the Colorado River is salinity, which affects agricultural, municipal, and industrial use in both the United States and Mexico. Congress has enacted several Acts related to investigating, monitoring, and implementing measures to deal with the salinity concerns of the Colorado River. For more information on the Salinity Control Program, visit Reclamation's Salinity Control Program website.
In addition to salinity, other water quality constituents are monitored on the Colorado River and its tributaries and in the storage reservoirs. A network of 20 stream gages and field sampling activities are funded in full or in part by Reclamation. In the CRSP reservoirs, water quality constituents are monitored through regular sampling programs. At Lake Powell, for example, water quality monitoring is funded by Reclamation and performed by the USGS in cooperation with Reclamation and the National Park Service. Monitoring is conducted monthly for samples above and below the dam and quarterly for lake-wide samples. This monitoring provides valuable information for programs such as the Glen Canyon Dam Adaptive Management Program.
The activities relating to water quality are summarized in the report from the Secretary of the Interior to Congress and the states of the Colorado River Basin known as the “Quality of Water Colorado River Basin Progress Report”, which has been issued every two years since 1963. The most recent report is Progress Report 22.