The Paradox Valley Unit was constructed to assist in meeting the objectives and standards of the Federal Water Pollution Control Act of 1948 (P.L. 80-845) and the Colorado River Basin Salinity Control Act of 1974, as amended and supplemented (P.L. 93-320). The Salinity Control Act authorizes the construction, operation, and maintenance of works in the Colorado River Basin to control the salinity of water delivered to users in the United States and Mexico.
The Paradox Valley Unit is located along the Dolores River in the Paradox Valley in Montrose County, Colorado, about ten miles east of the Colorado-Utah state line. The Dolores River is a major tributary to the Colorado River. The Paradox Valley was formed from the collapse of a salt anticline (dome). The unit is designed to prevent this natural salt load from entering the river and degrading the water quality of the main stem of the Colorado River.
Groundwater in the Paradox Valley is high in saline brine, and saline concentrations in this area have been measured in excess of 250,000 milligrams per liter, by far one of the most concentrated sources in the Colorado River Basin. Groundwater surfaces into the Dolores River and added more than 205,000 tons of salt annually to the Dolores River prior to operation of the Paradox Valley Unit.
The unit collects brine and injects it into deep geologic formations. The unit presently consists of a brine collection well field, brine surface treatment facility, brine injection facility, a 16,000-foot injection well, and associated roads, pipelines, and electrical facilities. Unit operations have been adjusted over time to address seismic activity and injection pressures. Under normal operations, the unit averages injection of about nine to ten million gallons of brine per month. The unit currently injects about 110,000 tons of salt per year that would have entered the Dolores River and in turn, degrade the water quality of the main stem of the Colorado River. The unit is one of the most effective salinity control projects in the Colorado River Basin and provides about ten percent of the total salinity control in the Colorado River.
Because the existing brine injection well is nearing the end of its useful life, another well or alternative brine disposal mechanism is needed for continued enhancement and protection of the quality of water available in the Colorado River for use in the United States and the Republic of Mexico, and to enable the United States to comply with its obligations under the agreement with Mexico of August 30, 1973.
The Bureau of Reclamation intends to prepare an environmental impact statement to identify and evaluate brine disposal alternatives to replace or supplement the existing Brine Injection Well No. 1 which has a projected useful life of three to five years under current operational parameters.
This website will be updated throughout the EIS process with the most current information related to the Paradox Valley Unit.
- Paradox Valley Unit EIS Scoping Report January 2013 [PDF]