6/29/2011 Gallup Independent: 9 percent decrease in Colorado River flow projected By Kathy Helms, Dine Bureau: WINDOW ROCK – The average natural flow of the Colorado River as measured at Lees Ferry will decrease by approximately 9 percent over the next 50 years, according to a Bureau of Reclamation study. In addition, the average yield of the river could be reduced by 10 to 20 percent due to climate change. The “Colorado River Basin Water Supply and Demand Study Interim Report No. 1,” released June 6, also anticipates increases in the frequency and severity of droughts. The Colorado River Basin is one of the most critical sources of water in the West. The seven basin states include some of the fastest-growing urban and industrial areas in the United States. The river is the lifeblood for at least 15 Native American tribes, seven national wildlife refuges, four national recreation areas, and five national parks. Its tributaries provide municipal water to 30 million people and irrigation for nearly 4 million acres of land.
Water supply and demand imbalances already exist in some areas of the basin and are projected to increase in the future. Storage capacity of approximately four times the average inflow has helped offset demands in periods of sustained drought, such as is currently being experienced, according to Reclamation.
The ongoing study will assess water supply and demand throughout the study area through 2060 and the reliability of the Colorado River system to meet the needs of basin resources, such as water allocations and deliveries under the Law of the River.
The study, begun in January of 2010, is a collaborative effort with interested parties throughout the basin. Reports and analysis prepared as part of the study will help define options for future water management of scarce water supplies.
The interim report provides a comprehensive snapshot of the initial effort to define current and future imbalances in over the next 50 years. Reclamation is seeking comment on the interim report by July 8. Additional interim reports will be published with a final report targeted for July 2012.