News Release Archive

Colorado River Basin Water Supply and Demand Study Interim Report Available

Media Contact: Rose Davis, 702-293-8421, 06/06/2011 15:46
Lisa Iams, 801-524-3673,

For Release: June 06, 2011

The Bureau of Reclamation today released a report titled "Colorado River Basin Water Supply and Demand Study Interim Report No. 1." The reports and analysis prepared as components of the Study will better define options for future water management of the Colorado River Basin where climate change, record drought, population increases and environmental needs have heightened competition for scarce water supplies. The Colorado River Basin (Basin) was selected as one of the first three basin studies approved by the Bureau of Reclamation in September 2009.

"The Colorado River Basin Study is a feature of the Department of the Interior's WaterSMART program and is an integral part of our implementation of the SECURE Water Act," Reclamation Commissioner Michael L. Connor said today. "We are partnering on this valuable study with the seven Colorado River Basin States, in collaboration with other interested parties throughout the basin. Our goal is to provide detailed information for water resource managers, who face a complex future of increasing pressures on water supply matched with escalating demand for these finite water resources."

Reclamation's manager for the Study, Lower Colorado Region deputy regional director Terry Fulp, says the effort is significant and will consider multiple factors which will impact water supply and drive future demand: "In this study, we are considering the needs of all of the resources that are dependent upon a healthy river system, including water for municipal, industrial and agricultural use, hydroelectric power generation, recreation, fish and wildlife and water dependent ecological systems, under a broad range of conditions that could occur over the next 50 years," Fulp said today.

Given the high degree of uncertainty regarding future water supply and demand, a scenario planning process guided the development of scenarios to provide a broad range of future conditions. The interim report provides a quantified assessment of four water supply scenarios. These include scenarios based on historical observed and paleo-reconstructed streamflow records as well as future climate projections from global climate models. Consistent with Reclamation's recent report to Congress pursuant to the SECURE Water Act of 2009, this Study finds that for the climate change scenario, the mean natural flow of the Colorado River as measured at Lees Ferry, Arizona is projected to decrease by approximately nine percent over the next 50 years.

The Study also anticipates increases in the frequency and severity of droughts. Further review and investigations of these results will be conducted as the Study progresses.

The four water demand scenarios were developed to incorporate plausible future trends related to demographics and land use, technology and economics, and socio-political factors.

Preliminary metrics were also developed for assessing the Colorado River system's future reliability under the four water supply and demand scenarios.

The next phases of the ongoing study will be directed toward quantifying the demand scenarios, assessing future system reliability, and the development and evaluation of opportunities for balancing supply and demand. Additional interim reports will be published with a final report targeted for summer of 2012.

The interim report provides a comprehensive snapshot of the initial effort to define current and future imbalances in Colorado River water supply and demand over the next 50 years in the Colorado River Basin and the adjacent areas of the seven Colorado River Basin States that receive Colorado River water.

Comments are welcome through the process described at the web page listed below. The report is available online at

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