Department of the Interior Releases Report
Highlighting Impacts of Climate Change
to Western Water Resources

Impacts of Climate Change to Western Water Resources

Map of Impacts to Western Water Resources
 

http://www.usbr.gov/climate/

Climate Change

April 25, 2011

Interior Releases Report Highlighting Impacts of Climate Change to Western Water Resources - This report assesses climate change risks and how these risks could impact water operations, hydropower, flood control, and fish and wildlife in the western United States. The report to Congress represents the first consistent and coordinated assessment of risks to future water supplies across eight major Reclamation river basins, including the Colorado, Rio Grande and Missouri river basins.

SECURE Water Act Section 9503(c) — Reclamation Climate Change and Water 2011 (PDF - 3.54 MB)
http://www.usbr.gov/climate/SECURE/docs/SECUREWaterReport.pdf [Full copy of the report.]

West-Wide Climate Risk Assessments: Bias-Corrected and Spatially Downscaled Surface Water Projections (PDF - 2.17 MB)
http://www.usbr.gov/WaterSMART/docs/west-wide-climate-risk-assessments.pdf

News Release: Interior Releases Report Highlighting Impacts of Climate Change to Western Water Resources (April 25, 2011)
http://www.doi.gov/news/pressreleases/Interior-Releases-Report-Highlighting-Impacts-of-Climate-Change-to-Western-Water-Resources.cfm


http://coyotegulch.wordpress.com/2011/04/25/interior-releases-report-highlighting-impacts-of-climate-change-to-western-water-resources/

Interior Releases Report Highlighting Impacts of Climate Change to Western Water Resources

April 25, 2011

Here’s the release from the U.S. Department of Interior:

Secretary of the Interior Ken Salazar today released a report that assesses climate change risks and how these risks could impact water operations, hydropower, flood control, and fish and wildlife in the western United States. The report to Congress, prepared by Interior’s Bureau of Reclamation, represents the first consistent and coordinated assessment of risks to future water supplies across eight major Reclamation river basins, including the Colorado, Rio Grande and Missouri river basins.

“Water is the lifeblood of our communities, rural and urban economies, and our environment,” said Secretary Salazar, “and small changes in water supplies or the timing of precipitation can have a big impact on all of us. This report provides the foundation for understanding the long-term impacts of climate change on Western water supplies and will help us identify and implement appropriate mitigation and adaptation strategies for sustainable water resource management.”

The report, which responds to requirements under the SECURE Water Act of 2009, shows several increased risks to western United States water resources during the 21st century. Specific projections include:

The report notes that projected changes in temperature and precipitation are likely to impact the timing and quantity of stream flows in all western basins, which could impact water available to farms and cities, hydropower generation, fish and wildlife, and other uses such as recreation.

“Impacts to water are on the leading edge of global climate change, and these changes pose a significant challenge and risk to adequate water supplies, which are critical for the health, economy, and ecology of the United States,” added Reclamation Commissioner Mike Connor.

Reclamation is already working with stakeholders across the West to achieve a sustainable water strategy to meet our nation’s water needs. Through the WaterSMART Basin Studies Program, Reclamation is developing and evaluating options for meeting future water demands in river basins where water supply and demand imbalances exist or are projected.

Reclamation is also continuing to implement actions to mitigate and adapt to changing climate. For example, at Hoover Dam, new wide head range turbines are being installed that will allow more efficient power generation over a wider range of lake levels than existing turbines. In addition, through the WaterSMART program, Reclamation continues to work with water users across the West to implement conservation and recycling measures and promote the efficient use of finite water resources. The Department of the Interior has also established Landscape Conservation Cooperatives and Climate Science Centers to help assess vulnerabilities to the natural and cultural resources management by the Department, and spearhead activities to adapt to the stresses of climate change.

“The WaterSMART program provides a strong foundation for the Department’s efforts to improve water conservation and help water-resource managers make sound decisions about water use,” said Assistant Secretary of the Interior for Water and Science, Anne Castle. “As climate change adds to the challenges we face in managing our water supply, meaningful engagement between the River Basin states and the Department of the Interior will continue to be essential.”

To develop the report, Reclamation used original research and a literature synthesis of existing peer-reviewed studies. Projections of future temperature and precipitation are based on multiple climate models and various projections of future greenhouse gas emissions, technological advancements, and global population estimates. Reclamation will develop future reports to Congress under the authorities of the SECURE Water Act that will build upon the level of information currently available and the rapidly developing science to address how changes in supply and demands will impact water management.

The Bureau of Reclamation is the largest wholesaler of water in the country, providing water to more than 31 million people and to one out of five Western farmers for irrigation of more than 10 million acres of farmland. Reclamation is also the second largest producer of hydroelectric power in the western United States with 58 power plants generating nearly a billion dollars in power revenues and producing enough electricity to serve 3.5 million homes.

The SECURE Water Act Report, with fact sheets highlighting climate challenges and impacts in the eight western river basins, is available online at http://www.usbr.gov/climate/.

More information about Reclamation’s WaterSMART program is available at http://www.usbr.gov/WaterSMART/.

More coverage from [Matthew Daly] writing for the Associated Press. From the article:

A report released Monday by the Interior Department said annual flows in three prominent river basins — the Colorado, Rio Grande and San Joaquin — could decline by as much 8 percent to 14 percent over the next four decades. The three rivers provide water to eight states, from Wyoming to Texas and California, as well as to parts of Mexico.

The declining water supply comes as the West and Southwest, already among the fastest-growing parts of the country, continue to gain population.

Interior Secretary Ken Salazar called water the region’s “lifeblood” and said small changes in snowpack and rainfall levels could have a major effect on tens of millions of people.

The report will help officials understand the long-term effects of climate change on Western water supplies, Salazar said, and will be the foundation for efforts to develop strategies for sustainable water resource management.

More coverage from the Huffington Post. From the article:

Meant to assess the risks of climate change, the report noted that fluctuations in temperature and precipitation are expected to cause significant changes in the future. Among the projections are temperature increases between 5 and 7 degrees Fahrenheit, and a decrease in snowpack. [Department of Interior Secretary Ken Salazar] said the report is meant to provide the starting blocks for strategies geared toward sustainable water resource management.

More coverage from Amy Joi O’Donoghue writing for the Deseret News. From the article:

…warmer conditions may result in more stresses to fisheries and specific aquatic species and facilitate an acceleration in the growth of non-native or invasive species. Such warming would also pose substantial risks to farmers because reservoirs would be subject to “significant” evaporation, decreasing water supplies to farm fields and pasture lands…

Salazar said the water report will serve as a blueprint for Colorado River water users on steps that need to be taken in light of changing climates and increased demands.

More coverage from The Pueblo Chieftain (Chris Woodka):

The report consolidates previous studies on Western water in eight major basins, including the Colorado River, Rio Grande and Missouri River basins that affect Colorado. The Arkansas River basin was not included. The report does not provide solutions to future water woes, but lays a foundation to build on, Salazar said. “This report provides the foundation for understanding the long-term impacts of climate change on Western water supplies and will help us identify and implement appropriate mitigation and adaptation strategies for sustainable water resource management,” he said…

Colorado water groups are struggling with how much more water can be developed under the Colorado River Compact, with estimates ranging from none to 900,000 acre-feet. Climate change throws in curves both on the demand side — growing seasons will be longer — and the supply side of the equation. For the South Platte, which flows into the Missouri River, projections show a 10 to 12 percent drop in river flows, despite an overall increase in moisture throughout the larger Missouri watershed. The South Platte is the most densely populated region within the watershed, particularly in the Denver metro area, although it is relatively close to the headwaters in Colorado.

The good news for the Colorado River basin is that water storage projects have been designed to deal with the historically wide variability of flows. The Colorado River has a higher proportion of storage to flows than other rivers included in the study.

More Reclamation coverage here.


http://www.google.com/hostednews/ap/article/ALeqM5j3aTZ_tQ7edI7zIJQAf4WmBTbA4g?docId=1cbb702053b84453bee806e5e281ff13

Climate change worsens Western water woes

Matthew Daly
Associated Press
2011 April 26

This July 2009 picture shows markings on the shoreline of Lake Mead indicating the
water level has dropped considerably. The Colorado River, which forms Lake Mead
behind the Hoover Dam, is among the rivers studied to determine the impact of
climate change on water supplies in the Western U.S.

WASHINGTON (AP) — Climate change is likely to diminish already scarce water supplies in the Western United States, exacerbating problems for millions of water users in the West, according to a new government report.

A report released Monday by the Interior Department said annual flows in three prominent river basins — the Colorado, Rio Grande and San Joaquin — could decline by as much 8 percent to 14 percent over the next four decades. The three rivers provide water to eight states, from Wyoming to Texas and California, as well as to parts of Mexico.

The declining water supply comes as the West and Southwest, already among the fastest-growing parts of the country, continue to gain population.

Interior Secretary Ken Salazar called water the region's "lifeblood" and said small changes in snowpack and rainfall levels could have a major effect on tens of millions of people.

The report will help officials understand the long-term effects of climate change on Western water supplies, Salazar said, and will be the foundation for efforts to develop strategies for sustainable water resource management.

The report notes that projected changes in temperature and precipitation are likely to alter the timing and quantity of stream flows in all Western river basins, with increased flooding possible in the winter due to early snowmelt and water shortages in the summer due to reductions in spring and summer runoffs. Changes in climate could affect water supplies to a range of users, from farms and cities to hydropower plants, fish, wildlife and recreation, the report said.

Western states are growing faster than the rest of the country, with some of the fastest growth occurring in the driest areas, such as Nevada, Arizona and Texas.

"Impacts to water are on the leading edge of global climate change," said Mike Connor, commissioner of the Bureau of Reclamation, an Interior Department agency that provides water to more than 31 million people in 17 Western states and power to 3.5 million homes.

The report "affirms the urgency of the planning we are engaged in," Connor said at a news conference Monday. "We need to take actions now to plan" for changes that are likely to occur over the next several decades.

The report addresses the expected impact of climate change on eight major rivers basins in the central and Western United States. Besides the Colorado, Rio Grande and San Joaquin, the report also looks at the Columbia, Klamath and Sacramento rivers on the West Coast; the Missouri River Basin in the Northwest and Great Plains; and the Truckee River Basin in California and Nevada.

All eight basins should see an increase in temperature of about 5 degrees (-15 Celsius) to 7 degrees (-13.89 Celsius) Fahrenheit by the end of the century, the report says. Four basins will see an increase in overall precipitation by 2050: the Upper Colorado, Columbia, Missouri and Sacramento, while four will see a decrease: the Lower Colorado, Rio Grande, San Joaquin and Truckee.

Reductions in spring and summer runoffs could lead to a drop in water supply in 6 of the 8 basins, the report said.

Due to early snowmelt and relatively higher winter rains from warmer conditions, all but the Colorado basin could become more vulnerable to floods, the report said.

Aiguo Dai, a climate scientist with the National Center for Atmospheric Research in Boulder, Colo., said the report echoes predictions he and other researchers have made that climate change would reduce stream flow rates in Western U.S. rivers. But he said computer models used to assess global trends would not be helpful for small river basins such as the Klamath or Upper Rio Grande.

Even regional models that take local topography into account "still contain large uncertainties," Dai said.

Sen. Jeff Bingaman said the report did "a solid job" cataloguing Interior's efforts to respond to climate change. Bingaman, chairman of the Senate Energy and Natural Resources Committee, sponsored a 2009 law that aims to improve water management in the West and increase analysis of water-related data. The report released Monday was prepared in response to the Secure Water Act.

"Faced with forecasts of decreased stream flows and increased temperatures, it's more important than ever for communities to actively plan for changing conditions," Bingaman said. "In arid environments like New Mexico, every drop counts, and conservation and efficient water use are essential."

Weather experts said Monday an extreme drought that has gripped parts of nine states is expected to drag on for several months or intensify.

Portions of Texas and a small part of eastern Louisiana are the only parts of the nation that rank in the National Weather Service's worst drought condition category. The rest of Texas and Louisiana also are very parched, as are parts of Arizona, New Mexico, Colorado, Kansas, Oklahoma, Arkansas and Florida.

Associated Press writer John Flesher in Traverse City, Michigan, contributed to this report.


Texas Citizens for Science
Last updated: 2011 April 28