BuRec report says higher temps, changes to runoff likely under most climate change scenarios
By Summit Voice
SUMMIT COUNTY — Water supplies in the western United States could be hit hard by projected global warming impacts, including temperature increases of 5 to 7 degrees across the region, according to the Department of Interior, which this week released a new report assessing how climate change could affect water operations, hydropower, flood control, and fish and wildlife.
The report to Congress was prepared by the Bureau of Reclamation and 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.
The report forecasts an 8 to 20 percent decrease in average annual stream flow in several river basins, including the Colorado, the Rio Grande, and the San Joaquin. Big changes in the timing and volume of spring runoff are likely to have impacts on agriculture and hydropower operations.
These changes in timing are not just speculation or projections for the future. U.S. Geological Survey measurements have already shown that peak spring runoff is coming as much as two weeks earlier in some river basins.
Other impacts include less precipitation over the southwestern and south-central regions of the country, with more precipitation over the northwestern and north-central portions of the western United States.
Significantly for water managers, the projections include a decrease for almost all of the April 1 snowpack, a standard benchmark measurement used to project river basin runoff.
“Water is the lifeblood of our communities, rural and urban economies, and our environment,” said Interior Secretary Ken Salazar. “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,” Salazar added.
“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,” said Bureau of Reclamation commissioner Mike Connor.
The Bureau of Reclamation has already taken some steps to mitigate impacts and adapt to changing climate. For example, at the 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. The Department of the Interior has also established landscape conservation cooperatives and climate science centers to help assess vulnerabilities to natural and cultural resources.
“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.”
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/
Filed under: climate and weather, Colorado, Environment, global warming, water Tagged: | climate change, Colorado River, Environment, global warming, Hoover Dam, Ken Salazar, runoff, Summit County News, United States, United States Bureau of Reclamation, United States Secretary of the Interior, water, Western United States