26 February 2013
By Bob Berwyn Summit Voice
FRISCO — Some of the West’s biggest reservoirs could dry up completely as the region gets warmer and drier in coming decades, and major increases in storage capacity probably won’t help address regional water shortages, according to a new study authored by researchers with Colorado State University, Princeton and the U.S. Forest Service.
In the Colorado River Basin, “Lakes Powell and Mead are projected to drop to zero and only occasionally thereafter add rather small amounts of storage before emptying again,” the scientists concluded, adding that smaller upstream reservoirs might still be useful.
The report, published by the U.S. Forest Service Rocky Mountain Research Station, combined climate projections
with socio-economic scenarios of population growth and water use to determine future water supply and demand, to assess the likelihood of future water shortages region by region.
After analyzing the data, the researchers concluded that most of the Southwest, parts of California and the southern and central Great Plains will be the most vulnerable areas in the nation to water shortages during the next 60 years.
Climate change will substantially increase water demand and cause decreases in water supply in those regions of the United States, even as cities, farms and thermoelectric facilities become more efficient in their water usage.
“We were surprised to find that climate change is likely to have a much greater effect on future water demands than population growth, said Forest Service research economist Tom Brown, who led the study along with CSU’s Jorge A. Ramirez. “The combined effects of climate change on water supply and demand could lead to serious water shortages in some regions.”
Specific outcomes varied depending on exactly which climate change and population numbers were plugged into the model, but the overall results were similar. Given most accepted projections of climate change and population growth, major adaptation efforts appear inevitable, including. “groundwater mining (while supplies last), reductions in in-stream flows, water transfers, water conservation beyond the levels assumed here, alterations of reservoir operating rules and other water management agreements, population shifts, and, in selected locations, increases in water storage and diversion capacity.”
Find the study here.