(CN) - Rising sea levels and soaring temperatures caused by climate change could exacerbate California's water shortage and increase stress on its most important natural resources, according to a federal report released Tuesday.
Climate change could raise average temperatures in the Sierra Nevada mountain range by more than 5 degrees by the late 21st century and sea water is likely to intrude further into California's vital freshwater holding tank - the Sacramento-San Joaquin Delta - according to predictions by the Bureau of Reclamation. The study says global warming could cause a median sea level rise of 36 inches and flood the delta with salt water.
The report studied the Sacramento and San Joaquin river basins and concluded that increased temperatures will melt the state's snowpack earlier and diminish the state's capacity to store water in its network of reservoirs due to excess runoff.
According to the report, the snowmelt will fill reservoirs earlier in the year and that evaporation would increase with the higher temperatures. In order to combat climate change, the study suggests improved conservation and policies for groundwater and surface water to meet the state's increasing water needs.
"These basins are at the center of discussions about the availability of water in California, not only for agriculture, but for municipal and environmental needs as well," Reclamation Commissioner Estevan Lopez said in a statement. "Because of the collaborative efforts put forth in this basin study, we now have more information on how climate change will impact this region and a better understanding of what will be needed to ensure a sustainable water supply for today and for the future."
The report comes as lawmakers grapple with ways to prevent water from recent El Nino storms from escaping to the Pacific Ocean unused. The debate between providing water for the largest estuary west of the Mississippi River and funneling it south has gained Congress' attention.
Sen. Dianne Feinstein, a Democrat, last week called on federal and state agencies to ramp up pumping through the delta and increase deliveries south to Central Valley farmers and Southern California cities.
Feinstein and California farmers want the bureau to be more flexible with its water policies in light of recent storms that quickly filled up the state's reservoirs. As of March 6, almost three million acre-feet of water passed through the delta and just 22 percent of it was captured, Feinstein's office claims.
"Pumping less water even though river flows more than doubled means 180,000 to 200,000 acre-feet of water was allowed to flow out to the sea instead of being captured and stored," Feinstein said in a statement.
The state's drought-riddled reservoirs have recovered thanks to the recent El Nino storms, with the latest measurements showing nearly a quarter of the state's reservoirs have above-average stores for this time of year. Major reservoirs such as Folsom Lake and Lake Shasta are above historic averages after several years of consecutive drought.
Recent measurements also have the state's growing snowpack at 92 percent of normal statewide.
Meanwhile, environmentalists contend the delta has long been overused and that a lack of fresh inflow has contributed to a massive decrease in the salmon population, a species protected under the Endangered Species Act. They argue the recent deluge is necessary to flush the delta and protect the struggling fish populations.
If nothing is done to combat future climate change, the 122-page report warns that delta water quality could be significantly damaged by sea-water intrusion and a shortage of cold water supplies from California reservoirs. Flood control, hydroelectric power production and ecological impacts would also be exaggerated by climate change.
To effectively prepare for future climate change, the bureau calls for a "multi-faceted approach that applies a wide range of strategies at local, state and regional levels."
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