By Roger Bales, University of California, Merced and Brandi McKuin, University of California, Santa Cruz
Climate change and water scarcity are front and center in the western U.S. The region’s climate is warming, a severe multi-year drought is underway and groundwater supplies are being overpumped in many locations.
Western states are pursuing many strategies to adapt to these stresses and prepare for the future. These include measures to promote renewable energy development, conserve water, and manage natural and working lands more sustainably.
As engineers working on climate-smart solutions, we’ve found an easy win-win for both water and climate in California with what we call the “solar canal solution.” About 4,000 miles of canals transport water to some 35 million Californians and 5.7 million acres of farmland across the state. Covering these canals with solar panels would reduce evaporation of precious water – one of California’s most critical resources – and help meet the state’s renewable energy goals, while also saving money.
Conserving water and land
California is prone to drought, and water is a constant concern. Now, the changing climate is bringing hotter, drier weather.
Severe droughts over the past 10 to 30 years dried up wells, caused officials to implement water restrictions and fueled massive wildfires. As of mid-April 2021, the entire state was officially experiencing drought conditions.
At the same time, California has ambitious conservation goals. The state has a mandate to reduce groundwater pumping while maintaining reliable supplies to farms, cities, wildlife and ecosystems. As part of a broad climate change initiative, in October 2020 Gov. Gavin Newsom directed the California Natural Resources Agency to spearhead efforts to conserve 30% of land and coastal waters by 2030.
Most of California’s rain and snow falls north of Sacramento during the winter, while 80% of its water use occurs in Southern California, mostly in summer. That’s why