Silicon Valley ​Ground Water ​Back to Pre ​Drought Levels

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Silicon Valley ​Ground Water ​Back to Pre ​Drought Levels

Santa Clara County’s groundwater fell by up to 60 feet during the state’s recent historic drought due to heavy pumping, but now the vast underground basins have filled back up to the levels where they were before the drought started in 2011.

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Image: California Santa Clara, Source: Wikimedia Commons, Author: Tomwsulcer

This is a welcome trend that experts say was driven by heavy winter rains and strict water conservation rules during the drought that eased the need for pumping.

Monitoring wells run by the Santa Clara Valley Water District first picked up the recovery. And now a new scientific paper published Monday further verifies it.

“People did an amazing job at conserving water during the drought. The entire aquifer recovered,” said Estelle Chaussard, an assistant professor of geology at the University of Buffalo who led the study.

Chaussard analyzed data from four Italian satellites, which measured tiny changes in the surface levels of the ground in Santa Clara County during California’s five-year drought. She found that as groundwater levels plummeted during 2013 and 2014, the ground itself fell as the amount of water underneath it was depleted, a phenomenon known as subsidence.

From 2011 to the summer of 2014, for example, an area just north of Happy Hollow Zoo near downtown San Jose saw a 2-inch drop in the ground level, as the ground dried out like a sponge sitting in the sun.

Monitoring wells in the same area showed that the groundwater table fell by at least 60 feet during that time. Similar drops occurred in the Campbell and San Martin areas, and drops of 12 to 19 feet happened in the water table under Sunnyvale and South San Jose’s Coyote Valley.

Read full article: The Mercury News

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