From the air, scientists map ‘fast paths’ for recharging California’s groundwater with hydropower
California has more than twice as many miles of rivers, streams, and groundwater as the United Kingdom. But not all of it is clean, and experts now say that nearly 70,000 acres of wells have been drilled in the last decade alone in hopes of tapping that groundwater supply, which is critical to the state’s agriculture and water management.
“We have seen some of the most dramatic development in this type of groundwater recharge in the last 15 years in California,” said Susan Kegley, the chief of the groundwater division for the California Department of Water Resources.
The state’s groundwater recharge program started in the 1980s when the California Department of Water Resources began a pilot project to recharge groundwater with hydropower from three hydroelectric plants located in Northern California.
“Now, we’ve made tremendous advances in recharge,” Kegley said. “The hydropower plants are producing about a fifth to a quarter of their power now, and their reservoirs are filling up.”
For the past 15 years, the California Department of Water Resources has worked with its hydropower suppliers to develop an efficient way to recharge their reservoirs and bring those fields back into production.
“This is really a watershed moment for California in bringing water from a state that is so dependent.
“These plants are dependent on groundwater. There’s not enough fresh water, and these are the only places in California where there’s a plentiful source of water,” he said. “If you look at the power requirements for the hydroelectric plants, it makes a lot of sense to bring that water in to replenish the lakes, to recharge the aquifers, and reduce the amount of water that is pumping through the turbines and out to the reservoirs.”
The hydropower industry started to feel the benefit of the efforts in the 1990s, when a new drought situation in California led to the state depleting its aquifers. The drought was so severe that it changed the state’s water policy and made it more difficult to implement the law, the California Water Code.
“We had more hydroelectric plants now, and the demand for more water was greater,” K