Widening Levees Could Help Replenish California's Groundwater Supply
SACRAMENTO (CBS13) - Believe it or not, flood control could be a solution to help ease California's drought.
Scientists at UC Davis say widening some levees, or removing them all together, could recharge the state's groundwater.
During drought years, Californians are pumping out more groundwater than our system can sustain.
But UC Davis researchers say they've found a way to replenish our supply.
Drone video shot after a February storm shows the banks of the Cosumnes River overflowed with water.
"A little bit of recharge in an area that reaches the rest of the aquifer system can improve the pressures or the water levels on a regional scale," said UC Davis hydrogeology professor Dr. Graham Fogg.
Today, lush plants and birds now live in this flood plain that was once blocked off from any water by a levee.
"In most rivers in California, in the Central Valley, levees have been built right up to the banks of the river, which means when the floods come, most of the river flows just go right on through," said Fogg.
Fogg says by widening or, in this case, removing one side of the levee allows rushing flood waters to spread and then settle into the ground.
"The benefits can be quite significant," said Fogg.
But Fogg says there is one downside. If a flood plain is full of water, the land can't be used for anything else.
"In a place like Sacramento, where you have so much urbanization in the flood plain, it wouldn't be feasible," he said.
He says going forward this levee widening technique can help California weather extreme droughts, especially near farmland by storing more water underground for a not so rainy day.
"We anticipate with climate change there will be more extreme weather, both more droughts and more wet years, and we need to be able to use those wet years to store the water and the groundwater whenever we can," said Fogg.
Fogg says just one or two storms can significantly recharge groundwater in small flood plains.
Other places like Orange County have seen groundwater replenishment success with similar levee widening projects.
