It's been a big rain year for San Diego County, and that got a Midday Edition listener wondering about the impact on the county's reservoirs. The listener wrote in with this question:
Is SD (County) doing as much as can be done to keep the varying rain amounts in, direct the rain to reservoirs? Purpose of our reservoirs? Are any reservoirs used as sources for drinking water (to be purified)? Recreation, boating & fishing, I'm guessing are the main uses.
To answer those questions, Midday Edition spoke to Dana Friehauf, resource manager with the San Diego County Water Authority and Jeff Pasek, watershed manager, city of San Diego Public Utilities Department.
The county water authority manages the county’s water supply. There are 24 reservoirs in the county. About 10 percent of the county's water supply comes from those reservoirs, Friehauf said. Over 70 percent of the county's water comes from the Colorado River.
She said that all of the rain is increasing the elevation of the county’s reservoirs significantly. For example, at Lake Hodges near Escondido there’s been a 12-foot elevation increase and at El Capitan reservoir near Alpine there has been a 16-foot elevation increase between the end of 2018 and Feb. 25.
Friehauf said the rainfall captured in the reservoirs will allow the county to import less water.
She said the county is limited in being able to capture more rainwater.
"We really don't have anywhere else to store the water. We really don't have the large groundwater basins like they have in Orange County or LA County, where we can further capture that stormwater and let it percolate down into the groundwater basins. So, we don't really foresee any large stormwater capture projects, but what we do see is smaller efforts going on on site," Friehauf said.
She said an example of one such project is at the airport.
The Airport Authority is currently constructing a second stormwater capture system. It will be able to store 3 million gallons of rain water, said Rebecca Bloomfield, a spokeswoman for the San Diego International Airport. The existing system captures rain water that falls on the terminal 2 parking plaza. It can store 100,000 gallons of water.
Residents can also capture water on their property in rain barrels, Friehauf said.
Pasek joins Midday Edition Monday from San Vicente Reservoir to talk about how that water is treated before making its way to customers' faucets.