One of Santa Cruz County’s largest water sources is ‘critically overdrafted’; fixes are on the way

A worker finishes installing the Pure Water Soquel purification facility’s start-and-stop unit. (Kevin Painchaud / Lookout Santa Cruz)

More than 50,000 residents of Santa Cruz County are reliant on a single water source: the dwindling Mid-County Groundwater Basin, which the state deemed “critically overdrafted” nearly a decade ago. Now local agencies are embarking on efforts to boost the ability of the basin to capture more rain during the wet months along with an ambitious plan to replenish the basin’s drinking water supply with recycled wastewater.

A number of agencies — including Soquel Creek Water District, the City of Santa Cruz Water Department, the Central Water District — and several thousand private well owners share the underground basin, a reserve made up of a group of linked aquifers, in an area that encompasses the Eastside of Santa Cruz, Live Oak, Soquel, Aptos and Capitola. That’s a lot of sources for one basin to supply.

That, coupled with California’s extended periods of drought, led the state to designate the basin as “critically overdrafted” in 2014. That means more water is being pumped out of the basin than it can naturally replenish via rainfall. Out of 500 total basins in California, Mid-County is one of 21 the state has deemed critically overdrafted, and the state has mandated that local bodies form “groundwater sustainability agencies” to find a solution.

Shortage of available water isn’t the only problem. Pumping too much groundwater from a basin can lower water levels enough to draw seawater inland, contaminating groundwater with salt. This phenomenon is called seawater intrusion, and it has been observed at several locations of the Mid-County Groundwater Basin as far back as the 1980s.

The local groundwater sustainability agency — made up of the three districts that share the basin along with the County of Santa Cruz — was the first to have its basin plan approved by the state. Now, two projects are well underway: Pure Water Soquel and the City of Santa Cruz’s Aquifer Storage and Recovery (ASR) project seek to address the seawater intrusion problem in the Mid-County Groundwater Basin while also maintaining a stable, reliable water supply for the county’s still-growing population.

These projects aim to provide a larger supply of water for county customers, utilize water that would otherwise typically be released into the ocean, and ensure that local water agencies will not rely as much on surface water sources, like the San Lorenzo River and Loch Lomond Reservoir, to supply residents with water. That’s especially vital in an area […]

Full article: lookout.co