Salinas Valley – East Side Aquifer

Statistics

Basin Name

Basin Number

3-004.02

SGMA Basin Priority

High

Critically Overdrafted

Status

Subject to SGMA

DWR Region & POC

South Central Regional Office
Benjamin Gooding (559) 230-3359 Benjamin.Gooding@water.ca.gov

Number of Wells

808

Hydrologic Region Name

Central Coast Hydrologic Region

Counties

Monterey

Adjacent Basins

Salinas Valley Forebay Aquifer 3-004.04, Salinas Valley 140/400 Foot Aquifer 3-004.01, Salinas Valley - Langley Area 3-004.09,

At-A-Glance

Located in California’s Central Coast hydrologic region, the Salinas Valley – East Side Aquifer is 57,474 acres in size. This High priority basin is home to an estimated 128,550 people (2010 value), which have been at a rate of 17.84. Salinas Valley – East Side Aquifer is a(n) basin with approximately 808 wells, of which approximately 49 are water supply wells. Groundwater accounts for approximately 100 percent of the basin’s water supply.

Source: CA DWR

2003: Bulletin 118 basin description

2018: Draft prioritization comments:

Groundwater level decline: Longterm hydrographs show decline. “In most of the subareas, were seeing historic lows, said MCWRA senior hydrologist Howard Franklin, adding that he expects new data to show that underground seawater intrusion into the basin, which slowed in recent years, has restarted its march down the valley. Santa Cruz Sentinel, 3/5/15
Seawater intrusion: This began in the Salinas Valley by the 1930s and now extends more than five miles inland. The Monterey County Flood Control and Water Conservation District built Nacimiento Dam in 1957 and an Antonio Dam in 1965 to provide flood control and to accelerate groundwater recharge to mitigate seawater intrusion. In April 1998, the Monterey County Water Recycling Projects started delivering recycled water for irrigation in lieu of groundwater pumping, effectively slowing the seawater intrusion rate (MCWRA, 2006). Central Coast Groundwater: Seawater Intrusion and other Issues, California Water Foundation, August 4, 2014. 2)The Salinas Valley Water Project is currently being implemented by the Monterey County Water Resources Agency to mitigate groundwater overdraft and seawater intrusion. The project includes mitigation measures such as construction or retrofit of recharge dams, protection of recharge areas, and injection of recycled water into the impacted aquifers.

2018 Final Basin Prioritization: Basin status remains unchanged at high priority.