Seawater threatens Central Coast’s water supply

Posted: 12:59 pm, August 4, 2014 by Publisher Scott Brennan

Declining groundwater levels and salt water intrusion are impacting water quality

A new report released today by the Groundwater Voices Coalition says that groundwater resources in the Central Coast are seriously threatened by saltwater intrusion. Groundwater levels have declined as a result of several dry years and over-pumping, which has allowed seawater to contaminate the region’s underground water supply.

As seawater moves in, it causes severe water quality impacts, which can result in saline groundwater that is unsuitable for agricultural and community uses. Seawater intrusion also directly threatens the Central Coast’s economy, where many high-value, salt-sensitive crops, such as strawberries, are grown.

“The Central Coast area relies on groundwater for a greater percentage of its water supplies than any other region in the state,” said Lester Snow, executive director of the California Water Foundation. “As California faces one of the worst droughts in recorded history, we must consider ways to protect the Central Coast’s invaluable groundwater resource for the present and future health of its farms, cities and environment.”

The Central Coast region is geographically isolated and relies nearly exclusively on local water resources. Moreover, it cannot easily bring in new surface water that is more readily available to other areas of the state. More than 80 percent of the Central Coast region’s water supplies come from groundwater. Compare that to the rest of the state, which relies on groundwater to meet roughly 40 percent of its water demands in an average year and up to 60 percent or more during droughts such as this year.

The report, Central Coast Groundwater: Seawater Intrusion and Other Issues, was prepared by Julie Nico Martin and commissioned by the California Water Foundation to inform policy decisions about groundwater management. It studied the 80 groundwater basins in the Central Coast region. More than 40 percent of those have been ranked as either “high” or “medium” priority, according to the California Statewide Groundwater Elevation Monitoring (CASGEM) groundwater basin prioritization list.

The report highlights four areas within the Central Coast region: the Monterey and Salinas Valley area, the Paso Robles area, the Santa Barbara area and the Oxnard area. Each region has varying groundwater issues from contamination to dry wells to subsidence to saltwater intrusion depending on the basin, which the report explores in detail.

The report highlights the work that has been done to address some of the current threats to groundwater resources but finds it is not enough. With serious threats remaining, the report makes a number of recommendations to improve the effectiveness of groundwater planning to support sustainable groundwater management. The full report is available at www.groundwatervoices.com. The recommendations include:

Establish a statewide goal of sustainability
Organize and empower local groundwater agencies
Require the development and enforcement of groundwater management plans
Provide technical guidance and financial support to local agencies
Empower the state to oversee implementation

About the Groundwater Voices Coalition

The Groundwater Voices Coalition is an effort sponsored by the California Water Foundation aimed at uniting people from every corner of the state and every segment of the political spectrum to educate decision makers about the need for more effective and sustainable groundwater management.