OCWD Board of Directors

Cathy Green
First Vice President
Denis R. Bilodeau, P.E.
Second Vice President
Philip L. Anthony
Jordan Brandman
Shawn Dewane
Jan M. Flory, ESQ.
Dina L. Nguyen, ESQ.
Roman Reyna
Stephen R. Sheldon
Roger C. Yoh, P.E.
General Manager
Michael R. Markus
P.E., D.WRE.

Basin Storage Update

The volume of the Orange County Groundwater Basin is quite large, but only the upper portion is available for normal use. Although the basin's aquifers contain more water than many lakes and surface reservoirs, these aquifers can't be fully accessed as they are hydraulically connected to the ocean. To draw the basin down too far would create or worsen at least three problems: (1) Seawater would move inland, threatening to impact drinking water wells with salty water; (2) Decreased groundwater levels would increase the risk of irreversible land subsidence that could damage buildings, bridges, pipelines, and other structures; and (3) Increasing numbers of drinking water wells could be unable to pump due to water levels dropping below the wells' intakes.

Over decades of experience, OCWD determined the safe operating range of its aquifer to be from a completely full condition to overdrafted by 500,000 acre-feet. That is about 75 percent of the water volume stored in Lake Havasu when full or nearly two years' worth of groundwater extractions.

Recently, because of drought conditions, the basin overdraft has increased as less water from Mother Nature has been available to recharge the groundwater basin. OCWD has worked to maximize how much recycled water from the Groundwater Replenishment System could be produced and recharged into the basin. The District was also purchasing large quantities of imported water for basin recharge until these supplies were recently curtailed.

The overdraft that we are experiencing is not yet worrisome and is within the groundwater basin's normal operating range. It is the wonderful benefit of having access to, yet carefully using, such a vast underground reservoir during times of drought. However, the situation is becoming a concern as we now measure 381,000 acre feet of overdraft, which means the basin is about 80 percent empty.

If it does not rain soon, recent water conservation measures by the general public might not be enough and groundwater extractions may be subject to further constraints. OCWD will continue to explore diversification of its water portfolio to be prepared for California's cyclical droughts.