Bayside Groundwater Project

Groundwater can provide water during prolonged drought

Groundwater can provide water during prolonged drought

Water for future droughts

The Bayside Groundwater Project is one of several water supply projects that will help protect EBMUD's 1.4 million customers against severe water rationing in the event of a prolonged drought.

The Bayside Groundwater aquifer beneath San Leandro and San Lorenzo has been a source of local drinking water since the early 1900's. With proper management, it can be a reliable source of local water available during a prolonged drought.

The Bayside project will use this natural storage basin by adding water to the aquifer in wet years. During dry years or drought, water will be extracted, treated and distributed to customers along with our existing supplies.

Groundwater storage, in addition to conservation, recycling, supplemental supplies from our Freeport Regional Water near Sacramento, and desalination could provide a modest amount of locally available water to help reduce the need for rationing during dry years.

Project description

The Bayside Groundwater Project began with completion of environmental review, Board approval, planning and construction. Testing was completed at the end of the first year of operation of the Phase 1 facility. This facility can store 1 million gallons of water during wet years and deliver, during drought, 1 million gallons a day (mgd) of water in dry years. The project is designed to inject excess drinking water into underground sand layers through a well during wet years for later recovery and use during a drought. All extracted water would be treated and tested to meet state and federal drinking water requirements. EBMUD has continued to partner with the U.S. Geological Survey throughout the course of the Bayside Project to ensure that the project is geologically sound.

Planning began in 2001; the Environmental Impact Report was approved by the EBMUD Board of Directors in November 2005; and the project's construction was completed in 2009.


After successfully operating the project for some time, EBMUD will consider a larger project in the area that would have a storage capacity of 2 to 10 mgd, providing even greater drought protection. The larger project would first be subjected to the same environmental and public review as the first project, and EBMUD will review results of the groundwater monitoring system and "Extensometer", which measures minute changes in ground surface elevation.

The Bayside Groundwater Project is but one of many ways EBMUD explores bringing greater water supply reliability to the District's ratepayers during drought, emergency, or for everyday needs.

With all the rain in 2017, EBMUD was able to test-inject potable water into the groundwater aquifer in February 2017. All indications are this first 5-day injection test was a success. EBMUD has no plans to extract or use the water for consumption at this time.


Alice Towey, Senior Civil Engineer for Regional Projects
Phone: 510-287-1105

Emergencies or after-hours, call EBMUD at 866-403-2683.