The new reservoir will ensure that water supplies are available even during shutdowns of the Diemer Filtration Plant in Yorba Linda (shown above.)

The Upper Chiquita Reservoir is not being built to provide day-to-day drinking water; rather, it will only be used to help meet emergency water shortfalls, such as cutbacks of State Water Project deliveries, or breaks in regional pipelines.

Having an emergency supply is important because, while water districts in north Orange County have access to an underground aquifer that supplies them with approximately half of their water supply, south Orange County generally has no such resource and must rely upon other water sources, so we are especially vulnerable to interruptions in water deliveries.

A Real Need
Nearly all south Orange County’s water supply is purchased from the Metropolitan
Water District of Southern California (MWD), which delivers water from Northern
California via the State Water Project and from the Colorado River.

Unfortunately, due to California’s fragile water infrastructure and various legal challenges, these supply lines can be disrupted for a number of reasons. When they are, local water districts may experience temporary supply shortages. Additionally, our local water infrastructure also is vulnerable. For example, when the pipeline serving most of the South County broke in 1999, and when MWD’s Diemer Filtration Plant in Yorba Linda shut down in 2007 for maintenance, water deliveries to the South County were interrupted.

Local agencies, like those proposing the Upper Chiquita Reservoir, have an obligation to their customers to identify and develop water infrastructure, including emergency storage facilities, to protect and enhance local supply reliability.

Smart Planning for South County
If built as proposed, the Upper Chiquita Reservoir will safely store 266 million gallons of emergency drinking water for 168,000 families. These supplies will provide 200 gallons of water per day for up to one week for thousands of families during planned or unplanned disruptions of water deliveries to south Orange County.