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Backflow Prevention Program

The Cross-Connection Threat

Your drinking water is pushed from the district's water main into your property’s plumbing by pressure and it should only flow in one direction. Sometimes, due to pressure changes in pipes, the water can flow backwards into your water line or district water lines and could contaminate the public water supply with human waste or chemicals.

This backwards (or backflow) can occur in properties that have multiple water lines, such as those that have fire sprinklers in the house, or have a separate water line to a swimming pool. It can also happen if the outdoor irrigation system is accidentally "cross-connected" to the indoor plumbing system by someone that doesn't understand plumbing.

EOCWD_Cross-Connection Threat

The Backflow Prevention Device

To protect against this contamination, a specialized backflow preventer valve is installed at strategic locations in the plumbing system wherever there is a risk of contaminated fluids entering the water supply pipes. Because these valves use moving parts, they are often required to be inspected or tested periodically.

For many years, customers were required to annually retain a certified backflow tester to inspect and test the backflow devices, and if they passed, send the certification to us. If they didn't pass, the customer arranged the repairs and then had the unit retested and then sent the certification - this work had to be completed between February 1st and March 31st. This process was difficult for some customers and several asked if the District could help them with completing the requirements. Based upon results from a pilot program, at their December 18, 2019 Meeting, our Board decided that District staff would now perform all backflow testing.

EOCWD_Backflow Prevention Device graphic

Getting your Backflow Prevention Device tested


Your home may be equipped with a Backflow Device to prevent wastewater or other contaminants

from flowing backward into the water system. Getting it checked each year to ensure it's working

properly is essential. This protects our water supply and allows EOCWD to continue delivering safe and

healthy drinking water to customers.

Here's what you need to know:

• $29.45 one time fee billed on your water bill

• EOCWD conducts testing and processes all certificates

• Customer is responsible for device repair if needed

• No "retesting" charges

East Orange County Water District technician tests a backflow device.
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