Within a few weeks, lawns and gardens will need a little help from the hose to stay green and lush, but it’s critical to have your irrigation system’s backflow prevention device tested before turning it on for the season.
“Not every home has a backflow prevention device,” said Gary St. John, water quality specialist at Clark Public Utilities. “But every irrigation, automatic lawn sprinkling system or large dedicated fire suppression system is required to have one and they’re required to be inspected and tested at least once a year.”
Fortunately, the local aquifer is healthy but it requires all of us to do our part in protecting it. That’s why one of the most important things home and property owners can do is ensure their backflow prevention devices are regularly tested and working.
Backflow happens when water is drawn back into the system rather than being pushed out. It’s rare but it does happen. It’s most likely to occur just after a significant impact to the water system — like a main break or a large firefighting effort near your connection. When backflow conditions are present, irrigation systems are the greatest threat. Without a functioning backflow blocker, those heads can draw harmful lawn and garden chemicals into the water supply.
Backflow prevention assembly testing is required by law. Clark Public Utilities recommends testing in the spring, just before the irrigation season begins. It’s quick and doesn’t cost much.
To find out if your irrigation system has a backflow prevention device look for an in-ground, green-lidded rectangular box near the water meter or close to the house. If you have one, it’ll likely be in or near there.
The utility also offers a convenient annual backflow testing program for its water customers. Every year a certified backflow assembly tester is contracted at a set rate to test every participant’s backflow device. To participate, please email automatictesting@clarkpud.com or call 360-992-3000 with your name, addresses, and phone number, our staff will do the rest and register you for the program. Clark Public Utilities water customers with a noted device receive a letter annually with instructions on how to have your device tested.
“We can only check backflow status for our water service customers,” St. John said. “Other folks should check with their specific water provider.”
A list of some backflow assembly testers can be found on the Clark Public Utilities website. It’s not a recommendation or warranty — but it can be a good place to start looking for a contractor.
No irrigation system at your home, no problem — probably. Most residential and commercial plumbing fixtures have air gaps that stop backflow. Many lawn sprinkler systems are equipped with atmospheric vacuum breakers, or AVBs, that do the same.
The one place where it might happen is at a home built before the 1990s without vacuum breaker-equipped hose spigots. Replacing those will eliminate the risk. But if that’s not an option, the hose should never be submerged after it’s been shut off.
Energy Adviser is written by Clark Public Utilities. Send questions to ecod@clarkpud.com or to Energy Adviser, c/o Clark Public Utilities, P.O. Box 8900, Vancouver, WA 98688.