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Frequently Asked Questions

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Q. What is backflow and why should I care?

Backflow is the undesirable reversal of flow of water or other substances through a cross-connection into the public water system or consumer's potable water system. Contaminants/pollutants from a premise can enter a potable water system that unexpectedly loses pressure due to back-siphoning or back-pressure if unprotected by a backflow prevention assembly. Backflow assemblies keep these contaminants from being drawn into the public drinking water under such conditions by preventing the reversal of flow. This aids in keeping the drinking water safe.

Q. What is the law pertaining to cross-connection control and backflow testing?

For information on the laws and requirements in Washington State as it pertains to cross-connection control and backflow prevention, please visit the Washington State Legislature website, or the Washington State Department of Health website. 

Q. I got a letter from my water company saying that my water is going to be shut off. What do I do?

Simply book an appointment with us to test your backflow assembly. Ensure to let us know that you received a shut-off notice or that your water has been shut off due to not having your backflow assembly tested. We will contact your water company for you to inform them you have an appointment scheduled with us to test your backflow assembly. In MOST cases your service will be returned and/or an extension will be granted to you, pending the results of your backflow assembly test report. 

Q. How much does it cost to get my backflow assembly tested?

We charge $55 per test of each backflow assembly. For those residence that require a fire system assembly test and a domestic irrigation assembly test, the price is $100 total for testing of both assemblies. For residential assemblies that fail, if the assembly can be cleaned to make it pass, the customer will incur no additional fees. If parts are required for repair, a repair fee will be charged, but no work that requires parts will be conducted without prior approval of the customer. WE DO NOT REPLACE ENTIRE BACKFLOW ASSEMBLIES.

Q. Why is it important that backflow assemblies get tested?

Parts within backflow assemblies, like anything mechanical, are subject to fatigue, fouling, and failure. Backflow assemblies are required to perform their function above a specific differential pressure. When the internal parts wear or become fouled, they no longer operate as efficiently and protection then becomes compromised.

Q. What are you testing exactly?

Differential pressure across each check valve in the assembly is measured with a specially designed differential pressure test kit in a simulated loss of pressure condition. This is to ensure that the valves will operate as required during an actual backflow condition. On a reduced pressure assembly the relief valve is tested for set-point and functionality as well. The location, size, line pressure, air inlet opening set-point (vacuum breakers), make, model, serial number, and the operability/condition of parts are some of the other things that are inspected during the testing process. For requirements on backflow assembly test report contents please visit the Washington State Legislature website. 

Q. What if my backflow assembly fails the test?

Occasionally, backflow assemblies will fail the annual test. This can be for a number of reasons: fatigued springs, fouled/damaged discs or seats, cracked valve body, inoperable shut off valves, etc. Typically the valve only requires disassembly and cleaning if it fails the test. We do not charge additional fees for residential assemblies that only require a cleaning to pass. Sometimes valve internals are too far damaged and need to be replaced. If the entire backflow assembly requires replacement, or internals for larger commercial backflow assemblies require replacement, you may be referred to a landscaper/plumber. We only replace backflow assembly internals, where required, and do not replace entire assemblies.

Q. How often does my backflow valve need to be tested?

Washington State requires that all installed backflow assemblies be tested annually.

Any other questions, comments, or concerns please don't hesitate to contact us at or just give us a call at 509-630-0456

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