Once water enters your irrigation sys- tem it can become contaminated with lawn chemicals and bacteria. Your irri- gation system is required to have ade- quate backflow protection. If you do not, blowing out the system can push this contaminated water back into your home’s water supply and/or the public water system. All systems that contain pumps or injectors for lawn chemicals are considered a high risk and should be equipped with a Reduced Pressure Back- flow Assembly (RPBA). If the system does not have pumps or injectors it is considered a moderate risk and requires a Double Check Valve Assembly (DCVA) or a Pressure Breaker Vacuum Assembly (PBVA). However if you plan to use an air compressor on your irrigation sys- tem, a PBVA will not provide adequate protection. Please read the next section on Cross Connection Control for more.
For more information or to learn if your system has backflow protec- tion contact the District at 922- 5443 or visit these websites:
Spokane Regional Cross Connection Control Chapter
Washington State Department of Health—Office of Drinking Water
Spokane Aquifer Joint Board