Don't let your lawn irrigation system contaminate the water you drink!
Your lawn irrigation system is potentially hazardous to your drinking water.
Irrigation systems make watering lawns and gardens easier while saving time. However, weed killers, fertilizers, and other contaminants can enter the water system through backward movement of water called "backflow". This backflow can be caused by changes in the water pressure, for example, when fire fighters fight a nearby blaze or before City crews repair a broken water main. If a backflow occurs, your unprotected irrigation system could endanger the health of your household and neighborhood.
This backwards movement allows the water in your pipes to flow in the opposite direction, back through your pipes, and therefore into your drinking water supply. This situation is created by a "cross-connection." Cross-connections can occur when your lawn watering system is not protected with a backflow protection assembly.
Contaminants on your lawn may enter your sprinkler system. Sprinkler heads sit at or below ground level where animals and pets may urinate on them and drop feces, which can contain harmful bacteria. In addition, pesticides from your lawn, and bacteria in the soil can be pulled back into your home drinking water system, and could ultimately end up in the public water system.
The City of Bremerton's Water Utility requires a "double check valve assembly" for irrigation systems to prevent backflow. This assembly is simply two spring-loaded check valves in a row, with a shut-off valve on either end, and test cocks to allow the assembly to be tested for proper operation. A double check valve assembly can be installed lower than the irrigation system in an underground vault, or it can be installed in a basement to protect it from freezing. Regardless of where they are installed, they must be readily accessible for maintenance and testing. Irrigation systems without an approved backflow preventing device are in violation of state and local regulations.
ALL IRRIGATION SYSTEMS, new and existing, MUST BE EQUIPPED with an approved backflow prevention assembly. The City provides safe drinking water, please help keep it safe by ensuring your irrigation system has the proper backflow preventer.