Backflow Prevention — City of Elgin

City issues reminder on water backflow prevention
Prevention of water ‘backflow’ is important in Elgin and other community water systems. Nebraska Rural Water Association states that cross connections are the most common sources of drinking water contamination. A cross connection occurs whenever there is a physical connection between sources of contamination and the public during water supply. Contamination sources can include hazardous as well as non-hazardous materials. Hazardous materials could include raw sewage or the corrosion control chemicals used by boilers. Non-hazardous substances would include edible materials such as milk or orange juice. Every house contains several cross connection sources, such as sinks, bathtubs or toilets, where there is a physical connection between the sewer system and water system. Current plumbing codes require these devices to be protected by built-in air gaps, but some older houses may still have old wash basins or bathtubs where the faucets are below the overflow level of the fixtures. These are considered unprotected cross connections. Examples of permanent cross connections are the fill line of a boiler used to heat a home or building, water softeners and other home water treatment systems. These are usually piped right into the water system in the house, and often there is no protection included in the installation. The drain line for water softeners is often plumbed directly into the sewer line of the home, which could result in raw sewage being siphoned back into the water pipes. This problem also can occur in the case of built-in swimming pools, hot tubs and underground lawn sprinkler systems. Garden hoses are the most common unprotected cross connection. There are various situations where a garden hose might be submerged in a hazardous material, such as when the hose is used to spray pesticides, herbicides or fertilizer. To protect against cross connections, home owners are advised to thread simple backflow preventer valves into their outdoor spigots. Other types of backflow preventers can be placed on other possible sources of cross connection.
Publish: May 23, 2012