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Cross Connection in Home Plumbing

A plumbing cross connection is a physical or potential connection between a non potable water source and a potable water supply. In an event of a backflow, non potable water will re-enter and mix with the potable water supply through an unprotected cross connection. Backflows are usually triggered by a sudden loss of pressure in the supply system. Inadequately protected cross connections can be responsible for the contamination of the drinking water supply and the spread of disease.

Prevent cross connections in the home. Submit the form on your right to receive multiple plumbing estimates on cross connection services by local plumbers.

Potential Cross Connections in the Home

1. When faucet outlets or spouts and spray hoses are below the flood rims of sinks and bathtubs. Always leave an air gap between the spout and water line when filling sinks and tubs to prevent a potential cross connection. Otherwise stagnant water filling sinks and tubs may be siphoned back into the supply line during loss of pressure.

2. Any toilet flushes waste by means of water that leaves the supply system and enters the toilet tank where it is stored, and often treated with cleansing detergents. To keep tank water from re-entering the drinking water supply during loss of pressure the float valve or anti-siphon ballcock (see toilet) needs to be positioned above the water level in the tank.

3. The garden hose is the number one potential cross connection in the home as it is attached on one end to an outside faucet while the other end is connected to an aspirator containing fertilizer, antisecticides and other chemicals used in the garden. Hose bibb vacuum breakers installed on all spouts in your home will prevent contaminates from being drawn into the drinking water supply during loss of pressure.

4. Water that collects around the head of the sprinkler often contains lawn and pesticide chemicals. Improperly installed or poorly maintained sprinklers can permit contaminates to re-enter the home's drinking water supply during loss of pressure. A professional lawn irrigation contractor or a licensed plumber can help you eliminate your sprinkler system as a potential cross connection by installing an atmospheric vacuum breaker (AVB), pressure vacuum breaker (PCB) or a reduced pressure principal assembly (PR).

5. Installation of a dual check with atmospheric vent in a water heater prevents the possibility that stagnant or chemically treated water will re-circulate back into the water supply during loss of pressure.

Need to install cross connection preventors? Submit the adjacent form to receive multiple plumbing quotes.