Common Cross-Connections

Your Role as a Water Customer

By taking steps to control cross connections and prevent the possibility of backflow at your home, you will help to protect the public water supply and ensure that your family continues to enjoy safe drinking water.  Garden hoses and irrigation systems are common concerns, but there are other common residential sources of cross connections, too.

Garden Hoses and Backflow

The garden hose is the most common cross connection.  Each of these common uses of a garden hose sets up a cross connection:

• forcing it into a clogged gutter, downspout, or sewer pipe to flush out the clog
• connecting it directly to a hose-end sprayer to apply pesticide or fertilizer to your yard
• connecting it to a soap-and-brush attachment to wash your car, boat, or siding
• letting the end of the hose lie in a puddle or pool of water on the ground

No doubt you can think of other examples.  In each of these cases, if backflow happens, your household's water lines could be contaminated. Depending on how long the backflow event lasts, the contamination could spread to the public drinking water system.

Fortunately, there are two inexpensive ways to solve this problem:

• Make sure that the end of your garden hose is never submerged in or connected to a nonpotable substance.  This solution is free, but not higly reliable. Can you always be this careful?
• Install a hose bibb vacuum breaker on each of your outside faucets.  These inexpensive devices are designed to allow water to flow in only one direction.  You can find them at most home supply stores and through plumbing suppliers.  Before you use a hose-end sprayer, you should first install a hose bibb vacuum breaker at the faucet.