Cross-Connection and Eliminating Potential Hazards to the Residential Water Supply

CROSS-CONNECTIONS EXPLAINED
Your water can become contaminated if connections to your plumbing system are not properly protected. To avoid contamination, backflow preventers are required by state plumbing codes wherever there is an actual or potential hazard for a cross-connection (faucets and other plumbing fixtures). A cross-connection is an actual or potential connection between the safe drinking water (potable) supply and a source of contamination or pollution. The Wisconsin Department of Natural Resources requires all public water suppliers to maintain an ongoing cross-connection control program that involves public education, onsite inspections, and possible corrective actions, if required.

When you turn on your faucet, you expect the water to be as safe as when it left the treatment plant. However, certain hydraulic conditions left unprotected within your plumbing system may allow hazardous substances to contaminate your drinking water or even the public water supply. Water normally flows in one direction. Under certain conditions, however, water can actually flow backwards; this is known as backflow. Two situations can cause backflow. Backsiphonage may occur due to a loss of pressure in the municipal water system during a fire fighting emergency, a water main break, or system repair. This creates a siphon, which can draw water out of a sink or a bucket and back into the water system. Backpressure may be created when a source of pressure (such as a boiler) creates a pressure greater than the pressure supplied from the public water system. This may cause contaminated water to be pushed into your plumbing system at an unprotected connection.

MORE INFORMATION
To learn about measures you can take to protect your drinking water supply, see the tips shared below and visit www.hydrodesignsinc.com/wiccc.html or water.epa.gov.


TO PROTECT YOUR WATER SUPPLY...

OUTDOORS

• Don't submerge hoses in tubs, buckets, pools, sinks or ponds
• Keep the ends of hoses clear of all possible contaminants
• Don't use spray attachments without a backflow prevention device

FOR THOSE WHO "DO IT YOURSELF"

• Verify and install a simple hose bibb vacuum breaker on all threaded faucets around your home
• Don't connect waste pipes from water softeners or other treatment systems directly to the sewer or submerged drain pipe. Always be sure there is a one inch "air gap" separation

KITCHENS

• Make sure dishwashers are installed with a proper "air gap" device

BATHROOMS

• When a hand held shower fixture is hanging freely, ensure that it is at least one inch above the top of the flood level rim of your bath tub or water receptacle, that it complies with ASSE #1014 (indicated on product or packaging), and has the ASME code 112.18.1 stamped on the handle
• Look for the ASSE #1002 standard symbol on toilet tank fill valve devices and packaging
• Replace unapproved toilet tank valve products with an ASSE #1002 approved device
• Verify that the overflow tube is one inch below the critical level (CL) marking on the device