What is a Cross-Connection?

A cross-connection is a direct or potential connection between any part of the public water supply system and a source of contamination or pollution.  The most common form of cross-connection is a garden hose, which is easily connected to the public water supply system and can be used to apply a variety of potentially dangerous substances, including chemicals and fertilizer.  Another common cross-connection is the lack of an air gap on water softeners.  This is a cross-connection because the water line is connected into the sewer drain and a backup could contaminate the water supply.  Other common cross-connections may include dishwashers, toilets, pressure washers, boilers, pools and lawn sprinkler systems.

How Does Contamination Occur?

Water normally flows in one direction, from the public water system through the customer’s cold or hot water plumbing system to a faucet or other plumbing fixture.  Under certain conditions, water can flow in the reverse direction.  This is known as backflow, and it occurs when backsiphonage or backpressure is created in a water line.

Backsiphonage may occur when there is a drop in the supply pressure of the water distribution system.  This can be caused by a water line break, water main repair, or during withdrawal from a nearby fire hydrant.  This creates a vacuum, which may pull or siphon contaminants or pollutants into the drinking water supply.

Backpressure may be created when a source of pressure, such as a pump, boiler, or other building creates a pressure greater than that supplied from the water distribution; this may force water to reverse direction.

What is a Cross-Connection Survey and How Often Will They Occur?

During a cross-connection survey, a representative of the water utility will perform a walk-through of the water system piping in the building or property, starting at the water meter and ending at the last free-flowing tap.

At minimum, Johnson Creek water personnel must survey/inspect residential units at the time of water meter installation and/or testing (every 10 years).  Commercial and industrial facilities are inspected every two years.

Questions?

Contact Aric Mindemann, Public Works Director at (920) 699-3341 for any cross-connection questions.  Cross-connection regulations are set forth by the Wisconsin Administrative Codes COMM 82 (Department of Commerce) and NR 811.09 (Department of Natural Resources) and Village Municipal Code 228-32.