Cross Connection Control & Backflow Prevention

Important information on backflow prevention and identifying cross-connections to help protect your drinking water.

Read the Cross Connection Control and Backflow Prevention program here.

What is a cross-connection?

 A cross-connection is an actual or potential connection or link between the Water Authority’s potable water system or your (the consumer) water system and ANY source of non-potable liquid, solid, or gas that could contaminate the potable water supply by backflow. Backflow is the reversed flow of water (or other liquid, solid, or gas from any source) back into the potable water system by either back siphonage or back pressure.

Back siphonage is backflow caused by a negative pressure (vacuum or partial vacuum) in the potable water system. Back siphonage occurs when the system’s pressure is reduced below atmospheric pressure. The effect is similar to sipping water through a straw.
Example: Homeowner “Bob” has connected a pesticide bottle to his garden hose and starts treating the lawn. At the same time, the potable water system is being flushed, which creates a partial vacuum in the water main supplying Bob’s house. If Bob does not have an atmospheric vacuum breaker attached at his hose connection, the pesticide can be siphoned back through the hose and into the potable water system. The contaminated water can then flow directly into Bob’s home and/or other homes in Bob’s neighborhood.
Backflow by back pressure occurs when the non-potable system’s pressure exceeds the potable water system pressure. The effect is similar to blowing air through a straw to create bubbles at the other end. Back pressure can force or push an undesirable contaminant into your drinking water. Sources of backpressure may be pumps in the distribution system, boiler units, heat exchange devices, or power washing equipment.
Example:  At ACME Industry, hot and cold water feed a pump operating at 75 psi with the discharge side of the pump connected to a gun-type spray nozzle. A hose connects a chemical tank to the pump, which supplies a chemical and water mixture to the spray gun.
The pump is left on between cycles, and the pump pressure of 75 psi overcomes the city water pressure of 50 psi causing the chemical to backflow from ACME Industry and into the supply water main. A customer at a nearby mall reports a bad taste in the water which eventually leads to the discovery of the backflow condition.

How can you prevent backflow from occurring?      

Working together to protect your drinking water supply. The Bedford Regional Water Authority and all of our customers share the responsibility to help safeguard the public water supply. We are working with the Virginia Department of Health and our customers to identify potential backflow issues so that your drinking water quality is maintained at the highest possible level.                                                   
The most common cause of a cross-connection is one of the most over-looked items in the home - a garden hose. Hoses left submerged in swimming pools, landscaping ponds, or buckets or attached dispensers containing cleaning chemicals or pesticides are a cross-connection problem waiting to happen.                                                                          
Per building codes, a hose-bib vacuum breaker should be attached to all outside spigots (hose-bibb vacuum breaker must be winterized). This device will help prevent a cross-connection, ensuring that your drinking water remains clean and safe.


Steps to protect your drinking water

  1. Help us identify potential locations in our service area where backflow can occur.  Complete this survey now!
  2. If necessary, contact the Authority to schedule a free assessment with our staff to assist you in finding and removing any potential cross-connection sources. 
  3. Remove any cross-connections you find or install an approved backflow prevention device (available at hardware stores) where needed.  A Water Authority representative is available to assist you with this process if needed.
  4. If you have a backflow prevention device installed by a certified plumber, have it tested annually or after any repairs.

BRWA Test and Maintenance Form

All contractors performing backflow prevention device testing within the BRWA water work systems are required to fill out this test and maintenance form.

List of Certified Backflow Testers

To have you company added to the Bedford Regional Water Authority List of Certified Backflow Testers, please fill out the application by clicking here.

Need help?

Contact the Authority at 540-586-7679 or

View information in our backflow prevention brochure.

Bedford Regional Water Authority
1723 Falling Creek Road • Bedford • VA 24523

Backflow Prevention