How to Determine if You Have a Residential Cross Connection
1. Lawn Irrigation Systems
Underground irrigation systems are a direct cross connection. A suitable backflow device, typically located on the side or back of your home, must be used to protect the public water supply. Surface water can be siphoned back into your plumbing system through an automated lawn irrigation system unless a proper backflow device is attached. If the system uses a pump or has fertilizer or chemical injection, additional backflow protection and testing is required.
2. Private Wells and Secondary Water Sources
A well or secondary water source on a property is a potential cross connection. Wells or secondary water sources are prohibited from being connected to the Lincoln Water System. A backflow preventer on the public water supply is always required at the meter when secondary sources of water are present on a customer’s property.
3. Swimming Pool or Hot Tubs
Pools and hot tubs that are permanently connected to the home plumbing systems are direct cross connections and must be protected with a suitable backflow device. An unprotected cross connection could draw pool water and chemicals back into your household plumbing system and public water supply. When filling a pool or hot tub with a hose, never submerge the end, as this is another cross connection. Always leave an air gap when filling pools, hot tubs, sinks or containers.
4. Home Medical, Dental or Dialysis Equipment
Similar to equipment found in medical offices, these devices are sometimes used in the home. When connected to the water supply, these cross connections must be protected with a suitable backflow device to prevent contamination of the home plumbing system and public water supply.
5. Boiler Systems for Heating
These systems are not common but do exist, normally in larger homes. Water is used to replenish the boiler, which may also have chemicals. This cross connection must be protected with a reduced pressure principle backflow device to prevent contamination of the home plumbing system and public water supply.
6. Other Suspected Cross Connections
A garden hose is the most common cross connection. A garden hose submerged in water in a sink or container with chemicals or fertilizer is a serious cross connection. A sudden drop in water pressure from a water main break or from water being used to fight a fire can siphon water back into your home plumbing system or the public water supply. A vacuum breaker is a simple and inexpensive device that can be installed on the faucet or hose to prevent contamination. Never leave the end of a hose submerged in a tub, sink, pool or container.
Most bathtubs and sinks have an air gap as backflow prevention. This space between the highest water level in the fixture and the outlet of the water is the best form of backflow protection.
Home use of photographic chemicals, process chemicals, biological lab supplies, and other chemicals can cause contamination due to an unprotected cross connection. Residential fire protection systems, in-home water treatment systems, car washes, solar heating, soaking tubs and decorative ponds are other possible cross connections.
Lincoln Water System is required by Nebraska Department of Environment and Energy to conduct a cross connection control program using the specific components below: