A cross-connection is a permanent or temporary piping arrangement, which can allow your drinking water to be contaminated if a backflow or backsiphonage condition occurs.

It’s just what it sounds like: the water is flowing in the opposite direction from its normal flow. With the direction of flow reversed, due to a change in pressure, backflow can allow contaminants to enter our drinking water system through cross-connections. A potentially hazardous cross-connection occurs every time someone uses a garden hose to clear a stoppage in their sewer line. Other cross-connections can occur when someone uses his or her garden hose to clear a stoppage in their sewer line; fill a pool while leaving the hose in the water and having an automatic timer set on their hose.

Without a backflow prevention device between your hose and hose bib (spigot or outside faucet), the contents of the hose and anything it is connected to can backflow into the piping system and contaminate your drinking water.

Plenty. When water is delivered to your property it is exposed to many different types of fixtures, including sprinklers, washing machines, hose-bibs, kitchen faucets, tubs, showers, and toilets. For industrial users, the system may be attached to boilers, photo processing equipment, chemical mixing tanks, chillers, water towers, pressure pumps, healthcare and laboratory equipment, etc. Connections between the potable water system and potential sources of pollution, or contamination, are called “cross-connections.” When backflow occurs through a cross-connection, there is a chance that contaminants can be drawn into the public water system.

Backflow Device Testing

Air Gaps (AG) shall be inspected at intervals not exceeding one (1) year to ensure that they continue to meet the requirements.
Definition: A physical separation between the free-flowing discharge end of a potable water supply pipeline and an open or non-pressure receiving vessel. An approved air gap shall be at least double the diameter of the supply pipe measured vertically above the overflow rim of the vessel – in no case less than one inch and nor more than 6 inches unless around walls.

Reduced Pressure Principle Backflow Prevention Assembly (RP) shall be tested at intervals not exceeding one (1) year to ensure that both check valves are drip tight under all pressure differentials and that the pressure differential relief valve will open in pressure changes below two pounds per square inch below that of the inlet chamber.
Definition: A device composed of two tightly closing shut-off valves surrounding two independently acting pressure reducing check valves that, in turn, surround an automatic pressure differential relief valve, and four test cocks, one upstream of the five valves and one between each of the four check and shut-off valves. The check valves effectively divide the structure into three chambers, pressure is reduced in each downstream chamber allowing the pressure differential relief valve to vent the chamber to atmosphere should either or both check valves malfunction.

Double Check Valve Backflow Prevention Assembly (DC) shall be tested at intervals not exceeding one (1) year to ensure that both check valves hold pressure at 2.0 or greater under all pressure differentials.
Definition: A device or assembly composed of two tightly closing shut-off valves surrounding two independently acting check valves, with four test cocks, one upstream of the four valves and one between each of the four check and shut-off valves.

Double Check-Detector Backflow Prevention Assembly (DCDA) shall be tested at intervals not exceeding one (1) year to ensure that both check valves hold pressure and do not leak under all pressure differentials.
Definition: A specifically designed assembly composed of a line-size approved double check valve assembly second main line with backflow preventer before the meter containing a specific water meter and an approved double check valve assembly.

Pressure Vacuum Breakers (PVB) shall be tested at intervals not exceeding one (1) year to ensure that the air inlet opens fully when water pressure and the check valve holds closed under pressure.
Definition: A device or assembly containing an independently operating internally loaded check valve and an independently operating loaded air inlet valve located on the downstream side of the check valve for relieving a vacuum or partial vacuum in a pipeline.

Who can test these devices?
Testers are certified by the State of Indiana after attending a 40-hour training class, passing 2 written examinations, and successfully completing actual tests on prevention devices. When you need to contact a tester, we suggest contacting your irrigation contractor first. Many of the contractors and/or their employees are certified. Secondly, check the Yellow Pages under Backflow Prevention. The City of Nappanee Utilities does not recommend individuals to do testing.

City of Nappanee ordinance A-69, states under what conditions existing facilities (those facilities existing prior to the adoption of the ordinance) must comply with cross-connection control requirements. Briefly, all existing buildings, which house a business activity and are operated as such, will be required to comply with this chapter upon the occurrence of any one of the following events:

1. New ownership of building;
2. Remodeling; 
3. Change of occupancy;
4. Installation of a new service line or upgrade of service;
5. Addition of machinery or chemicals;
6. Designated a cross-connection hazard or;
7. If backflow occurs.