A cross-connection is any temporary or permanent connection between a public water system or consumer’s potable drinking water system, and any source or system containing nonpotable water or other substances. If a cross-connection exists, then it is possible for the contaminant to enter the potable community water supply through backflow. Backflow is the undesirable reversal of flow of nonpotable water or other substances through a cross-connection, and into the piping of a public water system or consumer’s potable water system. There are two types of backflow--backpressure backflow and back-siphonage. Section 62-550 of the Florida Administrative Code requires public water systems to establish cross connection control programs to detect, prevent and eliminate cross-connections that may create an imminent and substantial danger to the public health.
The most common form of cross-connection is the ordinary garden hose which can easily be connected to the potable water supply and used for a variety of potentially dangerous applications. It may be used with a sprayer attachment for spraying various chemicals on lawns and shrubs. The hose may be left submerged in a swimming pool, hot tub or simply left on the ground in a puddle which may be contaminated with fertilizer or other garden chemicals. If a pressure drop occurs in the system so as to create back-siphoning, these contaminants may be drawn back into the lines providing a potentially hazardous situation.
One of the most effective ways to protect our drinking water is to prevent contaminants on the outside of the water distribution system from being pulled back into the public water supply when a cross connection exists. To prevent backflow from occurring, the cross connection must be eliminated by installing an approved backflow prevention device on the water Service line. GIWA updated their Cross-Connection Control Program in February 2015 which requires backflow prevention at each water service connection. The following is a summary of the requirements:
Testable backflow prevention assemblies must be tested by a State of Florida Certified Tester when installed or repaired, and annually tested thereafter to ensure it operates properly. GIWA provides annual tests (excluding fire suppression systems) free of charge. Non-testable devices must be replaced every five (5) years.