Cross connections are any avenue where a contaminated source can migrate or be “sucked” back into the public water distribution system.  Under normal circumstances, this doesn’t happen because the system maintains a positive pressure that keeps the flow of water going in one direction, out to the customer.  But there are circumstances, like a major fire response, or a broken water main, where the pressure in the water pipes may fall low enough to cause water to reverse its course and move from the customer’s line back into the system.  If the customer’s end of the line is connected to a contaminant like a hose in a bucket of cleaner or a lawn sprinkler head at or below ground level, then these contaminants can be pulled back into the public supply, endangering everyone.

To protect against this, Indiana law requires devices that restrict flow to only one direction be placed on the customer’s line where contaminants are present or likely.  There are various types of backflow prevention devices manufactured and the type of device installed is dependent on the potential contaminant being protected against.  One of the simplest and least expensive of these devices is called the vacuum pressure breaker and is commonly installed as part of in-ground irrigation systems.  To be effective it must be installed before and above the sprinkler heads.

All backflow devices require regular annual testing by a certified backflow device technician to ensure their viability.  Indiana requires Columbus City Utilities, as a public conveyor of water, to maintain an inventory of all backflow devices connected to the system, as well as to ensure these devices are properly tested.  To aid in this, Columbus City Utilities has contracted with Aqua Backflow who assists in contacting device holders and recording test results in a central database we can make accessible to State regulators upon request.

Links

IDEM

EPA

Aqua Backflow

American Backflow Association