Cross connections are any avenue where a contaminated source can be siphoned 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 Administrative Code 327 IAC 8-10 and Columbus City Code require backflow prevention devices 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.  Indiana Department of Environmental Management’s (IDEM) 2016 Cross Connection Control and Backflow Prevention Manual  lists appropriate types of backflow devices based on the contamination hazard.

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.

Aqua Backflow is a private company that receives, maintains, and tracks backflow device test results for Columbus City Utilities. Aqua Backflow operates a secure website at www.TrackMyBackflow.com where your Certified Backflow Tester must register and submit backflow tests electronically. Each test entry will cost $9.95, which is payable directly to Aqua Backflow.

New devices or existing devices that have never been reported to Columbus City Utilities will not be found on the Aqua Backflow website. In that case, you must email the report to info@aquabackflow.com to have the device added to the website.

Irrigation systems for watering lawns, fields, etc. can be a cross connection hazard. Should the water pressure drop, pesticides, herbicides, animal waste, stagnant water, or other pollutants can be siphoned back into the drinking water supply. To prevent these contaminants from entering the drinking water, customers shall properly construct an air gap, or install an approved reduced pressure principle backflow preventer, pressure type vacuum breaker, or spill resistant vacuum breaker on the water line connecting the public water supply to any irrigation system.

Fire protection systems can be a cross connection hazard. Should the water pressure drop, stagnant water from the sprinkler lines in a building can be siphoned back into the drinking water supply. To prevent this from happening, customers are required to install the appropriate backflow prevention device on their fire line and have it tested annually. The type of backflow device required depends on the type of fire suppression system installed. The IDEM 2016 Cross Connection Control and Backflow Prevention Manual provides guidance on device selection.

Backflow devices for fire protection systems are typically found in underground vaults between the water main and the customer’s building and are typically double check valve assemblies. One of the most common reasons for double check valve failure is flooded vaults, which is normally caused by groundwater seeping into the vault. Per IDEM requirements, double check valve assemblies must not be subjected to flooding. A sump pump can be installed in the vault to keep it dry. This also protects other valves and meters in the vault from damage.