Cross Connection (Backflow) Control Program

Toilet with pipe going into itProtecting the Public Water System

The purpose of the Town's Cross-Connection Control Program is to protect the public potable water supply; to promote the elimination or control of existing cross-connections between potable water systems and non-potable systems; and to provide for the maintenance of a continuing program of cross-connection control which will effectively prevent the possible contamination or pollution of all potable water systems by cross-connection.

The Town is committed to protecting the public water system from contamination due to backflow or backsiphonage of connections containing non-potable water.

Backpressure cross contamination can occur when the pressure in equipment or a system is greater than the pressure in the drinking water system. Backsiphonage contamination can also occur when the pressure in the drinking water line drops due to occurrences such as main breaks and heavy water demand causing contaminants to be sucked out from equipment and into the drinking water system.

Backflow Device Testing

Every six months, as required by Massachusetts Drinking Water Regulations (PDF), the Water Division performs backflow device testing as a fee for service program. Devices are tested and a report is given to the property owner. Follow up tests are performed if the device failed the initial test. Repairs to backflow preventers are repaired by independent firms at the owner's expense. Reporting and management of survey and testing reports is the responsibility of Town of Needham. Conditions of the systems are reported to the Mass Department of Environmental Protection (DEP).

Common Sources of Cross Connections

Outside water taps and garden hoses tend to be the most common sources of cross-connection contamination at home. The garden hose creates a hazard when submerged in a swimming pool or when attached to a chemical sprayer for weed killing. Water suppliers are required to survey all industrial, commercial, and institutional facilities to ensure all cross connections are identified and eliminated or protected by an appropriate device.

A Backflow Preventer is required for:

  • Permanently-installed irrigation systems. (This includes residential in-ground sprinkler systems);
  • Industrial, commercial or institutional premises having a private well or other private water source with a cross-connected to the public water system. (Permission for such cross-connections may be denied by the Commission); Backflow Prevention Device Application 
  • Property that contains a private well or individual water source that does not serve a residential dwelling. (A private well or individual water source serving residential dwellings used for potable or non-potable purposes will not be allowed a physical connection with the public water supply system.)

The Cross-Connection (Backflow) Control Program requires that:

  • The owner shall be responsible for the elimination or protection of all cross-connections on his or her property;
  • The owner shall be responsible for applying for and obtaining all necessary approvals and permits for the maintenance of cross-connections and installation of backflow prevention devices;
  • The owner shall correct any malfunction of the backflow preventer that is revealed by periodic testing;
  • The owner shall inform the Commission of any proposed or modified cross-connections and also any existing cross-connections of which the owner is aware but has not been identified by the Commission;
  • The owner shall not install a bypass around any back-flow preventer unless there is a backflow preventer of the same type on the bypass. Owners who cannot shut down operations for testing of the device(s) must supply additional devices necessary to allow testing to take place;
  • The owner shall install backflow preventers in a manner approved by the Commission;
  • The owner shall install only backflow preventers approved by the MassDEP; 
  • The owner of industrial, commercial or institutional premises having a private well or other private water source must have a permit if the well or source is cross-connected to the Commission's system. Permission to cross-connect may be denied by the Commission. The owner may be required to install a backflow preventer at the service entrance if a private water source is maintained even if it is not cross-connected to the Commission's system; 
  • The owner of a private well or individual water source serving residential dwellings used for potable or non-potable purposes will not be allowed a physical connection with the public water supply system;
  • The Commission may require the owner of a property that contains a private well or individual water source that does not serve a residential dwelling to install a backflow preventer if in their opinion the potential for cross-connection exists;
  • The owner of a permanently installed irrigation system shall install, at minimum, a testable pressure vacuum breaker. Failure to maintain a device in proper working order or failure to provide proof of testing will result in termination of service;
  • The owner shall be responsible for the payment of all fees for permits, annual or semi-annual device testing, retesting in the case that the device fails to operate correctly, and second re-inspections for non-compliance with MassDEP regulations.