Group B Public Water Systems - Cross Connection

Cross-Connection Control

A cross-connection is any actual or potential physical connection between a public water system and a source of non-potable liquid, solid or gas that could contaminate the potable water supply with backflow.

For most residential Group B systems, home agriculture practices such as irrigation, “chemigation,” and raising farm animals pose the likeliest risks of contamination from cross-connections.

Group B systems that serve commercial or industrial customers have much more to consider. Toxic, pathogenic, or hazardous compounds could be present in a commercial or industrial facility. Improper plumbing or operational practices may pose a health risk if backflow were to occur.

If your Group B system serves only one building, then the state plumbing code establishes backflow prevention requirements for plumbing fixtures and equipment.

If your Group B serves more than one building or more than one service connection, the following recommendations apply:

  • Establish the legal authority, policies, and corrective measures needed to implement effective cross-connection control.
  • A cross-connection control specialist (CCS) should be consulted to conduct initial and periodic inspections of all buildings served by the water system.
  • Install approved backflow preventers where required. Your CCS will have a list of approved assemblies.
  • A certified backflow assembly tester (BAT) must be used to conduct testing of any backflow device. Backflow assemblies should be tested at least annually.
  • Develop procedures for responding to a backflow incident (such as an immediate public notice (Word) to all your customers).
  • Maintain all backflow assembly testing inspection records produced by the CCS and BAT.
  • The cross-connection control (CCC) program for your Group B water systems involves initial and ongoing tasks. You can separate these tasks into three categories.
  1. CCC program development
    a. Consult with a CCS and develop a program plan.
    b. Describe your program and establish legal authority to implement it.
    c. Develop your response plan for a backflow incident.
  2. CCC program initial implementation
    a. Develop your record keeping and reporting system.
    b. Conduct an initial hazard evaluation with your CCS.
    c. Ensure the correct assemblies are installed wherever needed.
  3. CCC program ongoing implementation
    a. Ensure annual assembly testing by a BAT.
    b. Practice proper record-keeping of all test results and correspondences.
    c. Periodically re-evaluate service connections.

For more information

Detailed guidance to develop a CCC program for small systems is available on our web.

Specific guidance documents on developing a CCC program for your small water system include: