Water Supply Cross Connection Control

Picture of kitchen waterProgram Goals

To protect the public water supply against backflow contamination caused by back pressure or back siphonage (referred to as “backflow”). Plumbing cross-connections are defined as actual or potential connections between a potable and non-potable water supply, and can pose a significant public health hazard.

Legal Authority

New York State Public Health Law, Article 225: Title 10 NYS Codes, Rules and Regulations, Part 5-1.31.

Program Highlights

  • Review and approve plans and specifications for the installation of backflow prevention devices.
  • Consult with NYSDOH, suppliers of water, design engineers, mechanical contractors, plumbers, NYSDOH certified backflow device testers and concerned citizens.
  • Conduct site and construction inspections as necessary.
  • Issue Completed Works Approvals.
  • Investigate complaints.
  • Conduct enforcement actions.


Application is made by filling out the New York State Department of Health form titled, Application For Approval of Backflow Prevention Devices, “DOH-347.” Plans, specifications and an engineer’s report describing the project in detail must accompany all applications. The project must first be submitted to the local water supply official for review. The water supplier will then forward the submittal to the Monroe County Department of Public Health for review. The water supplier will forward the application packet, with accompanying signature by a designated representative, and a letter of authorization. Four copies of the application, plans, specifications and descriptive literature must be submitted.

Cross Connection Documents

Online Information