When a water line is connected to equipment containing a nonpotable substance, this is known as a cross-connection. Contamination may occur when water flows through a cross-connection from a non-potable source, such as a sprinkler system or heating and cooling unit, into the potable water system. This can happen through a process known as backflow.
There are more than 30,000 backflow prevention assemblies in use in the Tucson Water service area. The Arizona Department of Environmental Quality requires that each be tested annually. A list of Tucson Water-approved Certified Testers 
is available. Call 520-791-2650 if you would like more information.
General Information
- Backflow Prevention Brochure
- Most Requested Information
- Cross Connection Control Specialist Zones & Contact Information
- Protect Your Backflow Prevention Assembly
- Irrigation Systems & Backflow Prevention Requirements
- Alternative Water Sources and Backflow Assembly Requirements
Testers and Contractors
- Backflow Assembly Test Results Data Entry, iBAK
- Videos - Tucson Water-approved Backflow Assembly Test Procedures
- Advance Purchase Request For Backflow Permit
- Backflow Prevention Installation Permit
- Backflow Prevention Assembly Test and Maintenance Report
- Multiple Annual Backflow Prevention Assembly Compliance Date Change Request
- Property-Meter Location Grid
