Backflow Prevention Program


The Environmental Services Section of the Water Utilities Division of the Public Works Department is responsible for administering the City of Tempe’s Backflow Prevention Program, which is a containment program. An example of containment and internal protection is provided below:

Example of containment and internal protection

1. The City of Tempe water meter. The user paying the water bill will receive the test notification letter. The test notice will provide the meter number and service address as listed in the City of Tempe billing system. In order to enter a test into CDS, the correct meter number is required.
2. The RP serves as containment by preventing backsiphonage / backflow of water into the public water supply.
3. The PVB serves as isolation by preventing backsiphonage of water into the user’s water system.
4. Fire lines should be protected by use of a double check assembly located either outside or inside the Fire Riser room. The first check valve closes as a result of backsiphonage and the second check valve closes as a result of backpressure.

The purpose of the Backflow program, is to protect the public water supply from contamination or pollution by isolating within the user’s system such contaminants or pollutants which could backflow into the public water supply, and to provide for the monitoring and enforcement of the program. This is accomplished by inspecting service connections to determine compliance with Tempe City Code related to backflow, tracking the annual testing of privately-owned backflow prevention assemblies (“assemblies”) to ensure proper operation, and investigating water quality complaints and backflow incidents.

Responsibility of the User

Pursuant to Tempe City Code Chapter 33, Section 107(a), the user is responsible for maintaining accurate records of tests and repairs made to the assembly. Section 107(b) requires the user, at their own expense, to have a certified backflow prevention assembly tester that is registered with the City, test the assembly at the initial installation and then annually on the anniversary date of the initial test. It is recommended the user maintain these records of testing and repairs for a minimum of three (3) years. Section 107(c) of the Code specifies the user is required to notify the City 15 days in advance when the yearly test(s) are to be conducted so an Inspector may witness the test, if so desired. Typically the City waives this requirement. In those instances where there may be cause for the City to witness the test, the City will notify the user well in advance.

Test Notification Letter

Assembly test notification letters will be issued to the user paying for the water service. Up to three notices will be issued. The first notice will be issued 90 days prior to the annual test due date. If required, a second notice will be issued 30 days prior to the due date and a Final Notice will be issued if the test was not completed and posted by the assembly due date.

Data Management & Tester Registration

The City has updated the data structure used to track assembly test dates, tester certification, and test kit calibration. The web based “Compliance Data System (“CDS”) tracks the certification of each registered tester as well as their test kit(s). Certified backflow assembly testers, conducting testing within the City of Tempe, must be registered in CDS. The tester’s name, company name, and contact information will be used to provide users with a listing of registered testers, which replaces the former “Recognized Tester List.”

In order to create an account in CDS, the tester must possess a current backflow prevention assembly tester certificate and test kit calibration report. The dates of issuance and expiration of each certificate and the PDF of the two certificates are stored in the CDS. It is the tester’s responsibility to maintain their tester certification and yearly test kit calibration report. Testers are no longer required to submit hard copies of the certificates. In lieu of submitting hard copies, each registered tester will have the ability to update expiration dates and test kit calibration reports.

Tester Responsibility

The CDS Backflow Module was designed to allow the registered tester to input the results of the annual backflow assembly test. The notice issued to the user paying the water bill will include the service address and the meter identification number. This data comes directly from the Utility Billing System. All test results are to be inputted into CDS by the tester. The City does not charge the user or the individual conducting the test. When completing the test, the tester should provide the user with a hard copy of the report. The report must contain the correct service address, meter ID number as listed on the test notice, make, model, and serial number of the assembly. The tester is no longer required to use a City of Tempe form. The CDS developer is designing an IOS and Droid app for use on smart phones and tablets that will allow the tester to input the results while conducting the test. A reporting feature will allow the tester to email a portable document format (“PDF”) of the test report to the assembly owner. The developer may charge a nominal fee to for the app. When the apps are completed and ready for distribution, an email will be issued to all registered testers. It is extremely important that the tester keep his/her registration and email contact information up to date in order to receive notifications from the City.

When the CDS data entry portion of the Backflow Module is made available, each tester will receive by email written procedures for entering results. Again, it is imperative for the tester to keep their email address up to date.

Stolen Backflow Assembly

If your backflow assembly is stolen, please report this theft to the City of Tempe Police Department. Use the non-emergency number of (480) 350-8311 to file the report. By providing the responding officer with the make, model, size, and serial number of the stolen assembly, valuable time is saved for the Police Department and the Water Utilities Division. The City aggressively investigates thefts of assemblies and arrests have been made.

The user must replace the stolen assembly in a timely manner and the assembly must be replaced with the same type of assembly. Security of the assembly should be increased by use of a cage, locking mechanism, and/or converting to a style of assembly which contains less brass. To be in compliance with Tempe City Code Chapter 33, Section 107(e), a plumbing permit is required if the assembly is replaced and/or relocated. If the assembly is relocated, it may no longer be serving as containment. Please contact the Environmental Services Section at (480) 350-2678 if you need assistance.

Link to CDS 

List of Registered Testers

Backflow Tester Registration Instructions