Chandler City Code 52-36: backflow assemblies on commercial building plans

Section 52-36 is Chandler's backflow prevention policy. Subsection (H) says: "Assemblies shall be specified and located on the construction plans for all new buildings, additions with new services, and changes of use of existing buildings. Approval shall be obtained prior to issuance of the building permit." The rule does not apply to building permits applied for before the article took effect on November 1, 1990.

The rest of 52-36 shapes what goes on those plans:

• Shutoff: the city may discontinue water service if a required device is not installed, tested and maintained, if it has been removed or bypassed, or if an unprotected cross-connection exists (52-36(A)).
• Device by hazard (D): an air gap or reduced pressure principle assembly where there is an auxiliary supply, a health hazard or an uncontrolled cross-connection; a double check valve assembly where the substance is objectionable but not hazardous to health.
• Approved devices (F): the model and size must be approved by the Director of Public Works and Utilities, listed by the Foundation for Cross-Connection Control and Hydraulic Research, and have a local parts and service center. Fire line assemblies also need UL-FM approval.
• Size (E): at least the same cross-sectional area as the water service or meter. Where the supply cannot be interrupted for testing, two sets of assemblies in parallel.
• Annual test (G): inspections, operational tests and repairs at least once a year, at the owner's expense, by the device manufacturer's representative or a certified tester approved by the Director.

• Backflow assembly: a valve arrangement that keeps water from flowing backward into the city system.
• Change of use: a new kind of business in an existing building, such as an office becoming a restaurant. The code does not define it, so ask the city if yours is a gray area.
• Additions with new services: an addition that gets its own water connection. An addition served from the existing service is not named in the rule.

It covers commercial and other non-house work: new buildings, additions with new services and changes of use. It does not cover a like-for-like device swap in an existing building, which falls under the annual test and maintenance rules instead. The section's Subsection I lets older approved devices stay, except for inspection and maintenance, until they are moved or need more than minimum maintenance.

A new restaurant shell. The designer draws the plumbing and leaves the backflow assembly for the plumber to add later. The permit is not issued until the city approves the assemblies shown on the plans.

A change of use. A tenant moves in and the kitchen needs a bigger water service. The plan set now shows a new service, so the assembly, its location and its type by hazard belong on the drawings.

The edge case: a hazardous-material tenant. A facility that handles hazardous materials that pose a risk to the water system flips who tests. Under City Code 52-37, the city picks an independent agent to test the assemblies and bills the owner a surcharge, so the owner cannot use their own tester. Separately, (D)(3) requires an air gap or reduced pressure assembly where material dangerous to health is handled, and names hospitals, mortuaries, plating plants and sewage plants as examples.

1. 1Put every backflow assembly on the plumbing plans with its location and hazard-based type.
2. 2Pick from the city's approved list, since 52-36(F) requires the Director's approval of model and size.
3. 3Submit the plans to Chandler Development Services (215 E. Buffalo St., 480-782-3000) with the permit application, and wait for the approval before the building permit issues.
4. 4After installation, pick a tester from the city's approved list at chandleraz.gov/residents/water/water-quality/backflow-testing-companies and schedule the annual test.
5. 5Send each annual test report to Chandler Backflow Reports, 480-782-3665. The city's testing process page says it sends a first notice 60 days before the due date, and water can be shut off if no passing report arrives. Keep the test, repair and overhaul records, because City Code 52-37(F) says they must be made available to the Director.

• "Backflow is a plumber's punch-list item." In Chandler it is a plan item, approved before the building permit.
• "Any device works if it is the right type." It must be approved for use and have a local service center.
• "Once installed, it is done." The code requires testing at least once a year.