Stolen Backflow Preventer Replacement

A stolen backflow preventer usually leaves a cut pipe on both ends and water running from the upstream side. That's stressful, and it's fixable. Do these in order.

1. 1Close the valve upstream of the cut. That's the valve between the water meter and where the assembly used to be. If thieves cut above every valve you can reach, call your water provider's customer service line and ask them to shut the service.
2. 2Photograph the empty spot before anyone touches it.
3. 3Call police on the non-emergency line. Tempe's program page asks for the make, model, size and serial number, and says the city "aggressively investigates thefts of assemblies and arrests have been made."
4. 4Call your water provider's backflow office. The assembly is in their inventory with a test due date. They need to know it's gone.
5. 5Pull your last test report. It has the serial number and model. Phoenix's report form records the manufacturer, size, model and serial number for every assembly.

Why are they stolen? Brass. Arizona law, A.R.S. 44-1642.01, bars scrap dealers from knowingly buying brass or bronze commercial potable water backflow preventer valves. The statute names these valves by description, right next to manhole covers and water meters.

The fastest way to get water back is a straight piece of pipe. Every Valley code treats that as a violation. Tempe City Code 33-104(c) says no bypass shall be installed around backflow prevention assemblies. Phoenix can terminate service when a customer "removes or bypasses a required backflow prevention assembly" without the Planning and Development Director's approval (City Code 37-146). Mesa can terminate when protection "has been removed or bypassed" (City Code 8-1-13). Phoenix's tester guidance quotes the plumbing code: no assembly may be removed from use or substituted without the authority's approval (TRT 00636).

So if the building truly can't wait, ask the city's backflow office what it will accept in the meantime, and get the answer in writing. In most cases the quickest legal path is a same-day replacement.

A stolen assembly is replaced like any other, just faster.

• Same type. Tempe says it in so many words: a stolen assembly is replaced with the same type. An RP goes back as an RP. The city picked that type for your site's hazard. See backflow assembly replacement for how type is chosen.
• Same size or larger than the service. Mesa requires the assembly's diameter to at least equal the service connection.
• Permit where required. Tempe's program page requires a plumbing permit when a stolen assembly is replaced. Rules elsewhere differ, so we check the city before we set it.
• Tested before the water goes back on. Arizona's rule bars placing an assembly in service until it is tested and works as designed. Phoenix's report form then asks for the serial number of the assembly that was replaced.

The cut piping usually needs new nipples or spool pieces on each side, since thieves don't cut cleanly. That's part of the same visit.

Tempe suggests a cage, a locking mechanism, or an assembly style with less brass. Whatever you add still has to meet the location rules. Phoenix City Code 37-144 requires every assembly to stay accessible for testing and maintenance, and bars RP and double check assemblies from basements, meter boxes, pits and vaults. So burying it isn't an option, and moving it out of sight counts as a relocation. Tempe also warns that a relocated assembly "may no longer be serving as containment." See backflow assembly relocation before you move one.

An enclosure also has to let an RP's relief water drain away. For options, read whether you need an RPZ hot box and the FAQ on what to do when a backflow preventer is stolen.

HQ replaces stolen domestic backflow assemblies with 24/7 emergency service. We stop the water, rebuild the cut piping, set the same type and size, test the new assembly and file the report with the city. Fire backflow assemblies and fire sprinkler work are outside what HQ does, so a stolen fire line assembly goes to your fire protection contractor.

Tell us the city and, if you have it, the last test report when you call. You get an upfront price before work starts. Related: emergency plumber, commercial plumbing, HOA plumbing and property management plumbing.