Possibly, and for a different reason. A property with both a well and a municipal connection creates a path between two supplies, which is treated as a high hazard. A well-only property has different considerations. A cross-connection survey answers it properly.
The assembly needs repair or replacement, and your water supplier will expect a passing retest. Many failures are a worn seal or weak spring and can be rebuilt rather than replaced, which is usually the cheaper route. We will tell you which applies before doing the work.
You cannot tell by looking, and that is precisely why testing exists. A failed assembly still passes water normally in the forward direction, so nothing about your plumbing behaves differently. Only a gauge test reveals it.
No. Testing requires a current backflow prevention assembly tester certification and a calibrated differential pressure gauge. Water suppliers will not accept results from an uncertified tester, and gauges must be recalibrated periodically to stay valid.
Usually under an hour. Your water is shut off briefly while each valve in the assembly is checked with a differential pressure gauge, then the results are filed with your water supplier.
Annually in most Maryland jurisdictions that require testing. Some water suppliers allow a two-year interval for low-hazard residential devices. Your supplier sets the schedule and often sends a reminder notice when a test is due.
