Backflow Testing in Greenbelt, MD

What happens when you call

Your call goes to an independent plumber who works in Greenbelt. Expect a few questions: what the assembly protects (lawn irrigation, a fire sprinkler line, a boiler or a commercial process), roughly where it sits, and whether you have a notice or a past test report. In a co-op townhouse or a building in Springhill Lake or Lakeside, it also helps to know whether the device belongs to your unit or the association. The plumber then sets a time, tests the device with a calibrated gauge and tells you whether it passed.

If it fails, most repairs are done during the same visit with a rebuild kit for the checks or relief valve, followed by a retest. A cracked or badly corroded body usually means a new assembly, which needs a WSSC permit before installation and its own test afterward.

What affects the cost

• Type. RPZ assemblies have more parts to test and rebuild than a vacuum breaker or double check.
• Result. A pass is quick; a failure adds parts, labor and a second test.
• Location. A device in a crawl space, ceiling or crowded mechanical room takes longer than a yard riser.
• Count. Multifamily and commercial properties near Greenbelt Road or the Metro station may have several.
• Permits. Replacement needs a WSSC permit, and projects that need a county building permit also need a City of Greenbelt permit.

Local conditions in Greenbelt

Greenbelt began as a New Deal planned town, and the median home here dates to 1976. Original homes in Old Greenbelt seldom came with sprinkler systems, but yards that were improved later sometimes have in-ground irrigation, and that is where most residential assemblies show up. WSSC wants lawn irrigation assemblies tested once a year, with the test reported at spring start-up. Homes built between 2007 and 2009 with testable dual check valves on fire sprinkler systems must have them tested or replaced.

WSSC's tap water analysis shows water from its Potomac plant averaging about 140 mg/L of hardness and water from its Patuxent plant about 64 mg/L, and which plant serves a given address varies. Harder water can leave mineral deposits on check seats over time, another reason a device that once passed starts to leak.

Checklist before the plumber arrives

• Clear plants, mulch or stored items away from the device
• Know where the main shutoff and irrigation shutoff are
• Have any WSSC notice or old test report handy
• Tell household members water may be off briefly
• For co-op or condo homes, confirm who owns the assembly