Backflow Testing in District Heights, MD

Local conditions in District Heights

District Heights is a small, fully built-out city that started as farmland, and many of its Cape Cod-style homes date to the 1940s, when builders put up affordable single-family houses with FHA financing. The citywide median build year is 1968. Houses from those decades were built without backflow assemblies, so a homeowner here usually meets one only after adding a sprinkler system, a hydronic boiler with treatment chemicals or a fire sprinkler line. Churches, shops and apartment buildings along MD 458 are more likely to have devices on their main service.

WSSC, not the city or county, issues and inspects plumbing permits here, and Prince George's County notes that testable backflow devices need a permit even though like-for-like fixture swaps generally don't. For non-plumbing building permits, the county publishes a matrix showing which jobs belong to the county and which to the municipality. WSSC Permit Services is at 301-206-4003, and the county's cross-connection line is 301-206-8601.

Repair versus replacement

Either way, the assembly is tested again once the work is done, and a replacement goes through a WSSC permit first.

Signs to watch for

• A WSSC letter saying a test is due
• A relief port that drips or runs
• Low pressure on the sprinkler or boiler feed
• Cracks, corrosion or a damaged test cock
• No record of any test since you bought the home

Seasonal timing

Irrigation devices are best tested when the system starts up in spring. Fall is the time to drain them, since an assembly holding water through a hard freeze can split. Boiler devices sit indoors and can be tested any time, though booking before the heating season avoids a shutoff on a cold day. Keep each year's report with your house records.