Commercial Plumbing in Rockville, MD

Is our Rockville building on City water or WSSC?

It depends on the address. The City's water system covers roughly 70% of Rockville, around 13,500 accounts, and WSSC Water serves the remainder. The City publishes a Water Service Provider Map, and your water bill also shows the answer. City water comes from the Potomac River and is treated at the City's own plant, which switched from chlorine gas to liquid sodium hypochlorite for disinfection; when that plant is offline the City buys Potomac water from WSSC. WSSC-served buildings get the WSSC blend from the Potomac and Patuxent plants.

Where do commercial plumbing permits come from?

The same map answers this. Rockville's own permit guide says addresses on WSSC water get their plumbing permit, including a water heater permit, from WSSC Water Permit Services (301-206-4003). Addresses on City water apply to the City's Department of Community Planning and Development Services through its online system. As Montgomery County's seat and a hub for biotech, software and federal employers, Rockville sees many tenant build-outs, so settling which office applies before the plumber starts saves time. For backflow, WSSC-served properties fall under WSSC's yearly testing rule, with results filed electronically by a registered principal master plumber (program line 301-206-4004). Owners on City water should ask the City what it requires for their assemblies.

Who do we call for a main break or sewer backup?

City-served areas use the City of Rockville's 24-hour emergency line, 240-314-8567, for water main breaks and sewer backups. WSSC-served buildings call WSSC at 301-206-4002. Anything inside your walls or on your private line is for a plumber. If the problem is a gas smell, leave first, then call 911 and Washington Gas at 844-WASHGAS (927-4427), option 1, from outside.

A note on Rockville building stock

The median Rockville home dates to 1980, and the city mixes postwar neighborhoods like Twinbrook with a redeveloped Town Center and newer offices along I-270. That spread means one call might be a cast iron drain in an older strip of shops and the next a tankless bank in a recent lab building. The City has completed a service line material inventory and says it is responsible for removing lead pipes it owns, while customers share responsibility for the plumbing inside their property.