Backflow Testing

Backflow Testing

Backflow testing helps ensure that dirty water is not making its way into your drinking water supply.  This is not something you can test for yourself. Only a state-certified plumber can perform your backflow testing. The State of Maryland requires all testable backflow assemblies (including those used on irrigation systems) to be tested on an annual basis.

We are certified to conduct backflow testing on your backflow preventer device. As Certified Backflow Prevention Mechanics, we frequently work with commercial clients, homeowners associations, and individual homeowners. After you schedule an appointment convenient to you, we will test your backflow and file the test report with the proper bureau.



In the state of Maryland,

“Personnel who perform backflow prevention inspection, testing and overhaul must be certified (32 hour training class) as a Backflow Prevention Mechanic by the Maryland Plumbing, Heating and Air Conditioning Contractor’s Association.”

For more information on certification requirements for backflow testing or inspection of backflow devices, please visit the backflow prevention fact sheet from the University of Maryland.

What is Backflow? 

Picture your building’s system having a gag-reflex, or acid reflux — that’s backflow. In the water-supply infrastructure of a building, water is normally kept under constant pressure. This keeps the dirty sewage water from flowing backwards into your structure and makes sure it stays in designated local sewage storage. But sometimes, water pressure can decrease, due to things like frozen pipes, water-main bursts, or an abnormally high demand on the water system itself. This isn’t good. It can actually cause backflow contamination. There are more than 10,000 reported cases of backflow contamination each year; some of which are actually lethal.

What is Backflow Prevention?

Certified Backflow Prevention Mechanics perform what is technically known as backflow prevention assembly and backflow testing.

The backflow prevention assembly and testing actually revolves around the installation and subsequent annual testing of backflow preventers. A backflow preventer is a backflow valve (known technically in plumbing as a check valve – see the photo of a typical residential backflow valve below). Commercial & Industrial systems generally require an RP (reduced pressure) device, a double-detector check, or an air gap, for proper backflow certification.

Areas We Serve for Backflow Testing Services

Harford County

Aberdeen, Aberdeen Proving Ground, Abingdon, Bel Air, Belcamp, Benson, Churchville, Darlington, Edgewood, Fallston, Forest Hill, Gunpowder, Havre De Grace, Jarrettsville, Joppa, Perryman, Pylesville, Street, White Hall, and Whiteford

Baltimore County

Arbutus, Bowleys Quarters, Carney, Catonsville, Cockeysville, Dundalk, Edgemere, Essex, Garrison, Hampton, Kingsville, Lochearn, Lutherville, Middle River, Overlea, Owings Mills, Parkville, Perry Hall, Pikesville, Randallstown, Reisterstown, Rosedale, Rossville, Towson, and White Marsh

Prince George’s County

Bowie, College Park, Greenbelt, Hyattsville, Laurel, New Carrollton

Montgomery County

Ashton, Barnesville, Bethesda, Brookeville, Cabin John, Chevy Chas, Clarksburg, Damascus, Gaithersburg, Germantown, Kensington, Olney, Poolesville, Potomac, Rockville, Sandy Spring, Silver Spring, and Takoma Park

Baltimore City

Federal Hill, Canton, Harbour East, Fells and Fells Point

Howard County

Columbia, Elkridge, North Laurel, West Friendship, Highland, Ellicott City, Fulton, Glenelg, Woodstock, Dayton

Anne Arundel County

Annapolis, Crofton, Edgewater, Fort Meade, Deale, Ferndale, Glen Burnie, Severna Park, Arnold, Crownsville, Cape Saint Claire, Pasadena, Severn, Gambrills, Odenton, Millersville, and Linthicum Heights

Don’t see your town or city listed? Call us at Call (410) 836-0118 for immediate service!


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