The Riverdale Fire Department owes it's roots to the foresight of Sergeant Owen Mulligan who utilized a local hose/reel company to extinguish fires within Riverdale up to the time the Riverdale Fire Department was officially organized. During his tenure, Sergeant Mulligan and others would respond to cries for help and for fires within the area, most probably with a bucket brigade type operation. There is little record of any apparatus used at the time, other than the hand made hose/chemical cart. This was a device that utilized a chemical reaction to achieve water pressure in the attached hose and nozzle. If there were a need for emergency assistance, these men did their best with the resources at hand.

In the early 1920s, the Riverdale Park Company, a coal fuel company in Riverdale, proceeded to purchase the land around the Calvert Mansion in Riverdale to be re-subdivided into an area to be called Riverdale Park Subdivision. During this time, the Riverdale Park Company, Sergeant Mulligan and like minded individuals provided a fire service to the citizens of Riverdale and to protect the homes under construction in the area.

The firemen in Riverdale along with Sergeant Mulligan had made a hose/chemical cart in the early 1910s for fire fighting within the town, and although this unit was adequate for fire fighting at the time, it was difficult to use because it had to be hand drawn to the scene of a fire, creating at times an insurmountable delay. Since the hose/chemical cart had some value, an additional unit was built by the volunteers in 1927 for the west side of the B & O Railroad tracks and housed in a garage used by the Riverdale Park Company, alongside their offices in Riverdale. These chemical carts were so soundly made that one still exists on display in it's original condition at the Leznick Fire Museum in Manassas, Virginia.