The High-Pressure Fire-Service Pumps were fed by cast-iron pipes 12" to 24" in diameter.

The pipes were fed by two pumping stations at Gansevoort and South Street. Each pump station consisted of five Allis Chalmer five-stage centrifugal pumps.

Each pump had a capacity of 3,000 gallons a minute with a suction lift of 20 feet. The delivery pressure of each hydrant was 300 pounds per square inch.

To adequately protect over fifty blocks of Manhattan with fire pumps, fifty-five miles of cast-iron pipes were used, plus additional lengths of 8-inch branches to feed individual hydrants.

The pumps used water from Croton rather than seawater. Efficiency tests found that freshwater was a better option.

The new pumping system had finished installation in 1909. This was the same year that the Fire Department received its first motorized Fire Apparatus (or - the fire trucks we know today). These new changes all began due to the Fire Departments' unification a decade earlier.