It happened around 1 p.m. off Chemical Road near the Lowe's Home Improvement store in the Metroplex shopping center.
Aqua Pennsylvania said the hydrant is privately owned, but the company does provide water through an eight-inch service line that feeds the hydrant.
Video from Chopper 6 showed water shooting dozens of feet in the air.
Chopper 6 over major water main break in Plymouth Meeting, Pa.
Crews quickly shut off the valve, eliminating the stream of water.
The company said there was no impact to the water system. Repairs to the hydrant will need to be made by the owner, Aqua PA said.