The break occurred around 4:30 a.m. along Cresson Street near Rector and Silverwood streets around Manayunk's "Pretzel Park".
According to officials, crews were working to repair two other main breaks in the city when the Manayunk break occurred, which impeded efforts to shut off the main quickly.
About 60 people were left without water when an 8-inch main broke.
The water department has been at the scene making repairs and checking the status of affected homes.
