Firefighters were dispatched to the scene at about 3:30 a.m. The broken 12-inch water main left approximately 30 cars standing in about 5 feet of water, according to fire officials.
The garage serves a three-story apartment complex in the 600 block of North Vermont Avenue between Melrose Avenue and Clinton Street.
There were no evacuations, and the cause of the break remains under investigation. Firefighters were pumping water out of the parking area and also provided sand and sandbags to affected residents.