The break below the 45th Street viaduct spewed thousands of gallons of water and disrupted water flow to homes and businesses. Some even found brown water coming from the tap.
The water main was fixed at about 2 a.m. Wednesday, restoring water service to customers in the University District and University Village.
The 16-inch water main broke around 3:15 p.m. Tuesday and spewed thousand of gallons of water 25 feet into the air for nearly an hour. Overnight, crews cut out a 16-foot section of the pipe, spliced in a new piece and turned the water back on.
The next concern is brown water running into homes after the break stirred up rust and sediment inside the pipe.
"You can't take a chance with any of the water now because you don't know what it's been through, or if it's been contaminated - whether it's a different color or not," said one frustrated water customer.
But Seattle Public Utilities officials say the water is safe to drink despite the discoloration. They say the water should clear out on its own.
However, they also caution people not to wash laundry in the discolored water, as it may stain clothing.
Officials said the cast-iron pipe that broke is about 80 years old, but they still don't know what caused it to break.