The Grand station on the Blue Line was closed temporarily due to flooding, but the CTA said late Monday that trains are now stopping there and the Halsted entrance has reopened. The main entrance remains closed as crews continue to clean up.
The water main broke near the busy intersection of Grand and Halsted. Water crews are on the scene trying to make repairs.
Motorists were forced to detour a busy six-way intersection in the River West neighborhood as water covered Halsted Street at Grand and Milwaukee. An iron eight inch main from 1930 apparently ruptured.
"When you have fluctuations in temperatures, stress on the cast iron, there's a thousand miles of cast iron lines and they're 100 years old," said Tom LaPorte, Chicago Water Department.
Two feet of water flooded the Blue Line Grand Avenue stop. Fortunately, water was not on the tracks, but the station is not usable.
Some nearby residents found their cars casualties of the flooding in a garage filled with water.
"We saw was the water rushing out flooded, and the first thing I thought was 'Oh, my car is in there!'" said Benjamin Bartz.
"We came down and there was about four feet of water in there already," said Mark O'Sullivan.
"It's devastating. We just bought a new car, and it's really sad," said Ellie O'Sullivan.
Crews are on the scene working to make repairs. They expect to have Halsted Street open by Tuesday morning.