The break in a 16-inch water main on South County Line Road between Stagecoach Road and East Sixth Street caused part of the street to cave in. That stretch of road is closed until repairs have been made.
Water service has been restored to about 135 customers who were without it, but officials are advising affected residents to boil water used for at least three minutes before using for consumption or brushing teeth.
In Gary, residents in the 8900-9500 blocks of East 5th Street, East 6th Street and Sunrise Boulevard and the 400-700 blocks of South Warrick Street, South Wayne Street, South Wells Streets and South County Line Road are affected by the boil order.
In Portage, residents in the 5000-5200 blocks of E. 6th Street Stagecoach Road, Lincoln Street Harbor Road and Park Avenue and the 1700-1800 blocks of Pershing Street and Oakridge Drive are affected by the boil order.
The boil order is expected to be in effect until sometime Sunday, the water spokesman said.