A 16-inch water main broke on the north side of Butte High School at 5:15 p.m. Wednesday, sending a fast stream of water into the Commons section of the building.
By 6:15 p.m., Butte-Silver Bow water crews shut down two key valves, stopping the leak, said Public Works Director Dave Schultz.
The water entered the Commons area through the north-facing doors, flowed over the floor and exited the south entrance doors, said Jed Hoopes, district facilities director.
About two inches of water gushed over tile in the Commons area, which includes a hallway, a new athletic director conference room and bookkeeping offices. A chemistry classroom was also flooded.
However, the new conference room and offices have carpeting that will have to be cleaned, said Hoopes.
Crews also dealt with sand, ice and slush — in single-digit temperatures.
Shultz said sand washed up against the north wall of the Annex on the east side of the building and on Nevada Street, but city crews worked to remove it late Wednesday.
Slush and ice also created problems on the north Wyoming Street side, so that gate will be closed Thursday.
“It’s a tough time of year to have a leak,” said Schultz. “We’ve got a lot of crews out, so we can deal with the problem.”
The source of the break, the 16-inch water main, runs adjacent to the sidewalk that runs north-south. The water flowed directly from under the sidewalk next to the Naranche Stadium restrooms facing east.
Schultz said he won’t know what caused the leak until his crews dig up the main. At press time, Hoopes said that cleanup crews worked removing water from the floors.
Superintendent Judy Jonart said she expected the floors passable for normal use on Thursday.
Ned Ellingwood, chief engineer at the school, stood at the source of the break soon after it happened.
“This is a bad night for this,” said Ellingwood.
Temperatures were expected to drop to 4 below zero Wednesday night.
Standing water slowed traffic as it flowed over Wyoming Street. Part of the new parking lot was a messy mixture of free-standing snow and flowing water — as the sun set.
The break is not part of the recent parking lot upgrades, said Ellingwood. The upgrades, completed last summer and fixed in October, are on the south side of the building.
No damage estimates were available at press time.