Work on a broken sewer line will close Airport Road south of William Street beginning at 9 a.m. today.
A Carson City Public Works crew will work around the clock to repair the 12-inch line, which broke on Saturday.
Public Works Operations Manager Tom Hoffert said the line is 16 feet below the street and will take up to 72 hours to excavate and repair.
The break was discovered Saturday when sewage backed up in eastern Carson City.
"We had some backups to the east of Highway 50 and Airport," Hoffert said. "We had to get all of them fixed Saturday morning to mid-afternoon."
Hoffert said the break has been bypassed, but it can't be repaired from within the line.
"If we weren't bypassing the break, sewage would still be backing up," he said.
Hoffert said hydrogen sulfide gas produced by raw sewage deteriorated the concrete pipe to the point where soil collapsed it and filled the line.
The break cannot be detected from the surface, and the pipe is at such a depth that Hoffert said he doubted the break could have been triggered from above.
"There's not much weight-wise that could have caused this from the surface," he said.
City utility workers and public works employees will try to complete the repair with a minimum of disruption of business.
"We will work around the clock until we get it taken care of," he said. "We think we can handle this job."
The city will close 250 feet of Airport Road from Highway 50 East south toward Woodside.
Because of the depth of the hole needed to fix the line, crews will have use shoring as they dig.
"The city will make every effort to minimize impacts to local businesses and apologizes for any inconveniences this closure may cause," Hoffert said.
