CHAPEL HILL - The N.C. Department of Transportation will close South Columbia Street for only three months this summer – good news for local drivers and Chapel Hill Transit.

Bad news for neighbors – the construction crews may work on the road 24 hours a day.

The 0.8-mile project started in December and will add a center turn lane, bicycle lanes and sidewalks from Manning Drive to Purefoy Road.

Work crews originally planned to close South Columbia Street’s southbound lane April 1, routing traffic past UNC Hospitals on Manning Drive to N.C. 54 for six months.

Besides disrupting town, campus and hospital traffic, the work was expected to cost Chapel Hill Transit at least $850,000 to $1.5 million to reroute and adjust bus schedules. If the system added more buses and drivers to maintain existing service levels, the cost could have reached up to nearly $2 million, interim transit Director Brian Litchfield said.

The project had been delayed for years and local officials did not expect it to start so soon, Litchfield said . The system’s three partners – Carrboro, Chapel Hill and UNC – will have to find $350,000 to $500,000 of the additional cost this fiscal year, he said.

Although it will be a challenge, the remainder can be built into the 2013-14 budget, he said. The partners share responsibility for operations and costs. UNC picks up 60 percent of the local tab.

UNC Chancellor Holden Thorp wrote Transportation Secretary Eugene Conti Jr. last month to ask if the state could help relieve the financial burden.

Conti responded Jan. 3 that the work had been rescheduled for roughly mid-May to mid-August.

“I certainly understand your concerns, and I have requested Division Engineer Mike Mills to investigate the proposed construction schedule as listed in the current contract to determine if this could be revised to address the amount of time that the transit buses would be affected,” Conti wrote.

Mills worked with N.C. Board of Transportation member Mike Fox, DOT staff and Chapel Hill Engineering Services Manager Kumar Neppalli to reschedule the work for mid-May through mid-August when Chapel Hill Transit traditionally runs a reduced schedule.

In an email to local officials, UNC Associate Vice Chancellor for Campus Services Carolyn Elfland said DOT did not offer to help with the cost of rerouting Chapel Hill and Triangle transit systems.

However, the project’s shorter one-way phase would provide “a big financial savings for the transit system, and it’s about evenly split between two fiscal years,” she wrote in the email.