GARDINER -- The southbound lanes of Interstate 295 from Gardiner to Topsham opened Saturday evening -- 20 days ahead of schedule.

That 18-mile stretch of road has been closed since mid-June so construction crews could repave the interstate.

The Maine Department of Transportation officials had announced on Friday that the lanes may open this morning, weather permitting.

But DOT Commissioner David A. Cole gave the go-ahead for the lanes to officially open at 6:10 p.m. Saturday.

He said the project was completed without any major incidents and traffic remained smooth on the two designated detours: U.S. Route 201 and Interstate 95.

Everyone involved including Pike Industry, subcontractors and DOT employees made the project a success, he said.

"We had bonuses built into the contract to get it done early," Cole said Saturday. "They worked long hours, weekends and holidays because we knew the public was depending on us to get in and get out of this corridor and do the job right."

Pike Industries had incentives in its $28.5 million contract that paid the company a bonus of up to $2 million for finishing before the Aug. 30 deadline.

Cole said the public's cooperation helped DOT deliver a project that could have taken three years and had a lot more disruption and potential safety issues. Closing the lanes and rerouting traffic was a strategy used by DOT to repair Memorial Bridge in Augusta a few years ago, he said. The bridge was closed and traffic sent through downtown Augusta. He said that project was completed within three months instead of nine months.

Accelerating construction projects saves money, is less disruptive to a community and safer, he said.

"In an era where we have shrinking resources, by working with the communities and impacted parties to accelerate projects we can get it done cheaper, faster and safer and it's good for communities because more cut down on time quicker were out and not interrupting people's daily lives," Cole said.

Cole said most travelers used I-95, the Maine Turnpike, as an alternate route. Officials predicted about a 30 percent traffic diversion to the turnpike, but in reality, almost 50 percent of the motorists chose that route, Cole said.

Transportation officials said that fact helped contribute to "the safest summer since 2003 on U.S. Route 201."

The new road is expected to last more than 20 years. Despite a wet construction season, workers have laid 181,000 tons of asphalt, installed seven miles of guardrail and rebuilt five bridges since June 15.

"We really appreciate the cooperation of the towns, first responders and law enforcement," Cole said. "I can't thank the public enough. It's been good for DOT reaching our missions. We don't build roads in isolation. We do it for a reason. We do it to serve the communities. It's good for everyone to get this open."

Mechele Cooper -- 623-3811, Ext. 408

mcooper@centralmaine.com