A plan to add toll lanes to Georgia 400 in Fulton and Forsyth counties hit a major roadblock Thursday when the State Transportation Board rejected the only qualifying bid on the project.

Board members agreed with the findings of a board committee overseeing the bidding process that the bid submitted by the roadbuilding consortium MW 400 Partners was far in excess of the $1.7 billion the state Department of Transportation had budgeted for the work.

“This is a very upsetting point in the cycle,” said board member Kevin Abel, chairman of the board ‘s P3 (Public-Private Partnership) Committee. “[But] the project is not over. … It’s just going to be delayed.”

The Georgia 400 project is part of state plans to relieve traffic congestion by adding a series of toll lanes across metro Atlanta. Toll lanes are already in place along Interstate 75 in Cobb and Cherokee counties, I-75 south of Atlanta, and on I-85 in DeKalb and Gwinnett counties.

The plan for Georgia 400 calls for adding toll lanes to 16 miles of the north-south highway from the North Springs MARTA station in North Fulton north to McFarland Parkway in Forsyth County. Construction was scheduled to begin late next year and be completed in 2027.

The transportation board decided to put the work out to bid as a public-private partnership project, meaning the contractor would not only design, build and maintain the lanes but would also finance the construction. The contractor would recover its investment by collecting the toll revenue through a 35-year agreement with the DOT.

Meg Pirkle, the DOT’s chief engineer, told board members Thursday the agency conducted a “robust evaluation process” only to find just one bid fit the criteria the department had established for a successful bid. However, the bid was far above what the DOT had anticipated, she said.

Pirkle said she could not reveal the amount of the bid because MW 400 Partners has declared it a trade secret.

Pirkle said one factor in the higher-than-expected bid was that it came in May, a time when the price of construction materials was especially high due to supply-chain disruptions caused by the coronavirus pandemic.

The P3 Committee met earlier this week and recommended rejecting the bid and essentially starting over with the procurement process.

“We’re committed to seeing the project delivered,” Pirkle said. “But DOT [also] is committed to being good stewards of taxpayer dollars.”

Pirkle said it’s uncertain how long starting the procurement process over will delay the project.

Thursday’s decision also could delay other projects, notably plans to add toll lanes along the Top End of I-285.