Cheryl Fritze, the unofficial leader of Okemos residents opposed to the construction project, called the vote "more than surprising, shocking."
It puts the widening of Okemos Road on pace after a long delay over public input in the project.
The road commission voted to widen the road to 5 lanes, digging into the east side. The project will cost about $3 million. They say its designed to decrease rear-end accidents and ease traffic.
Residents say it will make speeds faster and threaten safety in their neighborhoods. They complained primarily about the lack of public input into the design.
Last month, Fritze won a lawsuit against the commission. A judge said the commission violated open meetings law. Thursday night's meeting was called to meet the regulations of that judgement and allow the necessary public input.
Fritze and some 75 neighbors expressed concerns that the commission treated the meeting as a formality.
One of the three commissioners voted no. The two others carried the vote.
Ingham County Road Commission spokesman Gary Naeyaert said, "All of the concerns were considered. It's simply that the commission didn't agree with all the concerns."
Ingham County Commission Deb Nolan, who is from the portion of Meridian Township that would be home to the construction project, headed up an effort by the county commission to stop the vote. She and her collegues sent a letter to the road commission, warning them not to vote. They talked about asking two of the commissioners to step down, but after consulting an attorney, say that's not feasible.
Fritze says she and her neighbors will consult an attorney to determine what to do next on Friday.