Utah County commissioners agreed Tuesday to sign a letter committing $65 million in sales-tax money to the Utah Department of Transportation's I-15 project.
The commissioners also will put $80 million toward widening Geneva Road, which will serve as an alternate route around the freeway. Construction is expected to begin in 2011.
The $2.6 billion, three-year I-15 project involves rebuilding the freeway between American Fork Main Street and the U.S. Highway 6 interchange in Spanish Fork.
Commissioner Steve White said he would prefer to see the funding done on a single bond instead of in phases as a way to ensure that the county's road projects are supported as well as the state highway construction.
"If we don't craft it carefully, we'll wind up with state roads but no local roads," White said.
Among the county's projects are building 4800 West from State Road 92 to State Street, and building a connector from Orem 2000 South to Center Street near Provo Municipal Airport.
Darrell Cook, Mountainland Association of Governments' executive director, said it was important at this point to get the issue on to UDOT's agenda so it could be incorporated into the State Transportation Improvement Plan.
He said developing alternate ways around the construction are an important part of the project. The goal is to have road networks on both the east and west sides of the freeway to help people get around the construction zone, he said.