LANSING, Mich. (AP) Some companies that build highways in the state say they are laying off workers as a weak Michigan economy in part has left less money available to fund infrastructure projects.

Slagter Construction, a Grand Rapids-based road builder, has cut its work force to 66 from 102 in the past five years and plans to open a Florida office for the first time, President Brian Slagter said.

“Our Michigan business plan is nothing more than survival,” he told The Detroit News.

Due to dwindling revenue and the end of a highway bond program, state funding for highway construction and maintenance is expected to drop 24 percent over the next four years, to $1.23 billion in 2011 from $1.62 billion this year, according to the Michigan Department of Transportation.

“$1.2 billion is still pretty high, historically speaking, but it’s obviously not what they’re used to,” MDOT spokesman Bill Shreck said.

Chris Shea, president of highway striping company PK Contracting in Troy, said he’s considering opening an office in Florida. Some of his 100 to 150 employees are working only two days a week, he said.

“We have no intention of abandoning Michigan, but by the same token it’s just a monstrous concern around here about what people are going to do,” Shea said.