I cannot remember a lot about the story except he is ex-military and when he leaves he goes to work building a highway and is capable of driving the heavy machinery. I think there is an ex-military female involved who can also drive the heavy machinery.
Are you sure it was a highway?
Anyway, a sort of similar basic plot is the story The Dirt Daubers so you may find that worth reading while you wait to ID the one you want.
https://storiesonline.net/s/13186/the-dirt-daubers
https://storiesonline.net/a/Catman
That sounds remarkably like another story, the guy is ex military and winds up as a farmer and highway commissioner, he drives/owns a bunch of heavy machinery too.
https://storiesonline.net/s/71089/recluse-and-ghost
