Subsidies for roads

Very rarely does the opportunity arise where the massive subsidy to build roads is illustrated. You always here the argument that mass transit is too expensive, won't pay for itself, doesn't generate revenue,... This is a big topic in Dane County where the Mayor and the County Executive are for "trains" and many are for the status quo or maybe a few bigger roads. So, there is one of these roads, I'll admit it is screwed up, that needs up grading. The plan was just unveiled to build a little less than 2 miles of highway. The 17 year project will cost an estimated $343 million dollars. Gee the train we were talking about is only a couple of million. This is a road where in the middle of the day or on any weekend day there is not a traffic problem. $343 million to solve about a 5 hour problem. Has anyone looked at a cheaper alternative like routing the road across vacant land to the South? Or, how about eliminating the cross streets from county PD north to the beltline? Just the interchange at PD carries a $54 million price tag. Where are the teabag protesters on this one?