* Which, I should mention, has a bit of a tradition of cheaping out on the construction. Why worry about the higher maintenance costs when that's going to be your successor's problem? Better to kick that can down the road and brag about how much taxpayer money you're "saving". Ahh, the beauty of the spoils system.
You bid out the construction to the cheapest contractor with strict penalties for late completion. But the same company then gets the contract for repair and maintenance for the next 20years!
Politicians were shocked when their brand new freeway closed for resurfacing within a month of opening.
"I'm shocked, shocked to find that gambling is going on here!"
A lot of the expensiveness of freeways also has to do with completely grade-separating it from other traffic. This route has several grade crossings at busy intersections.
Pay anything toward public/alternative transport and it's taxpayers money being lavished on subsidies. But spend a $Bn on a highway that just creates bigger traffic jams and it's vital infrastructure improvements.
Here they just voted themselves a big property tax hike to pay for a new $Bn freeway bridge after it became clear that the tolls wouldn't even cover the interest. But the express bus route that was going to use the bridge has been cut to save money.
It's also the argeument behind "cyclists don't pay toward the roads" when the majority of massively expensive road building is for stuff that cyclists can't use (freeways/tunnels) and they do pay for these in tax.