Because so many badgers are killed on the roads here in the UK too, the British highways people are increasingly providing tunnels under roads to provide safe passages for wildlife. As well as helping the local wildlife, this can also cut down the number of road accidents too.
In fact, one of the first British purpose-built tunnels was built for badgers as long ago as 1976. Under the M5 motorway (near Wellington in Somerset, England), the idea of the tunnel was that it should prevent them from being run over by traffic. The tunnel was specially located to intersect a badger path leading from the main sett to badgers feeding grounds.
At first this safe, underground route did not really seem to be working, as the badgers studiously avoided using it. Despite the fact that the tunnel was specially designed to save badgers' lives and to prevent accidents, and that it was filled with suitable bait, and badger smells (called musk), they still didn't use it.
It was only when the badger family had several cubs to rear (and needed better food supplies) that they officially opened the site. All in all, it took the badgers nearly three years to open their tunnel, although they quickly claimed the territory as their own, by placing latrines at either end.
That said, the tunnel has certainly saved the lives of badgers and prevented many potential accidents on a busy section of motorway - money very well spent.