Bridge: require no permits to build it. To emplace it is a different story, when fundamental changes to property are made, structures emplaced, one needs permits. Just like in your municipality: you need permission to make capital improvements; i.e. adding on to your house, building a garage.
Anyone stop to think that perhaps the bridge will be a PERMANENT fix to the area of the road that is prone to wash-outs? Put in some footings and secure it and you can have the mother of all spring floods and it will stay put.
Believe me, I have personal experience with seasonal road fixes and what a good storm can do. 15 years of it, actually. It's a lot more expensive in the long run to do repeated "quick fixes"....
I think as well, when one considers the trouble they are going to to build a bridge is suggestive of how long they plan to be around for this particular project.
But that's just my opinion, sorry it isn't a negative one....LOL