Bridges aren't so simple

We fell in love with a property in the Catskills that has a one-acre lot next to a road and a six-acre lot across a small stream from the one-acre lot. I had fantasies of building a bridge so that we could place our home on the six-acre lot away from the road and above the flood plain. So I did a bit of research into building a bridge. The article Build Your Own Bridge on the Extreme How To website raised a lot of issues I did not consider. First, the number of regulatory agencies that would be involved, and second, the requirement that the bridge would need to support a fire engine.

I am still wondering if we could park on the one-acre lot and do a pedestrian footbridge and path up to the home on the six-acre lot. How would fire department and regulatory agency concerns impact that approach?