Jbbb, I’m looking to do something similar but need tractor access. My thoughts were to use 3 telephone poles laid across the stream and decked with actual 2x6 rough cut lumber attached with ledger lock screws. My neighbor does something like this and drives his Chevy 1500 4wd across it. In your situation as a pedestrian bridge you might look at 2 telephone poles with pressure treated lumber decking attached with exterior deck screws. As far as moving the poles across the span, I would attach a snatch block to a tree further than you want the pole to go. Next tie the rope to the pole and run it through the pulley on the snatch block back to your vehicle alongside the pole you will be moving. Tie the rope to the vehicle, drive until the pole is in the desired location. You will probably need a couple of plastic 55 gallon drums for the pole to roll across the span to avoid putting it in the mud. Repeat process for second pole. After both poles are set drill a hole on the end of each pole and drive 4-6 foot of rebar in the 4 holes to anchor it. I have not tried this method yet but is an idea for your situation.
