I have the best job in the world. Sometimes I get to work with a dedicated citizen and a group of willing volunteers to make something lasting and beautiful. (And useful!) Come and see this bridge in Petersburg, Alaska!
I acquired a grant to put in a bridge over a stream that was between a park and a mile long trail. The plan had been to install a glue-lam or log bridge across a 50 foot wide part of the stream. Building a log bridge is actually pretty easy if you have big timber to work with. But a citizen approached me and asked if he could design and guide the construction of a cantilever bridge with a small hut on it. Shortly afterward a Boy Scout was looking for an Eagle Scout project... and here is the process.
Step 1: Design
Working with local Forest Service engineers the designer took his vision for the project and ensured it was matched up with the right diameter and species of log. The engineer did calculations and accounted for humans and heavy snow weight to ensure that the volume of concrete and fill used for the cantilever would be adequate.
We were able to use a significant rock to perch the hut on and as the fulcrum point for the long cantilever. However, after calculations regarding the volume of water and high tide we had to raise and enlarge this point.
This bridge consists of two cantilevered wings meeting but not touching, in midstream. The concept is of a glorified log crossing. This bridge is not handicap accessible; in fact it is intended to bounce a bit, just like a log, before one crosses to the other side. The moss covered Troll Booth along the way can seat four people.
My vision is to encourage the pedestrian to pay attention and to enjoy a playful transition from one side of the creek to another. the cozy Troll Booth will make one want to pause, listen and watch. The view of the narrowing walkway ahead, and of the wings not touching, and the slight bounce of the bridge will alert ones' senses. As one steps onto the other wing, the crux is passed. Making the turn and reaching the stability of the other bank will complete the transition across the gateway.
Some people may not want to cross the bridge, because it requires paying attention, just like the trail ahead. And that's ok. There is a little here for everyone; it's more than just a bridge. Going part way and just sitting in the Troll Booth offers its' own rewards. As in life, it's a rough trail ahead, and we must pay attention as we cross each bridge along the way.