The project started with a rigging training involving a presentation of what can be achieved without machinery, but utilizing human labor and rigging techniques, rigging terminology, equipment, etc. After learning some of the theories of using rigging to use limited muscle power, and maximum brain power to move objects larger than could be moved using strength alone. We had a demonstration of how many pounds of pull strength the average person has. It was about equal to body weight. To show how rigging can increase that pull strength, a full size truck was attached to a tree with a wire rope, rope pulleys, and anchors, then I pulled it several inches just by pulling the center of the rope. The base camp was either 1/2 mile, or almost 2 miles walk through the forest from the bridge site, depending who you ask, and whether they guesstimated or actually measured with a GPS! It's a pleasant walk, and most walked it at least once. Additionally, the Forest Service had "improved" a dirt road into the site that was suitable for high clearance vehicles. There were enough trucks available to provide rides to and from the worksite daily.
Monkey Creek has an existing bridge crossing, but it was washed off its foundations during a high flow several years ago, and now sits at a precarious angle, wedged in a tree. Hikers are currently advised to wade the creek as long as the water is not high. The new bridge is 80' long, and will sit on top of the creek's banks, well clear of regular water levels, and about 1/4 mile downstream of the old bridge site. Part of the weeks work will involved dismantling the old bridge and rerouting the trail to the new crossing point.
The water level in the creek is currently very low. That's great news from the construction point of view, as we won't have to risk life and limb to struggle across the creek. Two large steps would easily get a hiker across the water, but rugged construction experts that we are, we placed a 12' 2 x 10 plank or two across the water to save us even having to get our boots wet! I have to admit, it did seem rather funny to me to be replacing this with an 80' bridge! However, construction was obviously planned for the time of year when water levels are lowest. I have not seen the creek in flood, and it does have fairly steep banks. I'm sure that at higher water levels there would be considerable risk to crossing due to the water depth. The area of the creek is a pleasant gently flowing backwater, with still, clear, tannin colored pools lined by white sand, gnarled twisted cypress knees, and shady pine forest. Reflections of blue skies on the brown water, and the occasional mushrooms just completed the picture. It's a beatuiful spot, and would have been very serene if there were not 30 construction workers immediately overhead and around.
Serenity was not too far though. About 1/4 mile downstream of the bridge site Monkey Creek flows into the Sopchoppy River. The ten minute walk down to the confluence was a popular lunchtime activity. If anything, the Sopchoppy seemed even darker tannin stained than Monkey Creek, almost to a deep red tea. The river turns a 90 degree bend immediately before the confluence. The river level is low right now, giving access to the flat white sand edges of the river, below the steep 10' - 15' banks. This minature gorge is filled with the exposed roots and limbs of Cypress trees that are evidence of scouring when the water is higher.
About 1/4 mile upstream of the bridge site the trail crosses the creek at the site or the old bridge which was washed off it's support several years ago in a flood and has been wedged up against a tree since. A small crew spent a day dismantling the old bridge and relocating the used timbers up to the new bridge site. Some of the old material will be used temporarily during the construction process, some will be used for construction of a ramp up onto the new bridge, and the remainder will be removed at the end of the project. The Florida Trail will be re-routed to the new bridge location when it is completed. At the construction site, on the first day, was organized chaos! The ground was strewn with piles of the bridge kit pieces that will eventually become the 80’ free spanning bridge. The pieces are made of a light-weight fiberglass composite material, precut and predrilled. Lightweight is a relative term, many of the pieces are large and/or long, and flexible. They require several bodies to move them. Our job is to take the piles of pieces, the instructions, and a couple of boxes of bolts and joints and make a bridge out of it all.
The plan was: Assemble the two 80' side trusses first, and utilize the rigging training to hoist each side truss over the river with a highline system, set them into place onto the abutments that have already been built by the trail crew, then add the extra side supports and the foot tread between. Sounds easy enough!
Except no-one realy knew what they were doing, or supposed to be doing. We swarmed the truss pieces, grabbing uprights, joints, bolts, washer and nuts and began putting everything together. Everyone was anxious to do something, and the way we were working you'd think we thought we could get it built in a day. As the afternoon wore on, those smart enough to take a break sat on the abutment on the far side of the creek, looking longingly like they were expecting a bridge to come over any moment.
As the bulk of the crew worked on the bridge pieces, work was also progressing on the other element of the construction: Creating a rigging system to move the partially completed 80' long, heavy but very flexible trusses down the bank and across the creek. An essential part of that system is the spar, a tall strong pole which will bear the weight of the bridge. For this job, two spars, one on each side of the creek, and a sky line strung between. Suitable tall straight pine trees are identified, cut down, branches removed, and then the bark is shaved to allow the tree to be checked for cracks, etc, and to make a smoother surface for the straps that will hold winches, cables, etc. The end product looks like a telphone pole. A hole is then dug at the location the spar will be raised, and ropes, cables, and winches used to lift it into place. 
Meanwhile, the piles of bridge pieces dwindle as the side trusses take shape. First one side, then the other, the kit is bolted together, tightened, torqued, jacked up and cambered. Finally we had two complete trusses ready to move. The trusses are temporarily supported upright with braces and ropes. The permanent side supports will not be added until after the bridge is in place. The 80' trusses are solid and stable while they are supported upright, but flex like a wet noodle when moved unsupported. An additional issue that was not anticipated, is that the uprights of the bridge extend about 6" below the lower support beam. This means that the truss will not be able to slide along the ground, but will have to be supported so the uprights do not dig into the ground, then moved along on roller logs until the truss is far enough forward along the sky line to be lifted completely off the ground. A final check is made of the spar poles, guy lines checked and tightened, and we're ready to lift the bridge. This is the most complex part of the construction, and the most dangerous. Once the winch is tightened and bearing the weight of part, and then all of the truss, care must be taken at each of the wire ropes. They will all be under differing stress depending on where the weight is placed at any given moment. We are all given constant safety briefings and warnings. People are stationed at each pole and guy wire, and others are positioned to brace the bridge with ropes to prevent lateral movement as the bridge moves forward. ...and we're off! At first the leading edge is lifted off the ground, and the rear is rolled forward inches or feet at a time. Once the front half of the first truss is "flying". With a brakeman in the rear to prevent the entire truss from flying down the line out of control, the rear is also lifted up on the skyline and the entire truss is airborne. A crew on the far side pulls, the brakeman releases slowly, and the truss inches it's way to the other side of the creek.
As the truss progressed down into the creek, those 6' lower extensions of the uprights became an issue again, and additional bracing, log rolling, and a little manual jacking and lifting was needed to complete the journey over the creek. But the pulling contined, and the creek was soon crossed, and both ends of the truss steered to their abutments. The first truss was positioned, bolted, and braced into position.
Now the process just has to be repeated for the second truss. Before starting the second movement the crew practiced on the winches and ropes by moving the wooden footing planks cross the creek on the skyline. Unfortunately, the great weather we have had so far for construction failed us at this stage. Just as the second truss was attached to the skyline and began it's ariel journey a storm was approaching. Severe weather was reported west of us. High winds and tornadoes were possible. Debris and small branches were already falling from the trees above us, and the Forest Service declared the worksite was to be cleared. We secured the half moved truss as tight as possible, cleared up the worksite to remove or secure and potentail flying objects, and returned to camp. And that was where my first F-Troop project had to end. I was supposed to leave the next day anyway, but with the threat of severe weather, the sleepless night that would ensue trying to sleep in a windblown tent, and especially the idea of having to pack up a wet tent in the morning, I decided to pack up and head for home tonight instead. I would have loved to stay another day, especially if it meant seeing the bridge completed, but I have a hiking trip planned starting early Saturday morning. I doubt at this stage that I would see the bridge completed before Friday afternoon, which would be the very latest I could leave to do the 400 mile drive down to the start point, and get my laundry done too.
But that's OK. I now have an excuse to return soon to this trail section to hike it and cross the newly completed bridge myself. I won't have the experience or the pictures of the final stages of completion, but I know which bolts I put in myself, and I'll be able to come visit them and still feel the accomplishment of being a small part of the construction.
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