Wednesday, September 14, 2011

muddy rubber boots

muddy rubber boots
wait for construction workers
to get back to work

Our truck kicks up white dust on the gravel of West Ravine Road. We keep passing big red and white signs, Road Closed. Finally, we see a smaller sign, Hruska's Campground Open. When we arrive at the campground, it's clear why the road is closed. A pair of concrete T-columns rise up from the water on either side of the river, twice as high as the old iron truss bridge. The enormous pillars, like the ones on a four-lane interstate overpass, look totally out of place in this picturesque backwoods area of northeast Iowa. In the morning we are awakened by the sound of a semi-truck with a long cargo bed dumping a load of large limestone rocks. We walk through the early morning mist to watch the activity. Two men unroll and slice off a length of black groundcloth, then carry it over to the sloping bank to lay under the rock backwall. One man in an orange digger scoops up a load of rock and dumps it on top of the groundcloth. A driller on the other side of the river blasts through the rock, preparing for the next set of footings. 

The old bridge rests incongruously in a field next to the crane that lifted it from the place where it had stood for 122 years. The Upper Bluffton Bridge was built in 1888 by the Wrought Iron Bridge Company of Canton, Ohio, which fabricated the parts and shipped them by train and wagon to the site on the Upper Iowa River in Winneshiek County, where it was erected by local contractors. The Upper Bluffton represented a new type of bridge construction, the Pratt truss, which used diagonal bracings slanting downwards towards the center of the bridge, allowing the structure to withstand pressure towards the middle. However, it was also one of the last of its kind. By the 1890s, steel was used exclusively for bridge construction because of the numerous advantages it had over iron structures. The Upper Bluffton Bridge, built for horse-drawn carriages, carried a 3-ton weight limit and a 9-foot vertical clearance limit. But with the advent of heavier motorized vehicles, this became a handicap. 

Despite the posted restrictions, many drivers chose to ignore the signs and cross the bridge anyway. The man who comes to shuttle us to our canoe put-in upriver tells us, "Not many people know how high 9 feet is. They were scraping the AC units off the tops of their supersize RVs." Fearing that the bridge might collapse, as had happened to a similar structure in Missouri, county engineers decided to replace it rather than repair it and reroute heavier traffic. And so another unique and beautiful structure has gone by the wayside. Perhaps it will be left in the field next to the new bridge, with a little plaque explaining its historical significance, for those who take the time to stop.

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