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The need for the New River Gorge Bridge was first established in 1967, when the West Virginia Department of Highways contracted Michael Baker, Jr., Inc. to plan a route connecting the Oak Hill Expressway to US route 60. This was a distance of roughly 11 miles and stretched over rugged terrain consisting of mountains and the famous New River Gorge (Knudsen and Cain, 1978).
Just a short two years after initial surveying began, the proposed route was accepted and detailed planning on how the bridge would be built began.
Figure 1: Elevation view showing the bridge during preliminary planning.
(Knudsen and Cain, 1978).
Initial plans for the bridge left designers with a complex mess of questions lacking answers. The coal mines below the abutments still had their supports in place, and the slopes of the gorge were largely comprised of good quality sandstone. The decision was made to backfill the mines with a good quality coarse material, and to place the footings of the abutments roughly 60 feet up the slope from the mine entrances (Knudsen and Cain, 1978). This would place the abutments well above the coal deposits, which have a structure prone to failure if loaded wrong. Backfilling the mines with loose material ensured that there was extra support and allowed for drainage of water to prevent buildup of pressure that could cause landslides.
Engineers had an easy solution to the foundation, but the span would prove to be another issue. The proposed alignment stretched roughly 3,000 feet at an elevation of almost 900 feet (Bridge Walk, 2024). Various designs were considered, but none were satisfactory. A traditional cable-stay suspension bridge was the first to the table, but the tower height was deemed too high and costly to construct. A truss style bridge was next, but it was determined that too many piers would be needed, and thereby too costly. Finally, a massive steel archway bridge was suggested. This would be the largest bridge of its type in the world, requiring diligent design and plan work. Engineers had their solution and now needed to make it a reality (Knudsen and Cain, 1978). After several iterations of design, it was decided that an arch spanning 1,700 feet would straddle the bottom of the gorge, and large abutments would support the structure along the slopes.
Figure 2: The Bridge During Construction
(American Bridge Society, 2024).
Construction was planned in a few key phases. First and foremost, the non-arching portion was to be constructed on both sides of the gorge. Next, the arch was to be installed from both sides of the gorge, using a system of cables to hold the steel structure until it was joined in the middle. Once this was complete, the top deck was to be installed, and construction completed. During the entire process joints were being welded to ensure good connections and inspections were taking place to ensure no deflection was too high. The bridge was also the first of its kind to be closed in the center without and adjustable piece of steel, meaning a degree of precision was needed that had not been seen on a project of this scale. (Knudsen and Cain, 1978). While a simple plan in practice, the execution required a high degree of competency and ambition.
The project was awarded in a design-bid-build style. Brought to bid in 1973, construction began in May of 1974. The steelwork was finished in 1976, and by October of 1977, the bridge was open to travel (Knudsen and Cain, 1978). In only four short years the New River Gorge had transformed from a massive dividing obstacle to a scenic drive for locals who were now connected to the wider highway system in the region.
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