In the wake of the tragic bridge collapse in Minneapolis on August 1, we've received numerous questions about the structural capacity and condition of the High Line. Is the High Line structurally sound? Is the High Line susceptible to a structural failure similar to that of the bridge in Minneapolis?
The High Line is structurally sound, and it is different from the Minneapolis bridge in a number of ways. First of all, in terms of its structural design, the High Line employs a much simpler structural system, using single-span beams and girders on columns, spanning short distances, as opposed to a more complex "truss-deck" bridge designed for larger spans. This means that the loads for any given area on the High Line are transferred immediately to the underlying beams, and to the ground through the nearest column. Secondly, the High Line was designed for a much greater loads – by a factor of 20 – than what is necessary for its future use as a pedestrian promenade. Thirdly, under the guidance of noted structural engineers Robert Silman & Associates, the High Line has just undergone a comprehensive inspection and repair program as part of its transformation into a park. The engineers' inspection has revealed that the High Line structure, in general, is in remarkably good condition. At specific locations, however, repair work includes removal and replacement of small areas of rusted steel, and replacement of underperforming rivet connections. In addition, the concrete slab has been tested and, wherever necessary, patched or replaced in order to insure its integrity. Finally, complete sandblasting and repainting of the structure will protect the condition of the steel over the long term.
Safety on the High Line is our top priority. Over time, the High Line structure will be inspected periodically and repaired, as necessary, in order to ensure that there are no risks to the public.