An unlikely sight in the verdant plains of Iowa, the High Trestle Trail Bridge in Des Moines Central River Valley, while a work of contemporary art and engineering, has historical roots. The installation, part of a conversion of an unused portion of Union Pacific Railroad track to an accessible hiking trail, was designed by the Des Moines-based RDG Dahlquist Art Studio/RDG Planning & Design. Snyder & Associates provided engineering and design services.
A series of rotated rectangular “portals” that span the 2,640-foot length of the bridge are references to the structural framing that braced the shafts of the coal mines that were once active in the area. Thirty-five feet tall, they are deliberately spaced and positioned to conjure the feeling of moving through time as well as space.
Channels in each of the 18 steel cribs over the water contain a total of 976 linear feet of Plexineon Blue series LED fixtures from iLight Technologies. The low-voltage design produces a bright, crisp, even glow that enhances—rather than dominates—the architecture and the experience of traversing the bridge, whether on foot or bicycle.