A state bird inspires bridge lighting
In 2008, the mayor of Oklahoma City, Oklahoma, USA, announced an open competition to design a pedestrian bridge in the city's downtown. The design had to accomplish three goals: span a recently relocated highway, connect the north and south halves of a major city park, and serve as an Oklahoma City icon for citizens and visitors. Design consortium S-X-L (Spatial Experiments Lab) overcame a number of internationally renowned design firms with its winning design: the Oklahoma City Skydance Bridge.
Inspired by the scissor-tailed flycatcher, Oklahoma's state bird, this 119 m (390 ft) long, 9 m (30 ft) wide bridge was designed to evoke Oklahoma's sweeping prairie winds. The bridge's unique hybrid architecture consists of a soaring, vertically cantilevered tri-cord truss (split into sections known as the "wings," "legs," "hub," and "tail") and a simple span truss bridge. The construction of the wings was influenced by the flycatcher's lightweight bone structure, in which an outer "skin" is stretched around a hollow core. These wings also serve as the housing for more than 600 angled steel "feathers," which help give the structure its distinctive textured silhouette.
This unique form is lit nightly with a dynamic, color-changing LED lighting solution from Color Kinetics. 33 ColorReach Powercore floodlights and 16 ColorBlast Powercore wash lights were installed on custom steel mounting plates and evenly distributed throughout the structure's wings, legs, hub, and tail to illuminate the feathers with intense, saturated color. The lighting installation is controlled by a single iPlayer 3 digital controller, allowing city officials the flexibility to change color schemes and lighting effects with the push of a button.
Two key design objectives of the installation were to promote local industry and use sustainable solutions whenever possible. All installation and raw materials requirements were met by local steel fabricators, lighting contractors, and lighting suppliers, helping to support in-state jobs and reduce transportation costs. Durable construction materials containing a high percentage of recycled content — such as steel and glulam wood decking — were used to minimize the project's environmental impact and maximize its longevity.
The project's focus on durability, sustainability, and aesthetic elegance made the decision to choose a Color Kinetics lighting solution easy, said co-designers Hans Butzer and Stan Carroll of S-X-L. "We discovered quickly that the Color Kinetics series offered the best range of fixture types to help the design team achieve its vision," Butzer and Carroll said.
A truly green solution, the lighting system is predicted to have an energy cost of less than $2,000 annually.