Crossing the Tokachi river is a suspension bridge which has very large girder areas. Here the lighting scheme emphasizes the massive vertical columns and suspension wires.
In order to enhance its shape, lighting poles on the bridge were used to illuminate the wires; we advised the architects to paint the wires gray, instead of the originally planned black, so that they would provide a good presence in daytime and a sharp profile at night.
Areas of the 68-meter-tall vertical columns visible to drivers and pedestrians on the bridge were flooded with light and the linearity of areas visible from the river banks and hills was highlighted. By combining area lighting and line lighting, a high-volumetric lighting design was achieved.
Linear lighting consists of two fiberglass cables, 10 centimeters apart, which transmit light along the surface. Maintenance is minimal requiring service in only one room at the bottom of the columns. Linear lighting was designed to change color according to the season: white in spring, blue in summer, green in fall, and pink in winter. Color is also varied to indicate time.
This bridge, which gives the appearance of two swans spreading their wings at night, is expected to become a town landmark, not only during the summer, when fireworks attract many visitors to the surrounding river banks, but during the long, severe winter as well.
