Chroma Streams: Tide & Traffic is a site-specific, integrated artwork for the highly trafficked Kingston Bridge in Glasglow, Scotland. The installation was one of many commissioned by the Glasgow City Council as part of its municipal lighting strategy. The artist’s challenge lay in addressing the bridge’s highly visible but aesthetically unappealing structural materials. The project’s premise is focused on the two tides represented by the river and the traffic above it, and the bridge’s underside and its riverine reflection were selected as the “canvas” for the illumination.
Two monumental concrete arcs make up the bridge. Directly under the bridge, two sleek, stainless-steel standards (approximately 6 meters high) comprise the installation’s daytime sculptural elements and direct light in a number of ways to illuminate and give resonance to the bridge’s overlooked surfaces.
Chroma Streams is a syntactical structure into which chance patterns of traffic and the predictable tidal cycles of the River Clyde are visually presented and interpreted through a changing montage of colored light. A linear color pattern based on the cool end of the spectrum—ranging from light green to indigo—represents the four distinct cycles of the river’s flow. Traffic engineers graded traffic flow above the bridge into several modes based on speed and volume, and these flows are represented in a palette of six colors on the warm end of the spectrum, from a clear yellow to a strong red/pink. Via sensors installed on streetlight standards, real-time traffic flow data are transmitted to the lighting apparatus and downloaded into a computer program. This programming allows for 144 sequences of discrete color mixes.
The challenging budget of $400,000 was stretched by significantly involving city-employed traffic engineers in the project and by using a universal tidal program to determine the light flows on the underside of the bridge. The minimal quantity of lighting fixtures (12) for the huge bridge canvas was determined with sustainabiliy and budget in mind.
As traffic pours into and out of the Glasgow city center, an interactive lighting spectacle feeds back nighttime rhythms of city circulation to onlookers and passersby. Relating traffic and tide enables spectators to contemplate the chance interrelationships between nature and manmade.
“A night rainbow. Magic. Glasgow sings a colorful opera from the bridge and it also makes the river dance.”
“What makes this light performance particularly special is that it blends the pace of the earth, in the form of the tide, with the data from a city, in the form of bridge traffic, creating an interface where the natural and the mechanical meet.”
“This project takes the forgotten underside of an urban infrastructure and lyrically animates the structure, the water, and the cityscape. As a simple lighting scheme alone, it would be delightful. But when activated by the movement of traffic and water, the bridge dances to the music of an unseen orchestra.”
Leni Schwendinger (artist), Chuck Cameron (project manager)
James Young Ltd. Northern Light (installation); Mott MacDonald (structural engineers); Normand & Thomson Ltd. (stainless steel light standards); Glasgow Development and Regeneration Services, Glasgow Land and Environmental Services (owner agencies)