Bridge patrol

It's lights up on two new British bridges, one in London and one in Gateshead. Both have dramatic illumination schemes currently under design by the London and Edinburgh offices of Lighting Architects Group in the UK.

A glowing color-changing arch (above) will top the Baltic Millennium Bridge which spans the River Tyne between Gateshead and Newcastle in northeast England. Jonathan Speirs and Associates of Edinburgh, Scotland, has specified eight Irideon(TM) AR500s(TM) (in two groups of four) to accent a cleverly engineered structure that actually tips up to a height of 30m (99') above the water to allow tall ships to pass underneath. "A narrow beam limits the amount of light spill beyond the bridge," says Speirs, principal designer in the Edinburgh office. Two of the Irideon fixtures have frost filters, while the other six have ribbed lenses.

"It is a considered architectural use of color describing the entire arch," says Gavin Fraser, project designer for JSA Ltd. "There will be very long fade times with subtle and gradual changes to the appearance of the whole arch shape. People sitting in the nearby bars can watch the slow fades from the windows." A curved walkway and cycleway, both of which tip along with the bridge, have paired groups of LED recessed marker lights identifying deck edges. Beneath the cycle deck, structural ribs are accented with custom-designed "rib lights" using 10-degree PAR-20 metal-halide sources. The reflections of these ribs on the river will contrast with the reflection of the arch.

Red metal pistons that move hydraulically to open the bridge are housed in concrete caissons that sit like pontoons on the river. "Viewing rooms above these are like frameless glass boxes," says Fraser. "Theyhave concrete floors with recessed 8"-diameter glass circles which allow the blue light from the space below to filter up." The pistons will be lit as they move with white light from 10-degree metal-halide spots. This project is scheduled to be completed by December, in time for the millennium celebrations.

New pedestrian walkways have been added to the Hungerford Bridge (below), a London landmark that spans the River Thames from the Embankment Underground station to the South Bank near Festival Hall. Two new free-floating walkways hang on wires from high masts that lean away from this railway bridge; 70W metal-halide lamps will pick out the walkways and accent the angel-hair strands of wire that lead to the top of the masts, or center posts on the bridge.

"The light will graze down the cables and drift out," says Mark Major, principal designer for Speirs and Major in London. A custom lighting system for the handrail system features fluorescent fixtures with T5 slim white 15mm tubes, and the same lamps with blue filters as vertical accents. Philips MasterColor CDM lamps will throw warm white light onto the main pylons of the bridge.

"The new walkways provide two great views of the river--you can see Westminster and Parliament on one side and St. Paul's Cathedral and the City on the other," says Major. This is one London bridge that will not fall down, at least as far as its design elements are concerned.