Theatrical lights celebrate the holidays on major bridges
When the crew members of Carr & Duff, Inc., celebrated the Fourth of July four years ago, they converged on the banks of the Delaware. From there, they had a view of their latest accomplishment, a theatrical light show on the Benjamin Franklin Bridge.
Carr & Duff of Philadelphia has become the electrical contractor most familiar with this bridge that sends power across the Delaware River and also boasts a programmable, dramatic light program.
This two-mile bridge is one of the early suspension bridges, linking Camden, N.J., and Philadelphia. Built in 1926, it existed for years without lighting. In 1986, Philadelphia architecture firm Venturi, Scott Brown installed customer-designed metal-halide fixtures with beams that were computer controlled, showcasing the bridge cables with white light. The lights had their own dramatic appeal—they were programmed to brighten and then dim with the passage of trains.
As the decades passed, designers began to consider doing more with the lighting. The existing white lights illuminated the cables but not the bridge structure itself.
In 1999, the Delaware River Port Authority (DRPA) began seeking a better, more dramatic lighting experience. They were hoping for something that would make an impression around the time of the 2000 Republican National Convention. The new lights would be multicolored and would illuminate not only the cables but the approaches, portals, roadways, pedestrian walkways and suspension towers. They chose lighting design consultant Grenald Waldron Associates with a six-month deadline to get the work done.
The project started in early March with a targeted completion before Philadelphia’s Republican convention in August. The old system was to stay intact, but would be enhanced by the light additions. Designers intended the bridge lighting system to showcase the graceful design of the bridge, giving the structure the appearance of floating above the river, while its lights reflected off the water.
With the short deadline, workers needed to install the lighting during long hours and weekends, without interfering with the busy traffic flow between New Jersey and Pennsylvania. The rail line that crosses the bridge needed considerable improvements to its lighting. The biggest challenge for Carr & Duff was installing the railroad lighting, which required that electricians work around the movement of railway traffic.
The Northeast weather was another challenge. Engineers wanted to be certain the lighting equipment could withstand the nearly constant traffic-fueled vibration and the extreme weather conditions of the Northeast. Extreme summer heat, as well as ice storms in the winter, posed hazards to lighting fixtures and cables.
Clashing with the actual color of the bridge was another early problem. The lights did not complement the original dark blue color of the bridge. The port authority had the bridge painted in three lighter shades to determine the best combination with the lighting.
Steve Dietrich, project manager for Carr & Duff, was quite familiar with the Benjamin Franklin Bridge. His crew had extended six four-inch conduits across the bridge for level-three communication in recent years and provided radio communication for DRPA and the PATCO Speedline (the city transit system) that crossed the river at the bridge. Because of this, the crew was not only familiar with the bridge, but most were already trained to work on it, saving the port authority the time needed to train them.
“We were very familiar with working on the bridge and the people involved,” Dietrich said. “[We] had a good working relationship.”
The men used scissors lifts for most of their work. The port authority provided three moveable platforms and a lift underneath the bridge, from which conduits were run. The workers used their own lifts to install the pedestrian walkways lights. They also used their own high lifts to provide lighting at the east- and west-side approaches to the bridge. When the men needed to access the towers, they used ladders and platforms that were already built into the bridge.
Carr & Duff removed existing antique brass fixtures that had been mounted on stone anchorages at the bridge-deck and the street levels. After the fixtures were removed, they were sent to a local company that stripped the paint and restored them. “We reinstalled the fixtures in their original locations,” Dietrich said. The reinstallations required boom trucks and slings.
Ornamental poles and lighting were installed on pedestrian walkways into the existing handrail support steel. On these walkways, the original lighting was inadequate, offering too few fixtures, too far apart. Carr & Duff added fixtures and long-life 70W metal-halide lamps, allowing pedestrians a continuous light source across the two-mile span.
The conduits were run on the outside of the handrails. Because the bridge’s existing paint contained lead, the men had to remove the paint from all areas where they were drilling anchor holes. A painting contractor on-site scraped and disposed of the paint for Carr & Duff.
The 25W Color Kinetics LED lights were mounted on the bridge’s underside deck along both sides. The men accessed these lights with three moveable platforms that stretched across the bridge’s width from the roadway level. Dietrich’s crew connected the lights to a controller mounted under the bridge, then to a communications cable and onto a DMX lighting control panel. The panels were then connected to the computer system in the bridge maintenance offices by fiber optic cabling.
At the top of the bridge towers, just below the beacon lights, Carr & Duff’s workers installed accent light fixtures mounted in a glass window. These Hi-End lights produce different colors and effects using software controls.
They ran an Ocala Inc. rigid steel conduit up to the bridge with a blue PVC coating.
To accomplish all this and still stay on schedule, the men worked six days a week, generally 10 hours a day. “Most of our work was under the road deck,” Dietrich said, using the roll-along steel platforms under the bridge. In addition, they used a water safety service, which maintained a position under the bridge for rescues in case a worker fell.
Ultimately, the job was done in time for the Fourth of July, allowing the Port Authority to show off its new lighting in style.
Horizon 2000 software allows personnel to program lighting programs that are appropriate for an event. Personnel also can shut down the railroad lighting effects at the time of an event. Port authority personnel, with HTML user interface, can program from their own PCs at an office or home. Most often, programming is done from a control room in Camden.
Other holidays have been celebrated with holiday bridge lighting, including Hanukkah, Valentine’s Day and Christmas. In fact, more than 2,000 cues are available for 25 sequences and shows. On a daily basis, there are two main shows. At the top of the hour, the bridge provides a colorful five-minute show, and at the bottom of the hour, a shorter program.
Increasingly, bridges like the Ben Franklin are featuring theatrical and dramatic lighting, but these also must coordinate with environmental demands. Often permission from the U.S. and state fish and wildlife offices and the National Marine Fisheries Service is required to determine how the lighting will affect wildlife. Bridge designers must be prepared to produce evidence that the lights will have no negative effect on protected birds or fish. Peregrine falcons, as well as salmon and trout, are some species that could be affected by the lighting.
Another issue is safety: water, roadway and air-traffic safety. Lighting can affect visibility for pilots flying over or near the bridge, drivers crossing it, and boaters cruising or working below.
Despite these issues, light installation in some ways has become easier. New bracket designs have simplified access for maintenance and color changes, and lights require less maintenance than in previous decades.
Two years ago in Pittsburgh, a similar accomplishment brought colorful lighting to the city. The Roberto Clemente Bridge, linking Sixth Street with PNC Park, was first illuminated in November 2002.
Lighting installation began in August by Sargent Electric Company of Pittsburgh. The lights include five fixture types, most covered with white globes and accented by blue lamps. Four portal light fixtures, two on each end of the bridge, illuminate the area. Each fixture contains five large white globes 13 feet above a stone pier. A total of 32 fixtures light up each side of the bridge.
Seventy-four smaller blue lamps outline the top of the bridge from the upper towers. Floodlights further highlight vertical cables and towers, while the light spills onto neighboring piers.
For contractors, there are few jobs that showcase their work with as much drama on a daily basis. EC
SWEDBERG is a freelance writer based in western Washington. She can be reached at firstname.lastname@example.org.