An early feat of suspension engineering, the Benjamin Franklin Bridge spans the Delaware River, linking Philadelphia, PA, and Camden, NJ. Completed in 1926, this septuagenarian now sparkles anew with a colorful, animated lighting design by Grenald Waldron Associates in Narberth, PA, combining 72 High End Systems EC-1™ architectural fixtures and 384 C-200 WaterColor LED fixtures by Color Kinetics.
A precursor to the Golden Gate Bridge, the two-mile-long Benjamin Franklin Bridge (which has a one-mile span) was last lit by the Philadelphia architecture firm of Venturi, Scott Brown in 1986. They used custom-designed, computer-controlled narrow-beam metal-halide fixtures to highlight the catenary cables on the bridge with twinkling white light.
“There was a competition 20 years ago, and they won,” recalls principal designer Raymond Grenald, who had been trying for years to interest various city agencies in lighting the bridge, along with other notable places in Philadelphia, from the stately Art Museum to the outdoor stalls of the Italian market, by way of City Hall, 30th Street Station, Independence Hall, and Boathouse Row on the shores of the Schuylkill River (which Grenald Waldron actually did light 20 years ago). “By relighting the bridge we created more of a sense of place,” he says. “The bridge looks longer and more dominant than in the past, and it creates a new icon on the Delaware River.
“The Venturi design lit the cables, but not the bridge structure,” notes Grenald. An interesting aside, however, is the fact that the 1986 lighting design used a custom control system designed by George Izenour, theatre consultant and father of Steve Izenour, a principal at Venturi, Scott Brown. “The lights dimmed then brightened to follow the train across the bridge,” Grenald points out. “The lights also responded to music.”
In the fall of 1999, a team consisting of Grenald Waldron Associates (lighting design), Pennoni Associates (engineering), and Joseph Jingoli & Son (construction) was asked by the Delaware River Port Authority to create a new, dynamic look for the bridge. “They wanted it finished in time for a memorable July 4th celebration and for the Republican National Convention in the summer of 2000,” says Grenald.
Instead of just the cables, the entire structure would be addressed this time, including the approaches, portals, roadway, pedestrian walkways, anchorages for the suspension cables, suspension towers, and catenary and suspension cables. With just six months from start to finish, work had to move quickly to complete the project on time.
NEW LAMPS FOR OLD
The decision was made to design a cohesive lighting package for the bridge, adding new elements while keeping the existing lighting intact. “They always knew they wanted to keep the existing lighting,” says Grenald, who agreed that the old system definitely needed updating. “So we kept it, linking it to our system.”
This bridge is particularly graceful, and the lighting designers wanted to show off its full length, as well as restore the sense of its architecture floating above the water, casting beautiful reflections on the river. The lighting was also carried to the top of the 382'-tall (116m) towers to accent the height of these soaring structures. In addition to the new fixtures, the old ones were cleaned and given new lamps. “We were interested in using long-life lamps but it would have been too costly to use them in every fixture,” notes Grenald, who did opt for 100,000-hour lamps in beacons at the tops of the towers, positions hard to reach for frequent maintenance.
The choice of 25W Color Kinetics LED fixtures was “a natural progression in the design process,” says Daniel E. Edenbaum, the project designer at Grenald Waldron. He was looking for a solution to effectively delineate the stiffening truss that runs below the roadway, and add kinetic patterns of light that would follow the movement of the trains and cars that cross the bridge.
Grenald Waldron invited representatives from Boston-based Color Kinetics to talk about the project, and as Edenbaum admits, “I was impressed and intrigued by their outdoor fixtures and then talked the rest of the team into using them.” The fixtures met the design goals of changeable color, long life, low maintenance, and a kinetic quality to “make it a bigger show, and give a liveliness to the bridge,” notes Edenbaum. Although the bright color-changing LEDs cannot be seen by cars driving across the bridge, they are visible from numerous vantage points for several miles along both sides of the river.
CHALLENGES ALONG THE WAY
Some of the optimum lighting positions had to be abandoned due to difficulty in maintaining them. There were also enormous time constraints and various obstructions. “We also had to program without stopping the train that runs across the bridge,” notes Edenbaum. They couldn't work in the train tracks without having someone flag the train to stop. Luckily, there was access to the stiffening truss from below the bridge on moving maintenance platforms. “This is an active bridge and during rush hour all the lanes must be open. There was a lot of juggling to get the project finished on time.”
Other challenges to the equipment include vibration and extreme weather conditions, with high temperatures in the summer and ice falling from the suspension cables onto the lighting fixtures in the winter. “The 100,000-hour LEDs seem resistant to both,” says Edenbaum. “Color Kinetics measured the g forces on the bridge and made sure the fixtures and power supplies would last.”
Mock-ups were done to check various colors against the dark blue painted background of the bridge itself. “They were in the process of repainting the bridge,” points out Sandra M. Stashik, project manager for Grenald Waldron. “Some of the lighting would have looked terrible with the color they picked, so we asked them to go back to a lighter shade. In fact, they painted segments of the bridge with three different colors and we did demos with the High End fixtures so we could pick the most effective blue paint and color filter combinations, in particular the red, which is the most difficult to achieve against a blue background. The mock-ups were done in the dead of winter and it was cold out there.”
Another complication during the mock-ups included the fact that the Port Authority building — the vantage point for the client to see the mock-up — has tinted windows, so the light didn't look its best. “We had to convince them to go outside to see it,” says Stashik. The power for the lighting comes from the anchorages and towers, with aproximately 10 miles of conduit and 50 miles of cable to light the bridge.
COLOR ON THE HORIZON
Edenbaum designed the various light shows, which run after dark, working with Brian Evans, the programmer for Rosco/ET, using Horizon software with WYSIWYG. There are two main shows: a five-minute show at the top of the hour and a two-minute show at half-past. “The top of the hour is more about color,” says Edenbaum, “while the bottom show is more about movement and the dynamics of the bridge.”
The LED colors and movement are programmed in certain patterns such as the “chime,” which starts at the center of the span and moves toward the shore. There is also the “big bang,” from the shores to the center of the span and back to the shores, and the “train chase.” The 72 High End Systems EC-1 fixtures add to the movement, with color changes every 40 seconds during the top-of-the-hour show, and blue and white swirls around the towers in the bottom-of-the-hour show, while the LEDs sparkle in blue and white, complimenting the blue bridge.
“One of the most impressive system design challenges I was able to fulfill was the ability of the lighting system to make logical ‘decisions’ based on time of day, time of year, as well as events currently running,” says Evans. The “logic” of the decisions was dictated by the lighting designers. For example, the bridge turns on and off based on an astronomical clock within the Horizon system which automatically adjusts to the time of year. “If in June the bridge turns on at 5:30pm, the lighting system had to know not to run a top-of-the-hour show at 5:00 like it would in January.”
The system also needed to know not to run a train crossing sequence after one of the other sequences had been triggered. “On the same token,” says Evans, “if a train sequence started and then a top-of-hour or half-hour sequence was set to start, the top-of-hour or half-hour sequence would not start until the train sequence had finished. All of these logical decisions were accomplished using only the Horizon 2000 software.”
Evans points out that the Horizon system “allows for control of eight universes of DMX, but has a user interface simple enough for an electrical maintenance worker to do basic modifications without any entertainment lighting console experience. The ability to design a custom HTML (web page) user interface makes handling 4,096 channels of DMX much simpler than traditional control systems. The system is a Dell 750MHz PC with two video cards. This allows the HTML page to be viewed full-screen on one monitor, and the WYSIWYG real-time model to be viewed on the other.”
Using a PC and WYSIWYG, Evans was also able to do 99% of the programming at his home in Orlando. “The only modifications that needed to be made on-site were timing adjustments, and minor changes to the color palettes. The most time-consuming portion of the project was the full-scale 3D model drawing that was done in WYSIWYG. The 3D drawing is a simple representation of the bridge which gives users the ability to see in real time what the bridge is doing from the control room in Camden, which has a limited view of the bridge,” he notes.
The 72 High End EC-1s are positioned both above the roadway on special mounting arms to light the upper reaches of the towers, as well as below the bridge where they are attached to the structure of the roadway to light the lower portions of the towers as they stretch toward the water. The Atlantic City, NJ, office of Stone Mountain Productions served as the dealer of record for the High End fixtures, with project manager Rob Gosman providing pre-installation testing of the fixtures as well as on-site support and troubleshooting.
Special colors in the High End and Color Kinetics fixtures can be used for holidays, such as blue and white for Hanukkah, red for Valentine's Day, and green and red for Christmas, although the reds didn't look quite right against the blue of the bridge until special filters were added. The red was important since it plays a big role in the red, white, and blue patriotic looks for Memorial Day, the Fourth of July, Presidents Day, Veterans Day, and Flag Day. Different color combinations light the bridge in support of Philadelphia's sports teams when they play important games.
Over 2,000 cues were written for 25 special shows and sequences. “The sky is the limit,” says Edenbaum. “We have not finished designing shows yet. In fact, we are currently designing a new show to celebrate the 75th anniversary of the bridge this summer. We hope to remain involved with this project for a long time, designing shows for special events and holidays. Every year there is something new we can celebrate.”
Edenbaum also points out that “the client wanted full control of all lighting equipment. Since they do a lot of special events like fireworks and laser shows, they wanted to be able to turn it all on and off when they wanted to, without being dependent on a photocell and time clock arrangement.” This presented a problem for a handful of the floodlights located on poles around the base of the anchorages. “To get power to these fixtures, that the Delaware River Port Authority could control, meant trenching across city streets, private property, and, in one instance, the State Prison. An expensive and time-consuming undertaking in all cases,” he notes.
The solution was to use radio DMX transmitters and receivers from Interactive Technologies in Orlando. The fixtures were powered by the local utilities from existing poles. A radio signal is transmitted to a relay pack located on the floodlight pole that allows the light to be turned on and off when wanted. The radio signal emanates from the Camden anchorage and triggers the relay packs, some of which are across the river a mile away, without the need for direct line of sight, since the signal can pass through walls of buildings.
BRIDGING PAST AND FUTURE
The massive granite anchorages that sit on the shores are now lit with 250W metal-halide Sterner floodlights on poles. The light grazes the stone and adds texture to the outside of the structures. In contrast to this cool-colored light, the fenestration patterns at the top of the anchorages are lit with warmer high-pressure sodium Sterner floodlights. The large, carved State Seals on the outside of each tower are accented with narrow-beam metal-halide floodlights by Arc Sales. The existing fixtures were refurbished by Klemm Reflector, a Philadelphia firm dating from 1855. They restored and in some cases recast the fixtures, which were then relamped with 70W metal-halides. These are located at the anchorages at pedestrian level, at the base of the catenary cables, and at the top of the suspension towers.
One of the other aspects of the bridge lighting that was redesigned is the pedestrian walkway lights. “The original ones were too far apart to create a solid line of light,” says Grenald. The solution was to add additional fixtures, made to echo the old ones, and add long-life 70W metal-halide lamps, so that the lights now visually link the two shores of the river.
“We now have a multitude of sub-systems working together, creating a much stronger statement in the lighting,” says Edenbaum, who notes that area restaurants are happy about the new look of the bridge. “They have even asked for longer hours of performance of the lighting,” he adds.
“We've heard a lot of positive comments,” confirms Stashik. “The bridge looks fabulous at night when we can select what we want to see and make the rest disappear. That's the magic of lighting design.”
BENJAMIN FRANKLIN BRIDGE
Grenald Waldron Associates
Raymond Grenald, FAIA, FIES, FIALD, LC, partner-in-charge
Sandra M. Stashik, PE, FIES, IALD, LC, project manager
Daniel E. Edenbaum, IESNA, project designer
Brian F. Evans
Ed Gallagher, vice president and project manager
Joseph Jingoli & Son
Lonnie Kirk, office project manager
Frank Skinner, field project manager
|72||High End Systems100 EC-1s|
|384||Color Kinetics106 C-200 WaterColor LED fixtures|
|9||Arc Sales107 14"-diameter 150W metal-halide floodlights|
|86||Sterner108 250W metal-halide floodlights|
|24||Sterner 150W metal-halide floodlights|
|259||Antique Street Lamps109 pedestrian lights|
|207||custom street lights with 70W metal-halide lamps|
|4||Rosco/ET110 playback contollers with gold upgrades|
|2||Interactive Technologies111 radio DMX transmitters|
|3||Interactive Technologies radio DMX receivers|
|9||DMX Keeper112 16-channel relay control panels|
Circle Number on Reader Service Card