The Mid-Hudson Bridge spans the Hudson River from Poughkeepsie to Highland, N.Y., and officially opened in August 1930. The two-mile-long suspension bridge has had various upgrades made to it over the years, and in 2001, the New York State Bridge Authority (NYBA) issued its Request for Proposal (RFP) to install “necklace lighting” designed to accentuate the suspension cables at night. The goal, according to an article in the Poughkeepsie Journal, was to help promote tourism in the area and to spruce up the 71-year-old bridge, which is one of the region’s landmarks.
J.D. Parrella Electric Inc. (JDPE), headquartered in Newburgh, N.Y., about 60 miles north of New York City, put in its bid to be a part of history as the company that would install the first bridge illumination system made up of light-emitting diodes (LEDs). Because of the open nature of the bid and the absence of any prequalification requirements, Parrella had to compete against a wide range of electrical contractors. “Everybody from those with little or no experience, to those contractors with the same level of highly trained electricians on staff as us, was eligible to respond to the RFP,” said Steve Parrella, the company’s president.
About a month after the bids were submitted, JDPE was awarded the $300,855 contract based on its competitive price and its 35 years of experience in providing its customer base with a broad spectrum of electrical construction services in medium- and low-voltage installations in the commercial, residential, industrial and institutional markets.
JDPE had also worked previously on the Mid-Hudson Bridge in 1999, and was responsible for replacing all of the roadway lighting at that time. “That project consisted of replacing the entire roadway lighting system for the bridge with 48 20-foot poles, high-pressure sodium lights and a timeclock-based control system,” Parrella recalled.
The NYBA provided JDPE with the complete design of the necklace lighting system for the bridge. “Although we did not assist in the design of the system, our field electricians had to make on-site decisions and changes to the plans to fit the reality of installing lighting fixtures and fastening wires and conductors to such massive suspension bridge cables,” said Parrella.
With an average of five electricians on site, work commenced in April 2001 and was completed by Aug. 15. The necklace lighting was to be installed on the suspension cables of the bridge with the goal of providing decorative lighting that also enhanced traveler safety. JDPE installed the 142 LED light fixtures; 18,000 feet of power, control and fiber optic cabling; and the supports that would hold the fixtures to the bridge’s suspension cable.
“LEDs were chosen as the light source for the project because they consume approximately 20 percent as much energy as a conventional fixture, their service life is over 10 years and lumens of light for LEDs are only 5 percent of traditional sources,” explained Rich Schwarzbeck, JDPE’s senior project manager. In addition, LED light fixtures consume only 24W of power per fixture, use no moving parts and produce virtually no heat, noise or UV rays.
In addition to the LED lighting fixtures, JDPE was responsible for installing the PC-based control system that directs how the necklace lighting system is illuminated. With a total of 27,000 red, green and blue LEDs, custom light shows for the bridge are easily created on a personal computer and microprocessor technology enables the light show designers to create over 16.7 million colors and lighting effects. The iPlayer 2 playback device that controls the LED fixtures is located approximately one mile away from the bridge and data is sent to the lights through the fiber optic cables installed by JDPE.
A challenging operation
In keeping with the architectural trends of the times, there is a tower anchoring each end of the bridge. To run the wires for the lights and the fiber optic cabling for the communications system, holes had to be cut into the several-inch-thick steel of the towers. JDPE chose to subcontract that part of the job because even though the company has experience in that kind of heavy construction, it was believed that another company could perform the work more cost-effectively and make the final bid more competitive. “We engaged Piasecki Steel Construction Corp. from Castleton, N.Y., because that company has a great deal of experience in bridge work and could help keep the costs of the project down,” said Parrella.
Bridge work entails its own set of unique challenges, according to Schwarzbeck, mostly focusing on outdoor conditions and working at great heights. “Our electricians were working at angles as steep as 30 degrees and at heights as high as 200 feet above the bridge itself, with another 200 feet to the water,” he said. At those heights, there are no frames of reference for the electricians who were working on the large round tubes that hold the bridge’s suspension cables.
The first step in dealing with these challenges was choosing electricians who have had previous experience working in high and windy conditions and had conquered any of the fears they may have had. Then, each crewmember was outfitted with OSHA-approved double lanyard harnesses, which were inspected daily to ensure that they remained in perfect operating condition. “Weekly safety meetings were held to review procedures and to address any concerns by the electricians of the conditions,” said Schwarzbeck. In addition, if it were too windy or rainy to safely work on the suspension cables, focus on the site was switched to other tasks, such as running conduit through the bridge towers or prefabricating the cable supports that were used to hold the LED fixtures.
In addition, the material, equipment and light fixtures had to be raised and lowered to the points at which they were needed. JDPE’s foreman, Mike Joseph, devised a special pulley system consisting of bull wheels and rollers to pull the wire through to its high destinations. Special supports had to be used for mounting the pulley system because it had to be positioned directly onto the bridge’s suspension cable instead of on the road. “The system could not be anchored on the road surface because that would affect the integrity of the roadway and bridge,” Schwarzbeck explained.
This project is the first application of LED necklace lighting for a bridge anywhere in the country. Local civic leaders in Poughkeepsie believe the lighting will remind residents and visitors of what the area offers and the staff at J.D. Parrella Electric Inc. was pleased that their experience could be applied to this cutting-edge technology. EC
BREMER, a freelance writer based in Solomons, Md., contributes frequently to ELECTRICAL CONTRACTOR. She can be reached at 410.394.6966 or firstname.lastname@example.org.