- Company: JT Cleary, Inc.
- Industry: Transportation
- Location: Chestnut Ridge, New York
- Expected Completion Date: June 12, 2015
- Project Website
The Gerritsen Inlet Bridge is one of seven bridges on the Shore (“Belt”) Parkway to be replaced by the New York City Department of Transportation (NYCDOT). The work on the Gerritsen Inlet Bridge is divided into three phases, each of which is approximately equal in size and scope. Phase I of the project was completed in 2015, and Phase II is currently underway.
JT Cleary is teamed with CCA Civil, the general contractor, and is responsible for installing the marine foundations for the new bridge. JT Cleary’s scope includes cofferdam design and construction; excavation of the cofferdams; supply and installation of concrete pilings and concrete tremie foundation; and installation of recycled plastic timber for fender and dolphin systems.
What impact does this project have on America?
Many New York City bridges are well beyond their original design life. In addition, they were not designed for the exponential increase in vehicular traffic that they have been subjected to over the last 50 years. The practice of lane closures to maintain these old bridges is a losing battle, and a very expensive one. The loss of productivity due to traffic jams caused by lane closures is significant and negatively impacts the local economy. Conversely, providing safe and efficient transportation is key to boosting employment.
These new bridges will have wider lanes, safety shoulders, median barriers, and improved vertical and horizontal alignments. NYCDOT anticipates that these improvements will reduce the current accident rate substantially on this section of the Belt Parkway. The significant improvement to public safety is the most important reason to build a new bridge.
What interesting obstacles or unusual circumstances did you overcome to complete the project?
JT Cleary used its technical expertise to overcome challenges during Phase I. For example, the company is very experienced in performing highly skilled work during frigid New York winters and successfully completed two, mass concrete placements of 1,100 cubic yards each during the winter months to keep the project on schedule.
The team resolved an unusual circumstance in which the location of the old bridge foundation was not always as indicated on the contract drawings. JT Cleary overcame this by re-designing the cofferdam, in coordination with the general contractor, to fit around the existing bridge foundation. The foundation piles also did not fetch up to the design capacity for the specified tip elevation. To surmount this, the owner added more piles, and JT Cleary once again re-designed the cofferdam, and the project proceeded smoothly and without issue.
What dangers and risks did you encounter, and describe any extraordinary methods used to keep workers safe?
JT Cleary’s approach is to engineer the danger out of every project, so that extraordinary measures are not required. Good planning creates a safe environment at the site, so workers never feel compelled to take unnecessary risks.
As part of this project, cofferdams were excavated in the waterway, followed by installation of pilings for the bridge foundations. The company deployed its commercial divers inside each cofferdam to level the base, thereby ensuring a good seal after dewatering. Although some may consider commercial dive operations inherently dangerous, for JT Cleary it was a routine and safe operation. The company adheres to the most conservative interpretation of safety standards for commercial diving, and the work at Gerritsen Inlet Bridge was completed successfully without incident.
How did you leverage new technologies to work faster and reduce waste?
To dredge out the cofferdam, the JT Cleary used a hydraulically actuated clamshell bucket, instead of the traditional wire handled bucket. This, in turn, allowed use of a much larger bucket, which dramatically improved productivity and reduced time to completion.