Urbahn Architects, Gramercy Group complete renovation at MTA's Eastern Parkway – Brooklyn Museum subway station
An extensive renovation of the Metropolitan Transportation Authority’s (MTA) Eastern Parkway-Brooklyn Museum subway station on the IRT Eastern Parkway Line has been completed by Urbahn Architects and contractor Gramercy Group.
This station, serving subway trains on routes 2 and 3, was identified in the MTA 2015-2019 Capital Plan as one of a group of key stations throughout the New York City subway system that would be made fully accessible in order to better serve riders.
The enhancements, which included the installation of three hydraulic elevators and the replacement of one street level stair, achieve full ADA compliance and have improved customer ingress and egress.
“This is a popular station for those heading to local institutions such as the Brooklyn Museum, whose advocacy and support helped get this project done,” said Sarah Meyer, New York City Transit Chief Customer Officer. “By adding elevators and other ADA features we are not only helping improve accessibility for local residents, but making our stations inclusive for all those visiting, as well.”
Natale Barranco, Urbahn Architect’s principal-in-charge, added, “This $25.8 million public transportation project that serves visitors to the Brooklyn Museum and Brooklyn Botanic Garden was both technically challenging and satisfying. The station had to remain fully operational during construction, with the goal of full accessibility upon completion. Urbahn worked closely with MTA C&D and with the contractor, Gramercy, to ensure that the work was adequately phased and remained on schedule. The project’s duration was 28 months.”
In addition to Barranco, Urbahn’s team included Project Manager Nandini Sengupta; Project Architect Ijeoma D. Iheanacho; and Construction Administrator Siddharth Tailor. Joseph Castaldo, vice president of operations, and Scott Krokoff, construction project manager, led the Gramercy team.
Additional design and construction team members included structural and civil engineer TY Lin International; mechanical, electrical, and telecommunication engineer GG Engineering; vertical transportation consultant AB Consulting; surveyor Matrix New World Engineering; cost estimator ELLANA, Inc.; and maintenance and protection of traffic planner SIMCO Engineering.
Vertical accessibility and mezzanine renovations
“Urbahn’s initial task was to evaluate the potential for improving vertical accessibility from the street to the east mezzanine and then to the platforms,” said Sengupta. “Installation of an elevator from street level to the mezzanine was a requirement, as was the installation of two additional elevators from the east mezzanine to the individual northbound and southbound platforms.”
Upon evaluating the site, Urbahn determined that the museum plaza was the ideal location for the street elevator because there was open space surrounding the existing stair and there was direct access to both the museum and the botanic garden. The existing stairs in that location had been installed approximately 20 years ago and were ADA compliant. However, the existing stair in the traffic median did not meet ADA requirements and required complete replacement.
To accommodate the elevators, the east mezzanine had to be modified in three separate areas. At the plaza entrance, the entire mezzanine width was extended by approximately 24 feet to incorporate both the street level elevator shaft and an elevator equipment room. The elevator leading from the mezzanine to the southbound platform was located within the existing mezzanine footprint, but structural modifications were required to form a shaft and to also create a pedestrian access area outside the station envelope at the platform level. Finally, the elevator and associated mezzanine and platform access areas for the northbound platform fell entirely outside of the existing footprint, requiring additions below the service lane at the north side of the station.
The employee and utility areas were redesigned to accommodate the new elevator floorplan and ADA requirements, and the concession area was converted to a dry storage room.
The project also included a new closed-circuit television (CCTV) security system, fire alarm system, refurbishment of the station agent booth for ADA compliance and a local area network to support the rollout of MTA’s new fare payment system. The equipment room for the CCTV and other communications systems is located at the west employee mezzanine.
Design components
The elevators are hydraulic units, manufactured by Mid-American Elevator Co. A 15-foot-high glass and steel tower with a cantilevered canopy, enhanced by LED lighting and station signage, encloses the street level entrance. This glass box, highly visible both during the day and at night, adds visual interest to the project and enables the addition to blend seamlessly with the surrounding plaza.
The existing street level plaza stair adjacent to the new elevator was not modified. The plaza slopes down from the street toward the museum entrance at a lower elevation. To achieve ADA compliance, the crews replaced existing steps at the plaza with a ramp, which connected the grade level at the elevator entrance to that of the lower walkway.
At the mezzanine level in this location, the elevator machine room (EMR) wraps around the elevator shaft. The EMR contains three oil coolers for the hydraulic machines, which generate a substantial heat load that requires exhaust. The Urbahn team designed a 25-foot plenum exhaust that extends along the length of the ramp and forms a low wall containing exhaust grilles on one side and supporting the ramp handrail on the other. The EMR exhaust plenum’s low wall was clad in granite supplied by Miller Druck Specialty Contracting and the team sourced granite to match the existing granite on the top of the stair wall at the plaza.
The street level stair at the pedestrian mall has been replaced and its width increased from six feet to seven feet, six inches to meet additional passenger capacity as determined by MTA C&D. Excavation work for this new stair, as well as for the installation of the new northbound platform elevator, required the excavation of over 60 feet of the pedestrian mall and north service road to the depth of 36 feet. The mall surface consists of granite curbs and octagonal asphalt pavers and is interspersed with trees. Gramercy sourced granite material and the pavers to match existing materials and integrate the new surfaces within the construction zone with the existing landscape fabric. New York City Department of Parks & Recreation will plant replacement trees.
“The project included a unique art restoration component,” shared Sengupta. “During a 2003 MTA renovation of the station, a total of 60 terra cotta and stone pieces from the museum’s collection of façade decorations salvaged from New York City buildings were installed on the station walls, surrounded by glass mosaic borders. Five of these pieces were located adjacent to the plaza stairs and had to be removed to permit construction of the mezzanine extension. Urbahn coordinated with MTA C&D and developed a specification for the removal, protection, and reinstallation of the artwork in a new location. Gramercy carefully removed the affected pieces and stored them in custom-made plywood crates during construction.” Additional areas of the mezzanine walls were also barricaded to protect pieces that remained in place. A custom tile shop matched and replicated the mosaic borders to enable the reinstalled pieces to blend with the original installations.
The completed project has resulted in a fully accessible station. The new elevators and stairs provide an unobstructed path from the street level to the train platforms. The 24-hour agent booth has been modified to include an ADA deal tray. Additional accessible features include new tactile Braille signs, Autonomous Farecard Access System (AFAS) gates, and platform edge tactile warning strips at ADA boarding areas.
Utility and infrastructure work
Lighting fixtures throughout the renovated mezzanine areas and the new platform level elevator access areas were replaced with new ceiling mounted linear tube LED fixtures by Apogee Translite. New LED lighting strips by Minestone illuminate the undersides of the handrails at the new pedestrian mall stair.
In the elevator equipment room, air temperature is maintained by 4500-cfm exhaust and recirculation fans that vent to the new exhaust plenum. Additional exhaust fans were installed throughout the east mezzanine employee service areas. At the west mezzanine communications room, a new split-type cooling unit was installed to address increased heat load created by the expanded CCTV, fire alarm, and communications systems.
“Three individual areas of street level excavation were required for the elevator installations, and some existing utilities were affected,” explained Joseph Castaldo, PE, Gramnercy’s Vice President of Operations. “Most significantly, a 21-inch water main crossed over the new southbound platform elevator excavation. Construction crews installed a beam across the excavation pit to support the line, and heat traced and insulated the pipe so that it would not freeze while it was exposed during the winter months,” he added. A combined sewer line in the same area was rerouted around the pit. Other required utility relocations included a lamppost, two traffic signal posts and conduit, and a fire hydrant.
Construction and schedule challenges
The project presented several phasing and logistical challenges. According to Castaldo, “The team had to be creative with logistics and materials staging to perform the work within tight space and schedule confines.” Three separate excavation areas were required. The pit for the plaza elevator was located adjacent to the existing subway entrance and impacted access to a museum parking lot entrance. The two pits for the platform elevators were both located within or adjacent to Eastern Parkway traffic lanes and extended to a depth of over 36 feet below grade. All three locations had very limited space in which to work, and all operations had to be scheduled so that traffic impacts were minimized. During excavation, the crews encountered a number of car-sized boulders that had to be split and removed in sections, slowing down the process.
Once the bottom of the excavation pits was reached, the team discovered that the bearing capacity of the soil was not adequate to support the mezzanine extension footings. In order to address this issue, the team installed twelve piles, each between fifty and sixty feet deep and extending to a bottom depth of about eighty feet below grade. Steel pipe casings were installed on the upper fifteen feet of the piles, the remaining depth as well as the casing interiors were grouted, and pile caps were installed on top. Because the limited access within the excavation pits could not accommodate a standard drill rig, an excavator with a drill attachment was instead used for the installation of the piles.
Several existing mezzanine and platform level columns were located immediately adjacent to the excavation areas and had to be underpinned. This work proved to be time consuming and exacting. Laborers inside the station built underpinning pits with timber lagging and sheeting, and manually dug under each column as the pits had to be completed before the crews could excavate the areas adjacent to the columns. As each section was exposed, the pits were filled with concrete to underpin the columns.
In Spring 2020, as the street elevator structure was under construction, the COVID outbreak forced a temporary closure of the factory manufacturing the metal roofing for the expanded mezzanine level resulting in a five-week schedule delay.
Phasing was a critical consideration as the station had to maintain operation and car traffic flow on Eastern Parkway could not be disrupted. Work was carefully planned to ensure that passengers had continuous access to the gate and platform areas, employees had access to the service areas, and vehicular traffic on the street level was maintained. The work was divided into three main phases: northbound elevator, machine room and street elevator, and southbound elevator.
The most critical phase was the southbound elevator excavation, as it required significant work in the middle of Eastern Parkway that impacted traffic and pedestrian flow. Gramercy developed Maintenance and Protection of Traffic (MPT) plan, meeting the NYC Department of Transportation’s standards. The MPT plan permitted the closure of one of the traffic lanes for six weeks. The lane reopened to traffic once the decking system was installed. Once the structural work was completed and the roof deck over the new mezzanine area was poured, the temporary road deck was removed and the area backfilled and repaved.
Gramercy coordinated extensively with both the Brooklyn Museum and the Brooklyn Botanic Garden to ensure that public access to major planned events was maintained throughout the project duration. The Eastern Parkway entrance to the museum parking lot had to be closed during much of construction, and Gramercy provided signage to redirect traffic. They worked with the Botanic Garden to temporarily reopen the parking lot entrance for the popular Cherry Blossom Festival weekend. In addition, the crews relocated barriers and constructed temporary stages for the 2019 West Indian Day Parade and for the Brooklyn Half Marathon.
