Senior Design Expo 2023

Civil Engineering & Engineering Mechanics
Sunset Bay Terminal: Designing the Interborough Express Brooklyn Terminal Station
Amanda Klepper, Ameen DaCosta, Clare McGillis, Jenna Stewart, Sydney Umanah
The Interborough Express is a proposed passenger light-rail system that would connect
underserved areas of Brooklyn and Queens using the right-of-way of the lightly used Bay Ridge
Branch, currently used by freight trains. The daily weekday ridership is estimated to be 115,000
people, and it would connect with 17 different subway lines and the Long Island Railroad,
providing a crucial link in the area. Our project is to design the terminal station for this line by
the Brooklyn Army Terminal at the border of Sunset Park and Bay Ridge along the shore of New
York Harbor. Due to its location, it has been affectionately named the Sunset Bay Terminal. The
two-story station will be complete with shops and other passenger services, a connection to a
nearby ferry stop, an outdoor park, an elevated walkway to the street, and a train yard. Our
design also features an innovative green roof, optimized viewing of the scenic shoreline through
a glass window wall, and a central glass dome that illuminates a central atrium.
Our station design features a two story building with a footprint of 75,000 square feet, or
250 ft by 300 ft. The primary structural design utilizes steel columns and beams with 25’ spans
as well as reinforced concrete slabs. The lateral force resisting system features moment
connections addressing wind forces perpendicular to the wall faces. The primary loads addressed
in the design are dead loads from the structural members, interior, and green roof, live loads from
pedestrian traffic, and wind loads. We modeled the dome shaped skylight accounting for dead
loads from the glass and wind loads.
The station design also contains multiple green infrastructure elements: a green roof that
spans the entire area of the roof excluding the skylight, a water catchment system to collect
rainwater runoff to use for flushing the toilets, and multiple green areas on the property. The
green roof is composed of sedum, which is native to New York, drought-resistant, and easy to
maintain. Spanning the entire roof, our innovative rainwater harvesting system is a central
feature of the station design. Water will be filtered and directed through a pipe system and into a
storage tank. Once water collects the tank, it will then be reused throughout the building. It will
provide 318,750 cubic feet of water per year – saving $13,000 yearly.
The coastal placement of the station presents unique design and geotechnical challenges.
The groundwater level of the soil is around 1.5 ft below the surface. The site is directly underlain
by glacial till and fill from past construction projects. This soil is weak and unfit to support the
load of the terminal. Beneath this glacial till, there is gravelly sandy loam, which will be better
suited to support loadings. Thirty-six cast-in-place, point-bearing concrete piles will be used to
support the structure. Cross sections of the piles will be 2 ft by 3 ft and driven 20 feet below the
surface. This will provide more than enough bearing capacity for the building’s live and dead
loads.
This terminal station will be owned and operated by the Metropolitan Transportation
Authority (MTA). The work will be contracted out using a Design-Build project delivery
method, designating a single team for the design and construction of the entire project. This
ensures smoother coordination of materials and efficient scheduling. The design, planning and
construction for this terminal station is estimated to take 3 years.
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