Its the Bergen Outfall Pipe Upgrade!
OHL USA, Inc., an OHL North America company, announces it has been awarded a $187 million joint venture contract (40% OHL USA, Inc., 40% Posillico Civil, Inc., 20% SELI Overseas USA, Inc.) by Suffolk County Department of Public Works to replace existing outfall pipe at the Bergen Point Waste Water Treatment Plant (WWTP) in Babylon, NY. This is the largest construction project in Suffolk County in several decades and OHL’s first project on Long Island, expanding OHL’s regional presence in the New York area. Construction started on February 8th, 2018 and will be completed by summer 2021.
The project includes the construction of a 14,200-foot, 120-inch
inner diameter tunnel through a mixture of soft soil materials under the
Great South Bay with the use of a tunnel boring machine (TBM). The
tunnel will be constructed to replace the existing Prestressed Concrete
Cylinder Pipe (PCCP) outfall pipe, which carries
millions of gallons of treated wastewater, connecting the Bergen Point
Wastewater Treatment Plant (WWTP) to the Barrier Island under the Great
South Bay. The new tunnel will address the concerns of potential failure
of the current pipe and has a longer lifespan.
The tunnel will be excavated and concurrently lined using precast
concrete segment rings. The JV has selected a slurry TBM as the most
effective and efficient means of tunnel excavation and elected to use
48-inch wide precast segment liners. The shaft construction will be
divided into major work phases including site preparation, excavation of
the launch shaft and installation of the new slurry TBM. Once the TBM
is installed, tunnel excavation will proceed in four foot “pushes,”
followed by the installation of the permanent tunnel lining.
Additionally, the team will also complete ancillary work within the
tunnel including the installation of new piping and valving, associated
plumbing, HVAC, and electrical work.