The Bergen Point Wastewater Treatment Plant Outfall Replacement Project in Babylon (Long Island, NY) in which OHLA has participated in a joint venture, has received the Underground Construction Association’s 2022 Project of the Year Award in the $50 million to $500 million category. It is one of the largest construction projects in Suffolk County in decades and OHLA’s first project on Long Island.
OHLA USA has constructed a 10-foot diameter tunnel through a mixture of soft soil materials under the Great South Bay. The new 2.6-mile tunnel will address the concerns of potential failure of the current pipe and will have a longer lifespan. No carrier pipes will be installed within the tunnel; the lined tunnel itself will serve as the replacement outfall. The TBM entry and exit shafts were constructed using ground freezing techniques and extend to a depth of 80 to 100 feet below ground. The tunnel was excavated using a slurry TBM and concurrently lined with 48-inch-wide precast concrete segment rings. The scope of work also calls for replacement of the pipe and valves at the existing Final Effluent Pump Station, among other works.