Village of Northport Shoreline Sewer and Pump Station

Northport, NY

Incorporated Village of Northport

Contract Value:
$5.8 Million

Project Dates:
January 2017 - January 2018

  • Steel sheeting over 50 feet deep
  • Directional drilling of 12” HDPE pipes underneath the waterbed
  • Sanitary and sewer work
  • Underwater connection of homes to the new main


The project involved the replacement of an antiquated sewer and Pump Station. The infrastructure, over 70 years old, was located along the intertidal zone in Northport Harbor on the North Shore of Long Island, New York. The pipe entered the shore at Fifth Avenue and travelled south towards the Beach Avenue Pump Station for approximately 2,000 LF.


The geographic location of the infrastructure meant the work area was subject to floods with 10-foot tide changes. In addition, the work outlined needed to be performed directly alongside an active sewer pipe from the 1940’s that was deteriorated well beyond its useful lifespan and presented a constant risk: any contact with the pipe had the potential to result in an emergency sewage spill. The sewer and pump station operations were kept running throughout the duration of the project, until the new pipe and pump station were tested and accepted.


To manage the risk of flood, Posillico planned diligently and worked around the changing tide schedule throughout the project. Watertight steel sheeting was vibrated in, to depths of over 50 feet, to install the deep pump station. And to limit any potential environmental disturbance to the benthic underwater community, Posillico selected to perform 1,600 LF of directional drilling of 12″ HDPE pipe underneath the harbor floor as opposed to using the open trench method. The Posillico team then bypassed the entire Village sewer system to divert the flow to the new sewer and pump station, using divers to connect existing homes to the new main under water.