GNWPCD Wastewater Treatment Plant Expansion and Improvements

The upgrade and expansion of the Great Neck Water Pollution Control District’s (GNWPCD’s) existing 3.8 MGD wastewater treatment plant was designed to achieve the required effluent nitrogen removal as required by the State Pollutant Discharge Elimination Systems permit limits on effluent nitrogen imposed by New York State Department of Environmental Conservation/Long Island Sound Study. The project also expanded the plant’s capacity to 5.3 MGD to meet the new system demands after the Village of Great Neck consolidated into the GWNPCD and eliminated its 1.5 MGD wastewater treatment plant. The scope of the assignment included:

  • Construction of a new oxidation ditch
  • Construction of three new final settling tanks, including a new final settling tank influent distribution chamber
  • Upgrade of the influent screening system
  • Upgrade and expansion of the grit removal system to a vortex grit system, including the installation of a new grit removal tank and upgrade of the existing grit handling equipment
  • Upgrade of the existing primary sludge pumping system
  • Chemical storage and feed system to provide for chemically enhanced primary treatment
  • Construction of an RAS/WAS pumping station
  • Construction of a UVE disinfection system
  • Abandonment and demolition of the existing trickling filters, final settling tanks, chlorine contact tanks, hypochlorite storage and feed system, and effluent sand filters