North Yonkers Sewer District

Yonkers, New York

The Westchester County Department of Environmental Facilities hired H2M to help rehabilitate the Alexander Street and Irvington Pumping Stations in the North Yonkers Sewer District.

The Alexander Street Pumping Station was originally constructed in the 1930s and was last rehabilitated in 1992. The Irvington Pump Station was constructed in 1976 and last saw rehabilitation
in 2002. Both were due for an evaluation of existing conditions and rehabilitation. H2M assessed of the condition of each pumping station, including the station’s size, pumping capacity, electrical equipment, HVAC equipment, roofs, stairs, and odor control systems and made recommendations for improvements to meet current design standards.

The Alexander Street Pumping Station average daily flow is 1.055 MGD with the peak hourly design flow of 3.09 MGD. The pump station upgrade included a new prefabricated building to house headworks equipment with a separate room for the electrical equipment necessary to support the Alexander Street Pump Station’s electrical independence from the North Yonkers Pump Station. The rehabilitation also involves upgrades to wet well and dry well equipment, including new dry pit submersible pumps, piping and associated valves; sump pump; automatic bar screen; odor control system; and flow/level sensors. H2M assessed the stairs, walkways, gratings, and rehabilitation of the wet well, dry well, and tunnel roofs and made repairs as necessary. H2M’s design also provided adequate lighting and mechanical ventilation in the wet well and dry well.

The Irvington Pump Station average daily flow is 1.37 MGD with the peak hourly design flow of 3.86 MGD. The pump station upgrades include adequate lighting and mechanical ventilation throughout the wet well and dry well. H2M’ design included replacement of the stairs, exterior doors, hatches, roof, gutters, and leaders. These new leaders were designed to direct rainwater away from the building and not discharge into the wet well or sanitary sewer. The design also includes repointing/replacement of brick on the control building as necessary; paint exterior metal; and add new asphalt and concrete sidewalks. The existing underground fuel tank for the generator will be abandoned in place. A new 975-gallon aboveground fuel tank will be installed outside adjacent to the dry well, and a new Con Ed 480V electric service will be installed for the pump station.