Staggered Secondary Screens - A Small-Space Solution for New York City’s Newtown Creek Wastewater Treatment Plant

The Newtown Creek Wastewater Treatment Plant (WWTP) has been recently upgraded to achieve secondary treatment levels (i.e. 85% Removal of BOD and TSS). To satisfy plant site space constraints, the upgrade provided for installation of fine bar screens for primary treatment in lieu of primary settling tanks. This paper discusses the basis of design for the bar screens, the design of the screenings structure, and testing the flow pattern through the screenings structure via visual flow dynamics modeling. The field observations after the screens were placed into operation and the subsequent revisions to the screens operational strategy, as well as to the screenings equipment design, are also discussed. The secondary screens continue to perform reliably and efficiently, thereby providing an unconventional long-term solution for primary treatment at New York City’s largest WWTP.