As a subconsultant, SI Engineering, P.C. (SIE) provided engineering design and construction support services for improvements to the CSO disinfection facilities located in the Tallman Island drainage watershed area of Flushing Creek at Outfalls TI-010 and TI-011 in Flushing. The project included facility planning and design of proposed disinfection and dechlorination facilities to protect and enhance the water quality discharging to Flushing Creek from May through October. To meet water quality goals, new chemical dosing facilities will be constructed along the CSO discharge sewers to the Creek. Separate new buildings will house tanks providing chemical disinfection of the discharge water, while further downstream, new buildings will dispense dechlorination chemicals to remove disinfection residuals in the water prior to discharge to Flushing Creek.
SIE supported completion of the Basis of Design Report (BODR) for the project. The initial tasks included traffic analysis and evaluation of alternative locations for the disinfection and dichlorination facilities. Work included conducting visual inspections, providing photographic documentation of existing conditions, and providing evaluations of traffic and site conditions summarized as an addendum to the BODR.
Further work included a detailed traffic analysis during City Environmental Quality Review (CEQR) and in preparation of the Environmental Assessment Statement. Detailed assessments and mitigation of the alternatives were conducted in accordance with the DEP’s Bureau of Environmental Planning and Analysis (BEPA). The work will further include collection of traffic data, providing simulations, determining level of service, describing and illustrating existing and future seasonal traffic conditions in the area due to the added operations, and preparing 30%, 60%, 90%, and 100% design and contract documents for site improvements at each of the facilities followed by construction phase services.
