Westchester County owns and operates five tide gate regulators in the combined sewer area in the City of Yonkers. The overflow from the regulators discharges to the Hudson River that experiences significant tidal fluctuations. Tide gates in the regulators open during significant wet weather events to allow excess rainwater to discharge to the river through overflow pipes. During high tides, the tide gates close to stop river water from flowing back into the County’s combined collection system. The tide gates in the regulators needed replacement and/or repairs because the gates had developed leaks, allowing river water to enter the combined sewer system during high tides. The USEPA issued an Order on Consent to Westchester County to address the deficiencies and complete construction in a compressed timeframe.
EDR provided design and construction administration services for the $2,000,000 project to replace tide gates and improve access to five regulator structures in North Yonkers, Central Yonkers, and South Yonkers Sanitary Sewer Districts. EDR prepared a preliminary design addressing replacement of the tide gates and provided recommended improvements to access to the regulator structures that would allow for improved future maintenance of the gates. The existing cast iron gates consisted of three 48” diameter gates, two 3’x4’ gates and one 5’x6’9” gate. Access to the gates was complicated because the regulator structure locations are in busy street intersections and on MTA property requiring coordination with City of Yonkers and the MTA. Additional improvements that were identified included installation of new concrete slabs and access hatches that would allow access to both the upstream and downstream sides of the gates for observation and future maintenance. Due to the compressed timeframe dictated by the USEPA order, the County made an emergency declaration and awarded the project to their on-call emergency contractor. EDR worked closely with the contractor to finalize the design, order the required replacement gates, and complete gate installation and regulator improvement prior to the USEPA deadline.