22-532 - Air Vacuum Valves Installation North Yonkers Pump Station, Yonkers, N.Y.

The work under this contract consists of providing all necessary labor, material and equipment required to replace the existing surge chambers and manual air release valves, which have exceeded their useful life, with combination air/vacuum release valves for automatic venting of the 54-inch diameter RCPP force main from the North Yonkers Pump Station to the Yonkers Joint WRRF located in Yonkers, New York. The 8,000 LF force main was constructed in 1960 and included the installation of ten (10) surge chamber/air release valves at the high points and the 90-foot deep inverted siphon, crossing beneath the Domino Sugar Factory, along the force main. These chambers and valves helped to relieve excessive pressures that accumulated in the 54" force main. The manual air release valves have deteriorated and the force main has experienced excessive surge pressures in the proximity of the inverted siphon which has resulted in damage to the existing air release valve and piping at this surge chamber, which is referred to as the North Shaft.  It has been determined that a minimum of 6 new air/vacuum release valves and manholes will be installed to adequately protect the 54" force main.  (Bid range: $1,800,000.00 to $2,200,000.00).