New York City Department of Environmental Protection

To improve sludge boat mooring at the Owls Head Wastewater Treatment Plant (WWTP), we performed a phased demolition and reconstruction of the low level relieving platform that carefully kept shutdowns to a minimum and avoided impact to the plant’s daily operations. Work spanned piles, walers, deck, and sea walls along with the installation of new sludge piping and water mains.

This project included the installation of 24” digested sludge piping from the sludge storage tanks to the west dock sludge loading station including 12” sludge nozzle assemblies. All piping material was glass interior lined ductile Iron Class 54 with retrained joints.

New sludge piping was installed on concrete cradles. Installation included 24” MJ x MJ flex-tite double ball expansion joints for thermal expansion and tie-in to the existing 24” underground sludge piping. The complete system was tested at 100 psi for two hours.

We also installed the new 8” DIP watermain and fire hydrants along the new piers. The new watermain was supported from new piles. Tie-ins from the new watermain to the existing water main on both ends were scheduled and completed.