Hudson River Dredging Continues for Tappan Zee Bridge Project

Tappan Zee Constructors, LLC are continuing dredging operations this week near the Westchester shoreline as part of the preparation for removing the existing bridge and completing the New NY Bridge project’s eastern landing, according to the New York Thruway Authority.

Dredging is allowed during a three-month period from August 1 to October 31 in specified locations and will be conducted 24/7 to complete the required dredging during the short window, officials said. The window was established to avoid impacting migration and spawning patterns of local sturgeon and other fish species.

The current dredging operation is stage two, and is much smaller than the first stage. It is designed to create an access area for the I Lift NY super crane to remove sections of the existing bridge and build the southbound landing of the new bridge. The dredging will deepen the water level in the work zone by removing an estimated 187,960 cubic yards of sediment from the river bottom.

Tappan Zee Constructors, LLC are using specially-designed environmental clamshell buckets to perform the work. The buckets release less sediment into the river than conventional equipment, which further protects local aquatic resources.

Additionally, TZC has “provided environmental training to field personnel on procedures to protect sturgeon, including the use of specialized equipment to safely retrieve, keep alive and return to the river any fish that are inadvertently caught during the dredging operation.” Observers approved by National Marine Fisheries Services will oversee dredging activities to monitor for any possible sturgeon interaction and document any observed fish that may be collected.

The dredged river-bottom mud, which has been tested by TZC, will be processed and properly disposed at offsite locations.

Once the second stage of dredging is complete, approximately two feet of gravel will be placed in the dredged channel to limit the stirring up of river sediment when working vessels traverse the area.

Photo credit: New York State Thruway Authority