During the week of April 5 the Gowanus Remediation Team continued working along the canal. Crews continued dredging and raking the canal bed and mobilized additional equipment for pile driving operations.
This week dredging continued between the Carroll Street Bridge and the 3rd Street Bridge. The dredged material is loaded from smaller “mini” hopper barges that can navigate the narrow canal to the transloading area at Huntington Street. The dredged material is then dewatered and transloaded to larger barges and shipped across New York Harbor to the dredged material processing facility in New Jersey.
After dredging the target area, our crews raked the canal bed using an excavator equipped with a rake attachment. Raking the canal bed is conducted as preparation for in-situ stabilization (ISS). ISS is a remediation process by which contaminants are rendered immobile through reactions with stabilizing compounds mixed directly into the soil or sediment.
Pile driving operations continued this week. The GRT repositioned the work barge and completed the transfer of an additional crane that was floated to site. The work barge is utilized for staging equipment and materials that are necessary to complete ongoing pile driving operations.
Crews completed pin pile installation at Turning Basin 1 (TB-1). Pin pile installation involves driving steel piles (similar to steel beams) into the canal bed at multiple locations in order to support steel templates utilized as a guide for pipe pile installation. Pipe piles will be installed at TB-1 to create a temporary bulkhead wall to support fill materials on the upland side of the canal while dredging occurs. Ultimately, the Carroll Street Bridge and the Union Street Bridge will have pipe pile walls installed as bulkheads to support the bridge abutments during future phases of dredging.
Next week crews will continue raking between the Carroll Street Bridge and the 3rd Street Bridge, and preparing equipment and materials for pipe pile installation at Turning Basin 1.
The Carroll Street Bridge will remain in the open position while the New York City Department of Transportation (NYCDOT) performs maintenance on the bridge. Carroll Street will be closed to vehicular and pedestrian traffic until further notice.
Photos of construction activities are provided below.