April 2007 – September 2007
$ 4.08 MM
The size of the restoration was 35 acres and included 65,000 CY of excavation that included 55,000 CY of marsh plain excavation, 10,000 CY of channel excavation and 16,000 CY of imported sand to construct high marsh.
The Secaucus High School project was part of a larger regional effort to enhance habitat and increase public access, creating a series of greenways along the highly urban shoreline of the Hackensack River in the Hackensack Meadowlands District. The Secaucus High School property adjacent to the Hackensack made it an excellent location for restoration and access for the community. The 35 acre degraded wetland was dominated by invasive Phragmites. The Louis Berger Group designed and permitted the restoration that required removal of one foot of Phragmites dominated root mat. 65,000 CY of material was excavated and hauled to be reused for cover at a landfill site controlled by the Hackensack Meadowlands Commission. Excavation was accomplished by the use of track excavators positioned on timber crane mats to support the weight of the machines on the soft substrate. A 2700 linear foot berm was constructed parallel to the Hackensack River to prevent river inundation of the work areas during storm events. Pipes with tide gates were installed in this berm to allow the site to dewater during the excavation operation. Since the site was 35 acres, 8’ X 15’ wooden mats were used to construct haul roads to access the excavated materials. These mat haul roads spread the load allowing equipment access over the soft marsh plain unsuitable for conventional equipment. These roads were sequentially moved and repositioned to access the new excavation areas. Low ground pressure tracked haulers were employed to move the excavated soil and root mat to the upland staging area. This material was dewatered and then loaded on conventional dump trucks to remove the material and transport it to the designated landfill. Following the restoration a 2,700 LF raised boardwalk was constructed to allow pedestrian access from Mill Creek Park to Secaucus High School along the river.
New canals were excavated to allow the site to tidal flush in order to establish a new low marsh Sand fill was imported to raise the elevation on a portion of the site to construct an area of high marsh to add species and habitat diversity. Transition areas upland to the marsh were established as native warm season grass meadows and shrub-scrub habitat. A 2700 LF pedestrian boardwalk was constructed parallel the river to allow access from Secaucus High School and Mill Creek Park.