Challenge
Three privately owned marinas; Pike Marine, Perkins Marine and Essex Marina are located on the Essex River in Essex Massachusetts. The Essex River was last dredged in 1993. Shoaling of the subtidal and tidal areas of the river has occurred. The shoaling has also rendered a sizeable portion of the marina slips unusable due to lack of water at low tides. In 2021, the US Army Corps of Engineers (USACE) began planning activities prior to dredging the Essex River Federal Navigation Project (FNP), however this did not include areas within the private marinas adjacent to the FNP.
Solution
To save on the design, sampling and permitting costs, The marinas contracted with GZA collectively, but separately, to perform initial services. In addition, the marinas’ goal was to “piggybacking” onto the proposed the dredging that was to be performed by the USACE. GZA and the three marinas were on a tight timeline to have dredging permits in hand prior to the USACE Essex River FNP project. GZA began with bathymetric survey and limited topographic survey of the three marinas to develop the dredging design for each marina. The design included analysis of historically authorized dredging areas and depths to differentiate between “maintenance” and “improvement” dredging. Once volumes and areas were estimated, GZA coordinated with the USACE reviewers to develop a Sampling & Analysis Plan (SAP) to support open ocean disposal and, therefore piggyback on the USACE FNP project. A multi-phased sediment and elutriate sampling effort was accomplished with samples being shipped cross country to approved laboratories on the west coast and east coast. Once the sampling and analysis was completed, GZA completed permitting efforts through the Massachusetts Environmental Policy Act (MEPA) Office, the local Essex Conservation Commission, the Massachusetts Department of Environmental Protection Chapter 91 and 401 Water Quality Certification Programs, and a USACE Individual Permit.
Benefit
GZA worked tirelessly to have permits secured to allow the FNP contractor to dredge the marinas with over 1.5 months remaining within the dredging window. Due to issues with the contractor, the marinas were not dredged during the 2025 season; however, the marinas’ have up to five years to have the dredging work performed.
