The USACE Philadelphia District maintains 500 miles of navigation channels across five states, including the 117-mile long New Jersey Intracoastal Waterway and multiple coastal inlets in New Jersey and Delaware. These waterways are periodically dredged to provide for safe maritime navigation. When the dredged material is clean, USACE looks for opportunities to use the material beneficially. Examples include restoring degraded marsh and creating islands, which can provide critical habitat for wildlife and enhance coastal resiliency. 

These practices have occurred historically, but the concepts have gained increasing attention and focus in the years since Hurricane Sandy in 2012. The USACE Philadelphia District is engaged in beneficially using dredged material in several ways:

• The District has championed Regional Sediment Management projects for more than twenty years since the program's inception. 
• In June 2016, the Philadelphia District became an Engineering with Nature Proving Ground. This program seeks to align natural and engineering processes to efficiently and sustainably deliver economic, environmental, and social benefits through collaborative processes. 
• In April 2019, the Philadelphia District partnered with the New Jersey Division of Fish & Wildlife and The Wetlands Institute to launch the Seven Mile Island Innovation Lab (detailed below).  

In Spring 2019, the U.S. Army Corps of Engineers Philadelphia District partnered with the State of New Jersey, The Wetlands Institute, and the USACE Engineer Research and Development Center to launch the Seven Mile Island Innovation Laboratory (SMIIL).

Seven Mile Island, New Jersey was chosen to host an Innovation Lab due to the presence of existing and historic dredged material placement sites, confined disposal facilities, federal and state channels including the New Jersey Intracoastal Waterway, extensive tidal marshes, a mixture of sandy and muddy sediments and, a rich historic dataset to build upon. The initiative is designed to advance and improve dredging and marsh restoration techniques in coastal New Jersey through innovative research, collaboration, knowledge sharing and practical application. SMIIL is based on an international concept pioneered by the Dutch who use a “Living Lab for Mud” to test and demonstrate environmental and societal benefits.

Maintaining safe navigation channels while retaining dredged sediment in the system to benefit natural ecosystems and coastal communities. (NOTE: In December 2019, the name was changed from the Seven Mile Island Living Lab to the Seven Mile Island Innovation Lab to better reflect goals and objectives). 

• SMIIL Overview & Purpose Factsheet
• SMIIL Field Data Collection Factsheet
• SMIIL Scotch Bonnet Factsheet
• SMIIL Gull Island Factsheet
• SMIIL Sturgeon Island Factsheet
• SMIIL Map
• SMIIL Science Poster (2022; The Wetlands Inst.)
• Dredging & Beneficial Use Timeline Poster (2022)

USACE maintains the 102-mile Delaware River main federal channel from Philadelphia to the sea. Much of the dredging work in the channel is concentrated to reaches of the river that shoal frequently. Portions of the Delaware Bay include sandy material that has been considered for beneficial use placement along bayfront communities in both New Jersey and Delaware. 

The Salem River Federal Navigation Channel, located about 54 miles from the Atlantic Ocean in New Jersey, supports U.S. Coast Guard operations, commercial and recreational fishing, and ship repair industries. The project provides for an entrance channel 16' deep and 150' wide in the Delaware River across Salem Cove to the mouth thence 16' deep and 100' wide to the fixed highway bridge in Salem. It also provides for a cutoff between the mouth and Salem. The project length is approximately 5 miles.

In 2024, USACE completed a dredging and marsh restoration project at the mouth of the Salem River in New Jersey. Work involved dredging approximately 200,000 cubic of sediment from the federal channel of the river. The predominantly fine-grained sediment will then be pumped and placed at designated locations of degraded marsh within the Supawna Meadows National Wildlife complex, which is managed by the U.S. Fish & Wildlife Service. 

The Maurice River Federal Navigation Channel, located in Cumberland County, New Jersey, supports U.S. Coast Guard operations, commercial and recreational fishing, and ship repair industries. The Congressional authorization provides for a channel 7 feet deep and 150 feet wide in Delaware Bay across Maurice Cove to the mouth; thence a channel 7 feet deep, 100 feet wide to the fixed bridge at Millville, 21.5 miles above the mouth, and then 60 feet wide to the mill dam, a further distance of one-half mile, including a turning basin 7 feet deep at Millville. The total length of the section included in the project is about 24 miles.

In 2023-2024, USACE completed a project that involved dredging more than 61,000 cubic yards of sediment from the federal channel near the mouth of the Maurice River. The sediment was hydraulically pumped to protect an area fronting the Heislerville Dike and to eroded marsh areas of Northwest Reach, both within the Heislerville Wildlife Management Area. Wetlands in this area have been severely impacted by flooding, erosion, and subsidence.  This initial sediment placement operation has been monitored and will inform future efforts to beneficially use dredged sediment.