DECEMBER 10, 2025 – The Mississippi River’s newest addition is making positive waves. A man-made island is being constructed to protect and preserve critical habitats while enhancing resilience along the waterway.
Nick Castellane, project manager, shared insights into the Pool 2 protective island and collaborative efforts between the Corps and its contractors to build the island upstream of Lock and Dam 2 in Hastings, Minnesota.
“The goal of the protective island is to shield the existing embankment from wind, wave erosion and ice buildup in the spring melts, while also protecting the river’s ecosystem,” Castellane said.
The protective island project is critical to safeguarding the 3,250-foot-long earthen embankment on the upstream side of the river. Originally constructed in 1930, the embankment has experienced erosion over time due to harsh weather conditions, lack of vegetation and high-water events. The new island will act as a buffer, reducing the impact of wind and waves while supporting the river’s ecological health.
The mile long island will use over 300,000 cubic yards of dredged material, or river sand, out of the Mississippi River maintaining the crucial channel for the navigation industry.
“The contractor mechanically dredges sediment and transports it to a transfer site,” Castellane said. “From there, the material is loaded onto a barge, placed in a hopper, and piped over to the island. Once it’s expelled, the contractor uses an excavator and bulldozer level and compact the material to shape the island.”
One of the standout features of the project is its sustainable approach, Castellane said. “We’re utilizing material directly from the Mississippi River channel,” he said. The island will include a variety of features, such as areas at different elevations above the typical pool level to provide habitat benefits. These features include tall grasses, tree plantings, wetlands, rock structures, and an overwintering fish habitat.
“Another outgrowth of this project is creating new habitats with nearly 16 acres of vegetation on top of the island and an aquatic overwintering area,” said Thomas Reinhardt, construction engineer.
Due to the material being taken directly from the river to its destination on the island, the contractor maintains consistent communication with Corps officials, working efficiently 24 hours a day while keeping safety a top priority, he explained.
“This project is vital to navigation because we need to maintain the pool elevation,” Castellane said. “The embankment structure is critical to our core mission of maintaining the 9-foot navigation channel. By using material from the channel, we’re not only building the island but also ensuring the navigation channel remains at the required depth to support the transportation industry.”
In order for these benefits to come to fruition by 2027, partnership and coordination across multiple entities is essential.
“The project’s success depends on the combined efforts of engineers, environmental experts, and local stakeholders working together to ensure the island fulfills its protective and restorative goals,” Reinhardt said.
The Mississippi River plays a key role in commerce, with approximately 10 million tons of cargo passing through the lock and dam annually. “Materials like soybeans, corn, petroleum products, concrete, and more are transported up and down the river,” Castellane said. “This project ensures that the river remains a reliable resource for both navigation and the environment.”
Story by Elizabeth Stoeckmann
U.S. Army Corps of Engineers, St. Paul District