Paper Highlights Benefits Of Sustainable Dredging
Sustainable dredging in rivers is the focus of a new paper published in the January 2024 issue of the Western Dredging Association’s (WEDA) Journal of Dredging.
Titled “Sustainable Dredging Practices Produce Multiple Benefits on the Ohio and Kanawha Rivers,” the manuscript is an extension of a paper presented by Andrew McQueen at the 2023 WEDA Dredging Summit and Expo, according to an editor’s note. The paper is a result of a study funded by the U.S. Army Engineer Research and Development Center (ERDC) Dredging Operations and Environmental Research Program.
The article describes three Huntington Engineer District dredging projects: at Bonanza Bar and Robert C. Byrd Locks and Dam on the Ohio River and at Winfield Locks and Dam on the Kanawha River, seeking to make beneficial use of dredged materials to improve the habitat of protected mussels that live in the rivers while also providing other benefits.
Projects like these are key, according to the article, as the Corps of Engineers seeks to increase projects with beneficial use of dredged materials to 70 percent of all projects by 2030 instead of the current 30 to 40 percent beneficial use. To increase the beneficial use and overcome any challenges, it is important to see how such materials have been successfully used already, the article authors explain. They also note that little study of the beneficial use of dredged materials has taken place in river environments.
At each of the three project sites, the study reviewed historical dredging, including costs and survey data, mussel surveys, historical photos, navigational charts and drone and satellite imagery as well as water quality monitoring data, acoustic Doppler data and observations from multiple site visits by ERDC staff. Study authors ultimately determined that the benefits of placing dredged material included creating side channel habitat, increasing native mussel populations nearby and just downstream of placed sediment and increasing efficiencies within the dredging program.
Specifically, restoring the historic Bonanza Bar island footprint at side channel habitat has allowed for more efficient dredge placement; reduced timing, frequency and cost of dredging in the navigation channel; and provided valuable ecological habitat and recreational opportunities.
Innovations in managing water operations at Robert C. Byrd Locks and Dam during dredge placement activities allowed the district dredging program to meet goals of supporting safe and reliable waterborne transport while also protecting sensitive mussel bed habitat, the study authors said. Additionally, advanced environmental monitoring tools at the site allowed for real-time monitoring of turbidity and sedimentation, improving risk communication and management for the mussel beds.
Finally, beneficial use of dredged sediments at Winfield Locks and Dam helped improve habitat and to increase downstream populations of mussels. The project determined that placing dredged materials in the river to improve the sediment characteristics conducive for mussel beds is a preferred placement strategy recognized by both state and federal wildlife agencies at this location.
Ultimately, the article concludes that by “engineering with nature,” including leveraging natural processes, producing efficiencies, broadening existing benefits and using meaningful science-based collaboration, agencies can achieve shared goals.
Data and lessons learned from projects like these may ultimately be applied elsewhere to help development of sustainable dredging practices, providing inspiration for future projects.
The complete article is available at www.westerndredging.org/journal.