Fresh Ideas for Recycling and Reusing Dredge Material
Problem: Maritime commerce in the Great Lakes depends on dredging, but material disposal typically costs twice as much as dredging itself. The Duluth-Superior Contained Disposal Facility (CDF) is at capacity; a new CDF would cost over $35 million. If Duluth-Superior canít supply a 20-year dredge disposal plan, the U.S. Army Corps of Engineers (USACE) would halt dredging, thereby crippling the largest commercial port in the Great Lakes.
Solution: Minnesota Sea Grant, in conjunction with Wisconsin Sea Grant and the Harbor Technical Advisory Committee, developed a strategy to partner with state agencies responsible for permitting and using dredge materials. The partnership inspired the Minnesota Pollution Control Agency, the Minnesota and Wisconsin Departments of Transportation, and the Wisconsin Department of Natural Resources to evaluate and "pre-certify" clean dredge material and to prioritize its use in state, county and city projects when possible.
These steps allow the USACE to continue dredging in the Duluth-Superior Harbor until a full strategy is adopted. Eliminating the need for a new CDF saves the port millions of dollars. The project is serving as a model for other ports throughout the U.S. Through it, new collaborative and creative recycle and beneficial-reuse scenarios for dredge material have been generated. Example: Dredge material will be used to improve the mouths of two creeks, create 85 acres of wetland, increase public access, and provide new land for a wastewater treatment facility.
Innovation and cooperation allow dredging to continue in the Port of Duluth-Superior while substantially reducing disposal costs and creating revenue and opportunities within the community.
By Sea Grant Staff