The Port of Toledo and the Maumee River Basin
If you were flying over Toledo in the summer, you would observe a city with a huge expanse of water on its doorstep and a plume of sediment flowing out into Lake Erie. As is the case with many other deep-draft ports, a river also runs through it. The Maumee River basin with nearly 80 percent of land use in agriculture is the most intensively farmed area in the entire Great Lakes Basin. Extensive soybean and corn cultivation in the 6,600 square mile Maumee basin has contributed to high sediment loads in the river and its tributary watercourses. One Maumee gauge, thirty or so miles from Toledo, indicates an annual amount of 1.3 million tons of suspended sediment.
As a result of all of this flowing soil, Toledo Harbor has large dredging needs. In recent years, the Army Corps of Engineers has removed an average of 800,000 cubic yards of sediment from navigation channels in the Maumee River and about 200,000 cubic yards in the outer harbor in Lake Erie. These amounts make the Toledo Harbor project the largest regular dredging project on the Great Lakes. The high volume of sediment, if allowed to build up, would in the short term substantially affect commercial vessel drafts and in the long run threaten the port’s existence. The port handles an average of 15 million tons of cargo a year, including coal, iron ore, grain and various general cargoes, and its activities generate more than $500 million dollars in economic activity annually with over 5,000 dependent jobs.
Dredged Material Disposal
What to do with the dredged material wasn’t always an issue, but has now become an growing concern. In the early years, sidecast dredging was a common practice where material would be removed from the Federal Navigation Channel and placed adjacent to the channel but still in the water. Large tracts of waterfront property along the Maumee River were also established as dredged disposal areas and in some cases now serve as park land for the City of Toledo. With the evolution of technology, it became possible for dredge contractors to efficiently utilize hopper dredges and remove material to designated disposal areas in Lake Erie.
In-water disposal of dredged material in the Great Lakes was commonplace prior to the late 1960’s. A hundred years of industrial activity and related pollution in port cities resulted in contaminated sediments often in harbors and navigation channels. A law passed in 1970 authorized the building of confined disposal facilities in the Great Lakes for dredged material not suitable for placement elsewhere. About half of the 4 million cubic yards of material dredged each year in the Lakes goes to CDFs including one built in the Toledo area in the mid-70’s. This amount is the approximate equivalent of 400,000 standard dump truckloads.
Since the 1970s, most of the dredged material from Toledo Harbor has been disposed of either in a CDF or at a nearby Lake Erie site. But in 1991, USEPA agreed with Ohio EPA’s determination and local citizen interests that open lake disposal should be discontinued because of toxic and phosphorous contamination concerns as well as resuspension of material from the Lake Erie site. This prospect raised a major issue. If all or even most dredged material were to be placed in existing CDFs then their capacity would be exhausted sooner rather that later. This, in turn, would require a new CDF, thus doubling local dredging costs from the $2.2 million a year now (1999). Also, as of 1996, new CDFs are to be cost- shared with a non-federal sponsor so local money would also be needed.
A Disposal Alternative for the Future
Back in 1992, a section of the Water Resources Development Act provided for the development of a Long Term Management Strategy for Toledo Harbor to deal with the disposal issue. This federal, state and local effort, through the establishment of a working group, came up with a future direction and specific strategies to manage the problem on multiple fronts. Several innovative and sensible solutions have come out of this process but it hasn’t been easy and the path is still not clear. The basic blueprint revolves around three building blocks:
- Soil conservation in the Maumee basin that would substantially reduce erosion and sedimentation;
- Measures to conserve current CDF capacity through increasing beneficial reuse of the material combined with treated sewage sludge as a manufactured soil and nourishment for wetlands along with more compaction of sediments;
- Planning for future CDF capacity that includes a CDF-type facility that would function as a shoreline protection structure and also create wildlife habitat.
The erosion and sediment reduction component has made significant progress. In 1995 the Army Corps of Engineers and the Natural Resources Conservation Service entered into a partnership for a two-year demonstration project. This was the first time that Corps dredging funds in the amount of $750,000 were directed to upland soil conservation measures. The Toledo Harbor Project entailed a program of grants to 22 basin counties for sediment projects that addressed vegetative cover, conservation tillage, structural controls such as sod waterways and numerous information/education activities. The results of the demonstration program are encouraging. The goal for the agricultural component was a 130,000 cubic yard reduction in sediment at Toledo Harbor and half of this target has been achieved. Since 1991, farmers in the Maumee basin have been increasing their use of conservation tillage practices from near 30 percent to a 60 percent rate now.
The second strategy is to find uses for material dredged from the Federal Navigation Channel and placed in confined disposal facilities. The key is to find a means of enhancing the quality of the dredged material and make it a viable product for re-use either in commercial applications or for public use. The Port Authority has taken the lead in developing a recycling alternative involving the mixing of treated municipal sewage sludge with dredged material and producing a quality topsoil. Since the late 1980’s, this effort has provided an outlet for these two so-called waste products, and provided a quality soil protective covering for use on municipal landfills. In addition to preserving space for dredged material disposal, the use of the recycled material for landfill cover has saved the City of Toledo a significant amount of public money.
The large quantity of annual dredged material also required the working group to consider capacity expansion. Currently, there are a variety of options being investigated including raising the dikes at existing confined disposal facilities and the possible construction of a new confined disposal facility which would also act as a protective barrier for a sensitive wetland area in the western basin of Lake Erie. While there is significant concern regarding the use of bottom land for new disposal areas, the construction of a new confined disposal facility which would provide multiple environmental benefits appears to be gaining governmental acceptance.
The effort to deal with the many concerns associated with dredged material disposal at Toledo, Ohio, has induced governmental agencies to take a more proactive, long term approach to the task at hand. This effort has caused various agencies to expand their view of the issue in order to come up with the most comprehensive, most environmentally acceptable and cost effective approach to dealing with a long term problem. The Toledo Long Term Management Strategy is a model of how federal, state and local governments can work together to address major dredging and sedimentation problems.
Note: This case study was prepared during the summer of 1999.
For Further Information
Toledo-Lucas County Port Authority
One Maritime Plaza
Toledo, OH 43604-1866
Phone: (419) 243-8251