Claybanks, Mio, Michigan
The Claybanks site, located approximately 2 miles downstream of Mio in Oscoda County, MI, once contributed an estimated 262 tons of sediment to the Au Sable River Watershed.
On this stretch of river, there is natural erosion of the high sandy bluffs along the streambank. The erosion of the Claybanks bluff can be traced to numerous causes. In addition to the small amount of erosion that naturally occurs on high bluffs and the outside of river bends, the erosion of this site has been exacerbated by human access issues. It was reported that erosion rates began to increase as recreational tubers found an interesting opportunity to run up the bank and slide down to the river.
Increased Erosion Rates
As the recreational traffic increased, the vegetation was damaged to the point it could no longer stabilize the sandy topsoil. The topsoil began to erode exposing the underlying clay layer. This made the 50ft bluff more slick, which invited more human traffic. People carried their canoes up the bluff and rode them down to the water. There was also a large tree at the base of the slope which provided a jumping platform for recreational boaters.
The total stream distance considered part of the erosion problem increased to over 1200 linear feet, nearly a quarter of a mile, with the most intense erosion occurring along a 250 ft stretch.
Addressing the Issues: Restoration Activities
 Huron Pines addressed two factors to reduce the erosion of the Claybanks site. First, further human access to the site was curtailed to prevent the root cause of the soil losing stability. Secondly, since the topsoil was eroded and deposited in the adjacent stretch of river, there was a concerted effort to add soil back to the site to nourish plantings during the stabilization project.
Large Wood Debris was placed along the water’s edge on the Claybanks site. This part of the project,, served several purposes. Most importantly, they prevented access to the bank by recreational boaters. Secondly, the trees acted as buffers to the incoming water energy. Slowing the water along the shoreline decreased the erosion potential of the river’s velocity. Finally the trees replenished habitat along the bank that was degraded by the sedimentation that follows bank erosion.
 Coconut fiber logs were also placed from the water's edge to the height of the floodplain on the opposite bank. These coir logs will provide a “soft” wall to protect the bank from high water flows and to hold back any loose sediments. Nearly 600ft of coir logs were installed. In addition to the logs at the toe of the slope, several logs were placed at logical breaks in slope as you head up the bank. These breaks may be where a seep exits the bank, or a slump has created a small shelf or terrace.
In addition, over 10 cubic yards of field stone were placed at the outlet of a drainage culvert to prevent further incising activity from the flowing water. The invert of the culvert also received attention. Two cubic yards of material were placed and compacted over the pipe. This will ensure that water goes into the pipe and not over, preventing erosion around the structure.
Next, mulch fabric was placed over the soil and pinned down with landscaping staples. Finally, native vegetation was planted.
Project Partners and Funders
Michigan Department of Natural Resources
Michigan Fly Fishing Club
US Forest Service
US Fish & Wildlife Service
William B. Mershon Chapter of Trout Unlimited
For more information on the Claybanks project, please contact Patrick Ertel.
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