Dredging crews will return to the Grand Traverse Harbor in Houghton County this summer as efforts continue to save Buffalo Reef from being covered by stamp sand mining waste, Michigan’s Department of Natural Resources (DNR) said .
Over the past roughly 100 years, historic copper mine tailings from the Wolverine and Mohawk mines – called stamp sands – were deposited at a milling site along Lake Superior, located in the community of Gay in Keweenaw County.
Since that time, the stamp sands have been moved by winds and waves south down the shoreline roughly five miles, inundating natural sand beach areas and threatening to cover spawning habitat and recruitment areas important to Lake Superior whitefish and lake trout associated with Buffalo Reef.
The natural reef is located beneath the waters of Grand Traverse Bay.
To help combat the threat posed to the reef and the harbor by the migrating stamp sands, various dredging efforts have taken place over the past few years, including removal of a 25-foot-high bank from the Lake Superior shoreline in 2019.
Harbor dredging efforts by the Keweenaw Bay Indian Community and others have kept the waterway open for fishing, boating and other recreation.
Meanwhile, the multi-agency Buffalo Reef Task Force continues to move forward with a long-term strategy to combat the stamp sands problem at the Grand Traverse Bay Harbor and Buffalo Reef, DNR said.
Over the past several years, the task force evaluated the feasibility and cost estimates of more than a dozen potential ideas for disposal of dredged stamp sands removed from threatening the natural 2,200-acre reef.
The task force decided ultimately to construct an upland facility for disposal of stamp sand removed from the Lake Superior shoreline. In addition, a 2,000-foot-long jetty would be constructed to intercept the stamp sand as it migrates south.
“ Geotechnical work for the proposed jetty was completed last fall, design is expected to be completed in three months ” said Jay Parent , district supervisor of the Michigan Department of Environment, Great Lakes, and Energy’s Water Resources Division in Marquette. “ Geotechnical work and design of the proposed upland stamp sands placement facility is going on right now.”
The most recent cost estimate for completing the long-term project is $2.1 billion over the length of its timeline.
Dredging the harbor at the mouth of the Traverse River is needed to continue the broader efforts to save and restore Buffalo Reef, but it will have other immediate impacts as well, DNR concluded.