‘Cause for alarm’: Encroaching stamp sands threaten northern Keweenaw Bay fisheries
HOUGHTON — Stamp sands remain a threat to the Keweenaw Bay and Buffalo Reef.
“There is cause for alarm,” said Michigan Tech biology professor Charles Kerfoot.
Kerfoot spoke to Tech students and faculty Monday, giving an update on the situation and potential problems. He has been working to come up with a solution to the encroaching stamp sands.
Created from the residue of smelting copper, stamp sands were produced when rocks were crushed to separate copper from the surrounding rock. Typically, the by-product was dumped into nearby bodies of water.
As Kerfoot explains, mining companies didn’t worry about the long-term ecological impacts when mines were in operation, leaving future generations to deal with the situation.
At the moment, stamp sands are threatening to cover the Buffalo Reef and causing blockages at the mouth of the Traverse River. Often despite efforts to contain them.
The Buffalo Reef is a fishing hotspot and spawning ground for whitefish and lake trout, home to 33 percent of fish caught in Keweenaw Bay. Once stamp sands move into an area, it becomes toxic and unlivable for most lifeforms. The high copper-particle content alone kills plant and algae, destroying the food chain.
The rate of stamp sand erosion is fairly consistent, Kerfoot said. Migrating at a rate of 26 feet a year, the problem is where it spreads. If the situation remains unchanged, 60 percent of the reef could be covered in an inch of stamp sand in 10 years.
If a total ecosystem collapse were to occur, it would cost the local economy an estimated $1,679,383 each year, Kerfoot said, in loss of jobs, recreational fishing and commercial fish sales, and also require artificial restocking.
“It’s really serious what’s going on both to invertebrates and fish,” he said.
Containing stamp sands is not so simple. The Traverse River mouth was almost blocked by shifting stamp sands after a single storm and high water.
“They had just cleared out all the stamp sands…and poof. This is a challenge,” Kerfoot said.
Kerfoot offered a few possible solutions. Stamp sands have been repurposed for use in road work, deposited back into mines or undergone strategic dredging.
“There is a sense of urgency,” Kerfoot said.
Moving forward, further solutions will have to be worked out to keep the Keweenaw Bay area healthy, he said.