Fresh, July 9, 2024: Hundred Years’ Worth of Sediment Floods Blue Earth River After Minnesota Partial Dam Failure

July 9, 2024

Fresh is a biweekly newsletter from Circle of Blue that unpacks the biggest international, state, and local policy news stories facing the Great Lakes region today. Sign up for Fresh: A Great Lakes Policy Briefing, straight to your inbox, every other Tuesday.

— Christian Thorsberg, Interim Fresh Editor

This Week’s Watersheds

About 1,200 gallons of an unknown oily substance have been removed so far from the Flint River following a spill in late June.
The failure of a dam following a deluge in Waupaca County, Wisconsin, prompted evacuations and a boil-water advisory.
Nearly 12 million cubic yards of sediment concentrated with agricultural runoff has flowed into the Blue Earth River in southern Minnesota after a partial dam failure.
Lake Michigan’s first international sea cargo container terminal has been approved for construction in northwest Indiana.

The FishPass project in Traverse City, Michigan — which will replace a dam with a fish-friendlier channel — received $1 million in state funding.

“We are thrilled to receive this investment. While FishPass is in Traverse City, it is a project for everyone – having a positive impact all over the Great Lakes and beyond – and we are honored to accept this support from the State of Michigan.” — Marc Gaden, executive secretary of the Great Lakes Fishery Commission.

One million dollars from the 2025 Michigan state budget will support the replacement of the aging Union Street Dam with FishPass — a barrier that allows fish like sturgeon and trout to swim through, while blocking invasive species such as sea lamprey. The project is the culmination of more than two decades of work to reconnect the Boardman-Ottaway River with Lake Michigan.

The project is being completed in two parts. FishPass’s “wet” component, which includes in-stream fish passage and dam replacement, is expected to be completed in 2026. Roughly one year later, the project’s “dry” component — featuring an educational center and naturalized river channel elements — will be fully opened, WWTV-TV reports.

Fresh from the Great Lakes News Collaborative

‘Rock Snot’ threatens Michigan’s aquatic ecosystems — Michigan Public
A Symbol of Survival: Red Pine Peels and Ojibwe Canoe Factories — Great Lakes Now
Experts predict moderate Lake Erie toxic algae bloom — Bridge Michigan
Ontario has ‘no commitment to a timeline’ for finishing Highway 413, document shows — The Narwhal

Bridge Michigan, Circle of Blue, Great Lakes Now at Detroit Public Television, Michigan Public and The Narwhal work together to report on the most pressing threats to the Great Lakes region’s water. This independent journalism is supported by the Charles Stewart Mott Foundation. Find all the work here.

Partial Failure of Rapidan Dam Sends Sediment Rushing Downstream

Roughly 11.6 million cubic yards of polluted sediment was released into the Blue Earth River in recent weeks in southern Minnesota, following the partial failure of Rapidan Dam, Minnesota Public Radio (MPR) reports. The sediment is saturated with phosphorus and nitrogen from decades of agricultural runoff.

The dam is still standing, but the river eroded the bank and cut a new course around the structure.

It will take a few years, officials say, before the event’s environmental impacts are determined. But releasing a century’s worth of sediment downstream is likely to cover shallow habitat important to fish and macroinvertebrates, scientists told MPR.

Large volumes and fast flows contributed to the dam’s collapse. Formerly a hydropower generator, it had been inactive since 2019. But officials at the time elected to keep it in place, rather than replace it, in large part because of the cost and complication of dealing with the sediment.

In the News

Flint River: Officials are still determining the cause of a June 25 spill in the Flint River as cleanup efforts continue, Michigan Public reports. Thus far, roughly 1,200 gallons of an “oily-watery mix” have been recovered from its waters. The unknown substance likely leaked into the river through a storm drain near the University of Michigan-Flint, and samples have been taken to a laboratory for testing. According to a City of Flint press release, this is the fourth spill in the river in the last 12 months.

Waupaca County: The central Wisconsin community is still recovering after up to six inches of rain fell last Friday, Wisconsin Public Radio reports. Residents — including those at a local nursing home — were evacuated when the Manawa Dam, built in 1920, was breached due to erosion around the structure. But the dam remained intact. As of the weekend, more than 1,400 people were under a boil-water advisory for their drinking water.

Looking Ahead

Ports of Indiana: A proposal for Lake Michigan’s first international sea cargo container terminal has been approved by the U.S. Customs and Border Protection. According to the Ports of Indiana, “this would create the only all-water container route for ocean vessels to serve the greater Chicago metropolitan area via the Great Lakes.” Presently, all containers that are shipped through the area are moved by train or truck. The facility is expected to be built by 2025 at the Burns Harbor terminal in northwest Indiana, the country’s 25th largest port, which handles 25 million tons of cargo per year.

Upcoming Events

July 18 — Great Lakes Seminar Series with Jeffrey Freymueller, Geodetic Observations of Water Mass Changes in the Great Lakes Basin — learn more

July 30 — Due date for nominations to serve on the EPA’s Great Lakes Advisory Board — learn more

August 9 — American Great Lakes Ports Association 2024 Annual Conference — learn more

Other News

Walleye: By a vote of 94 to 2, the Ohio House has named the walleye its state fish, the Columbus Dispatch reports. With the announcement, Indiana and Iowa remain the only states without a state fish.

PA AIS App: Pennsylvania Sea Grant, through funding from the U.S. Fish and Wildlife Service and Great Lakes Restoration Initiative, released a new app that trains citizens to identify aquatic invasive species.

Christian Thorsberg

Christian Thorsberg is an environmental writer from Chicago. He is passionate about climate and cultural phenomena that often appear slow or invisible, and he examines these themes in his journalism, poetry, and fiction.