COHASSET — An estimated 1 million gallons of coal ash wastewater has spilled at Minnesota Power's Boswell Energy Center in Cohasset after a leak was detected in a pipe on Tuesday, July 16.
According to the Minnesota Pollution Control Agency, the leak likely began from an underground pipe and surfaced where the pipe extends above the ground. Minnesota Power reported a loss of pump pressure caused the leak, MPCA said in a statement Wednesday.
Minnesota Power said the pipe transfers the wastewater from an inactive pond to the plant. As soon as the spill was detected, crews worked to contain the leak from surface waters.
The wastewater was released into the soil and flowed to Black Water Creek and into Blackwater Lake, an impoundment of the Mississippi River and part of the Pokegama Reservoir system.
It is unknown how much of the spill reached the lake.
Minnesota Power reported the incident at 11:30 a.m. Tuesday. It said the spill was discovered 15 minutes earlier but was no longer active at the time of discovery. A Wednesday statement from the company said the leak is contained.
MPCA and U.S. Environmental Protection Agency staff met with Minnesota Power and its environmental contractor at the site Tuesday evening.
The company believes no drinking water was affected but it is continuing water testing and monitoring to determine impacts to the aquatic environment, Minnesota Power spokesperson Amy Rutledge said in a Wednesday email to KAXE.
Minnesota Power said it is working closely with state and federal agencies to identify and assess the spill's impacts. MPCA said it continues to assess the situation and determine strategies to minimize impacts to the creek and lake.
Funding for this environmental story was provided by the Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR).
-
The Clean Water Legacy Partners Grants Program funds projects proposed by tribal entities, tribal governments and nonprofit organizations through the program.
-
The Minnesota Court of Appeals heard oral arguments at Pequot Lakes High School on Sept. 22, 2026, in front of 300 upperclassmen.
-
Federal safety net program cuts are on the minds of economists with new data on last year's median incomes, official poverty rate and holistic poverty rate.
-
Plus: Early voting opened Sept. 18, 2026, for all eligible voters Minnesota; and Northern Minnesota tribes are among groups receiving Clean Water Legacy grants.
-
The Bemidji Fire Department responded to a mobile home fire in Northern Township on Sept. 20, 2026. One occupant had escaped while another was unaccounted for at the time of the report.
-
The Iron Range offers a window into communities reckoning with how their identities must change for the betterment of future generations as schools increasingly collaborate.This reporting is part of a collaboration with the Institute for Nonprofit News' Rural News Network and Big Local News at Stanford University, with data journalist Cherry Salazar’s analysis helping anchor the reporting. Six nonprofit newsrooms were involved: BenitoLink, KAXE, Mat-Su Sentinel, Mississippi Today, Oxford Free Press and The Texas Tribune. Support from the Walton Family Foundation made this project possible.