This story comes from the Wisconsin News Collaborative, a partnership of public radio newsrooms including WPR, WUWM, and WXPR.
Enbridge is responding to an aquifer breach on a $1 billion project to reroute its Line 5 oil and gas pipeline in northern Wisconsin.
The breach occurred last week during installation of a new stretch of the pipeline under the Marengo River. The breach was first reported by Northern News Now.
“A flow of water was observed following the direct installation of pipe beneath the Marengo River. The observation was reported to the Wisconsin Department of Natural Resources (DNR); agency representatives have visited the site,” Enbridge spokesperson Juli Kellner said in a statement.
“Enbridge is working with the DNR and other engineering and environmental specialists to determine next steps. The water flow continues to be monitored and contained,” Kellner continued.
No details were reported on an estimated amount of water that’s been released due to the breach.
The DNR did not immediately respond to requests for comment.
This is not the first time the company has experienced aquifer breaches during construction of its pipelines. Enbridge has paid millions tied to four aquifer breaches that occurred during a project to replace its Line 3 pipeline in northern Minnesota that released hundreds of millions of gallons of groundwater.
The breach in northern Wisconsin follows numerous spills on Enbridge’s project to build a new 41-mile stretch of Line 5 in Ashland and Iron counties, including an Aug. 25 leak that released over 1.3 million gallons of natural gas liquids into the air. WPR previously reported the leak is the company’s and state’s largest oil and gas pipeline leak in Wisconsin.
The pipeline carries up to 23 million gallons of crude oil and natural gas liquids daily from Superior to Sarnia, Ontario.
In 2020, Enbridge proposed the Line 5 reroute after the Bad River Band of Lake Superior Chippewa sued the company in 2019 to shut down and remove the pipeline from tribal lands where pipeline easements had expired.
The tribe and environmental groups have mounted ongoing legal challenges to state permits for the project.
Last fall, Enbridge experts testified during a contested case hearing on permits for the project that there was zero risk of an aquifer breach.
“In view of these facts, impacts to hydrogeology—including purported risks of aquifer breach—are essentially nil. It is extraordinarily unlikely that a confining layer above an aquifer would be close enough to the fractured crystalline bedrock,” Enbridge attorneys wrote in a post-hearing brief.
Last month, DNR Secretary Karen Hyun said in response to the company’s construction of an unpermitted bypass on Line 5 that Enbridge has added to a growing list of violations that demonstrate “disregard for the environment, human health, and the statutory authority of the department.”
Environmental advocates and Bad River Tribal Chair Liz Arbuckle have called on Gov. Tony Evers and the DNR to revoke permits for the reroute.
Roughly two-thirds of the $1 billion project has already been built, and the project employs 700 workers.
Three years ago, a federal judge found the company was trespassing on the Bad River reservation and ordered Enbridge to pay roughly $5 million and shut down or reroute Line 5. The tribe and Enbridge appealed the decision.
In August, a federal appeals panel ruled that Enbridge has been trespassing and must remove the pipeline from the Bad River reservation. However, it gave the company more time to complete the Line 5 reroute.
Editor’s note: WPR’s Joe Schulz contributed to this report.
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