The US Army Corps of Engineers has approved an application from energy developer Enbridge Inc. to move a section of its Line 5 pipeline around the Lake Superior Chippewa Bad River Band Indian Reservation in northern Wisconsin.
The decision concludes a more than four-year federal review under the federal Clean Water Act, Section 404, and the Rivers and Harbors Act, Section 10. The agency said it evaluated the application “in accordance with all applicable tribal and environmental consultation requirements” before issuing the permit.
RELATED
The Corps of Engineers publishes a long list of project permit applications that can be fast tracked
Enbridge will replace about 20 miles of the existing line, including the 12 miles through the reservation, with a new 41-mile, 30-diameter segment through Ashland, Bayfield and Iron counties. The corridor crosses forests, wetlands and the Bad River watershed, where glacial soils and high groundwater complicate construction.
Federal and state reviews cite erosion and settlement risks in peat and silt deposits; Enbridge plans trench boxes, mats and horizontal directional drilling in wetlands and stream crossings to limit disturbance.
Environmental risks and tribal opposition
“The Wisconsin Segment of Line 5 relocation project will not have measurable impacts on Bad River Band water quality standards,” Enbridge Environmental Director Joe McGaver told regulators, citing erosion control and post-construction monitoring plans.
Ray Wuolo, a hydrogeologist with Barr Engineering, added that hydrologic connectivity between the route and the reserve “is indirect, except at stream crossings,” and that any effects would be localized and short-term.
Foam trench breakers are being installed along Enbridge’s Line 5 oil pipeline corridor to prevent erosion and control groundwater flow, one of several stabilization techniques cited in the company’s plan to limit wetland disturbance during the relocation of the Wisconsin segment.
Photo courtesy of Enbridge Inc.
However, the Bad River Band technical documents themselves challenge this conclusion. In its EPA 401(a)(2) rebuttal comments to the US Environmental Protection Agency, the tribe wrote that Enbridge’s model “does not demonstrate the absence of a connection between the diversion footprint and reservoir waters” and warned that “wetland losses and increased runoff could degrade water quality conditions that support wild rice.”
A 2025 mapping study by the Indian Great Lakes Fish and Wildlife Commission found that updated lidar data expanded mapped wetlands in the project area by more than 200 percent, suggesting greater hydrologic connectivity than Enbridge’s original analysis.
Enbridge disputed those findings in its formal environmental filing with federal and state regulators, where Wuolo said the modeling showed “no direct surface water connection between the diversion footprint and the Bad River Reserve, except at controlled stream crossings.”
Wuolo told the Corps and the Wisconsin Department of Natural Resources that construction impacts “will be localized and short-term, generally measured in days,” and that post-construction restoration will “return pre-construction hydrology in a growing season,” according to Enbridge’s regulatory filing.
Michels Pipeline Inc., a division of Brownsville-based contractor Michels Corp., will build the new segment under a project-work agreement signed with four unions in 2022. Enbridge has not provided updated cost or schedule details; state filings previously put the investment at about $450 million.
ENR requested additional project information from Enbridge, but did not receive a response by press time.
RELATED
Michigan Court of Appeals Affirms State Approval for Line 5 Pipeline Solution
Federal documents show the project will permanently fill 0.02 acres of wetlands and temporarily disturb approximately 101 acres. The Wisconsin department’s final environmental impact statement deemed the relocation “the least environmentally harmful practicable alternative” and issued a water quality certification in November 2024, now under court challenge.
The Bad River Band continues to oppose the project, saying the relocation does not eliminate environmental or treaty rights risks. ENR’s attempts to reach the tribe for more details were unsuccessful before press time.
“The continued operation and relocation of Line 5 threatens our waters, wild rice and treaty-protected resources,” the tribe wrote in 2022. The band has yet to issue a formal statement on the Corps’ approval, but has indicated it will continue to seek legal recourse.
Line 5 has been in operation since 1953, transporting up to 540,000 barrels per day from Superior, Wisc., through Michigan to Sarnia, Ont. Enbridge says the Wisconsin diversion will reduce risk by removing the land line from the reserve while maintaining regional power supply.
“The Corps’ decision demonstrates our commitment to balancing national energy needs with environmental protection and consultation with tribal nations,” said the St. Paul in his leave announcement.
