Incident Overview

A parked, unoccupied semi-truck rolled into an open excavation at an Enbridge Line 5 valve project in Iron County, Wisconsin, on Tuesday morning, striking the pipeline and releasing natural gas liquids that enveloped the site in a visible haze, according to authorities and the company.

Enbridge, the Canada-based energy company operating the pipeline, said the incident occurred at approximately 10 a.m. Tuesday, Aug. 25, near Sitan Road in the town of Saxon, close to the Wisconsin-Michigan border. The truck had been parked when it rolled into the excavation site and hit the pipeline, causing the release of natural gas liquids, as reported by both FOX 9 and M Live Michigan.

The Iron County Sheriff’s Office said the affected section of pipeline was isolated. No injuries were reported, but nearby homes were evacuated as a precaution, and Sitan Road was closed until further notice. Authorities also established a temporary no-fly zone over the area and shut off electrical power due to safety concerns, with arrangements being made to assist residents affected by the outage.

Video from the scene, including drone footage, showed a haze and a large cloud of white vapor enveloping the construction site. Officials noted that natural gas liquid releases can involve volatile hydrocarbons capable of forming flammable vapor clouds. The public was asked to stay away from the area and follow instructions from emergency personnel.

The Iron County Sheriff’s Office did not immediately say how much product was released or how many homes were evacuated. Enbridge issued a brief statement Tuesday evening that did not go beyond the information released by local authorities, and it did not provide an estimate of the volume of product released, the duration of the pipeline isolation, or the cause of the truck's movement.

The truck’s owner and operator had not been identified as of the latest reports, and the circumstances leading to the vehicle rolling remained unclear.

Background: Line 5 and the Bad River relocation

The incident occurred at a site linked to Enbridge’s roughly $900 million project to relocate a segment of Line 5 around the Bad River Reservation in Iron County, Wisconsin. Line 5, originally built in 1953, carries crude oil and natural gas liquids between Superior, Wisconsin, and Sarnia, Ontario, including a segment that runs beneath the Straits of Mackinac in Michigan. The line has a capacity of about 540,000 barrels per day.

The project and the broader pipeline have been the subject of ongoing legal and political disputes over environmental and safety concerns. The Bad River Band of Lake Superior Chippewa has sought to remove the pipeline from its reservation, and the relocation is part of that effort.