State agency continues review of Line 5 replacement section

Cross-section animation of Great Lakes Tunnel

Hearings to examine new testimony

April 12, 2023

What’s new

The Michigan Public Service Commission (MPSC) is holding a hearing this week regarding Enbridge’s request for approval to replace the existing Line 5 dual pipelines with a new, single replacement segment located within the planned Great Lakes Tunnel Project beneath the Straits of Mackinac.

The MPSC hearing is streaming live starting now through April 14. The MPSC is hosting the hearing to allow for cross-examination of witnesses who filed testimony in response to the MPSC’s July 2022 order seeking additional information concerning the proposed replacement.

Why it matters

In considering Enbridge’s request to replace the existing dual pipelines with a new Line 5 replacement segment, the MPSC in its July 2022 order asked the parties to provide additional information. While the MPSC proceeding does not concern the Great Lakes Tunnel itself, the MPSC asked for additional information on the Tunnel engineering and design, as well as on the existing dual pipelines.

The MPSC’s approval will allow Enbridge to construct the Line 5 replacement segment within the Great Lakes Tunnel.

“The Line 5 replacement segment will enhance safety of the Great Lakes, eliminating the possibility of an anchor strike” said Kate Houchard, Enbridge’s operations manager for the Great Lake Region. “The Tunnel that will house the replacement segment will provide additional containment to prevent a potential release into the Great Lakes.”

Separately, Enbridge is obtaining the approvals needed to construct the Tunnel. In January 2021, the Michigan Department of Great Lakes and Energy issued the required state permits for the Tunnel. Enbridge’s application before the U.S. Army Corps of Engineers is pending.

“We welcome the MSPC’s diligence in its review of our request to replace the existing dual pipelines within a single replacement pipe, placed in an underground Tunnel,” said Houchard. “This region relies on Line 5 in the Straits, so Enbridge has been equally diligent, working with world-class engineers, and safety and environmental professionals to develop the replacement project.”

Background

Enbridge has been working on replacing the existing dual pipelines since first signing the 2018 agreement with the State of Michigan to build the energy infrastructure project.