The web Browser you are currently using is unsupported, and some features of this site may not work as intended. Please update to a modern browser such as Chrome, Firefox or Edge to experience all features Michigan.gov has to offer.
Line 5 in Michigan
Line 5 in Michigan
Line 5 Tunnel Project Proposal Enbridge Energy Limited Partnership is currently seeking approval to build a utility tunnel and to replace and relocate the portion of the Line 5 pipeline that runs beneath the Straits of Mackinac. The proposed tunnel would house the replacement segment for the Line 5 petroleum pipeline that sits on the bottom of the Straits.
Review and permitting decisions for the proposed project involve multiple state agencies and the U.S. Army Corps of Engineers. This webpage is intended to provide an overview of the routine regulatory permitting process that the proposed project will require.
Public comment
EGLE has established a dedicated permit application email account related to the proposed tunnel project.
Find past and upcoming opportunities for public comment on the proposed Line 5 pipeline and tunnel.
Involved agencies
Michigan Public Service Commission
In December, 2023, the MPSC approved Enbridge’s application to replace and relocate the segment of Line 5 crossing the Straits of Mackinac into a tunnel beneath the Straits
Dept. of Environment, Great Lakes, & Energy
EGLE evaluates pipeline projects that impact water resources; Enbridge has submitted permit applications for work within wetland areas, water discharges and submerged lands
Mackinac Straits Corridor Authority
MSCA is responsible for overseeing construction and operation of a tunnel in bedrock beneath the waters of the Straits of Mackinac and will own the tunnel after its construction
US Army Corps of Engineers
USACE is conducting an independent review of the proposed Line 5 pipeline tunnel project which will inform its permit decision on Enbridge’s application with them