Supplemental Draft Environmental Impact Statement Available for Public Review Enbridge Line 5 Tunnel Project

Supplemental Draft Environmental Impact Statement Available for Public Review Enbridge Line 5 Tunnel Project The United States Army Corps of Engineers (USACE), Detroit District, announces the availability of a Supplemental Draft Environmental Impact Statement (EIS) to the Enbridge Line 5 Tunnel Project Draft EIS, which was published in May 2025. The Supplemental Draft EIS identifies and addresses potential environmental impacts from the Horizontal Directional Drilling (HDD) Installation Alternative, an alternative to the proposed Tunnel Project. The public is invited to review and provide comments on the Supplemental Draft EIS until the end of the public comment period on December 5, 2025. The Supplemental Draft EIS is available online at www.line5tunneleis.com. Comments received or postmarked on or before the expiration date of December 5, 2025, will be considered. USACE will be hosting a virtual public meeting on December 3, 2025, 1 p.m. to 4 p.m. EST. Meeting access information will be posted to the project website at https://www.line5tunneleis.com/public-meeting-information/. The public may submit written comments online at www.line5tunneleis.com or by mail to: Line 5 Tunnel EIS, 6501 Shady Grove Road, P.O. Box 10178, Gaithersburg, MD 20898. Pursuant to Section 10 of the Rivers and Harbors Act of 1899 (Title 33 United States Code (U.S.C.) Section 403) and Section 404 of the Clean Water Act (Title 33 U.S.C. Section 1344), Enbridge Energy, Limited Partnership (the Applicant) applied to USACE for a Department of the Army permit for structures and/or work that may affect navigable waters of the United States (U.S.) and discharges of dredged or fill material into waters of the U.S. associated with its proposed Tunnel Project (identified as the Applicant's Preferred Alternative in the May 2025 Draft EIS) (File LRE-2010-00463-56-A19). USACE prepared this Supplemental Draft EIS because it determined an alternative to the Applicant's Preferred Alternative previously considered in the May 2025 Draft EIS but eliminated from detailed analysis because it was considered infeasible, is now feasible due to advances in technology and meets USACE's established screening criteria for alternatives. USACE will carry forward the HDD Installation Alternative for detailed analysis in its EIS to meet its NEPA requirement to evaluate reasonable alternatives to the project under consideration. The HDD Installation Alternative would utilize the intersect method to install a replacement Line 5 pipeline segment via HDD in bedrock underneath the lakebed of the Straits of Mackinac in Michigan. The Supplemental Draft EIS describes the HDD Installation Alternative in detail, the existing environment that could be affected, the potential impacts resulting from the alternative, and potential best management practices and impact reduction and mitigation measures. The Supplemental Draft EIS assesses potential impacts on environmental resources including geologic resources, water resources, biological resources, cultural resources, air quality, noise and vibration, transportation and navigation, land use and recreation, aesthetics, soils, socioeconomics, and reliability and safety. November 13 2025 LPET0406027