What’s Next for Line 5?
James Hill
Line 5 is an oil and liquefied natural gas (LNG) pipeline operated by Canadian energy company Enbridge; a key segment was built on the lakebed between the southern and upper peninsulas of Michigan in the straits of Mackinac in 1953.[1] The pipeline was meant to last for only 50 years but continues to transport hydrocarbon products across Canada and into the US.[2] In 2018, Enbridge proposed a project to update the pipeline by burying it in a tunnel underneath the lakebed.[3] In response, tribal governments, environmental groups, and citizens throughout Michigan called to “shut down line 5” due to concern over the continuing practice of transporting hydrocarbons through the straits and the potential devastating impacts that an oil spill would have on Lake Michigan and Huron if the pipe ruptured.[4] In a study of worst-case oil spills in the Straits, David Schwab at the University of Michigan Water Center concluded “that more than 1,000 km of Lake Huron-Michigan shoreline and specific islands are potentially vulnerable to an oil release in the Straits.”[5]
- Background of Line 5 Litigation
The Michigan Public Service Commission (MPSC) has the power to regulate transportation of “crude oil or petroleum, or any of the products thereof, or carbon dioxide substances, by or through pipe line or lines.”[6] The MPSC issued a 359-page opinion and order in 2023 granting Enbridge conditional approval of the tunnel project, stating that there was a “public need for the products shipped through the Line 5 segment.”[7] That decision was subsequently challenged by tribal governments and environmental organizations on the grounds that the decision incorrectly determined if there was public need for the project, violated the Michigan Environmental Protection Act (MEPA), and was against the public trust doctrine.[8]
There are other former and ongoing lawsuits against Enbridge and Line 5 besides the challenge to the MPSC decision. First, a Wisconsin federal district court issued a court order to shut down Line 5 in three years (by June 2026), finding that Line 5 is trespassing on land belonging to the Bad River Band of Lake Superior Chippewa.[9] Second, Michigan Governor Gretchen Whitmer ordered Enbridge to shut down Line 5 by May 2021, but Enbridge defied that order and continues to pump oil and liquefied natural gas through the pipeline.[10] The case over this state order remains pending in Ingham County Circuit Court after being remanded by the U.S. Court of Appeals for the Sixth Circuit.[11]
- The Michigan Court of Appeals affirmed the MPSC’s decision and stunted efforts to remove Enbridge’s presence in the straits entirely.
On February 19, 2025, the Michigan Court of Appeals published an opinion on this litigation by tribal governments and environmental groups challenging the MPSC decision that granted Enbridge a permit to move forward with the proposed relocation project.[12] The court held that there was “no basis upon which to reverse MPSC’s final order” because the MPSC sufficiently showed that Enbridge’s “authority to operate Line 5 has already been established, and the public will be served by the Replacement Project because of the risk posed by the continued use of the dual pipelines.”[13] The court provided that the standard of review for MPSC decisions was whether the Commission failed to follow a statutory requirement or abused its discretion in the exercise of its judgment.[14] Past precedent suggests that considerable respect is given to decisions from the MPSC, and this rather deferential standard of review results in a high bar to find abuse of discretion.[15]
The intervenors argued that the MPSC surpassed this bar both by acting inconsistently in justifying the permit and failing to consider the public trust doctrine.[16] According to the court, for the MPSC to determine public need for the project, it should have determined public need based on the project that Enbridge applied for, not the entirety of Line 5.[17] However, the MPSC considered the consequences of a Line 5 shut down in full in its 2023 decision.[18] The court resolved this by referring to an earlier MPSC order from April 2021 that was incorporated into the 2023 order, finding that the “already-established public need for Line 5 was a piece of the puzzle demonstrating a need for the Replacement Project.”[19] The public trust doctrine is a common law doctrine saying that “the state owns and holds the waters and bottomlands of the Straits and Great Lakes in public trust.”[20] The Michigan Supreme Court has interpreted this to entail an “obligation to protect and preserve the waters of the Great Lakes and the lands beneath them for the public.”[21] The court in this case concluded that the MPSC is a “creature of the legislature” and thus has no common law powers unless they are statutorily provided by the legislature.[22]
- What’s Next?
Recently, one of the environmental groups, For Love of Water (FLOW), announced an appeal to the Michigan Supreme Court.[23] The Court of Appeals judgment weakened the public trust doctrine, or at least made it clear that if the doctrine is not codified in some way by the legislature, then decisions from agencies like the MPSC are immune from public trust considerations.[24] FLOW plans to center its appeal on this contention, arguing that based on Michigan Supreme Court precedent, agencies like the MPSC need to consider the fundamental obligations under the public trust doctrine.[25] Another potential concern is the recent executive order by the Trump Administration declaring a national energy emergency, which prompted the US Army Corps of Engineers (USACE) to identify projects potentially slated for emergency approval.[26] The Line 5 tunnel project was one of the projects listed, and the MPSC permit was conditioned on Enbridge receiving approval from USACE.[27] The risk of an environmental disaster in the straits of Mackinac remains present so long as Line 5 continues operation. The recent decision by the Michigan Court of Appeals, along with an executive order meant to expedite project approvals, is an unfortunate step towards ensuring that the pipeline remains operational. The Michigan Supreme Court can reaffirm the public trust doctrine in Michigan by ensuring that agencies such as the MPSC fully consider the impact of their decisions on the public trust.
[1] Line 5: Overview, Michigan Department of Environment, Great Lakes, and Energy, https://www.michigan.gov/egle/about/featured/line5/overview (last visited March 20, 2025).
[2] Enbridge Line 5 Pipeline in the Great Lakes, For Love of Water, https://forloveofwater.org/about-line-5/ (last visited March 20,2025).
[3] Id.
[4] Id.
[5] David Schwab, Statistical Analysis of Straits of Mackinac Line 5: Worst Case Spill Scenarios 10 (2016).
[6] Mich. Comp. Laws § 483.1 (1929).
[7] In re Enbridge Energy, Ltd. Partnership, Order of the Public Service Commission, (Dec. 1, 2023) (available at https://adms.apps.lara.state.mi.us/Mpsc/ViewCommissionOrderDocument/26687), at 302 (hereinafter Order of the Public Service Commission).
[8] In re Enbridge Energy to Replace & Relocate Line 5, No. 369156, 2025 WL 554844 (Mich. Ct. App. 2025).
[9] Bad River Band of Lake Superior Tribe of Chippewa Indians of Bad River Reservation v. Enbridge Energy Co., Inc.,No. 19-CV-602-WMC, 2023 WL 4043961 (W.D. Wis. 2023).
[10] State of Michigan, Office of the Governor, Department of Natural Resources, Notice of Revocation and Termination of Easement (November 13, 2020).
[11] Nessel on behalf of People of Michigan v. Enbridge Energy, LP, 104 F.4th 958 (6th Cir. 2024).
[12] In re Enbridge Energy, 2025 WL 554844.
[13] Id. at *11 and *14.
[14] Id. at *10, (citing In re MCI Telecom Complaint, 596 NW2d 164 (Mich. 1999)).
[15] Id.
[16] Id.
[17] Id. at *12
[18] Order of the Public Service Commission, supra note 7, at 302.
[19] In re Enbridge Energy, 2025 WL 554844 at *13.
[20] Id.
[21] Glass v. Goeckel,703 NW2d 58(Mich. 2005).
[22] In re Enbridge Energy, 2025 WL 554844.
[23] FLOW Appeals Line 5 Tunnel Permit Decision to Michigan Supreme Court, For Love of Water, https://forloveofwater.org/flow-appeals-line-5-tunnel-michigan-supreme-court/ (last visited April 4, 2025).
[24] See Joseph Regalia, A New Water Law Vista: Rooting the Public Trust Doctrine in the Courts, 108 Ky L. J. 1, 15-16 (2019-2020) (advocating for states to have more robust public trust doctrines if they wish to recognize the public value of fresh water).
[25] For Love of Water, supra note 23
[26] Exec. Order No. 14156, 90 Fed. Reg. 8433 (Jan. 29, 2025).
[27] Order of the Public Service Commission, supra note 7, at 17.