Posted Draft EIS Comments

I urge the U.S. Army Corps of Engineers, Detroit District, to reject a rushed approval of the Line 5 tunnel project. This project has not undergone a comprehensive risk assessment to determine the full scope of the impact on the climate, Indigenous rights, and public health. Concerns have already been raised by tunnel experts and state consultants about the logistics of creating a tunnel under the lakebed, especially given the porous quality of the rock. There could be risk of explosion (if natural gas leaks into air pockets within the tunnel or the rocks) or risk of oil or gas leaks into the Great Lakes. A failure of this project would be catastrophic for the communities that rely on the Great Lakes for clean drinking water and more than a million jobs that are tied to the Great Lakes. For that reason, there needs to be the highest level of review and scrutiny for any risks associated with this project, and the current research does not go far enough to address and alleviate these concerns.
Approving this tunnel will continue to lock us in to fossil fuel dependency for decades, at a time when it is critical to cut fossil fuel usage to combat the worst effects of climate change. PLG Consulting did a study during the Bad River Band case in Wisconsin that determined that almost every barrel of oil that is currently supplied by Line 5 could be replaced by other sources within 3 months. Based on that, the proposed tunnel project would not be needed, and the current Line 5 pipeline could be decommissioned. As a replacement, Enbridge could continue their investments in renewable energy (currently, large-scale renewable energy investments are cheaper than fossil fuels for energy use).
Overall, this project is risky for the Great Lakes, Michigan, and the climate, and there has not been a sufficient comprehensive risk assessment completed to identify and address all the concerns. I urge the U.S. Army Corps of Engineers, Detroit District, to reject this project based on the lack of investigation into all potential risks, especially regarding the impact to climate change.

My name is Dr. Steven Ashmead MD, a Family physician in Michigan I am writing on behalf of myself but also as a Board Member of Michigan Clinicians for Climate Action, an organization of health care providers and others concerned about health of the people of Michigan. I recommend AGAINST approval of the pipeline.

The most important reasons NOT to build this tunnel are because of its health concerns, including the air pollution caused by the burning of petroleum, including that carried by this tunnel, in our vehicles, businesses, and homes, and the health harms associated with climate change caused by the fossil fuels carried by this tunnel. Additionally the health risks of the inevitable oil spills that will occur from this pipeline must be considered. The risks of pollution of the largest fresh water lakes in the world cannot be minimized .

Regarding air pollution, few people are aware of the huge effects of air pollution on everyone’s health. The worst components of the air pollution are the particulate matter 2.5 microns and smaller . The harms continue even when we can’t see the pollution and when the air pollution is within the limits as defined by the EPA. The leading problems caused by this pollution are heart disease and stroke, followed by chronic lung disease, lung infections, and lung cancer. It also contributes to problems in our children including low birth weight, asthma, autism, and others. These problems cause about 100,000 deaths in the US and 8 million worldwide each year.

Regarding the effects of climate change, there is no doubt that the fossil fuels, including those carried by this tunnel, are leading to warming of our planet. Direct heat effects can be a large problem, especially for agricultural and industrial workers, but also for young children and the elderly. Climate change makes conditions more favorable for infections including Lyme disease, which is increasing substantially in Michigan and other states. It contributes to deaths and other health problems from extreme health events, such as Hurricane Helene which hit North Carolina and other states last fall, causing many deaths and $60B in damages . The wildfire in California in 2025 causing billions of dollars in damages are attributable in part to climate change caused by continual burning of fossil fuels.


This tunnel is intended to continue our dependence on petroleum and other fossil fuels from the 19th and 20th century. A better idea that we as a society should be moving to the clean energy sources of the 21st century.

If this application is to move forward, I recommend that health analysis be performed that assesses the harms to health caused by the dirty petroleum that will flow through this tunnel. Additionally the health risks of the inevitable oil spills that will occur from this pipeline must be considered .

Please find the attached letter that details our energetic support of this well-conceived project.

I support shutting down line 5 work and removing the pipeline from the bottom of the straights as soon as safely possible. It is inconceivable to me that such a project is allowed in such a sensitive area. The water quality of the Great Lakes is far more important than whatever benefits the pipeline may offer for the transport of this oil.

The Line 5 pipeline should just be shut down with no replacement tunnels. Enbridge and the Army Corps overstate the economic importance of the pipeline. Court documents show an Enbridge consultant said a Line 5 shutdown would raise gas prices by a half-cent per gallon. The environmental risks are just not worth it, and climate change demands that we keep pressing to reduce our use of fossil fuels. This is an opportunity to do just that by shutting down the Line 5 pipeline.

As a past oil regulatory geologist with the Michigan Geological Survey who also owned a geological consulting firm specializing in mapping and boring Niagaran Age limestone and dolomite such as the Mackinac Breccia Formation and associated collapsed Pointe Aux Chenes Formation, please heed the following grave concerns with allowing the “tunnel” to transport hydrocarbons under the Straits of Mackinac. By their very nature, “brecciated” rock formations are in fact fractured, broken and deformed by geological processes, including faulting, volcanic activity, and sedimentary compaction. It’s reckless to assume that the re-calcification of the fabric the brecciathat formation and resulting collapse of the Pointe Aux Chenes has “geologic integrity”. Some of the worst groundwater and surface water contamination in recent decades have resulted in blind assumptions on the integrity of rock formations known to be fractured and karst. And that is the case with this project.

The public trust demands that you protect the most valuable natural resource of the Great Lakes and their ecosystems by denying building of the tunnel plus removal of the outdated and hazardous line laying on the bottom of Lake Michigan. If you’re unsure, simply go through several “risk-reward” ratios and hopefully you’ll see that rewarding the monetary pocket of Canadian corporations in the relative short term cannot begin to outweigh the long term risk of damaging the surface, ground water, and Great Lakes ecosystems of “Pure Michigan’

I fully support the Line 5 Tunnel Project underneath the bedrock of The Straits of Mackinaw! This project is a win-win situation and a no-brainer. Dig Baby Dig!

MEG Letter of Comment on USACE DEIS for GLTP6.13.25