Could an Auto Tunnel Replace the Mackinac Bridge Between Michigan’s Peninsulas?

The Mackinac Bridge is almost certainly the best known symbol for the state of Michigan. The bridge effortlessly moves traffic across the State of Michigan between the Lower and Upper Peninsulas, a replacement for an inefficient ferry system that once caused hours of traffic backups.

There are those who get a little fearful of crossing the bridge and rare time during inclement weather when the bridge actually closes stranding cars in the opposite peninsula from where they need to be.

So is there another solution for crossing the straits of Mackinac? What would it look like to go under them in a tunnel?

This comment came up in a discussion on social media about what drivers should do when the bridge closes in bad weather:

if they can build a tunnel for the pipe line the could build one for vehicles.

It's a really interesting thought. The Straits are roughly 5 miles across at that point (a fact that surprises out-of-state drivers who approach the Mackinac Bridge for the first time). The "pipe line" tunnel refers to the Great Lakes Tunnel Project, a proposed natural gas and oil pipeline, popularly known by supporters and detractors as 'Line 5.'

More Mackinac Bridge Lore

• There Are Michigan Natives Who Really Don't Care About Ever Seeing the Mackinac Bridge
• Urban Legend: Is Michigan's Mackinac Bridge A Mile Above the Water?
• Visitors to Michigan Are Often Surprised to Learn You Can Drive Under the Mackinac Bridge

A tunnel under the Mackinac Bridge would be the longest in the Untied States, that title at 2.5 miles is currently held by the Anton Anderson Memorial Tunnel in Whittier, Alaska.

Mackinac Straits Tunnel Feasibility

But at 5 miles or so under the Straits, it would be no where near the longest tunnels in the world. The well known Channel Tunnel or Chunnel, the railway between England and France is 31 miles. For road tunnels, Norway leads the way in the world with a 24 mile long passage.

👇🏼BELOW: 24 Bridges to Enter the Upper Peninsula of Michigan that Aren't the Mackinac Bridge + Mackinac Bridge Mishaps👇🏼

Technically can a tunnel under the Straits of Mackinac be done? Most assuredly, we have the tech to do it. Is there the need, the funds and the desire to construct it? Almost certainly not.