The Mackinac Bridge Should Not be Part of America’s Interstate Highway System – Here’s Why

You would be hard pressed to find a more iconic piece of the highway system in Michigan than the Mackinac Bridge. The engineering marvel is a 5 mile suspension bridge that majestically connects Michigan's Upper and Lower Peninsulas.

It's an instantly recognizable symbol of the state and carries Interstate 75 on its cross-country journey from the Canadian border at Sault Ste. Marie to Miami.

However, by the strictest rules, the Mackinac Bridge should not be part of I-75 The reason? The bridge was not built to the standards of the interstate highway system.

READ MORE: Michigan Once Considered a Plan That Would Have Built a Bridge to Mackinac Island

Highways have standards they must meet to earn that coveted red-white-and-blue shield and be called an interstate. With the Mighty Mac being built before the inception of the interstate highways, the bridge does not meet those standards and was given an exception to the rules based on its vital importance.

Interstate Standards and the Mackinac Bridge

There are certain things highways must have on the interstate system in terms of shoulders and medians between travel lanes in different directions.

The biggest offending feature of the bridge - the non-existent median. When crossing the bridge there is a narrow hump of just a few feet between left-lane drivers. That's a no-no in interstate highway construction.

While it's not likely the bridge could ever conform to modern interstate standards, neither will it ever lose its Interstate 75 designation. So your non-conformity is safe with us, Mac.