Great Lakes shipping season begins -- a look at the history

The Great Lakes shipping season is officially back.

The Poe Lock at the Soo Locks in Sault Ste. Marie reopened just after midnight. The first ship to make the crossing this year was the Michigan Trader, an 850-foot ship on its way to Wisconsin to pick up iron ore pellets.

What exactly is a lock?

Think of it this way: It’s a device that raises or lowers boats and ships between two stretches of water that sit at different levels—kind of like a step in a staircase—but for rivers and canals.

Here’s how it works: A ship pulls into the lock, gates close, then the lock either fills with water to lift the vessel higher or drains to lower it.

The easiest way to picture it is that it’s a water elevator for massive ships carrying thousands of tons of cargo.

For a full look into the history of the Great Lakes shipping seasons, you can watch the video at the beginning of this article.