Shipping is in full swing, and people love watching the lakers and salties move through our ports.

You may have noticed some numbers and markings on the bottom of the boats.

The numbers measure how deep the vessel is sitting. So if the water is hitting at the 29 mark, it’s 29 feet to the bottom of the hull.

Vessel agents like Steve Sydow from Daniel’s Shipping Services help their clients decide how much cargo to load, so the saltie can transit safely from half a world away.

For example, his next vessel is one carrying cement from Turkey.

“We have to load very carefully, down to the one centimeter mark,” he said. He has to calculate for fuel as well, and the water levels through the entire seaway.

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There is a maximum load each vessel can take, based on the design of the ship, the type of water, the season, and weather conditions.

This year’s mild winter is not helpful for heavier loads, which are better for the bottom line.

“The lack of snow and ice meant a lot of water from the lake evaporated. And our long term forecast for water levels does not look good,” Sydow added.

There is a small silver lining for those navigating night and day. “The lack of ice made things easier getting in and out of the port,” shared Captain Dan Rentschler.

He is a pilot with the Western Great Lakes Pilots Association. Federal law mandates a pilot be on board foreign vessels when they enter the Great Lakes. They can be American or Canadian.

“The main job of the pilot is to protect the environment and to protect the infrastructure from the ship,” he explained.

Before he became a pilot, he was a captain on the ore boats for U.S. Steel. He’s been on all kinds of vessels, like the USS Minneapolis-Saint Paul, when it came to Duluth for her commissioning.

He lays out the course, and gets them tied up. “When we’re close to Duluth, I’ll actively take over the ship and bring it into port and bring it to the dock,” Rentschler said.

Pilots are watching the water levels too, because they never want the ship to run aground, which is when it gets stuck on the bottom.

It might mean a last minute change or two. “Sometimes we have to chart a new path, or wait for the water levels to come back. Sometimes the wind will drive the water back in. Usually we load to the worst-case scenario,” he said.

According to the U.S. Army Corp of Engineers, Lake Superior is down two inches below normal for this time of year. And compared to last year, it’s down 13 inches.

Now, even if the water levels were normal, the Lake Carriers Association said their members have to load less. But high water levels means the lakers have to slow down, so their wake doesn’t cause damage or flooding.

The Duluth Seaway Port Authority shared more. Jayson Hron is the Director of Marketing and Communication. “We began the season on the Great Lakes/St. Lawrence Seaway with some speed restrictions due to low water levels. Recently those eased a bit, and we’re trending in the right direction,” he said.

Timing wise, the waters are on the way up. “We are entering the seasonal cycle of lake waters rising. The U.S. Army Corp is predicting a fairly significant rise in the next couple of months,” Hron said.

Overall though, the data shows water levels are trending downward. So the industry may have to consider a new normal.

Especially in places like the Mississippi River or the Panama Canal, which may have restrictions with how many vessels can go through.

Delays can end up costing the consumer more, down the line.

Even if you can’t see the cargo, it is important to our every day lives. Grain turns into pasta. Iron ore turns into steel and into vehicles.

Moving those cargoes takes thousands of people working the waterfront.

People like Captain Dan. “I love interacting with crews from all over the world. It’s always entertaining to share in their cultures, their food, and their general outlooks on life in general. I hear great stories,” he shared.

Stories while sailing. And watching for the next arrival.

“I tell people my job is like riding a motorcycle while you’re playing chess, with the chessboard on the tank of the motor. You have to ride and play chess and watch and move pieces and think. But I do enjoy it,” Sydow added.

Monday marked the 70th anniversary of the creation of the Great Lakes St. Lawrence Seaway, when the Wiley-Dondero Act was signed.

For more about lake levels from the Army Corp: https://www.lre.usace.army.mil/Missions/Great-Lakes-Information/Great-Lakes-Water-Levels/Water-Level-Forecast/Weekly-Great-Lakes-Water-Levels/