The biggest of the five Great Lakes is getting smaller. The water level in Lake Superior is lower than most people can remember, just above record low levels set 80 years ago.
Experts blame several years of below-normal precipitation for the drop. While low water is an inconvenience for people trying to launch their recreational boats in shallow harbors, it's an expensive problem for the companies that fill thousand-foot long ships with coal and iron ore.
Lake Superior is the uppermost of the five Great Lakes, stretching 350 miles from Duluth to the eastern tip of Upper Michigan. But its down some 18 inches from the base level considered normal. It's a foot lower than it was just a year ago. A month ago, the lake's surface almost broke the record low set in 1926.
That kind of a drop doesn't show much in the lake's deep interior, but it's obvious near the shorelines and in the harbors.
A recent sunny afternoon in Duluth, Minn., was perfect weather to launch recreational boats at the Harbor Cove Marina. But some of the powerboats were getting their propellers stuck in the mud. Marina manager Zach Crosby says some of the sailboats won't get off land this summer.
"I have probably six sail boats that won't be able to go in at all, because it's just too shallow," Crosby said. "I have several folks who are anxiously awaiting rain."
Duluth's Minnesota Point is essentially a barrier island that forms Lake Superior's far western end. In places, the harbor side of the point is just drying up. Long brown fingers of mud are showing up, sprinkled with timbers and tires and the odd junk that's accumulated over years, unseen and underwater, until now.
Across the harbor is the Midwest Energy Resources terminal in Superior, Wis., where Montana coal is loaded into ships for transport to the east. Fred Shusterich manages the facility. From the terminal dock dozens of feet above the cold water, Shusterich points out things he's never seen before.
"Well, right over south of our dock here, there's an island between the dock and our shoreline. I've never seen that," Shusterich said. "There's a lot of pilings sticking out from old docks, abandoned docks."
At the terminal, a stream of shiny dark coal floods into the gaping holds of a thousand-foot long lake freighter. It's a low, flat ship a third larger than the ill-fated Edmund Fitzgerald.
Shusterich says the huge ships are loading less coal than they used to. They're loading light to avoid hitting bottom — especially on the sharp rocks in the St. Mary's River, which connects Lake Superior to Lake Huron. The big ships are leaving a lot of coal behind. Every inch of water counts.
"On a thousand-footer ... one inch of draft is about 250 to 267 tons, depending on vessel hull configurations," Shusterich said.
It's the same story at the port's ore docks that load iron ore for steel mills in places like Cleveland and Chicago. Port Director Adolf Ojard says it takes more ships to do the same job.
"Just last year, we required 42 more ships to load at our port to handle the comparable or same amount of tonnage," Ojard said. "Last year every ship loaded on average 681 tons lighter than it did the previous year."
And that, he says, drives up the cost of shipping, plus the cost of coal-fired electricity, and even steel.
There are signs, though, that a long drought might be easing. April was a little wetter than normal, but it's too early to declare the drought over. Even with typical precipitation, it could take years to restore the level on a lake as vast as Superior.
Bob Kelleher of Minnesota Public Radio reports.