(CBS News) CHICAGO - The government reported this week the ongoing drought is getting worse. More than half the country - and virtually all of Texas - is experiencing drought.
The 2013 shipping season opened this week on the Great Lakes, with enormous freighters passing through the locks at Sioux St. Marie, Mich.
This year, however, the industry is awash in uncertainty.
The persistent drought has produced some of the lowest levels ever recorded in Lake Michigan and Lake Huron. And as a consequence, the big ships that carry iron ore to mills around the lakes are now being forced to lighten their loads - or risk running aground.
"When she came down with her cargo here - the last cargo in January - she was at the 25 mark. If she had been loaded to her full mark, she would have been up just an inch short of 28 feet," said , vice president at the Lake Carriers Association - a trade group that represents shippers.
Last month CBS News went aboard the Stewart J. Cort in the Port of Milwaukee. As long as an aircraft carrier, the ship can carry 65,000 tons of ore.
"When this ship loaded its last cargo of the season, it had only 55,000 tons on board," Nekvasil said.
If a ship is 10,000 tons of ore short, "that means a steel mill didn't make about 6,700 tons of steel and that could have been turned into 8,400 cars. And 8,400 cars would keep a large auto plant working for 15 days," he explained. "And you have to remember that's on just one trip. These ships will make 45 to 50 trips during a season."
Precipitation in February and March over the Michigan and Huron basin has been close to average, and the levels are now about two inches higher than they were in January, when the record lows were reached.
But that's still about 26 inches - more than two feet - lower than where the lakes usually are.
And the mild winter temperatures didn't help. There was little ice cover over the water this year, allowing evaporation to drain even more moisture from the lakes.
So while Friday was nice and sunny and made the lakes just glisten, there are a lot of people who would prefer a slate-gray overcast and plenty more rain.