The drought that dried up much of the Midwest during the late 1980s is still keeping water levels on the Great Lakes below their 1986 peak, preventing ships from loading to optimum capacity.
Glen Nekvasil, communications director for the Cleveland-based Lake Carriers' Association, said Wednesday the lake levels have regained most of the 17 inches of depth they lost to heat from 1986 to 1988, but vessels are still being light loaded.Mr. Nekvasil said the association had to fight during the 1980s to head off a push to divert some lake waters to other, thirstier parts of the country. The group keeps mentioning the water level problem so that "if the threat comes up again, people will know our position."
Even without that diversion threat, water levels and some related problems are getting in the way of full vessel loadings. "In this super-competitive age, it certainly isn't helping any," he said.
Association members operate U.S.-flag ships that haul bulk cargoes between U.S. and Canadian ports within the lakes, and rarely exit the St. Lawrence Seaway. The members' fleets include 13 of those big ships and each vessel averages 40 trips or more each year.
Last year they carried 104 million net tons of cargoes such as iron ore, limestone, coal, salt and sand, down from 112 million tons in 1990. So far in 1992, combined loadings of iron ore, coal and stone are down 1 percent from the 1991 period.
The members' ship loads, Mr. Nekvasil said, are limited by the depth of the Soo Lock, which is deeper than ocean ships encounter through the St. Lawrence lock system.
At the Soo so far this year it's probably an average of about 27 feet, four inches for vessel loadings, but that should improve slightly by mid- summer, Mr. Nekvasil said. That compares with loadings of 28 feet, one inch back in 1986.
While that nine-inch shortfall may not sound like much, the group's recently released annual report for 1991 said the largest lake freighters lose up to 267 tons of cargo capacity each for every one-inch draft reduction.
Even if the average loss is just six inches by midyear, Mr. Nekvasil said, the half a foot for a 1,000-footer is about 1,600 tons of cargo each trip.
The loadings issue is aggravated, the association said, by ongoing limits on dredging in some ports - Indiana Harbor near Chicago, and Toledo - because of lack of available dredge disposal sites, and by pleasure boating that clogs up Cleveland's Cuyahoga River for freight traffic.