Great Lakes' Lower Water Levels Propel a Cascade of Hardships

Decreased ice cover on the Great Lakes, probably caused by increasing air and water temperatures and high winds, is a major culprit in lowering water levels, which have hurt the shipping industry, forced lakeside power plants to extend their cooling pipes, frustrated recreational boaters, dried up wetlands and left coastal landowners with docks extending over yards of unsightly muck.

In September, Lake Superior broke its 81-year-old low-water record by 1.6 inches, and last month it was a foot below its seasonal average. It appeared that Lake Michigan and Lake Huron would log record lows for January until storms helped levels stay above the marks set in the 1960s.

"And we're not talking inches, we're talking feet," Nekvasil said. "It's not just affecting the steamships; it's the steelworkers who depend on that iron ore, the workers at the limestone quarries. We move the raw materials that keep everyone else going."

"We firmly believe the changes we're seeing are impacting fisheries, possibly in a dramatic way," said Jeff Skelding of the National Wildlife Federation. "Disruption of habitat will impede fish species from being able to reproduce."

More than 99 percent of the Great Lakes' water is left over from melting glaciers, and less than 1 percent is replenished each year through groundwater, rainfall and snowmelt. Water lost through increased evaporation or diversion may be gone forever.

Read more By Kari Lydersen, Washington Post