Thursday, November 1, 2007

Down the drain

Anyone who spent time on the Great Lakes this summer probably knows that it's been a bad year for water levels.

How bad? The upper lakes are the worst affected, with Lake Superior setting an average low in September that hasn't been seen since the U.S. government started keeping track over 147 years ago (the effects are clearly visible in these photos, taken near Duluth, Minnesota). The good news is that Superior is up slightly, though still down overall, because of record rainfall over the past few weeks.

In turn, the tourism business has been suffering, and freighters have been loaded lighter and lighter to deal with the dropping levels, meaning millions of dollars in lost revenue. On Georgian Bay, cottagers have been building ever-longer docks over the expanding mucky weed beds that mark the spots where they used to tie up their boats.

So what's the culprit? Some say the lakes are showing early signs of stress due to climate change. Others point to dredging of the St. Clair River in the 1960s by the U.S. Army Corps of Engineers that was intended to, ironically, allow larger ships to pass between Lakes Erie and Huron. The dredging, they claim, has led to erosion of the riverbed, creating an ever-expanding and faster-flowing St. Clair, which essentially drains the upper lakes of water. One study pegs the water loss through the St. Clair "drain plug" at over 9 BILLION litres per day.

Answers are scarce. But they'll have to be found soon if we're to preserve this crucial water resource for future generations.

To read more about the Great Lakes' water-level woes, click on the links below.

Detroit Free Press
Soo Today
Kingston Whig Standard

Photos courtesy University of Wisconsin Sea Grant Program.

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