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Friday, May 2, 2008

How low will lake levels go?

Crews from The King Company of Holland work on dredging at the end of the Muskegon channel last Monday. Enlarge photo.
West Michigan residents concerned about sinking Great Lakes water levels will get a chance to share their views this week when U.S. and Canadian officials studying the issue visit Muskegon.

The International Joint Commission, a U.S.-Canadian panel that advises the two nations on Great Lakes issues, is studying water levels in lakes Michigan, Huron, Superior and Erie. A committee working on the IJC's International Upper Great Lakes Study will host a public hearing on lake levels Sunday, from 10 a.m. to noon, at Grand Valley State University's Annis Water Resources Institute, 740 W. Shoreline.


"We want to hear lots of people come out and squawk at this public meeting," said John Nevin, an IJC spokesman. "We want to hear what this issue means to people when the water is really high or really low."

IJC officials might get an earful.

Lake Michigan's water level has dropped nearly four feet since 1997, according to federal data. The low lake level has widened beaches but created safety hazards for recreational boaters and caused freighters to run aground in Muskegon, Grand Haven and other ports around the lake.

On the flip side, record-high lake levels in 1986 caused severe beach erosion that sent several Grand Haven cottages tumbling into the lake.

People standing on Muskegon's south pierhead watch the Indiana Harbor freighter after it ran aground last August. The freighter was headed for Consumer Energy's B.C. Cobb plant. Enlarge photo.

The IJC study is focused on two issues: Whether dredging in the St. Clair River over the past century has caused excessive lowering of water levels in lakes Michigan and Huron; and if the volume of water flowing out of Lake Superior daily through control structures in the St. Marys River should be adjusted to account for below-average precipitation and global warming, which some studies suggest could lower lake levels by several feet over the next century.

The study could prompt changes, such as the construction of a water control structure in the St. Clair River, that would affect water levels in lakes Michigan and Huron, said Gene Stakhiv, co-chair of the International Upper Lakes Study Board.

"There are a whole range of changes in the regulation of flow and physical structures in the (Great Lakes) system that could help us control water levels," Stakhiv said. "But we don't know yet if there is a need for that."

A growing chorus of critics -- from scientists and shoreline property owners in Lake Huron's Georgian Bay, to marina owners and shipping interests -- want the U.S. and Canadian governments to plug what amounts to an unnaturally large drain hole in the St. Clair River.

Studies have shown that dredging in the St. Clair River between 1900 and 1962 caused water levels in lakes Michigan and Huron to drop by at least 15 inches. The lower water levels have forced freighters to lighten loads, caused some ships to run aground, made recreational boating dangerous and left some islands in Georgian Bay high and dry.

Nearly all the water in lakes Michigan and Huron, which are technically one lake, drains into the St. Clair River, which flows into the Detroit River and Lake Erie. Michigan and Huron are the only Great Lakes without manmade structures to control water flow and lake levels.

Lake Michigan's water level has dropped nearly four feet over the past decade and Lake Superior dipped to a record low last year. The plunging water levels have some Great Lakes scientists and residents wondering whether factors other than weather conditions are causing lake levels to drop.

This year's hard winter, which delivered above average precipitation to the region, has slightly elevated lake levels, but the water level in Lake Michigan-Huron remains 21 inches below its long term average. Lake Superior's level is 11 inches below average but Lake Erie, the recipient of water from lakes Superior, Michigan and Huron, is eight inches above average, according to government data.

The American Integrity freighter is pictured near Muskegon's south pierhead after it ran aground last September just outside of the channel breakwall. The freighter was headed for Consumer Energy's B.C. Cobb plant. Enlarge photo.

A recent study commissioned by the Ontario-based Georgian Bay Association claimed a 1962 dredging project in the St. Clair River caused the river bottom to erode to twice its natural depth, effectively creating a larger drain hole for lakes Michigan and Huron.

The deeper channel is siphoning off 2.5 billion gallons of water daily out of the two lakes, according to the group's study. That water flows through Lake Erie, Lake Ontario and the St. Lawrence River en route to the Atlantic Ocean.

Roger Gauthier, a hydrologist with the Great Lakes Commission, said the U.S. Army Corps of Engineers could fix the excessive loss of water down the St. Clair River within a year by installing flow control structures near Port Huron.

"They could control erosion in the St. Clair River with underwater speed bumps -- inflatable bladders that could hold back water (in Lake Huron) when water levels are low," Gauthier said.

When the Corps of Engineers deepened the St. Clair River channel in 1962, the agency drafted blueprints for a concrete weir on the river bottom to control water levels in lakes Huron and Michigan. But the weir was never built because lake levels were generally above average from 1964 through about 1997; water levels have dropped like a stone since 1997.

Kay Felt, the U.S. co-chair of an advisory group working on the Upper Great Lakes Study, said it makes no sense to consider possible remedies before the $14.5 million study is completed.

"There are a lot of people who want a quick and dirty fix," Felt said. "It may sound like a good idea to go right to a solution but that's not an appropriate thing to do at this point -- people don't want a truncated solution, they want a solution based on science."

The St. Clair River portion of the study is scheduled to be finished in June 2009; the Lake Superior study will be completed in 2011.

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