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Great Lakes
Article:
Dropping lake levels raise concerns
Of all the Great Lakes, only Ontario's waters have been
high enough not to interfere with boating or shipping.
The year in review.
By Peter Geigen-Miller
London Ontario Free Press
Published December 26, 2005
Water levels on all but one of the Great Lakes are below
long-term average -- and there's concern they could fall
to lows last seen in 2003.
Optimism that levels were rebounding and would be higher
than a year ago by year's end has given way to worry the
opposite may happen.
"I'm a bit concerned that unless we have some wet
weather going into the spring, we could see water levels
similar to 2003," says Chuck Southam, a water resources
engineer with Environment Canada.
That would put levels well below average and create another
summer of hazards for recreational boaters and limit load-carrying
capacity of Great Lakes shipping.
"Right now I'm sitting on a bit of pins and needles
and watching the seasonal decline, hoping it it is not
much bigger than average and hoping we'll see some recovery
in spring," says Southam.
The reason for the drop in levels is a long, hot summer
that reduced the rainfall needed to replenish the lakes.
A stormy November was an exception, the first month run-off
in the Lake Huron basin was above average, says Southam.
A recent bulletin put levels on all but Lake Ontario
below long-term average and all but Ontario below their
levels of a year ago.
Lake levels vary with the seasons, rising with spring
run-off and declining in the fall.
This year levels on Lake Huron peaked about June 24,
a bit earlier than usual, says Southam.
"So far this year, they've gone down about 34 centimetres,
a seasonal decline a bit bigger than normal."
Low water levels are not bad news for everyone.
"Cottagers like lower levels because they have that
much more beach in front of their cottages," says
Geoff Peach of the Lake Huron Centre for Coastal Conservation.
Lower levels also mean less risk of property damage seen
over the past two or three decades when Lake Huron was
higher than average, says Peach. "During that period,
if you were a cottager along the lakeshore, you probably
had quite a few instances when you were wondering if you'd
have a cottage the next summer."
Among those who prefer higher levels are marina operators,
boaters and shippers.
Lower levels increase the risk of boats hitting shoals
and other obstructions. Marina operators may have to dredge
to provide enough water at their docks.
Lower levels also force ships to carry less cargo so
they can negotiate the lakes and connecting channels,
says Peach.
The levels picture is less dire on Lake Erie, which is
a bit below average, says Southam.
"It is most likely to be a bit below average going
into 2006 but it's in a bit better shape than Huron (and)
Michigan."
LAKES
Huron
- 23 cm lower than 2004
- 48 cm below long-term average.
St. Clair
- 10 cm lower than 2004
- 23 cm below long-term average
Erie
- 15 cm lower than 2004
- 10 cm below long-term average
- Same as 2004
- 2.5 cm above long-term average
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