Erie: Is clearer cleaner?
By John Bartlett
From Sam Leo's perspective, Lake Erie has never looked
"It's certainly so much better now than when I started
up here," said Leo, of J & S Dive Shop, who has
been diving in Lake Erie for more than 40 years. "Back
then it was dark and dirty."
But he admits appearances can be deceiving, which is
why he was not so much surprised as interested in the
growing concerns many scientists are now expressing about
Those concerns were at the forefront of a Lake Erie workshop
at the recent International Joint Commission's Great Lakes
Conference and Biennial Meeting in Ann Arbor, Mich.
The workshop was titled: "Lake Erie: Déjà
Herb Gray, chairman of the IJC's Canadian session, bluntly
told the attendees that based on the briefings, conditions
of Lake Erie are backsliding.
Prompting that dismal assessment are several phenomena
that have emerged in recent years. High among them:
n The extensive outbreaks of Type E botulism in Lake
Erie beginning in 1999 and continuing every year through
2002, killing thousands of birds and untold numbers of
fish, mudpuppies and other aquatic life. Researchers are
holding their breath this year, hoping the worst is over
with no widespread cases reported so far.
n The enormous "dead zone," an area where oxygen
is so depleted that most fish and other aquatic life cannot
survive. The dead zone emerged in Lake Erie's central
basin in 2001 and 2002.
Oxygen-deprived zones are a regular summertime occurrence
in the lake's central basin, where the water separates
into two layers with the warmer top layer trapping the
colder waters beneath it. The bottom layer is cut off
from an oxygen source, and plants, animals and decaying
material use up the oxygen in the lower level.
The difference is in the size. Large dead zones were
a feature of the lake in the 1960s and early 1970s when
heavy loadings of phosphorous and other polluting nutrients
created a cycle of plants and decaying material that used
up oxygen supplies.
Researchers continue to evaluate this summer's dead zones
and whether they again were excessively large and indicative
of some larger environmental problem.
n The resurgence of a toxic form of blue-green algae
in the western basin in recent summers. It was particularly
plentiful this summer and especially in the area of Maumee
Like the dead zone, the algae was prevalent in the polluted
1960s and 1970s when phosphorous and other nutrients fed
n The continued loading of the lake with mercury, a toxic
metal. Lake Erie has the highest mercury concentration
of any of the Great Lakes, much of it carried to the lake
on the wind from power plants and other industries.
n The prevalence of invasive species, such as zebra mussels,
that have disrupted the ecosystem, and might well be driving
some of the less-than-encouraging changes in the lake.
"When I look at it, it seems like we are still seeing
improvements, but we're not scientists and they see much
more," Leo said. "There are a lot of things
The scientists share that sentiment.
"There are a lot of changes that we don't understand,"
said John Gannon, a senior research scientist with the
International Joint Commission. "Some indicate some
backsliding, but at the same time, there are some positive
Among the most positive has been the phenomenal return
of Lake Erie's mayflies, which indicate greatly improved
water and sediment quality, he said.
"I think the jury is still out on a lot of this,"
said Lori Boughton, chief of the state Department of Environmental
Protection's Office of the Great Lakes. "People are
raising concerns, but I've not heard the lake is dying
Pollution was so prevalent, nutrient loading so high
and water quality so poor in the 1960s and early 1970s
that many declared Lake Erie dead.
Finding the sources - the cause and effect - of today's
emerging problems might prove much more difficult, Gannon
"I don't think we have the luxury any more of looking
at the factors in isolation - the nutrient loading, toxic
contaminants and invasive species," he said. "I
think these things are co-occurring and require a much
more intense and coordinated research effort to make the
linkages and understand what's going on."
Leo, who will only admit to being a senior citizen, said
he's always pleased to tell people how clean Lake Erie
has become since he first dove into its waters.
"The government has done a good job with pollution
control," he said. "I hope they can figure this
new stuff out."