Page 8 - SLPOA Spring 2014 Newsletter

SPRING 2014 NEWSLETTER SHARBOT LAKE PROPERTY OWNERS’ ASSOCIATION

THE RISE AND FALL… cont’d

WHY DOES THIS OCCUR? Inattention, such as
a more lax attitude towards shoreline development
and the use of cleaning fluids in our homes, is added
to with more diffuse sources of pollution. There are
large quantities of phosphorus in runoff from our
villages and from farmland. Some of this increase is
due to changes on the ground. This includes more
construction – such as the new school – and more
intensive agriculture using bio-available fertilizers.
Such changes leave more phosphorus on the ground
to be dissolved in the runoff (surface and sub-
surface). Loss of wetlands, as evidenced by new
construction along Highway 38, allows more rapid
discharge to the lake as well.
But the contribution of the changing climate has
also been critical. Studies of the Great Lakes
watershed area have shown that the annual number We must therefore renew our commitment to
of surface runoff events has increased 18% from the preventive actions. Steps must be taken to reduce
1970s due to more frequent heavy rains and winter phosphorus sources, on farmland and in village areas,
snowmelt periods. Intense precipitation events from ending up in the lakes. Lakefront property
increase in a warming climate, in theory by 7% per owners are on the front line. They must become the
degree C temperature increase. One of the champions of how to do things better.
consequences of this combination of changing land In the Great Lakes, by the way, a new era of toxic
use and changing climate is that larger quantities of chemical pollution has also been documented. For
the nutrient phosphorus are carried in the runoff. highly toxic mercury, after reductions from 1970 to
This is a double whammy: increased large flow
events on the one hand, and higher concentrations of 2005, scientists now see concentrations on the rise
again in some fish and fish-eating birds such as loons,
dissolved reactive phosphorus in those flows on the since 2005. Coal-fired electricity generation plants in
other. When these polluted flows reach the USA continue to be a major airborne source of
warming waters of our lakes, larger algal blooms are mercury to the Great Lakes, although Ontario has
produced. In the most recent report on our lake by
the MVCA we learned that re-eutrophication is thankfully reduced its coal-burning power plants.
beginning to be observed in Sharbot Lake. The good news is that serious health and ecosystem
threats from DDT and from PCBs, have decreased, as
a result of regulations, as shown by analysis of herring
gull eggs at Burlington since 1972. Sharbot Lake and
all lakes in southern and south eastern Ontario benefit
from improvements such as these.
The new contaminants finding their way to the Great
Lakes include drugs and pharmaceuticals dumped or
excreted. For example there are small, but growing,
concentrations of anti-inflammatory drugs in Lake
Erie’s open water, far from shore. Anti-depressants
are observed in Lake Ontario and antibiotics down the
St. Lawrence River. Endocrine disrupting substances
are found in Lake Huron. The gender composition of

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