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Watershed association teaches volunteers how to test lake water |
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Thursday, 05 June 2008 |
Ben Copans of the Lake Memphremagog Watershed Association instructs a group of volunteers how to collect water samples to be tested for phosphorus and nitrogen, which contribute to the growth of toxic algae in Lake Memphremagog. (Photo by Laura Carpenter)
By LAURA CARPENTER
Express staff Writer
Ben Copans, the coordinator of the Memphremagog Watershed Association, who is with the Department of Environmental Conservation, along with environmental scientist Fritz Gerhardt, organized a group of volunteers, most of whom are members of the Memphremagog Watershed Association, to test water in small tributaries like brooks that flow into Lake Memphremagog.
The volunteers will fill water containers in specified locations and then send the samples to Waterbury to be tested in a lab.
Phosphorus and nitrogen come from run-off and sediment. Phosphorus is a
problem because it contributes to the growth of plants and algae in the
lake, especially when combined with nitrogen. The concern is on the
growth of cyano bacteria, commonly known as blue-green algae. Not all
blue-green algae is toxic but some is, explained Gerhardt. It looks
like “scum floating on the lake,” and because it’s toxic people cannot
swim in it, and it is known to have killed dogs that have drank it.
A few years ago blue-green algae was present in Lake Memphremagog, but it is not known whether or not it was toxic.
The volunteers will continue to test the water from brooks that flow
into Lake Memphremagog every two weeks until early October. It takes
about one month to get the test results back from the lab in Waterbury.
“It will be mid-winter before we can get the whole picture of what is going on,” Copans said.
Another problem with plant and algae growth is that it could change the
fish that inhabit the lake. Tourism is also a factor to consider
because the lake is a large draw in this area, Copans explained.
Runoff from farm manure or silage pits, or leaky septic tanks
contribute to higher levels of the chemical elements in the brooks.
When the source is discovered the United States Department of
Agriculture helps to correct the problem.
Erosion, water runoff, and stormwater drainage contribute to
phosphorus and nitrogen entering the water. Buffers, such as trees and
vegetation, help to prevent the chemical elements from entering the
water. In some cases fertilizers used on lawns may contain phosphorus
and end up in the water.
The watershed association is working with Memphremagog Conservation
Incorporated (MCI) in Quebec which has been monitoring the lake for
about 40 years. Many residents in Quebec use the lake water for
drinking, so it is of particular concern to them.
The project, which is costly because of lab testing, is funded by a
grant through the Vermont Department of Environmental Conservation
through the LaRosa analytical Laboratory. The purpose of the grants is
to help any volunteer associations and monitoring groups implement new
and ongoing surface water monitoring projects for waters in need of
quality assessment.
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Last Updated ( Monday, 09 June 2008 )
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