Lake Champlain Ecosystem Assessment

Negative Externalities of Hydroelectric power

If hydroelectric potential were utilized, there would be several environmental quality implications to the Lake Champlain Basin.

A study of several dams in the Connecticut River watersheds have shown that the construction of dams creates the ideal habitat for a mercury-producing bacteria that flourishes in shoreline soils that alternate between being dry and water covered – the sort of habitat a damn creates when it opens and closes its flood gates to harness power. This mercury can be absorbed by fish, raising their overall mercury levels and creating a health risk to people and birds that eat the fish (Fountain, 2007). Several species in Lake Champlain have already been cited as a health risk due to their high mercury levels (Meyers, 1999).

Another problem that would have to be confronted with hydroelectric dams is the damage that would result from Zebra mussels. This invasive specie is prevalent in the Lake, and studies throughout North America have found that where zebra mussels are present, they can have very expensive impacts on aquatic infrasructure. Two institutions, a university campus on Lake Michigan and a residential care facility on Lake Champlain, reported total zebra mussel-related expenses of $27,000; $2,000 for monitoring and $25,000 for prevention. A study of 56 locks spent an average of $3,416 each on Rivers and the Great Lakes (O’Neil, 1997). If hydroelectric potential were planned for Lake Champlain, these costs would have to be considered as a part of long-term maintenance.

A common concern with dams is the mobility of fish. One study on a New York stream that dates back to 1987 shows that  fish bypasses a high rate of effectiveness at mitigating the interruption of fish movement (Nettles and Gloss, 1987). There are several different types of fish bypasses, each with different costs and effectiveness, so the appropriately chosen type could prove to limit the habitat harm to fish in the Lake Champlain tributary rivers.

A final significant impact to consider with hydroelectric dams would be pollution. In dams that flood land, the underwater decomposing organic material can cause the release of methane, carbon dioxide, and hydrogen sulfide. The biological oxidation of methane results in rapid oxygen consumption in lake and river waters, which can lower fish populations. About 10% of the carbon stored in the submerged soil and vegetation gets released in gaseous form within 2 years of submersion (Galy-Lacaux, 1997).

Fountain, Kristen. (2007). Study links mercury to local dams, plants. Valley News, White River Junction, Retrieved from www.briloon.org/pub/media/ValleyNews1.10.07.pdf

Galy-Lacaux, C. (1997). Gaseous emissions and oxygen consumption in hydroelectric dams. Global Biogeochemical Cycles, Retrieved from http://www.agu.org/pubs/crossref/1997/97GB01625.shtml

Meyers, Jeff. (1999). Mercury pollution in the lake champlain basin. Retrieved from http://www.harborwatch.com/news/mercury_pollutionin_the_lake_cha.htm

Nettles, DC, & Gloss, SP. (1987). Migration of landlocked atlantic salmon and effectiveness of a fish bypass structure at a small scale hydroelectric facility. American Fisheries Society, 7(4), Retrieved from http://afsjournals.org/doi/abs/10.1577/1548-8659%281987%297%3C562%3AMOLASS%3E2.0.CO%3B2

O’Neil, Charles. (1997). Economic impact of zebra mussels – results of the 1995 national zebra mussel information clearinghouse study. Great Lakes Research Review, 3(1), Retrieved from http://74.125.155.132/scholar?q=cache:BhizOVhKJ-EJ:scholar.google.com/+lake+champlain+dam&hl=en&as_sdt=40000000000000