Policy Documents

The Great Acid Rain Flimflam

Edward C. Krug –
January 1, 1992

For more than a dozen years, the conventional wisdom among scientists, environmentalists,
and politicians has blamed acid rain for the depletion of game fisheries in the Adirondacks and
Nova Scotia and for substantial damage to forests from Vermont to North Carolina. The
government of Canada certainly takes this view, and regards acid rainclouds from the Midwest
as one of its principal sources of tension with the United States. President Carter endorsed a
report by his Council on Environmental Quality calling acid rain one of the two most serious
environmental problems of the century. It is largely to reduce the acid in rain that President
Bush’s Clean Air legislation calls for a 50 percent reduction in sulfur dioxide emissions (10 million
tons) by the year 2000, at an estimated cost of $4 billion to $7 billion per year.
The concerns that acid rain legislation is intended to address are legitimate and
understandable. A number of rivers in Nova Scotia have lost most of their salmon over the past
forty years as they have become more acidic. Red spruce are dying on top of Camel’s Hump in
Vermont and Mount Mitchell in North Carolina. And there is no doubt that some fisheries in the
Adirondacks are in a bad way. From the turn of the century until the 1950s for instance, Lake
Colden was one of the best trout fly fishing lakes in the eastern United States. Teddy Roosevelt
fished there often and was vacationing at Lake Colden when President McKinley was shot.
Today, Lake Colden is highly acidic (pH 5.0) and nearly fishless. It is held up as the classic case
of acid rain’s destructiveness.
Recent research, however, suggests that acid rain has little or nothing to do with these
problems. Surveys of lakes in New England and New York show much less acidity than
anticipated, while other studies show that acid rain has very little effect on surface water acidity.
Perhaps most intriguing, studies of the fossil records in lake sediments reveal that many lakes
that are acidic today have been highly acidic for centuries, except for several decades in the late
19th century and early 20th century when they were unnaturally alkaline.