An analysis at fivethiryeight.com by Brook Miner, a postdoctoral research fellow in ecology and evolutionary biology at Cornell University, reveals that while water bodies in the Northern Appalachians and Adirondacks are recovering from past acid rain pollution, “streams in western Virginia show little or no sign of improvement.”
Several Virginia streams have actually seen an increase in sulfate concentrations over time, says Miner, who analyzed 20 years of water chemistry data from more than 100 lakes and streams in the eastern U.S.
The explanation for why the Central Appalachians are not recovering like the streams and lakes to the north may have to do with geology. Miner cites a paper published last year by a team of researchers at the University of Virginia. They hypothesized that because Virginia’s soils are older and “stickier” than northern soils, they retained much of the sulfate from acid rain, preventing it from entering water bodies quickly. While this helped to keep sulfate levels lower in the early 1990s, the soils are now leaching the sulfate into the watershed.
According to Miner, “The soils of the central Appalachians will continue to release sulfate into the water for years to come, but lower additions from man-made sources in the present would decrease the burden on ecosystems haunted by the ghost of emissions past.”