Vermont's water quality issues can seem like an insurmountable problem, but state scientists have a treasure-trove of acid rain data that could prove useful in tackling those concerns.
Decades before phosphorus levels in Lake Champlain and nitrogen levels in the Connecticut River were making headlines, scientists were raising concerns about acid rain – and they started doing something about it.
In the 1980s, scientists with the Vermont Department of Environmental Conservation started taking samples of water from acid-impaired lakes and ponds and tracking all sorts of data. And they’ve been doing it ever since.
These days, it’s Rebecca Harvey’s job.
"What we’re finding is that acidity is a really complicated issue, and recovering from acid impairment is really complicated," says Harvey. "What’s been really astounding is that we can show, with our data set, the effectiveness of the Clean Air Act and its regulations on emissions. So, the Clean Air Act regulates air quality, but we’re seeing the impact in the quality of our streams."
Amendments made in 1990 to the federal Clean Air Act put emission restrictions on coal-fired power plants, which were identified as a major cause of acid rain. Remote, high-elevation lakes and ponds were among the most affected water bodies in Vermont.
Harvey takes samples from a dozen of those out-of-the way places, including Hardwood Pond, in Elmore. This time of year she straps on cross-country skis to get there, traversing a field then down a wooded trail to the outlet stream where she takes her samples when the pond is frozen over.
Harvey samples year-round, but she says this time of year yields particularly valuable data for the state and the federal Environmental Protection Agency.
"We have committed to the EPA, 'cause this is an EPA-funded program, to come out three times in the spring to try to catch that acid shock – so that time when the snow is melting and all of the acid content in the snowpack is melting and releasing its acidity to the pond, and also all of the brooks and the waters downstream," Harvey explains.
Vermont Department of Environmental Conservation Commissioner Emily Boedecker says big changes in acidity can have a drastic effect.
"Now it’s an issue for a lake itself," Boedecker says. "If the pH changes substantially, it has impacts on the fish and other aquatic life in the lake. But also, the lakes that we were testing have been very specifically chosen because they’re in very isolated locations.
"And these 12 lakes in the state are really only influenced by what’s coming in atmospherically and changes in climate. There’s no development around. There’s no logging, there’s no roads. So that gives us a very good opportunity to clearly measure what are the atmospheric pollutants that are coming to us from other states."
Boedecker says this monitoring also gives scientists long-term information on Vermont lakes and ponds that aren’t affected by runoff of farm fertilizers, road salt and other pollutants.
"So having long-term monitoring is really key to proving the results that we’re getting, either here with acidification of our lakes and atmospheric deposition, or with the other major initiative that we have, to address phosphorus pollution in our lakes," says Boedecker.
Back at Hardwood Pond, as Harvey packs up her instruments, she says she’s impressed with the foresight of the scientists who came before her.
"To think of starting this program 40 years ago, I just think is amazing to have that idea," she says. "To say, ‘You know what, we gotta to start collecting these data and measuring the water quality so that we can track how things are changing with time.'"
Harvey says the more they study water quality, the more questions arise. Fortunately, nearly 40 years of data is on the books to help answer some of those questions.