NH DES: Acid Rain Levels Dropping

The New Hampshire Department of Environmental Services (NHDES for people who need to breathe) recently published an interesting report regarding acidity levels in rain, lakes, and ponds. Strap on your snorkels and leave your umbrellas at home everyone, because the results indicate that acid is leaving the rain and the water.

Since the program began in 1972, 1,500 precipitation events (snow, rain, hail, etc.) have been monitored to measure their acidity levels. The pH of precipitation events has increased greatly (meaning it’s become more basic as opposed to acidic) while the level of substances that make things more acidic, such as sulfates and nitrates, have greatly decreased. This corresponds with a national reduction in atmospheric emissions of sulfur and nitrogen oxides over the same period of time.

“We are seeing, on a local and national level, the very positive long term benefits of the federal Clean Air Act Amendments of 1990 and our own state laws to reduce sulfate and nitrate precursors emitted into the air,” said Tom Burack, the commissioner of the NH DES. “Since 1994, our in-state emissions of sulfur dioxide and nitrogen dioxides from our industrial sources have decreased by 95 percent and 88 percent, respectively.”

Even the water down on Earth is getting in on the action; results of annual water samples collected since the early 1980’s show that sulfate and nitrate concentrations have significantly dropped in almost all water bodies. Based on analysis of nearly 2,000 water samples, pH and ANC (acid neutralizing capability) have either improved or stayed the same.

All these results are consistent with research funded by the U.S. Environmental Protection Agency, the U.S. Geological Survey, and the Hubbard Brook Research Foundation. Their own results also reported notable declines in sulfate and nitrate concentrations in the Northeast, with stable or improved pH and ANC levels.

Though these results are encouraging, these positive changes are occurring slowly. Continued monitoring is required and will allow NHDES to keep track of future water quality improvements and recovery in the future, and preserve the robustness of these long-term data sets.

“We still have opportunities to further reduce the air emissions that contribute to acid rain on a national level, particularly from the electric power generation sector, under anticipated future federal actions to reduce emissions that contribute to healthy ozone levels as well as climate change,” Burack noted. “The continued transition to a cleaner power sector on a national level will drive future emission reductions. Our new report confirms that cleaner air results in cleaner water, so as a downwind state New Hampshire’s environment will benefit from a cleaner power sector.”