2024 Report and Results Page

2024 Acid Rain Monitoring (ARM) Report and Results

Welcome to the 2024 Acid Rain Monitoring (ARM) Report page. We are committed to providing detailed and clear information on the impacts of acid deposition on Massachusetts' surface waters. This year's report marks the 23rd year of Phase IV of the Acid Rain Monitoring Project, an initiative launched in 1983.

Executive Summary

Supported by the Massachusetts Department of Environmental Protection and led by the Water Resources Research Center at the University of Massachusetts Amherst, the Acid Monitoring Project—a ground-breaking initiative that began in 1983 to evaluate the effects of acid deposition on surface waters across Massachusetts—entered its 23rd year in 2024. This year, 45 volunteers from 33 towns statewide sampled 146 water bodies, with analysis conducted at the UMass Environmental Analysis Lab and 9 additional volunteer-staffed labs located from Westfield to the Cape Cod National Seashore, including labs such as the MWRA Quabbin Lab in Belchertown and the Springfield Water and Sewer Commission lab in Westfield. Long-term sites, with data dating back to at least 1985, underwent detailed analysis for color and 11 ions (Cl, NO3, SO4, Mg, Mn, Fe, Cu, Al, Ca, Na, K). Of the 26 long-term sites, 25 were accessible for analysis, with one site remaining inaccessible for the year.

Key Findings

pH and Alkalinity Trends

• 29% of surveyed water bodies exhibited a notable increase in pH.
• 29% showed a significant rise in alkalinity.
• 7% of water bodies exhibited a decrease in pH.
• 10% displayed a significant downward trend in alkalinity.

Ion and Color Analysis for Long-Term Sites

• Sodium (Na) and Potassium (K): Significant increases observed, likely influenced by road salting practices.
• Chloride (Cl): Increased at 17 sites, associated with road salting and industrial discharges.
• Color: Increased at 20 sites, potentially indicating a recovery of natural alkalinity or changes in organic matter concentrations.
• Sulfate (SO4): Decreased at 25 sites, reflecting the positive impact of reduced industrial emissions.

Correlation Analysis from Heatmaps

Our detailed correlation analysis, visualized through heatmaps, provides deeper insights into the relationships between various water quality parameters across long-term monitoring sites from 1983 to 2024. Key observations include:

Strong Positive Correlations

• Calcium (Ca) and Magnesium (Mg): Across most sites, there is a strong positive correlation between calcium and magnesium, suggesting that these elements often occur together in higher concentrations due to similar sources such as geological formations and agricultural runoff.
• Sodium (Na) and Chloride (Cl): A common strong positive correlation exists between sodium and chloride, typically attributed to road salt application and industrial discharges.

Strong Negative Correlations

• Color and Sulfate (SO4): Many sites exhibit a strong negative correlation between color and sulfate, indicating that higher levels of dissolved organic matter are associated with lower sulfate concentrations.
• Nitrate (NO3_N) and Iron (Fe): Some sites show a negative correlation between nitrate and iron, suggesting that higher nitrate levels might be associated with lower iron concentrations due to redox conditions in the water.

Neutral or Weak Correlations

• Aluminum (Al): Often shows weak correlations with other elements, reflecting its independent behavior in the water.
• pH and Sulfate (SO4): A weak negative correlation was observed, indicating that higher sulfate concentrations tend to be associated with lower pH levels.

Methods

Sampling Design and Procedures

• Sampling occurred on April 7, 2024, with challenging weather conditions.
• Volunteers collected surface water samples from 146 sites across Massachusetts, ensuring accurate representation.
• Detailed protocols were followed for sample collection and laboratory analysis to maintain data integrity.

Laboratory Analysis

• Analysis conducted at the UMass Environmental Analysis Lab and 9 additional volunteer-staffed labs.
• Long-term sites underwent detailed analysis for color and 11 ions, providing a comprehensive view of water quality trends. The UMass Extension Soils Laboratory analyzed long-term site samples for cations, while the University of New Hampshire’s Water Quality Analysis Laboratory analyzed samples for anions.

Volunteer Network

The Acid Rain Monitoring Project relies on the dedication of volunteers. This year, 45 volunteers from 33 towns participated in the sampling efforts, contributing to the success of the project. Their involvement is crucial for maintaining a broad and detailed understanding of water quality across the state.

Full Report Access

For a detailed analysis and comprehensive data, the full 2024 Acid Rain Monitoring Project Annual Report is available. Access the full report here.

Conclusion

The 2024 report highlights the importance of continuous monitoring and adaptive management strategies to address the ongoing impacts of acid deposition. The data collected provides valuable insights into water quality trends and informs future environmental policies and practices.

Thank you for your continued support and interest in our environmental monitoring efforts. For more information, please contact the Water Resources Research Center at the University of Massachusetts Amherst.