Long Term Monitoring (LTM)

Determining the effectiveness of the Clean Air Act and Amendments for the recovery of surface waters in the northeastern US.

This research is part of the US EPA program to collect long-term data on the trends and patterns of response in surface waters sensitive to acidic deposition. Goals are to:

  1. document the changes and patterns in aquatic chemistry for defined sub-populations and sites that are known to be susceptible to acidification or recovery,
  2. evaluate linkages in changes in surface waters, if any, to changes in deposition that are related to regulatory goals;
  3. characterize the effectiveness of the Clean Air Act Amendments in meeting goals of reducing acidif­ication of surface waters and improving biologically-relevant chemistry in the northeastern US, and
  4. provide information for assessment of the need for future reductions in atmospheric deposition based on the rate of recovery (or not) of the systems under study.

For more information, check out the US EPA’s LTM/TIME site: https://www.epa.gov/airmarkets/monitoring-surface-water-chemistry