Nutrient Indicators Dataset

The Nutrient Indicators Dataset (NID) presents information on states’ efforts to minimize nutrient pollution. It is a large, detailed dataset that identifies, state-by-state, significant sources of nutrient pollutants – nitrogen and phosphorous – that enter bodies of water, which EPA expects to update annually.

Water Quality Assessment and Total Maximum Daily Loads Information (TMDLs)

Water Quality Assessment and TMDLs are information reported by the states to EPA about the conditions in their surface waters. This information is required every two years under Clean Water Act Sections 305(b) and 303(d).

Clean Air Status and Trends Network (CASTNET)

This is a national, long-term atmospheric monitoring network designed to provide data to assess trends in air quality, atmospheric deposition, and ecological effects due to changes in air pollutant emissions. Established in 1987, CASTNET now measures atmospheric nitrogen concentrations, ozone, and nitrogen deposition flux at more than 80 sites throughout the U.S. and Canada.

Monitoring Surface Water Chemistry (Temporally Integrated Monitoring of Ecosystems and Long Term Monitoring)

Surface water chemistry is a direct indicator of the potential effects of acidic deposition and the overall health of aquatic ecosystems. Two EPA administered monitoring programs provide information to assess the response of acid-sensitive watersheds most impacted by acidic deposition: the Temporally Integrated Monitoring of Ecosystems (TIME) project and the Long-Term Monitoring (LTM) project.

EPA Nitrogen Oxide Emission Monitoring

EPA Nitrogen Oxide Emission Monitoring is a long-term dataset of monitored nitrogen oxide emissions from power plants. Data are collected as part of EPA’s emissions trading programs.

National Atmospheric Deposition Program (NADP)

NADP Exitis a national, long term program that monitors nitrogen and other pollution in precipitation. The program is a cooperative effort between many different group, including EPA and other federal agencies, state, tribal and local governmental agencies, educational institutions, private companies, and non-governmental agencies. Established in 1977 to measure atmospheric deposition its effects on the environment, NADP serves as a complement to CASTNET. It consists of five sub-networks, including the National Trends Network which measures precipitation chemistry at more than 250 sites throughout North America, and the Ammonia Monitoring Network, which is the only network providing a consistent, long-term record of ammonia gas concentrations across the United States.

National Water-Quality Assessment Program: Regional SPARROW Model Assessments of Streams and Rivers

SPARROW Exitmodels for each of the seven regions have been incorporated into an interactive, online decision support system so that water managers, researchers, and the general public can access SPARROW models and map predictions of long-term average water quality conditions, track transport to downstream receiving waters, and evaluate management sourcereduction scenarios.

The Environmental Monitoring and Assessment Program (EMAP)

EMAP was a research program run by EPA's Office of Research and Development to develop the tools necessary to monitor and assess the status and trends of national ecological resources.

Environmental Monitoring and Assessment Program Data

The Environmental Monitoring and Assessment Program Data page provides a list of links to EMAP and other environmental monitoring and assessment data websites.