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The 2002 National Assessment Database


The 2002 National Assessment Database summarizes information submitted electronically by the states in 2002. This is EPA's first-ever interactive summary of state-reported water quality information. It allows you to view assessments of individual waterbodies. It presents data in a format designed for quick reference by water quality professionals and those familiar with water quality reporting. EPA will continue to work with them to improve electronic reporting for the 2004 cycle and beyond.


Every two years, states submit water quality reports to the U.S. Environmental Protection Agency (EPA) under Section 305(b) of the Clean Water Act. In the past, states submitted these reports in hard copy, and EPA compiled them in a Report to Congress ( States also provided, under Section 303(d) of the Clean Water Act, a separate prioritized list of waters ( that were impaired and require pollution controls.

Beginning with the 2002 reporting cycle, EPA urged states to combine these two reporting requirements into one Integrated Report and to submit their reports electronically. Few states submitted fully integrated reports for the 2002 cycle, although more are expected to do so in future reporting cycles. In order to increase the usefulness of this information to the public, EPA is presenting the 2002 state-reported electronic assessment information (which does not include Section 303(d) information prioritizing impaired waters) through this National Assessment Database.

When they assess water quality, states and other jurisdictions compare their monitoring results to the water quality standards ( they have set for their waters. Water quality standards consist of three elements: the designated uses assigned to those waters (such as public water supply, recreation, or shellfish harvesting), criteria to protect those uses (such as chemical-specific thresholds that should not be exceeded), and an anti-degradation policy intended to keep waters that do meet standards from deteriorating from their current condition.

From the 2002 National Assessment Database (, you can click on the highlighted states to find summary information and assessment results for specific watersheds and waterbodies of interest. For all states, click on a link to the state water quality webpage for additional information. top

About the Database

This National Assessment Database summarizes water quality reports submitted electronically by the states to EPA for the 2002 reporting cycle. When reviewing the findings, it is important to keep in mind that this information is not comparable across states or to earlier Section 305(b) reports, so it is not appropriate to use the information to find trends in statewide or national water quality.

There are many reasons for this lack of comparability. The methods states use to monitor and assess their waters (including what and how they monitor) and how they report to EPA on their findings vary from state to state and even over time. Many states target their limited monitoring resources to waters that they suspect are impaired or to address local priorities and concerns. Therefore, the small percentage of their waters they assess may not reflect conditions in state waters as a whole. They may monitor a different set of waters from cycle to cycle. Even weather conditions - such as prolonged drought - can have an impact on whether waters meet their standards from one year to the next.

In addition, the science of monitoring and assessment itself changes. For example, increased fish tissue sampling is resulting in more extensive and protective fish consumption advisories, although water quality conditions themselves may not have changed. Thus, in fact, states are improving their ability to identify problems as monitoring and analytical methods improve.

The state 305(b) reports are useful to the public and decision makers for the insight they provide into the comparatively small number of assessed waters in each state. However, an understanding of national water quality conditions and trends is best determined by scientifically-based studies designed to sample water quality conditions at randomly selected sites that are statistically representative of the Nation's many distinct ecological regions. EPA and its monitoring partners have developed the National Coastal Condition Report II ( using this methodology. A probability-based Wadeable Streams Assessment ( is currently underway to determine the biological condition of small streams in the U.S. The information in the National Assessment Database is different from the previous 305(b) reports for other reasons as well:

  • 2002 was a transition period between traditional 305(b) reporting and integrated 305(b)/303(d) reporting. Where states included 303(d) assessment information, they may have relied on stringent rules for data sufficiency and data quality and so reported fewer waters assessed than in the past.
  • The Database contains only electronically-reported, waterbody-level information from the states. A few states conduct probability-based surveys of their waters to supplement waterbody-specific information. EPA strongly encourages the use of probability-based surveys because they will increase our understanding of water quality conditions over broad areas of the U.S., including those that were assessed before. However, results of those surveys are not yet included in this Database.
  • Each state's definition of its designated uses (for example, Warm Water Fishery or Livestock Watering) may differ from those used by other states. EPA has collected them into a set of national categories that are somewhat different from those used in previous national 305(b) reports. National categories used in this Database are those defined in EPA's Water Quality Standards Database (
  • To learn more about the practices of specific states, visit the state's water quality web site and to read the explanatory and programmatic information included in most reports. The Database contains the URLs for those web sites. top

Future Reporting

For many years, water quality monitoring, assessment and reporting in the United States suffered from inconsistencies in state programs and methods, lack of scientifically-defensible national-level information that could be used to track water quality changes over time, and insufficient information to determine the effectiveness of the Nation's water pollution control programs. Integration of the water quality monitoring and reporting requirements ( under Sections 305(b) and 303(d) is a step toward streamlining and improving this program.

EPA will soon issue guidance to the states to clarify integrated reporting requirements for the 2006 reporting cycle. EPA expects improved water quality reporting in the future, both as states continue to integrate their Section 305(b) and 303(d) reports and as electronic reporting becomes more established. We will continue to adapt and refine the National Assessment Database so that it captures the full extent of state monitoring activities. Both EPA and the states are developing long-term monitoring strategies that will identify specific actions needed to move toward more comprehensive and consistent reporting of water quality conditions across the country.

The 2002 state-reported information presented in the National Assessment Database is a first step toward more consistent national reporting. To improve monitoring and assessment programs and our understanding of water quality conditions (including trends over time), EPA and the states have also embarked on probability-based studies of our Nation's water resources.

  • The National Coastal Condition Report ( is a foundation for EPA's efforts to protect, manage, and restore coastal ecosystems. It uses nationally consistent methods and a probability-based design to assess five key indicators of coastal water health.
  • In 2004, EPA and the states launched a national survey of the biological health of wadeable streams. In 2005, this Wadeable Streams Assessment ( will provide a scientific baseline of stream water quality based on 1,100 randomly-selected sites across the country. top


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