Introduction

How clean are our nation's air, water, and land? How healthy are its people and ecosystems? How can we measure the success of policies and programs to protect health and the environment?

This report provides the U.S. Environmental Protection Agency's (EPA's) response to these questions, with the aim of sparking a broader dialogue and discussion about how to answer them in the future. The report has two key purposes:

• To describe what EPA knows—and doesn't know—about the current state of the environment at the national level, and how the environment is changing.
  
  
• To identify measures that can be used to track the status of and trends in the environment and human health, and to define the challenges to improving those measures.

This report is the first step in EPA's Environmental Indicators Initiative. Launched in November 2001, this initiative seeks to develop an improved set of environmental indicators that will enable EPA to better manage for results and better communicate the status of the environment and human health. These indicators will provide critical tools for EPA to define environmental management goals and measure progress toward those goals. Early drafts of this report have already been helpful in developing EPA's strategic plan for 2003 to 2008.

An important next step in EPA's initiative will include working closely with partners—other federal agencies, states, tribes, local government, non-governmental organizations, and the private sector—to create a long-term strategy for developing an integrated system of local, regional, and national indicators. This report is issued as a draft to stimulate dialogue and invite input into developing and improving environmental measures in the future. EPA welcomes your suggestions about how well this report communicates environmental status and trends and how to better measure and manage for results. To learn more about the initiative and to provide your comments and feedback, please visit http://www.epa.gov/indicators/.

Using Indicators to Measure Results

This report uses the lens of environmental and health indicators to bring the current state of the U.S. environment into focus. Environmental indicators are measures that track environmental conditions over time. For example, they help measure the state of air, water, and land; the pressures on those resources; the status of human health; and the integrity of our nation's ecosystems. Examples of environmental indicators include concentrations of criteria air pollutants in ambient air, the extent of wetlands, and the levels of lead in the blood of Americans.

Environmental and human health indicators focus on outcomes—actual environmental results, such as cleaner air and water or improved human health or ecosystem condition—rather than on administrative actions, such as the number of permits issued. At one time, administrative measures of performance were considered sufficient indicators of progress. While administrative measures track what actions have been taken, they don't tell us whether those actions actually improved the environment or human health. Understanding the effectiveness of environmental programs, and measuring actual progress, requires indicators of health and environmental conditions.

Exhibit i-1 depicts this “hierarchy” of measures. Levels 1 and 2 are indicators of “response”—government administrative actions, such as the issuing of discharge permits, and responses to those actions. Level 3 indicators measure pressures on the environment, such as changes in the quantities of discharges to water. Levels 4, 5, and 6 all measure the state of the resource—such as changes in ambient levels of a pollutant or changes in the health of an ecosystem. To link environmental protection with real-world results, indicators and performance measures at each level of the hierarchy are required.

Exhibit i-1: Hierarchy of Indicators
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This report focuses, where possible, on indicators that describe environmental status and trends at a national level. In many cases, however, national-level indicators do not yet exist or are not supported by adequate data. In some of these cases, local and regional indicators do exist and are featured as examples in this report; these indicators are valuable for a number of reasons. They serve as examples of what national indicators might look like in the future. They provide important perspective on conditions at the local and regional levels, they are critical to understanding cause-and-effect relationships in the environment, and they provide an important tool for local decision-making.

About This Report

This report is organized around five core chapters (see chart below). The first three describe the current state of the primary components of the physical environment—air, water, and land—and the principal stressors that can affect their conditions. The final two chapters present indicators on human health and ecological condition.

The report was driven by a series of questions, developed by EPA, that address three themes: what is happening, why is it happening, and what are the effects. For example, in the area of outdoor air, the questions address the quality of the nation's air (what is happening), the factors contributing to outdoor air pollution (why), and the human health and ecological effects of outdoor air pollution (what are the effects).

Once the questions were developed, EPA examined data sources to identify potential indicators to address these questions on a national level. Scientists from inside and outside EPA then screened these indicators for their scientific soundness and relevance to the questions. Only indicators judged to be scientifically sound were included in this report. The questions posed in each chapter, and the indicators selected to answer them, are listed in Appendix A. Chapter 6 describes some of the challenges in developing and using indicators at the national level. The scientific foundation and more detailed information for the indicators listed in this report are presented in the accompanying Technical Document.

This report provides significant information about the nation's environment; however, its scope is limited in several ways. First, the report focuses primarily on the U.S.; it does not address international environmental conditions or issues that may affect environmental quality in this country. Second, the report provides information on status and condition, but does not describe the many important initiatives that EPA and its partners are undertaking to protect the environment and human health. More information about specific program initiatives and other indicator-related background materials, as well as links to EPA partners, can be found online at http://www.epa.gov/indicators/.

Introduction
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