The National Aquatic Resource Surveys: Providing Spatially-Extensive, Nationally Consistent Data

Following Executive Order 14072 issued in April 2022, the Office of Science and Technology Policy, Office of Management and Budget, and Department of Commerce published the final National Strategy to Develop Statistics for Environmental-Economic Decisions (National Strategy) in January 2023. One of the United States Environmental Protection Agency’s (EPA) contributions to this National Strategy will be to incorporate components of the National Aquatic Resource Surveys (NARS) into the corresponding water quality accounts. NARS are statistical surveys designed to assess the status of and changes in chemical, physical, and biological quality of the nation’s coastal waters, lakes and reservoirs, rivers and streams, and wetlands.  Using a probabilistic design to select sample sites across the conterminous U.S., these surveys provide successive snapshots of the overall condition of the nation’s water. The surveys use standardized field and lab methods to collect and analyze physio chemical, biological and recreational indicators, which enables comparison of results from different parts of the country and between years. EPA works with state, tribal, and federal partners to design and implement the National Aquatic Resource Surveys. The surveys are designed to answer questions such as: What percent of waters support healthy biological communities and recreation? What are the most common water quality problems? Is water quality improving or getting worse? Are investments in improving water quality focused appropriately? In addition to these design drivers, the NARS surveys have been or are being used to address a broad range of other questions including: ·         What is the condition of attributes of aquatic ecosystems at locations not sampled? ·         How do attributes of aquatic ecosystems respond to changes in stressors? ·         What are potential future benefits of achieving the Clean Water Act (CWA) goal of eliminating water quality impairments across the country? We will highlight examples of these additional uses, as well as examples of additional tools and resources in the presentation. Chemical, physical and biological data from more than 15,000 NARS sites and earlier pilot studies are available on EPA’s website at https://www.epa.gov/national-aquatic-resource-surveys/data-national-aquatic-resource-surveys. The consistent collection of co-located data and the probabilistic survey design make this a uniquely powerful dataset for analyzing patterns and interactions among these data and other landscape and climatic variables and making inferences about the condition of the broader population of waters across the U.S. EPA summarizes a set of core chemical, physical, and biological indicators relevant to ecosystem and human health and presents the results in national reports available at https://www.epa.gov/national-aquatic-resource-surveys/outreach-materials-national-aquatic-resource-surveys#reports. Results for a range of subpopulations can also be explored through interactive dashboards.

Impact/Purpose

This presentation will describe the content of NARS, EPA’s nationally consistent and comprehensive aquatic monitoring program to a group of distinguished economists who seek to quantify the value of aquatic ecosystems at national scale. As these data are the only set of nationally representative data it should be of great interest to this group. We expect that this will help to expand partnerships between NARS personnel and economists.

Citation

Mitchell, R., J. Corona, S. Holdsworth, S. Lehmann, A. Nahlik, AND P. Ringold. The National Aquatic Resource Surveys: Providing Spatially-Extensive, Nationally Consistent Data. Sixth Annual Workshop on Integrated Assessment Models and the Social Costs of Water Pollution, District of Columbia (DC), DC, October 11 - 13, 2023.