Modeling biological condition to support valuation of aquatic ecosystems at a national scale

This STICS entry is for the slides. No abstract submitted. However, below is the description on the EPA's Water Research Webinar Series website (https://www.epa.gov/water-research/water-research-webinar-series): EPA estimates the benefits of preserving aquatic resources using the water quality index (WQI). The WQI focuses on metrics related to human use, such as recreation, but fails to fully capture aspects important to nonuse values of aquatic ecosystems, such as existence values. Stated preference surveys can quantify the nonuse values of streams and lakes but require an appropriate index of biological health to be able to measure and compare biological condition. In a recent effort, EPA researchers identified an appropriate biological health index to be applied in a forthcoming national stated preference survey that will estimate nonuse values of streams and lakes throughout the conterminous United States (CONUS). Through a literature review and focus groups, researchers compared two aquatic indices that are regularly used to quantify biological health by EPA’s National Aquatic Resources Surveys: 1) multimetric indices (MMIs) and 2) the observed-to-expected ratio of taxonomic composition (O/E). This webinar will discuss this comparison, implications for estimating benefits of preserving aquatic resources, and forthcoming work to link O/E with water quality and habitat models, which would forecast changes in O/E resulting from future regulatory action. 

Impact/Purpose

The US Environmental Protection Agency (EPA) conducts economic analyses as one means to evaluate proposed regulations under the Clean Water Act. Current practice uses a Water Quality Index (WQI) to compare management scenarios to determine potential benefits and costs to society. While the existing WQI capture non-use values to some extent, we cannot quantify use and non-use values separately. A range of research has shown that non-use values can be quite large, so quantifying them can be of critical importance to EPA decision making. In this public presentation, we will describe research to identify an index of biological health (i.e., condition) to act as a companion to the WQI that can help the EPA estimate benefits associated with non-use values. Previous work has also shown that the willingness of the public to pay for (or accept) water quality regulations depends on current water quality near them. Thus, interpolated values of biological condition can help us refine our estimation of non-use value by accounting for how biological condition varies regionally across the US. Therefore, we report on the development and application of preliminary models to interpolate values of this selected indicator to streams and lakes across the conterminous US. Finally, a next objective of this work is to explore whether modeling can be conducted to link management scenarios to improvements in biological condition to support benefits estimation. We will discuss several existing modeling approaches and the benefits and drawbacks of each for this effort. This research supports work being conducted in collaboration with economist in the EPA’s National Center for Environmental Economics. It also supports a deliverable under SSWR 1.2.2 - Interpolation and stressor-response analyses that extend the use of NARS data to support regulatory program needs. 

Citation

Hill, Ryan A. Modeling biological condition to support valuation of aquatic ecosystems at a national scale. Oregon State University Water Resources Policy and Management Virtual Seminar, N/A, Virtual, November 10, 2021.