PS 21-42
Measuring ecosystem services value of wetland mitigation acres in the United States
Section 404 of the U.S. Clean Water Act includes most wetlands in its jurisdiction and requires wetland mitigation to compensate for permitted wetland losses. Most studies that evaluated the effectiveness of the mitigation program did not adequately quantify and monetize the ecosystem services value of these restored wetlands. Usually only a single ecosystem value perspective is adopted, whereas we know most wetlands often provide multiple ecosystem services. These services when left unquantified often results in an implicit value of zero being placed on the resource, which can result in ecosystem services being given too little weight in policy decisions. Under the assumption that mitigation requirements reported in the Army Corps wetland permit files reflect actual wetland creation, ecosystem services value is estimated using a wetland meta-function transfer approach. Mitigation data reported in the permit files for the years 2010-2012 are analyzed. The economic approach accounts for potential issues related to the heterogeneity of the environmental resources and economic instruments considered in wetland valuation, providing robust wetland valuation estimates.
Results/Conclusions
We find that recreation, water quality services, water supply, and commercial fishing are relatively highly valued services associated with wetlands. The results indicate that cumulative ecosystem services value of wetlands in the U.S. is in the range of $5,000 to $70,000 per acre per year. These per acre values translate to a nationwide aggregate (total mitigation acres) benefit of $2.7 billion per year. Given the history of the ecosystem services not fully captured nor adequately quantified, the current analysis is an initial step in understanding the value of wetland mitigation. While there is now widespread recognition that wetlands provide valuable ecological services, there remain substantial debates about the extent to which resources should be allocated for their protection, restoration. The current analysis helps underscore the importance of wetlands restoration and protection.