Measurements of landscape capacity for water detention and wetland restoration practices can inform watershed planning goals and implementation strategies

Authors: Tomer, Mark; NELSON, JESSICA - Iowa State University

Submitted to: Journal of Soil and Water Conservation
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/20/2020
Publication Date: 7/6/2020
Citation: Tomer, M.D., Nelson, J.A. 2020. Measurements of landscape capacity for water detention and wetland restoration practices can inform watershed planning goals and implementation strategies. Journal of Soil and Water Conservation. 75(4):434-443. https://doi.org/10.2489/jswc.2020.00110.
DOI: https://doi.org/10.2489/jswc.2020.00110

Interpretive Summary: Watershed planning goals often aim to mitigate peak runoff flows using distributed water detention practices, several of which also create wetlands that provide habitat and water quality benefits. This editorial examines how precision siting of practices can provide data for evaluating watershed planning goals and assessing how implementation strategies may influence chances of success in reaching those goals. In three HUC12 watersheds within Minnesota’s Yellow Medicine River, the Agricultural Conservation Planning Framework (ACPF) toolbox was used to identify places where water and sediment control basins (WASCOBs), depressional (prairie pothole) wetlands, and nutrient removal wetlands could be installed. Results were summed to represent a ‘landscape capacity’ for storing water and creating wetlands in each watershed. These capacities were plotted with interim (10 year) watershed planning goals for water storage and wetlands, and progress towards reaching these goals was estimated assuming implementation of 30 wetland practices, selected either at random or by prioritizing sites based on water volume, wetland size, or runoff-contributing area. Results showed a random ranking could be effective in reaching at least one interim (10 year) planning goal in each watershed. The ACPF watershed planning products helped evaluate planning goals and whether recruitment strategies for implementation need to target larger, priority sites to ensure success. The question is important because targeted recruitment of a few, large sites with greater benefits may be difficult to implement for social and/or logistical reasons. Whereas, open enrollment strategies, if successful in the interim, can also demonstrate new practices to enhance social acceptance for greater future conservation progress. These results, which suggest an avenue for collaborative research among social and conservation scientists, will be of interest to agricultural conservationists and policy analysts.

Technical Abstract: Watershed planning goals often aim to mitigate peak runoff flows using water detention practices distributed watershed wide. Several water detention practices also create wetlands that carry habitat and water quality benefits. This editorial examines how precision siting of practices can provide data for evaluating watershed goals and assessing how implementation strategies may influence chances of success in reaching those goals. In three HUC12 watersheds representing different landscape regions of Minnesota’s Yellow Medicine River, the Agricultural Conservation Planning Framework (ACPF) toolbox was used to locate sites suited for installation of water and sediment control basins (WASCOBs), depressional (prairie pothole) wetlands, and nutrient removal wetlands. Tabulated attributes for sited practices include water storage capacities (volume), and potential wetland areas, which were summed to represent a ‘landscape capacity’ for storing water and creating wetlands in each watershed. These capacities were plotted with interim (10 year) watershed planning goals for water storage and new wetland areas, and progress towards reaching these goals was estimated assuming implementation of 30 wetland practices, selected either at random or by rank when prioritizing sites based on water-storage volume, wetland size, or runoff-contributing area. Results indicated that a random ranking could be effective in reaching at least one interim (10 year) planning goal in each watershed. Results show ACPF watershed planning products can be used to evaluate planning goals and whether recruitment strategies for implementation need to target larger, priority sites to ensure success. The question is important because targeted recruitment of a few, large sites that optimize benefits may be difficult to implement for social and/or logistical reasons. Whereas, if open enrollment strategies can be successful over interim planning windows, they can also demonstrate new practices to enhance social acceptance for broadening future conservation benefits. Results suggest an avenue for collaborative research among social and conservation scientists.