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

Abstract

Increases in the frequency of floods are leading watershed planners to encourage practices that can attenuate surface runoff. Water detention practices that are distributed watershed wide are one approach being considered. Several water detention practices also provide wetlands that carry habitat and water quality benefits. How should planners set planning goals to realize these 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 included 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 established for water storage and new wetland areas, and progress toward 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 may optimize benefits may also 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 landscape-scale agricultural research crossing social and conservation disciplines.

Implementing constructed wetlands for nutrient reduction at watershed scale: Opportunity to link models and real-world execution

“…The ACPF tool proved a useful means of identifying potential build sites. ACPF is freely available and being used throughout the Midwest (Ranjan et al 2019;Tomer and Nelson 2020;Duncan et al 2021;Respess and Duncan 2021). We suggest that exploring potential wetland locations provided by ACPF results can be advantageous prior to performing subbasin discretization in SWAT for modeling constructed wetlands.…”

“…We compare modeled cost-effectiveness to realized cost-effectiveness. We present the results of SWAT modeling and applying the Agricultural Conservation Planning Framework (ACPF) (Porter et al 2018;Ranjan et al 2019;Tomer and Nelson 2020) independently of SWAT to identify suitable locations for constructed wetlands. The TMDL is being written for the upper East Fork of the Little Miami River watershed (UEFW) (OhioEPA 2021).…”

Agricultural Conservation Planning Framework: Watershed applications, research opportunities, and training resources

“…Other articles in this issue describe examples of ACPF applications: Gesch et al (2020) share the process used in Iowa to develop watershed plans. Tomer and Nelson (2020) combine analyses from several watersheds to support larger scale planning, and assess how ACPF data on distributed, landscape-based water detention practices may inform strategies for recruiting landowners to implement those practices, which can attenuate peak runoff rates.…”