Wetlands are an edge of field practice that are strategically located in low lying areas to capture and treat runoff and tile drainage water from surrounding upland areas. Water treatment wetlands in the Upper Cedar can either be designed for a specific treatment area, or in some cases may restore natural wetlands that were previously converted to crop ground.
Wetlands are the undisputed champion of water quality practices because of their ability to treat a relatively large area in comparison to other edge of field structures - up to 300-500 acres depending on their size and location. In addition, wetlands offer important flood mitigation benefits and habitat for birds, amphibians and and numerous other wildlife species. Wetlands offer nitrate reductions of 52% on average, according to the Nutrient Reduction Strategy science assessment, with some reaching as high as 70-80% depending on size and location. Comparisons of inflow and outflow samples from one working wetland in the Middle Cedar showed a 84% reduction in nitrate concentration.
Several programs exist to offer fair compensation for landowners willing to install wetlands, including both long term and permanent easements.
Photos for the gallery below were taken by Joe Murphy, Senior Communications Manager for the Iowa Soybean Association.