In land-limiting situations, constructed wetlands have the advantage of reducing the nutrient concentration prior to land application of the wastewater. This reduces the amount of land area required for waste disposal for a given livestock or poultry operation. It also has potential for reducing odors during land application. The recycled water from a wetland is suitable for barn flushing systems. Constructed wetlands can provide aesthetic purposes such as increasing wildlife populations.
Disadvantages Constructed wetlands are currently controversial.
Appropriate vegetation and uniform flow through the cells have been difficult to establish. While data from some sources have indicated very good treatment efficiencies, the performance of typical wetlands have been very erratic. Currently, a constructed wetland will be an extra cost for added treatment of wastewater from lagoons or holding ponds. Many sites do not have the soil or geologic properties to effectively serve as a wetland. Slope, topography, depth of soil, depth to bedrock, permeability and the size of area to be devoted to the constructed wetland could be limiting factors.