The focus of this research was the development of a spatio-temporal model of a constructed wetland that can be used to evaluate policy elements and design practices from the perspective of wetland sustainability. The model was calibrated with data obtained from a wetland that treats runoff from an agricultural field. Sustainability metrics were developed to reflect an array of wetland functions including wildlife habitat, flood control, downstream hydrologic regime, wetland water balance, groundwater recharge and baseflow maintenance, aesthetics, and water quality functions. The model can be optimized by the user across this array of wetland functions, each of which was defined in terms of metrics relevant to sustainability. Stakeholders will be able to weight the metrics for each of these wetland functions in order to maximize sustainability for their specific goals. Optimally, this model will aid design engineers and policy makers in designing constructed wetlands as a function of necessary functions, location, and influent water quantity and quality characteristics.