Integrated management of irrigation and urban storm-water infiltration

New microscale techniques have become available to assist urban designers in better water management. Urban water management has focused on two different areas: storm water and water supply. The focus of storm-water management is shifting toward low-impact development, which emphasizes better management of urban storm water through reductions in postdevelopment runoff by increasing on-site infiltration, while water supply planning has been enhanced by the emergence of end-use demand management, especially outdoor irrigation. Implementation of these two objectives requires examination of processes at smaller scales in order to evaluate changes being contemplated at a parcel level. A modeling approach is presented that incorporates decentralized options for management of both storm water and urban water supply. Management options that can be evaluated with this approach include restrictive irrigation policies and rainwater harvesting. A simpler model based upon Soil Conservation Service hydrology is then calibrated to the more complex model using a commercially available nonlinear optimizer. A method for comparison of costs and benefits from a consumer perspective is presented.