Watershed Systems Analysis for Urban Storm-Water Management to Achieve Water Quality Goals

Systems analysis can assist in decision making to achieve water quality goals in urban watersheds that are typically associated with streams having poor water quality and degraded aquatic habitats caused by storm-water runoff. The need for an effective systems analysis methodology is particularly urgent in watersheds facing regulatory action through the imposition of a total maximum daily load (TMDL). Systems analysis methodologies are available that approach the problem at different levels of complexity corresponding to the methods that are used to model the physical, technological, and economic aspects of watershed storm-water management. Important roles exist for both simulation and analytical optimization, and they can be used together in ways that improve the applicability of both. These tools, along with geographic analysis and field monitoring, are used in a four-stage process that can lead to the development of a cost-effective strategy for moving an impaired watershed toward the restoration of water quality and removal of the impaired status. Details of the methodology are described, and results are presented from its successful application in the development of an action plan for an impaired watershed that drains multiple municipalities in suburban Philadelphia, PA. (C) 2013 American Society of Civil Engineers.