Philadelphia’s Storm-Water Management Plan – Implications for Development
Like many older cities, Philadelphia has a combined sewer and storm water system that can dump sewage into waterways – in its case, over 60% of the system. To meet state and federal clean water regulations, Philadelphia initiated plans starting in 1997 and culminating in the “Green City, Clean Waters” plan approved by the state in 2011. The plan includes code and water billing changes that improve water quality through retention and infiltration rather than through constructing parallel storm and sewer systems. The plan requires phased provision of 10,000 acres of new pervious surfaces at a cost projected to be $1.67 billion over the next 25 years – estimates for comparable installation of separated storm systems were “billions” higher. The driving force behind the plan was the simple economic fact that Philadelphia could not afford to build separated systems. Plan requirements and their consequences include:
