This document discusses strategies for restoring the built environment to better manage stormwater runoff. It provides examples of how existing development in Philadelphia alters the natural water balance by increasing runoff and decreasing groundwater recharge. Various case studies and projects are described that implement green infrastructure techniques like rain gardens, green roofs, porous pavements, and cisterns to slow, spread, and sink stormwater runoff on site. Challenges to changing practices include local regulations, construction knowledge, maintenance needs, and aesthetic preferences.