Test ability to apply green infrastructure design principles to retrofit urban stormwater systems for reduced runoff and improved water quality. Scope includes site assessment, selection and justification of GI practices (bioretention, permeable pavement, green roofs, swales, tree trenches), basic hydrologic sizing and infiltration calculations, pollutant removal mechanisms, maintenance and monitoring plans, cost-benefit and regulatory considerations, and stakeholder coordination. Quiz-takers should design a retrofit scenario, estimate performance improvements, and propose practical implementation and upkeep strategies.