NYC DEP has invested over $1.5 billion in green infrastructure to reduce combined sewer overflows (CSOs) that discharge untreated sewage and stormwater into local waterways. Green infrastructure includes rain gardens, bioswales, permeable pavement, green roofs, and stormwater retention systems. These installations capture and absorb rainwater before it enters the sewer system, reducing the volume of combined sewage that overflows during storms. The program has installed over 11,000 green infrastructure assets across the city, with a focus on neighborhoods with the highest CSO volumes.