Where does all the water go in New York City?

Impervious surfaces cover approximately 72% of New York City, preventing rainwater to percolate into the ground.  As a result, a significant amount of stormwater ultimately flows into the city’s sewers, and in addition to stormwater, wastewater (also known as sanitary sewage) adds to this system.  As the most populous city in the United States with approximately 8.5 million residents, one may wonder where all of the water goes and how much the city’s infrastructure can handle it.  
Alarm bells are ringing for the state’s Department of Environmental Conservation (DEC), and they even acknowledge that the sewage and wastewater treatment facilities in the state are deteriorating. In fact, according to the DEC, about one quarter of the 610 facilities are operating beyond their useful lives. New York’s aging wastewater infrastructure is presenting many new challenges and will continue to for future generations. So what are some initiatives the city has taken to address this looming problem?  Although much of the infrastructure and water management largely remains a financial challenge, the city has invested in environmental and engineering projects that largely go unnoticed by many New-Yorkers and visitors alike.
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