The International Information Center for Structural Engineers

Items filtered by date: Wednesday, 15 November 2017

New York City, like other older urban communities, is largely serviced by a combined sewer system where storm water and wastewater are carried through a single sewer line to the city’s 14 treatment plants. These facilities can manage and treat all the wastewater produced in the city on a dry weather day (1.3 billion gallons on average) and also have the capacity to clean more than twice the dry weather flows on a rainy day. But during intense precipitation events, the storm water exceeds this capacity and overflows can be discharged into local waterways. In an effort to improve water quality, the city’s Department of Environmental Protection (DEP) is building rain gardens, designed to absorb polluted storm water that would otherwise end up into the sewer system.