The City as a whole consists of a combined and separate sewer system.
The combined system during dry-weather directs sanitary sewer flows to the Wastewater Treatment Plant "WWTP" for appropriate treatment in accordance with the City's SPDES permit. During wet-weather, diversion structures are inundated due to the addition of stormwater to the system. Dependent of the severity of the storm event, the combined flows may be diverted to one of 13 permitted discharge points along the Hudson River and the Quassaick Creek. Approximately 68% of the City conveys stormwater flows to the combined system.
The separate sewer system does not collect or convey sanitary swage and only contain water during and shortly after storm events, unless the structures are under the influence of groundwater. Approximately 32% of the City conveys stormwater to one of 283 identified outfalls.