Storm Sewer System

For better understanding this layer was renamed from Storm Sewer System to Combined Sewer (CSS) Sewershed .The dataset contains locations and attributes of combined sewer system sewersheds within the DC Water jurisdiction. There are small areas within this dataset, between regulators/interceptors and the outfalls, that primarily serve as storm sewersheds. Combined flow should enter these areas only when it overflows from the interceptors. This data layer does not consider overlaps with the MS4 areas and where additional MS4 separations has taken place.为便于理解，该数据图层已从雨水管道系统(Storm Sewer System)重命名为合流制排水汇水区(Combined Sewer, CSS)。本数据集涵盖华盛顿特区水务局(DC Water)管辖范围内的合流制排水系统汇水区的位置与属性信息。数据集内存在部分位于排水调节设施/截流干管与排放口之间的小型区域，其主要功能为雨水汇水区；仅当合流污水从截流干管溢流时，此类区域才会接纳合流。本数据图层未考虑与市政独立雨水排水系统(MS4, Municipal Separate Storm Sewer System)区域的重叠情况，亦未纳入已实施额外MS4分流改造的区域。