Hydrography represents stream centerlines and off centerlines with greater than 30 hectare flow accumulation for the Northeast region. The purpose of this dataset is to improve the National Hydrography Dataset (NHD) for the Northeast region. The NHD is a national framework for assigning reach addresses to water-related entities, such as industrial discharges, drinking water supplies, fish habitat areas, wild and scenic rivers. Once linked by reach addresses, the upstream/downstream relationships of these water-related entities can be analyzed.