NHDPlusV2.1 Catchments

Open the Data Source: https://gis.chesapeakebay.net/ags/rest/services/Boundaries/NHDPlusV2_Catchment/MapServer/0 This layer provides the 1:100,000 NHDPlusV2.1 catchments within Chesapeake Bay watershed, including all catchments that intersect with the Chesapeake Bay watershed boundary. NHDPlus is an integrated suite of application-ready geospatial data products, incorporating many of the best features of the National Hydrography Dataset (NHD), the National Elevation Dataset (NED) and the National Watershed Boundary Dataset (WBD). NHDPlus, based on the medium resolution NHD (1:100,000-scale), includes the stream network and improved linear networking, feature naming and value added attributes (VAA). NHDPlus also includes elevation-derived catchments. NHDPlusV2 is significantly improved from and supersedes NHDPlusV1.打开数据源：https://gis.chesapeakebay.net/ags/rest/services/Boundaries/NHDPlusV2_Catchment/MapServer/0 该图层包含切萨皮克湾流域范围内的1:10万比例尺NHDPlusV2.1集水区，涵盖所有与切萨皮克湾流域边界相交的集水区。 NHDPlus是一套集成化、可直接应用的地理空间数据产品套件，融合了国家水文数据集（National Hydrography Dataset, NHD）、国家高程数据集（National Elevation Dataset, NED）与国家流域边界数据集（National Watershed Boundary Dataset, WBD）的诸多优质特性。 该套件以中等比例尺（1:10万）的国家水文数据集（NHD）为基础，包含河网、优化的线性网络结构、要素命名信息以及增值属性（value added attributes, VAA）。此外，NHDPlus还涵盖基于高程数据提取的集水区。 NHDPlusV2相较NHDPlusV1实现了大幅改进，并已取代后者。