Florida Hydrography Dataset (FHD) (Formerly NHD) - Areas (24k)

The Florida Hydrography Dataset (FHD) is a feature-based database that interconnects and uniquely identifies the stream segments or reaches that make up the state's surface water drainage system. The FHD is based on the original National Hydrography Dataset (NHD) data was originally developed at 1:100,000-scale and exists at that scale for the whole country. This high-resolution FHD, generally developed at 1:5,000 scale, adds detail to the original 1:100,000-scale NHD. (Data for Alaska, Puerto Rico and the Virgin Islands was developed at high-resolution, not 1:100,000 scale.) The FHD contains reach codes for networked features, flow direction, names, and centerline representations for areal water bodies. Reaches are also defined on waterbodies and the approximate shorelines of the Great Lakes, the Atlantic and Pacific Oceans and the Gulf of Mexico. The FHD also incorporates the National Spatial Data Infrastructure framework criteria established by the Federal Geographic Data Committee.佛罗里达水系数据集（Florida Hydrography Dataset，简称FHD）是一款基于要素的数据库，用于关联并唯一标识构成该州地表排水系统的河流段或河段。该数据集基于原始的国家水系数据集（National Hydrography Dataset，简称NHD）构建，后者最初以1:100000比例尺开发，并在全美范围内统一采用该比例尺标准。这款高分辨率版本的FHD通常以1:5000比例尺开发，为原始1:100000比例尺的NHD补充了更多细节信息。（阿拉斯加、波多黎各和美属维尔京群岛的相关数据采用高分辨率标准开发，未采用1:100000比例尺。）FHD包含网络化要素的河段编码、水流方向、水体名称，以及面状水体的中心线表达形式。该数据集还针对五大湖、大西洋、太平洋以及墨西哥湾的水体及近似岸线定义了河段。此外，FHD还遵循由联邦地理数据委员会（Federal Geographic Data Committee）制定的国家空间数据基础设施框架标准。