Stream_flowpath_24K_HydroEdge

HydroEdges represent the blue lines (streams) on a traditional topographic map, plus linear features that flow through and connect waterbodies such as lakes, 2D rivers, and wetlands to the stream network. HydroEdge was originally populated using the high resolution National Hydrography Dataset (NHD), in particular the NHDFlowline feature class, but has subsequently been extensively updated by SJRWMD staff. * Types of HydroEdges are defined by the field NHDFType: StreamRiver, CanalDitch, ArtificialPath, Connector, Pipeline, and Coastline. ArtificialPath and Connector are features whose purpose is to continue the connectivity of the geometric network through waterbody and river polygons - places where the blue lines on a traditional topographic map disappear. * HydroEdge is part of the SJRWMD Water Resources Geodatabase (WRGDB), which is based on the ArcHydro data model. It is one of the two core layers that define the geometric network in the WRGDB. However, it can also be used independently as a simple 1:24,000 stream dataset, by only drawing StreamRiver and CanalDitch features. * The HydroEdge layer also contains unique IDs for each feature. HydroCode is the SJRWMD HydroEdge ID. NHDComID is the original ID from the NHD, however, as features are edited, the integrity of NHDComID may be compromised, and we do not guarantee that the value is correct. * Date of last update: December 2013.HydroEdges 指代传统地形图上的蓝色线条（溪流），以及流经湖泊、二维河流、湿地等水体并将其连接至河网的线性要素。HydroEdge 最初基于高分辨率国家水文数据集（National Hydrography Dataset，NHD）构建，尤其使用了其中的 NHDFlowline 要素类，后续由 SJRWMD 工作人员进行了大规模更新。 * HydroEdge 的类型由字段 NHDFType 定义，包括 StreamRiver、CanalDitch、ArtificialPath、Connector、Pipeline 及 Coastline。其中 ArtificialPath 与 Connector 要素用于在水体和河流多边形区域（即传统地形图上蓝色线条消失的区域）维持几何网络的连通性。 * HydroEdge 隶属于 SJRWMD 水资源地理数据库（Water Resources Geodatabase，WRGDB），该数据库基于 ArcHydro 数据模型构建。它是 WRGDB 中定义几何网络的两大核心图层之一。若仅绘制 StreamRiver 与 CanalDitch 要素，该数据集也可作为独立的 1:24000 比例尺溪流数据集单独使用。 * HydroEdge 图层包含每个要素的唯一标识符：HydroCode 为 SJRWMD 专属的 HydroEdge 标识符；NHDComID 为 NHD 提供的原始标识符，但由于要素会被编辑，NHDComID 的完整性可能受损，本数据集不保证该字段值的准确性。 最后更新日期：2013年12月。