VT Data - VT Hydrography Dataset - cartographic extract polygons

(Link to Metadata) VHDCARTO is a simplified version of the local resolution Vermont Hydrography Dataset (VHD) that has been enriched with stream perenniality, e.g., "intermittent" vs. "perennial", as well as, Strahler stream order attribution for the single linear feature class only. The primary means of accessing this information cartographically is via the FCODE and STREAM_ORDER fields, respectively. See the Entity and Attribution Information section for details. NOTE! Perenniality data does not exist for stream reaches contained within, or intersected by, Essex or Caledonia counties, thus the FCODE "46000" in these areas. The absence of Soil SUrvey GeOgraphic (SSURGO) database information in these areas precluded the computation of perenniality. These areas will be processed at some future date. For information on the FCODE symbol for attribution or analysis see the following document https://www.usgs.gov/national-hydrography/national-hydrography-dataset (NHDFlowline). A two dimensional feature class for lakes, ponds and larger streams is also included in VHDCARTO. Both layers are derived from the latest National Hydrography Dataset (NHD) data. The NHD is a feature-based database that interconnects and uniquely identifies the stream segments or reaches that make up the nation's surface water drainage system. For information on the science behind computing perenniality attribution please refer to the following U.S. Geological Survey Scientific Investigative Report (SIR) # 2006-5217 - https://pubs.usgs.gov/sir/2006/5217/pdf/SIR2006-5217_report.pdf

(元数据链接) VHDCARTO 是本地分辨率佛蒙特州水文数据集（Vermont Hydrography Dataset, VHD）的简化版本，额外补充了溪流持续性（stream perenniality，即“间歇”与“常年”分类）属性，同时仅针对单一线性要素类添加了斯特拉勒河流级序（Strahler stream order）属性赋值。该数据集的制图属性主要通过FCODE与STREAM_ORDER两个字段分别获取。详细信息请参见“要素与属性信息”章节。
注意！埃塞克斯县（Essex）或喀里多尼亚县（Caledonia）范围内及与之相交的河段暂无溪流持续性数据，因此这些区域的FCODE值为“46000”。由于该区域缺少土壤调查地理数据库（Soil Survey GeOgraphic, SSURGO）的相关数据，无法完成溪流持续性属性的计算，后续将对这些区域开展补处理工作。
如需了解用于属性赋值或分析的FCODE符号相关信息，请参阅以下文档：https://www.usgs.gov/national-hydrography/national-hydrography-dataset (NHDFlowline)
VHDCARTO 还包含湖泊、池塘及大型溪流的二维要素类。所有图层均源自最新版国家水文数据集（National Hydrography Dataset, NHD）。NHD是一套基于要素的数据库，可实现构成美国地表排水系统的各河段的关联与唯一标识。
如需了解溪流持续性属性计算的相关科学原理，请参阅美国地质调查局科学调查报告（Scientific Investigative Report, SIR）#2006-5217：https://pubs.usgs.gov/sir/2006/5217/pdf/SIR2006-5217_report.pdf