HUC12 Boundaries of Indiana 2025

Source data found here: https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer Each drainage area is considered a Hydrologic Unit (HU) and is given a Hydrologic Unit Code (HUC) which serves as the unique identifier for the area. HUC 2s, 6s, 8s, 10s, & 12s, define the drainage Regions, Subregions, Basins, Subbasins, Watersheds and Subwatersheds, respectively, across the United States. Their boundaries are defined by hydrologic and topographic criteria that delineate an area of land upstream from a specific point on a river and are determined solely upon science based hydrologic principles, not favoring any administrative boundaries, special projects, or a particular program or agency. The Watershed Boundary Dataset is delineated and georeferenced to the USGS 1:24,000 scale topographic basemap. Hydrologic Units are delineated to nest in a multi-level, hierarchical drainage system with corresponding HUCs, so that as you move from small scale to large scale the HUC digits increase in increments of two. For example, the very largest HUCs have 2 digits, and thus are referred to as HUC 2s, and the very smallest HUCs have 12 digits, and thus are referred to as HUC 12s. Dataset Summary Phenomenon Mapped: Watersheds in the United States, as delineated by the Watershed Boundary Dataset (WBD) Geographic Extent: Contiguous United States, Alaska, Hawaii, Puerto Rico, Guam, US Virgin Islands, Northern Marianas Islands and American Samoa Projection: Web Mercator Update Frequency: Annual Visible Scale: Visible at all scales, however USGS recommends this dataset should not be used for scales of 1:24,000 or larger. Source: United States Geological Survey Publication Date: January 7, 2025 What can you do with this layer? This layer is suitable for both visualization and analysis acrossthe ArcGIS system. This layer can be combined with your data and other layers from the ArcGIS Living Atlas of the World in ArcGIS Online and ArcGIS Pro to create powerful web maps that can be used alone or in a story map or other application. Because this layer is part of the ArcGIS Living Atlas of the World it is easy to add to your map: In ArcGIS Online, you can add this layer to a map by selecting Add then Browse Living Atlas Layers. A window will open. Type "Watershed Boundary Dataset" in the search box and browse to the layer. Select the layer then click Add to Map. In ArcGIS Pro, open a map and select Add Data from the Map Tab. Select Data at the top of the drop down menu. The Add Data dialog box will open on the left side of the box, expand Portal if necessary, then select Living Atlas. Type "Watershed Boundary Dataset" in the search box, browse to the layer then click OK.源数据可访问于：https://hydro.nationalmap.gov/arcgis/rest/services/wbd/MapServer 每个汇水区均被定义为水文单元（Hydrologic Unit, HU），并分配有水文单元编码（Hydrologic Unit Code, HUC）作为该区域的唯一标识符。美国境内的HUC 2级、HUC 6级、HUC 8级、HUC 10级与HUC 12级编码，依次分别对应汇水区的大区、亚大区、流域盆地、亚流域盆地、流域与亚流域。 其边界基于水文与地形准则划定，用于勾绘河流特定点位上游的陆地区域，且完全依据基于科学的水文原理确定，不偏向任何行政边界、专项工程或特定项目与机构。本流域边界数据集（Watershed Boundary Dataset, WBD）基于美国地质调查局（USGS）1:24000比例尺地形底图进行勾绘与地理配准。 水文单元按照多级层级化汇水系统进行嵌套勾绘，并对应各自的HUC编码：当比例尺从大比例尺切换至小比例尺时，HUC编码的位数以2为增量递增。例如，级别最高的HUC编码为2位，即HUC 2级；级别最低的HUC编码为12位，即HUC 12级。 数据集概况 制图对象：基于流域边界数据集（WBD）勾绘的美国境内流域 地理覆盖范围：美国本土、阿拉斯加、夏威夷、波多黎各、关岛、美属维尔京群岛、北马里亚纳群岛和美属萨摩亚 投影坐标系：Web Mercator 更新频率：每年一次 可见比例尺：全比例尺下均可显示，但美国地质调查局（USGS）建议本数据集不适用于1:24000及更大比例尺的应用 数据来源：美国地质调查局 发布日期：2025年1月7日 该图层可实现的应用场景 本图层适用于ArcGIS生态系统内的可视化与分析工作。可将本图层与您自有数据及ArcGIS世界生活地图集（ArcGIS Living Atlas of the World）中的其他图层相结合，在ArcGIS Online与ArcGIS Pro中创建功能强大的Web地图，既可单独使用，也可嵌入故事地图或其他应用程序中。 由于本图层属于ArcGIS世界生活地图集的一部分，添加至地图的操作十分简便： 在ArcGIS Online中，依次选择「添加」→「浏览生活地图集图层」，将弹出窗口；在搜索框中输入"Watershed Boundary Dataset"，浏览至目标图层后选中该图层，再点击「添加至地图」即可完成添加。 在ArcGIS Pro中，打开地图后选择「地图」选项卡中的「添加数据」；在下拉菜单顶部选择「数据」，将弹出「添加数据」对话框，在左侧面板中展开「门户」（如有需要）并选择「生活地图集」；在搜索框中输入"Watershed Boundary Dataset"，浏览至目标图层后点击「确定」即可完成添加。