Stream Type

For more information about this layer please see the GIS Data Catalog. Stream Type is a watercourse layer that identifies the regulatory stream type per the County’s definitions in the Critical Areas Ordinance. The baseline data for the physical stream location comes from the Coho Intrinsic Potential stream layer, which was based on the county’s ‘watercourse’ layer circa 2020. The 4 types of stream are: S -Shoreline of the state, F - Fish bearing or has fish habitat, and N - Non-fish bearing, and O- Other. Currently many smaller streams do not have enough data to be classified as a particular stream type without a field survey. If the classification is unknown, the classification is left blank. Shoreline jurisdiction is defined by Washington Department of Ecology and the County’s Shoreline Master Plan. Fish observations, fish use based on physical channel measurements, and presumed fish use data come from multiple sources, including King County, WRIA fish distribution maps, Wild Fish Conservancy, and the Statewide Washington Fish Wide Distribution (SWIFD) datasets. Stream type attribution is based on a hierarchical scheme whereby shoreline and fish observations are populated first, followed by F type designations based on physical channel measurements versus documented fish observations and finally, presumed use. The Stream Type field is not fish species specific, but there are separate fields for the species listed on the Endangered Species Act list- Chinook salmon, steelhead trout, and bull trout or dolly varden. These fish species fields are populated based on documented observations, and a blank value does not necessarily indicate that the species would not use the stream reach.如需了解该图层的更多信息，请参阅地理信息系统（Geographic Information System, GIS）数据目录。水系类型（Stream Type）图层属于河道图层，用于根据本县《临界区域条例》中的定义，标识合规河道类型。河道实体位置的基准数据来自银鲑固有潜力水系图层（Coho Intrinsic Potential stream layer），该图层基于本县2020年左右的“河道”图层制作。该数据集共包含四类河道：S代表州级岸线，F代表有鱼类生存或具备鱼类栖息地，N代表无鱼类生存，O代表其他类型。目前，多数小型河道缺乏足够数据，无法在未开展野外调查的情况下确定其河道类型。若无法确定分类结果，则该字段留空。岸线管辖权由华盛顿州生态部（Washington Department of Ecology）及本县《岸线总体规划》界定。鱼类观测记录、基于河道实体测量的鱼类利用数据，以及推测性鱼类利用数据来源于多个渠道，包括金县（King County）、WRIA鱼类分布图、野生鱼类保护协会（Wild Fish Conservancy），以及全州华盛顿鱼类分布（Statewide Washington Fish Wide Distribution, SWIFD）数据集。水系类型属性赋值采用层级化逻辑：首先填充岸线与鱼类观测数据，其次基于河道实体测量结果与已记录的鱼类观测信息赋予F类标识，最后依据推测性利用情况完成赋值。水系类型字段并不针对特定鱼类，但针对《濒危物种法案》（Endangered Species Act）所列物种设有单独字段：奇努克鲑（Chinook salmon）、钢头鳟（steelhead trout），以及公牛鳟或花鳟（bull trout or dolly varden）。上述鱼类物种字段依据已记录的观测结果填充，字段留空并不代表该物种不会利用该河段。