FEMA Floodways in King County

For more information about this layer please see the GIS Data Catalog. A compilation of best available floodway boundaries. A floodway is the channel of a stream plus any adjacent floodplain area that must be kept free of encroachment so that the 1 percent annual chance flood can be carried without substantial increases in flood heights.

如需了解此图层的更多信息，请参阅地理信息系统数据目录（GIS Data Catalog）。本数据集汇集了现有最优的行洪道边界数据。行洪道系指河道及相邻漫滩区域，需确保该区域不受侵占，以使年发生概率1%的洪水能够顺利通过且洪水位不会出现显著升高。