Active Channel WRIA 46 Entiat

Active channel hydrography (referred to as open channel or bank-to-bank polygon in the State and Tribal Riparian Monitoring and Adaptive Management Recommendations) is defined as an approximation of the active channel width of a stream determined using remote sensing methods, e.g. lidar, and is inclusive of gravel and cobble bars and the wetted portion of the stream. The active channel is analogous to the “bankfull channel” (Leopold and Maddock 1953, Leopold et al 1964, Williams 1978) or the ordinary high-water mark line (WAC 220-660-030(111), where the presence and action of waters are “so common and usual, and so long continued in ordinary years as to mark upon the soil or vegetation a character distinct from the abutting upland,” and along freshwater where this line cannot the delineated the ordinary high water line is the elevation of the mean annual flood for every three years. The intent for these data is to identify the edge of the stream riparian, i.e., where woody vegetation begins, for riparian and ecosystem monitoring. Methods document is available for download at https://wa-psp.maps.arcgis.com/sharing/rest/content/items/ef23b0e8c4ca48feac8c46c0f6d697b1/data Scripts and the spatial data framework to generate active channels are available at the Puget Sound Partnership Spatial Hub https://data-wa-psp.hub.arcgis.com/content/a3b36a7ba14e4670851503d7eb7f0e4e/about活动河道水文要素（Active channel hydrography）——在《州与部落河岸监测与自适应管理建议》中亦被称为明渠或岸至岸多边形——指通过遥感手段（如激光雷达（LiDAR））测算得到的河道活动宽度近似值，涵盖砾石滩、鹅卵石滩以及河道的过水湿地区域。该活动河道概念与“满岸河道”（Leopold与Maddock，1953；Leopold等，1964；Williams，1978）或“普通高水位线”（WAC 220-660-030(111)）相近，其中普通高水位线的定义为“在常规年份中，水体长期频繁出现并发挥作用，从而在土壤或植被上形成与毗邻高地截然不同的特征标识”；若在淡水区域无法划定该线，则普通高水位线取每三年一遇的年平均洪水高程。本数据集的研制目的是为河岸与生态系统监测工作明确河道河岸带的边界——即木本植被起始生长的区域。相关方法文档可通过以下链接下载：https://wa-psp.maps.arcgis.com/sharing/rest/content/items/ef23b0e8c4ca48feac8c46c0f6d697b1/data。用于生成活动河道的脚本与空间数据框架，可在普吉特海湾合作组织空间枢纽（Puget Sound Partnership Spatial Hub）获取，链接为：https://data-wa-psp.hub.arcgis.com/content/a3b36a7ba14e4670851503d7eb7f0e4e/about