Areas of uncertainty for flood inundation extents at gage 14211500, Johnson Creek near Sycamore, Oregon (sycor_breach.shp)

​The basis for these features is U.S. Geological Survey Scientific Investigations Report 2017-5024 Flood Inundation Mapping Data for Johnson Creek near Sycamore, Oregon. The domain of the HEC-RAS hydraulic model is a 12.9-mile reach of Johnson Creek from just upstream of SE 174th Avenue in Portland, Oregon, to its confluence with the Willamette River. Some of the hydraulics used in the model were taken from Federal Emergency Management Agency, 2010, Flood Insurance Study, City of Portland, Oregon, Multnomah, Clackamas, and Washington Counties, Volume 1 of 3, November 26, 2010. The Digital Elevation Model (DEM) utilized for the project was developed from lidar data flown in 2015 and provided by the Oregon Department of Geology and Mineral [...]