topic Re: Determine Floodplain: Based on known flood level in 3D Questions https://community.esri.com/t5/3d-questions/determine-floodplain-based-on-known-flood-level/m-p/50525#M355 <HTML><HEAD></HEAD><BODY><SPAN>Duplicate thread.</SPAN><BR /><BR /><SPAN>See answer on Spatial Analyst forum:</SPAN><BR /><A href="http://forums.arcgis.com/threads/96796-Determine-Floodplain-Based-on-known-flood-level">http://forums.arcgis.com/threads/96796-Determine-Floodplain-Based-on-known-flood-level</A><BR /><BR /><SPAN>Xander</SPAN></BODY></HTML> Thu, 14 Nov 2013 11:04:05 GMT XanderBakker 2013-11-14T11:04:05Z Determine Floodplain: Based on known flood level https://community.esri.com/t5/3d-questions/determine-floodplain-based-on-known-flood-level/m-p/50524#M354 <HTML><HEAD></HEAD><BODY><SPAN>I have delineated a river centreline and interpolated the Z values from a DEM (SRTM 90m) to generate a 3D polyline that represents the river centreline. I have then adjusted the Z values within the 3D river centreline and increased it by 20m and 40m respectively. I've tried to use Visibility Analysis tool to try to generate the floodplain, but the results aren't great even after adjusting the vertical, horizontal and radius parameters. Any alternative would appreciated. </SPAN><BR /><BR /><SPAN>So as explained, I'm trying to delineate the expected inundated surface areas coarsely from the river centreline, based on an adjusted Z value, then trying to determine the horizontal impact area of the DEM that is covered by water.</SPAN><BR /><BR /><SPAN>Regards</SPAN></BODY></HTML> Wed, 13 Nov 2013 18:44:14 GMT https://community.esri.com/t5/3d-questions/determine-floodplain-based-on-known-flood-level/m-p/50524#M354 PeterWilson 2013-11-13T18:44:14Z Re: Determine Floodplain: Based on known flood level https://community.esri.com/t5/3d-questions/determine-floodplain-based-on-known-flood-level/m-p/50525#M355 <HTML><HEAD></HEAD><BODY><SPAN>Duplicate thread.</SPAN><BR /><BR /><SPAN>See answer on Spatial Analyst forum:</SPAN><BR /><A href="http://forums.arcgis.com/threads/96796-Determine-Floodplain-Based-on-known-flood-level">http://forums.arcgis.com/threads/96796-Determine-Floodplain-Based-on-known-flood-level</A><BR /><BR /><SPAN>Xander</SPAN></BODY></HTML> Thu, 14 Nov 2013 11:04:05 GMT https://community.esri.com/t5/3d-questions/determine-floodplain-based-on-known-flood-level/m-p/50525#M355 XanderBakker 2013-11-14T11:04:05Z