topic Re: Flood mapping in 3D Questions

Flood mapping

yoganandhanram — Tue, 22 Mar 2011 10:11:35 GMT

i need to create DEM with the Mean sea level And assess how much will be inundated if 5cm rise of sealevel using Arc GIS 9.3

Re: Flood mapping

MattMead — Thu, 24 Mar 2011 15:04:14 GMT

You are basically looking to do what this guy is doing: http://forums.arcgis.com/threads/20429-Example-Flooding-Scenario

If you know your water surface elevations, just create polylines with the elevations attributed to them. Convert these cross sections to TIN's using 3danalyst->create TIN from feature.

Tin difference (comparing your water surface to your terrain TIN) will give you a polygon with the flood extents. If you want the depths, convert the terrain and water surface TINs to rasters and use Spatial Analyst to subtract your terrain from the water.

Re: Flood mapping

AlexUber — Tue, 09 Aug 2011 17:15:31 GMT

Hello, I noticed this thread and have a question.

I've recently converted to arc 10 and I have a lidar data that I'm trying to do simple inundation models. With arc 9.3 i was able to do this by 'converting' e00 files in Arc catalog (not sur what I converted them to however). Anyway, I could then use those files to show areas of floodplain inundation using the elevation exclusion function and the color ramp display.

Anyway, I've since then gotten a new lidar data set and with arc 10 I'm not able to duplicate these images. Any thoughts? THanks (and I hope this makes sense enought for you to follow)

Alex in Vanc WA