Flood mapping

[yoganandhanram]

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

[MattMead]

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.

[AlexUber]

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