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I recently acquired a LiDAR data set that included a 1 meter DEM. I generated 1, 2 and 5m contour layers but I am seeing a lot of contours within water bodies. I suspect this is either caused by wave movement or in shallow areas where rocks/debris are present. I generated the contours using ArcGIS Desktop 10.3.1 3D Analyst.

What are my options for removing these contours? Should this elevation issue be addressed at the Lidar/DEM level? I have a shapefile that delimits the land from water that I could use for a break line.

  • That may be a solution. I'll see what happens. – rspencer38 Dec 15 '15 at 17:51
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One option is to use the water shapefile to erase the DEM; then generate the contours over a land-only DEM.

Actually, the erase tool will only work for vectors; the corresponding tool for raster is Extract by polygons (spatial analyst). Set the argument 'Extraction area' to 'outside'.

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A caveat is that pairs of coordinates in the 'Polygon' argument are required (instead of just selecting the shapefile from a dropdown).


Another option is to use Contour with barriers (spatial analyst) to generate contours based only in the outside area of the water polygons (the barriers).

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