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

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'.

enter image description here

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).

enter image description here

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.