Generating seamless contours across tiles from TIN/LiDAR data?

Question

I have both TINs and LiDAR data for an entire county, divided into a grid of multiple tiles. I want to generate contours from this data at 2 foot intervals, using ArcGIS 10.5.

I decided to do this by first generating an elevation raster using TIN to Raster, and then running the Contour tool to create contours from the raster.

The problem is that the resulting contours have a gap where the tiles meet. The width of the gap is equal to the cell size I specify when creating the raster.

How can I eliminate this gap and get contours that are seamless across tiles?

Would it be better to start with the LIDAR data instead, or would I still encounter a similar problem?

Answer 1

Would it be better to start with the LiDAR data instead?

Yes, it would. Here is the processing workflow:

• Create a LAS Dataset *. This is the standard way to import multiple LiDAR (.las) files in ArcGIS.
• Filter the point cloud by class code = 2 (ground points) by making a LAS Dataset Layer.

From here, there are at least two options:

1. As pointed out by Jae, directly generate contours from filtered Las Dataset Layer with Surface Contour tool **.
2. Or generate a DEM with the LAS Dataset to Raster tool *. Then, create contours from the DEM raster ***.

Choose option one if you are sure the intermediate output raster will not be needed in further/parallel tasks.

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