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Import a LIDAR GeoTIFF DEM into Civil 3D (Australia)

Last updated July 28, 2026

Free LIDAR now covers most of Australia, and a GeoTIFF elevation model will build you a surface in Civil 3D in about two minutes — once you get the coordinate system right. Getting it wrong is what costs the afternoon, and it is the part nobody mentions.

This covers two imports: a LIDAR digital elevation model as a .tif, and boundary lines as an ESRI shapefile. The video walks through both.

Where the free data comes from

  • Elevation — ELVIS, the Elevation and Depth Foundation Spatial Data portal. Draw a box over your site, pick the LIDAR-derived DEM, and it emails you a download link. The file arrives as a GeoTIFF.
  • Boundaries and cadastre — each state runs its own. Tasmania’s is LISTmap, which exports ESRI shapefiles. The other states have equivalents.

Both are free and both are public. What you get is survey-grade enough for feasibility, concept design and volumes; it is not a substitute for a real survey when you are setting out.

Set the coordinate system first

Do this before you import anything, not after.

Australian spatial data is projected on the Map Grid of Australia, in one of the MGA zones, and against one of two datums: GDA94 for older data and GDA2020 for anything recent. The two are roughly 1.8 metres apart on the ground. That is small enough that a surface will still look plausible, and large enough to matter on a building.

So check what the download actually is — the portals state the datum and zone with the file — and set the drawing to match in the drawing settings before you import. If your surface lands in the ocean, or a kilometre from the boundary you imported five minutes ago, this is why.

The other consequence is worth knowing: if the DEM and the shapefile are on different datums, Civil 3D will happily place them both, and they will not line up. Bring everything onto one datum before you draw anything.

Importing the LIDAR DEM

  1. Set the drawing’s coordinate system to the datum and MGA zone of the data.
  2. In Toolspace, on the Prospector tab, right-click Surfaces and create a new TIN surface. Give it a name you will recognise later — the file name of the tile is a good one.
  3. Expand the new surface, then its Definition, and add the .tif under DEM Files.
  4. Confirm the coordinate system in the dialog that appears, and let it build.

A LIDAR tile can be very dense. If the drawing becomes unresponsive, that is the point at which to think about the surface’s display style and about trimming the surface to the area you actually need rather than carrying the whole tile.

Importing the boundary shapefile

  1. Type MAPIMPORT.
  2. Set the file type to ESRI Shapefile and pick the .shp.
  3. In the import dialog, assign the coordinate system of the data if it is not already detected, and decide what to do with the attributes — you can bring the parcel data in as object data rather than throwing it away.
  4. Import, then check the result sits over the surface where you expect.

A shapefile is not one file. It is a set — .shp, .shx, .dbf and usually a .prj — and they all have to stay together in the same folder with the same base name. The .prj is the one that carries the coordinate system, so if it went missing in a zip somewhere you will be assigning that by hand.

Checks worth doing before you rely on it

  • Spot-check a level. Pick a point you know — a kerb, a floor level from an existing drawing — and compare. LIDAR is a surface model of what the scanner saw, which is not always the ground.
  • Look at the vegetation. A “bare earth” DEM has had the vegetation classified out, but never perfectly. Dense scrub reads high.
  • Check the date. Elevation data is a snapshot. If the site has been cut, filled or built on since the flight, the model is history rather than ground.
  • Check the vertical datum. Heights are usually to AHD; confirm rather than assume, particularly if you are tying into a drainage design.

References