In geospatial projects, accuracy is key. Whether for 5G planning, flood risk assessment, or urban simulations, reliable elevation data is essential. Yet, many professionals confuse DTM (Digital Terrain Model), DSM (Digital Surface Model), and HDTM (Hydro-Enforced Digital Terrain Model).
Each serves a distinct purpose, and choosing the wrong one can impact project outcomes. This article explains their differences, highlights use cases, and helps you select the right model for your needs
A Digital Terrain Model (DTM) represents the bare-earth surface of the Earth, stripped of vegetation, buildings, and infrastructure. It provides a clean elevation dataset that focuses exclusively on the ground surface.
DTMs are usually derived from Digital Surface Models (DSM) by removing all above-ground objects using specialized algorithms and manual editing. LuxCarta’s DTM, for instance, leverages tri-stereo satellite imagery to deliver high-resolution, object-free elevation data.
Key use cases of DTM:
- RF & 5G network planning: modeling signal propagation without interference from obstacles.
- Flood risk assessment: simulating water flow across unobstructed terrain.
- Mobility studies: analyzing vehicle or pedestrian movement on realistic ground surfaces.
- Infrastructure design: creating reliable bases for construction or environmental projects.
👉 Learn more about LuxCarta’s DTM here
Unlike a DTM, a Digital Surface Model (DSM) captures everything visible from above: terrain, buildings, vegetation, and infrastructure. In short, DSMs represent the Earth’s surface “as-is,” including all obstacles and objects.
LuxCarta’s DSM is generated from tri-stereo satellite imagery, which reduces occlusions (blind spots) and ensures high completeness. Water surfaces such as lakes and large rivers are flattened for consistency, and outputs are delivered in ready-to-use formats like GeoTIFF.
Key use cases of DSM:
- Urban planning & smart cities: accurate 3D models of built environments.
- Telecom planning: modeling obstacles that affect signal paths and line-of-sight analysis.
- Simulation & visualization: realistic landscape modeling for training, VR, and defense.
- Energy projects: siting solar farms, wind turbines, or power lines with surface features in mind.
👉 Learn more about LuxCarta’s DSM here
The Hydro-Enforced Digital Terrain Model (HDTM) is a specialized terrain model optimized for hydrologic and hydraulic applications. While a standard DTM provides a bare-earth surface, it may still include artifacts that disrupt natural water flow, such as bridges or road embankments.
LuxCarta’s HDTM corrects these limitations by enforcing hydrologic flow paths. Rivers, streams, and drainage networks are represented accurately, ensuring that water flows realistically across the terrain. This makes HDTM an invaluable dataset for applications where water modeling and climate resilience are critical.
Key use cases of HDTM:
- Flood risk assessment: modeling floods with hydrologically corrected elevation data.
- Watershed and drainage modeling: simulating how water moves across landscapes.
- Infrastructure planning: ensuring new developments consider water flow and drainage.
- Climate resilience studies: supporting governments and insurers in risk analysis.
👉 Learn more about LuxCarta’s HDTM here
Choosing the right elevation model depends on your project’s needs:
Choose DTM if you need a clean ground surface without above-ground features.
Choose DSM if you require the complete surface including obstacles.
Choose HDTM if your project involves water modeling, flood risk, or hydrologic analysis.
Working with an experienced provider like LuxCarta ensures not only that you get the right model, but also that it is produced consistently and delivered in formats compatible with your workflows.
DTM, DSM, and HDTM each provide unique insights into the Earth’s surface. While they may sound similar, their differences are crucial depending on your application, from telecom planning to flood risk assessment.
At LuxCarta, we provide globally consistent, high-accuracy elevation datasets that help planners, engineers, and analysts make informed decisions with confidence.
👉 Talk to our experts today to find out which model best suits your project or explore our elevation models for more technical details.