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The 5 Best Free Sources of Digital Elevation Model (DEM) Data in Australia

Published on Dec 7, 2024

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Looking to analyze terrain for environmental studies, engineering projects, or research? This guide will walk you through the best free Digital Elevation Model (DEM) sources available to Australians.

Summary

Understanding Digital Elevation Data

A Digital Elevation Model represents the Earth’s terrain as a three-dimensional digital grid known as a raster GIS layer. Each cell in the grid stores precise elevation information. These heights are measured against what’s known as a vertical datum—a standardized reference point for zero elevation, typically based on mean sea level. These models are fundamental tools for understanding terrain and topography.

Many techniques are used to create digital elevation models, each with its own strengths and applications. Drone photogrammetry excels at capturing detailed data for small project areas. Aerial LiDAR provides precise elevation measurements and can penetrate vegetation, making it ideal for both Digital Surface Models (DSMs) that include buildings and vegetation, and Digital Terrain Models (DTMs) that represent bare earth. Satellite-derived elevation data offers consistent coverage over vast areas, perfect for regional or continental-scale analysis.

Types of Digital Elevation Models

Digital Surface Models (DSM)

DSMs capture the Earth’s surface including all objects on it - buildings, vegetation, and other human-made structures. They’re particularly valuable for urban planning, aviation studies, and vegetation management. These models represent the first surface that would be hit by a raindrop, whether that’s a tree canopy, building roof, or the ground.

Digital Terrain Models (DTM)

DTMs represent the bare earth surface with all vegetation and built structures removed. This makes them ideal for flood modeling, watershed analysis, and infrastructure planning. They show the ground level that would be exposed if all buildings and vegetation were removed.

Digital Elevation Models (DEM)

DEM is often used as an umbrella term encompassing both DSMs and DTMs. At larger scales where the distinction between surface features and bare earth becomes less significant (such as with 30m resolution data), the term DEM is commonly used. The choice between these models depends on your project’s requirements - from high-precision local surveys to broad regional studies.

Common Applications

Terrain Analysis and Resource Assessment

DEMs help analysts identify geological features like faults, folds, and lineaments in the terrain. By analyzing surface expressions and drainage patterns, field teams can better understand an area’s structural geology and plan their investigation programs more efficiently.

Site Planning and Development

When developing new projects in complex terrain, DEMs are crucial for optimizing site layouts, calculating earthwork volumes, and planning access roads. The elevation data helps engineers determine the most efficient construction approaches while ensuring proper drainage and minimal environmental impact.

Slope Stability Monitoring

Large infrastructure projects use repeated DEM surveys to track subtle changes in ground movement and detect potential stability issues before they occur. This ongoing monitoring is essential for maintaining site safety and preventing costly disruptions that could result from ground movement or landslides.

What’s Available in Australia

If you’re searching for free digital elevation maps in Australia, it’s important to understand what’s available.

Australia benefits from excellent access to open-source elevation data, with multiple options available to suit different project needs. Nation-wide coverage is readily available through 30-meter resolution DEMs, providing a solid foundation for regional analysis.

Higher resolution models, typically ranging from 1 to 5 meters, are concentrated around urban centers and coastal regions where detailed terrain information is crucial. Several state governments have taken the initiative to release comprehensive statewide elevation models, further expanding access to quality terrain data for specific regions.

Detailed Source Overview

1. ELVIS - Elevation Information System

ELVIS is Australia’s national elevation data portal, managed by Geoscience Australia. It’s the perfect starting point for any terrain analysis project.

Key Features:

  • User-friendly web interface for data discovery
  • Multiple resolution options (1m to 30m)
  • Direct download capabilities
  • Extensive metadata and quality information
  • Regular updates for priority areas

2. Digital Earth Australia

Digital Earth Australia is a government platform that transforms raw satellite and elevation data into ready-to-use information. It provides powerful tools for understanding Australia’s changing landscape.

Key Features:

  • Time-series elevation data
  • Advanced analysis tools
  • Integration with satellite imagery
  • Focus on environmental monitoring
  • Regular data updates

3. State-Specific Resources

QSpatial (Queensland)

Queensland’s open data portal offers comprehensive elevation datasets through QSpatial, providing high-quality DEMs particularly for coastal and urban regions.

Key Features:

  • 5m resolution LiDAR-derived DEMs
  • Excellent coastal coverage
  • Regular updates for development areas
  • Integration with other spatial datasets

NSW Spatial Services

The NSW Spatial Services portal delivers authoritative elevation data for New South Wales, with particular emphasis on urban and development areas.

Key Features:

  • High-resolution elevation data
  • Comprehensive urban coverage
  • Advanced terrain modeling
  • Detailed metadata

VicMap (Victoria)

VicMap provides Victoria’s foundational elevation dataset, offering consistent coverage across the entire state through their spatial data infrastructure.

Key Features:

  • State-wide 10m resolution DEM
  • Derived from various data sources including LiDAR
  • Regular updates and quality improvements
  • Seamless coverage across Victoria

4. Global Digital Elevation Models

SRTM (Shuttle Radar Topography Mission)

The SRTM dataset, collected by NASA in 2000, remains one of the most widely used global elevation datasets due to its consistent quality and complete coverage.

Key Features:

  • 30m resolution globally
  • Well-validated accuracy
  • Complete coverage of Australia
  • Suitable for regional analysis

AW3D30

ALOS World 3D 30m (AW3D30) is JAXA’s global elevation dataset, collected between 2006-2011, offering improved accuracy over SRTM particularly in areas of steep terrain.

Key Features:

  • 30m resolution global DEM
  • Updated more recently than SRTM
  • Better handling of void areas
  • Improved vertical accuracy

Copernicus DEM

The Copernicus DEM is a recent addition to global elevation datasets, providing high-quality terrain data through the European Union’s Earth observation program.

Key Features:

  • Global coverage at 30m resolution (GLO-30)
  • Higher resolution (10m) available over Europe only
  • Based on TerraSAR-X and TanDEM-X data (2011-2015)
  • High absolute vertical accuracy (2-4m)
  • Freely available through the Copernicus Data Space Ecosystem

Conclusion

Australia offers excellent free Digital Elevation Model resources suitable for various applications. Whether you’re conducting environmental research, planning infrastructure, or analyzing watersheds, these platforms provide the elevation data you need. Start with the platform that best matches your technical requirements and project scope.

Need satellite imagery to complement your elevation data? Check out our comprehensive guide to 10 Free Sources of Satellite Imagery in Australia for the best available options.