We’re living in a time where the land beneath our feet is being mapped more accurately than ever. From construction sites in the suburbs to mining operations in remote WA, understanding the shape of the ground is crucial. That’s where Digital Elevation Models (DEMs) come in.
They might not get the spotlight like AI or drones. But DEMs are quietly powering everything from flood risk analysis to city planning. And with Australia’s sheer size and geographic extremes, having accurate elevation data has never been more important.
What is a DEM?
DEM stands for Digital Elevation Model. It is a digital representation of ground surface topography. DEM captures the highs and lows of the land using a grid of elevation points. Think of it like a virtual blanket laid over the earth. Every point on that blanket knows its exact height above sea level.
You can zoom in and analyse terrain at almost any scale. It could be local, regional, or national. The data feeds into 3D models, simulations, and visualisations that help people make informed decisions across a wide range of industries.
How Are DEMs Created?
DEM production has come a long way from traditional survey methods. These days, aerial technology, particularly drones, plays a big role.
1. LiDAR (Light Detection and Ranging)
LiDAR sensors emit laser pulses that reflect off surfaces and return to the sensor. The time it takes for each pulse to bounce back is used to calculate distances with pinpoint accuracy.
Drones equipped with LiDAR can map vast, complex landscapes — even through vegetation. That’s a major advantage in Australia, where bushland, uneven terrain and remote areas are common.
2. Photogrammetry
Photogrammetry involves capturing a series of overlapping photographs from the air. Software processes these images, identifies common points between them, and reconstructs 3D models of the land.
It’s ideal for smaller sites, and although not quite as precise as LiDAR in densely vegetated or shadowed areas, it’s cost-effective and quick.
3. Satellite and Radar Data
DEM data is also gathered via satellite, especially for broad regional studies. It’s not as detailed, but for high-level planning or environmental monitoring, it does the job.
DTM, DSM, or DEM? What’s the Difference?
Let’s clear up the terminology:
- DEM (Digital Elevation Model) is often used as a general term.
- DTM (Digital Terrain Model) represents the bare ground — no trees, buildings, or man-made features.
- DSM (Digital Surface Model) includes everything sitting on the land’s surface — trees, buildings, and even vehicles.
Different models suit different purposes. For flood modelling, a DTM gives the most accurate picture of water flow. For urban planning or visualisation, a DSM provides valuable detail.
Where DEMs Make a Real Difference in Australia
1. Urban Planning and Development
Before building starts, planners need to understand the terrain. Is the site sloped? Prone to pooling water? How will roads or structures affect drainage?
DEMs provide clear answers. They reduce guesswork, help with grading design, and speed up project approvals. Local councils and developers often rely on this data during early planning stages.
2. Flood Risk Modelling
Flood events are increasing in both frequency and severity across Australia. DEMs are crucial in modelling how water moves across a landscape. They inform everything from where to place levees, to how to plan evacuation routes.
Higher resolution means more accurate simulations — and better-prepared communities.
3. Mining and Resource Exploration
Australia’s mining operations are built on solid data. DEMs support site planning, safety assessments, haul road design, and environmental management. Since many mine sites are remote, drone-based DEMs offer a safe and fast way to keep track of surface changes.
4. Renewable Energy Projects
Whether it’s wind turbines or solar farms, terrain impacts energy efficiency. DEMs are used to assess elevation, slope, and exposure — key factors in designing viable renewable energy projects.
5. Infrastructure Monitoring
From roads and railways to transmission lines and pipelines, DEMs help detect ground movement, plan maintenance, and model infrastructure performance under different environmental conditions.
Drones Are Changing the Game
Before drones, getting high-quality elevation data was slow and expensive. Traditional surveys took weeks, required large crews, and weren’t always feasible in tricky locations.
Now, drones equipped with LiDAR or high-resolution cameras can scan a site in a matter of hours. They’re safe, fast, and highly accurate — and they don’t disrupt active work sites.
Companies like Two70° are leading the way in this space. They deliver tailored drone survey services across Australia, helping clients in construction, energy, mining and beyond. Their drone-captured DEMs offer a smarter way to understand terrain, without ever having to put boots on the ground.
What Does a DEM Look Like?
Visualising a DEM can be as simple or as complex as you like. At its core, it’s a grayscale grid. Lighter shades mean higher elevation; darker shades mean lower ground.
But in practical use, DEMs are often layered with colour-coded elevation bands, slope shading, or 3D fly-throughs — especially when used for presentations or stakeholder engagement.
With the right software, users can:
- Generate contour lines
- Run hydrological analysis
- Create 3D terrain models
- Simulate line of sight or solar exposure
- Identify high/low risk zones
What to Look For in a DEM Provider
Not all DEMs — or providers — are created equal. Here are a few things to consider if you’re commissioning a DEM survey:
- Technology: Are they using LiDAR, photogrammetry, or both? Each has its strengths.
- Experience: Do they have proven results across industries like yours?
- Turnaround: Can they deliver fast without sacrificing quality?
- Deliverables: Will you receive data in usable formats (e.g., GeoTIFF, LAS, CAD-ready files)?
- Compliance: Are they CASA-certified to operate drones in your area?
Two70°, for example, ticks all these boxes. With a focus on accuracy, fast delivery, and practical outputs, they work closely with clients to deliver elevation models that serve real-world needs — not just pretty images.
The Future of DEMs in Australia
As climate change, urban growth, and resource challenges intensify, the demand for accurate terrain data will keep rising. DEMs will continue to play a key role in helping us adapt, plan, and build smarter.
Expect to see even more automation in how DEMs are captured and processed. AI and machine learning will allow for faster analysis and prediction. Real-time drone data could soon feed directly into live 3D modelling systems.
And with drone tech improving and becoming more accessible, even smaller councils, farms, and businesses can take advantage of terrain data once reserved for big-budget projects.
Conclusion
Digital Elevation Models aren’t flashy, but they’re foundational. They give shape to the invisible — helping us understand where water will go, how roads will be built, and what lies ahead.
In a country as geographically diverse and expansive as Australia, the ability to map terrain quickly and accurately isn’t a luxury — it’s essential.
So whether you’re managing a floodplain, designing a solar farm, or simply planning your next big build, a good DEM could be your most important tool. And thanks to drone specialists like Two70°, getting one is easier than ever.
FAQ
What exactly is a DEM?
It’s basically a digital map that shows the ups and downs of the land — but there’s more to it than that.
How do you actually make one of these models?
Hint: it involves drones, lasers, photos, and a fair bit of clever tech.
Isn’t that the same as a DSM or DTM?
Not quite. They all sound similar, but they each tell a different story about the land.
Why would anyone need a DEM?
Turns out, a lot of people do — from city planners to flood modellers and solar farm designers.
Are drones really better than traditional surveys?
Let’s just say they’ve made things faster, safer, and way more efficient.
How accurate are DEMs? Like, really?
Depends on the tech you use — but they can get impressively precise.
What do they actually look like?
Surprisingly cool. And when visualised right, they can do more than just look pretty.
How do I know if I’m getting a good DEM provider?
There are a few things to watch out for — tech, turnaround time, and local know-how included.
Curious about how DEMs can help your project? Check out Two70° for full-service drone mapping solutions across Australia.