Why Elevation Matters
Imagine you’ve just bought a block of land in Australia’s beautiful countryside, dreaming of building a home with stunning views. But then, the local council tells you your land is prone to flooding, and you’ll need to build higher than you planned.
This is where elevation comes into play. Whether you’re developing property, designing roads, or just curious about topography, elevation impacts everything—from drainage and erosion to how your house will sit on the land.
So, what exactly is elevation, and why should you care? Let’s break it down.
What is Elevation?
At its simplest, elevation refers to how high something is above a reference point—usually sea level.
In surveying, elevation helps us understand the shape and height of the land. Whether it’s a mountaintop, a flat plain, or a riverbed, every point on Earth has an elevation.
Surveyors measure elevation to ensure proper drainage, prevent flooding, and guide construction projects. It’s also crucial in urban planning, mapping, and even farming.
Types of Elevation in Surveying
Natural Elevation
This refers to the height of natural features like hills, valleys, and rivers. Surveyors map these elevations to understand how landforms affect water flow, soil stability, and construction feasibility.
Man-Made Elevation
When humans alter the land (e.g., by grading for roads, digging foundations, or building embankments), we create man-made elevations. These are critical for ensuring structures are safe and meet planning requirements.
Relative vs. Absolute Elevation
• Absolute Elevation → The height of a point above sea level (e.g., “Sydney is about 3m above sea level”).
• Relative Elevation → The height of a point compared to another nearby point (e.g., “The house sits 1m higher than the road”).
Both are important in construction, engineering, and flood management.
How Elevation is Measured
Surveyors use several methods to measure elevation, including:
🔹 Levelling Instruments – Devices like dumpy levels and auto-levels measure height differences between points.
🔹 Total Stations & GNSS (GPS) – High-tech equipment that uses satellites to pinpoint elevation with extreme accuracy.
🔹 LIDAR & Drones – Laser scanning technology (often mounted on drones) that creates detailed 3D elevation maps of the land.
The method used depends on the level of accuracy required and the type of project.
Why Elevation is Important in Construction & Land Development
Flood Prevention & Drainage
In Australia, many councils have strict rules about minimum floor levels for buildings in flood-prone areas. Elevation data helps determine where water will flow and prevents expensive disasters.
Road & Infrastructure Planning
Roads and bridges need careful elevation planning to avoid steep inclines, ensure proper drainage, and maintain structural integrity.
Building & Land Subdivision
When designing homes or commercial buildings, elevation affects everything from foundations to views and accessibility.
Surveyors provide elevation certificates to confirm land heights before construction begins.
FAQs: Your Elevation Questions Answered
How do I find out the elevation of my property?
You can check survey plans, topographic maps, or digital elevation models. Hiring a licensed surveyor is the most accurate way to get detailed elevation data.
Can I change the elevation of my land?
Yes, but modifying elevation (e.g., raising or lowering land) often requires council approval, proper drainage plans, and engineering assessments.
Why does sea level matter in elevation?
Sea level is the universal reference point for measuring elevation. Without it, different locations would use different baselines, making maps and construction plans inconsistent.
Final Thoughts
Elevation isn’t just about how “high up” something is—it’s a critical factor in land development, construction, and environmental planning.
Whether you’re buying land, building a house, or designing infrastructure, understanding elevation can save you from costly surprises.
If in doubt, always consult a qualified land surveyor—they’ll give you the elevation data you need to make informed decisions.