Your phone knows where you are.

It can guide you to the nearest café, track your morning run, tell you how far you’ve travelled and help you navigate through a city you’ve never visited before.

So, if GPS technology is already sitting in our pockets, why do we still need surveyors?

The answer comes down to one very important thing: accuracy.

Your phone is clever – but it’s not surveyor clever

The location technology in our phones is incredible. Using signals from satellites orbiting thousands of kilometres above Earth, our devices can calculate approximately where we are within seconds.

And for finding a restaurant or navigating to the footy, that’s more than enough.

But imagine you’re building a bridge, positioning a new railway line or determining exactly where one person’s property ends and another begins.

Suddenly, approximately isn’t good enough.

Without additional corrections, standard GNSS positioning can be accurate only to within several metres. By comparison, Australia’s precise positioning infrastructure can support positioning at the centimetre level, while specialised geodetic measurements can achieve even greater precision.

That’s where surveying comes in.

GPS is just one tool in the toolbox

Modern surveyors use incredibly sophisticated technology to measure and map the world around us.

And while we often call it “GPS”, surveyors actually work with GNSS – Global Navigation Satellite Systems. GPS is the American satellite system, but there are several satellite constellations operating around the world. Australia is particularly well positioned, with visibility to multiple global and regional navigation satellite systems.

Surveyors combine satellite positioning with technology such as total stations, laser scanners, drones, LiDAR, digital mapping and sophisticated software to collect and interpret highly accurate spatial information.

But here’s the important part:

The technology doesn’t replace the surveyor. The surveyor knows how to use the technology – and, importantly, how to understand what the data is telling them.

Why does a centimetre matter?

A few centimetres might not sound like much.

But when you’re constructing a multi-million-dollar building, installing underground infrastructure, setting out a road or determining a property boundary, small errors can create very big problems.

Surveyors help ensure that things are built in the right place, at the right height and in the right relationship to everything around them.

Their work supports the homes we live in, the roads we drive on, the railways we travel along and the infrastructure that keeps our communities running.

In the case of property boundaries, the responsibility goes even further. In Victoria, only a Licensed Surveyor is legally authorised to perform cadastral surveys that define property boundaries.

Your phone definitely can’t do that.

There’s another complication: Australia is moving

Here’s something you might not know.

The Australian continent moves around seven centimetres towards the north-north-east every year.

That might not sound significant, but when you’re working with highly accurate location data, it matters.

Australia therefore needs carefully maintained reference systems and positioning infrastructure so that measurements taken at different times can still be accurately related to one another.

It’s another reminder that determining exactly where something is located is far more complicated than watching a blue dot move across your phone screen.

So, will better technology eventually replace surveyors?

Technology will keep getting better.

In fact, Geoscience Australia’s Positioning Australia program is already helping make centimetre-level positioning more widely accessible across the country.

But better technology doesn’t make surveying less relevant.

It makes surveying more exciting.

Today’s surveyors aren’t simply measuring distances. They’re working with satellites, drones, 3D scanners, digital models and enormous amounts of spatial data.

They also need to solve problems, understand the environment they’re working in, interpret complex information and make decisions where accuracy matters.

So next time you open Google Maps and watch that little blue dot show you where you are, remember:

Finding your location is one thing.

Knowing exactly where something needs to be is another.

And that’s why we still need surveyors.