Case Study: Minimising Risk with Mappt


Subthermal use Mappt to plan large apartment and hotel project in Perth

If you don’t live in Perth, WA, you’re probably unaware of the massive growth spurt our small city is currently going through. Hotels, bars, apartments and parks are replacing empty spaces and growing faster than the newly planted trees.

One of the latest projects underway in the centre of the city is on a 4,926 square metre site on Murray Street. This block of land will soon succumb to two towers: one will house 407 apartments and the other will become a hotel with 487 rooms, restaurants, shops and some offices on the lower levels.

One company assisting with the build is Subthermal, a Perth based company that specialises in the design, supply and installation of geothermal environmental control systems.

Subthermal Director John Houdalakis is drilling an exploration pilot hole to work out which confined aquafer should supply the future buildings with water. Beneath Murray Street lie three confined aquifers, which are large bodies of water that aren’t exposed to the elements, and are tens of thousands of years old.

“Once up and running, it will be the largest geothermal project in Perth, one of the largest in Australia, and one of the top five in the Southern Hemisphere,” explains John. However, if you’re worried about the project’s environmental impact, don’t be, as Subthermal do not consume water, they pump it through the geothermal system and put it back again.

To complete a project of this scale, it’s paramount they use equipment and technologies to give them accurate results so they avoid mistakes that would cost them drastically in time and money. This is why Subthermal are using our mobile GIS, Mappt.




“There are a lot of services here that we could hit if we couldn’t identify where to drill, like Telstra, high pressure gas, sewage, high voltage electrical services, high pressure water mains etc. We use Mappt to overlay the Dial Before You Dig areas, and marker points to locate services, which prevents the drillers from hitting them,” says John.

“Once we do the overlay, we send the Mappt coordinates to the drillers, they download it onto their Android tablet, then we drill within inches of where we want it to be, so that reduces the potential to hit a utility service, which can be expensive and very hazardous.”

Hitting a service is a disastrous scenario John had experience before he began using Mappt. “Before we used Mappt we actually hit a sewer line at another site, it was five metres down, and we had to get a D9 excavator in and dig a 5x5m pit to fix the line. Expensive mistake!”

The worst part? This wasn’t Subthermal’s fault. To be on the safe side, John’s team drilled over 10 metres away from where the sewer line was estimated, but still hit it because there wasn’t an accurate record of where it was.


However, John has come up with a simple solution. “There are seven different utilities, so we’d like everyone to used Mappt as a standard platform. If Telstra, The Department of Water and Gas Co all used it to locate their services on a unified platform, that would be great. Right now they just give you a PDF hard copy, there’s nothing live!

“So rather than us submitting where we drilled, they have to upload it, then we have to notify five companies, it would be so much easier if everyone used Mappt as a central platform and could access the data in minutes.”

Sounds good to us!