Reveal has provided a suite of subsurface detection technologies, supporting the delivery of the Eastern Busway project in Auckland, New Zealand. Reveal’s team discuss how these technologies and the project will benefit the community in the coming years.
The Eastern Busway is one of New Zealand’s largest transport projects, aiming to transform the way locals and visitors travel in and around the region for generations.
The project, which has an estimated total cost of $1.5 billion (per Australia New Zealand Infrastructure Pipeline) consists of four stages, all aiming to improve transport choices and connections in the region.
By 2028, the busway is expected to carry 18,000 passengers daily, more than four times the 3700 bus passengers per day before COVID-19. Despite delays and further cost and scheduling impacts from the COVID-19 pandemic, works on the project are powering ahead.
Major utility relocations are playing a fundamental role in the delivery of these works, an aspect that previously was often a difficult task due to incomplete, outdated and inaccurate utility records.
Reveal were approached by the Eastern Busway Alliance in late 2022 to develop a proposal for the works.
Luke Herlihy, Chief Product Officer – Reveal, says the project presented an ideal opportunity to implement a unified utility model – a new concept being developed by Reveal that combines existing network utility models held by asset owners with the results of geophysical investigations to produce a 3D model of the underground that has been verified to best-practice subsurface utility engineering standards.
“The main Busway is being put in the existing road, and the road is being widened to accommodate this. Utilities need to be relocated from the carriageway into a Combined Services Trench outside of the carriageway,” he says.
“These kinds of large construction projects are really utilities projects with a road on top of them.”
Reveal’s combined hardware and software approach to subsurface detections aims to provide a comprehensive picture of underground utilities, helping to increase the efficiency, safety and sustainability of works concerning the subsurface.
Utilities such as cables, ducts and piping can all be viewed and clearly identified from a centralised source in Reveal’s platform. Each object in the model has a chain of evidence and “trust score” attached to it, highlighting the sources of evidence and degree of confidence to the detection, so design engineers can make informed decisions about the risks of a particular excavation.
For the Eastern Busway, Reveal used a vehicle with a multichannel ground-penetrating radar (GPR) array to drive over and around the project area to supplement the traditional utility locating workflow.
Jordan Moratti, Project Delivery Manager for Reveal, says the company’s services helped to overcome the biggest challenge for the project delivery authority: the lack of records or knowledge around the location and variation of underground utilities.
“Putting myself in the client’s shoes, not having that firm understanding about what’s underground due to poor quality existing records or ‘unknowns’ from a design perspective, would be quite problematic,” he says.
“As they’re effectively extending the road out and then building dedicated bus lanes, it involves a huge amount of utility relocation. They don’t want utilities underneath the dedicated bus lanes, because obviously if there’s a fault with the utilities or they need maintenance they don’t want to have to shut down these bus lines.
“They’re building combined service trenches, so relocating most of these services to combined service structures. Utilities are a huge element for this project. That’s why they’ve had a real focus on trying to de-risk as much of the underground space, as early in the project as possible.”
Herlihy says these records also play a greater role in ensuring that a project can satisfy other requirements such as safe, timely and sustainable project delivery.
“Having that digital 3D model underground will help to improve health and safety outcomes, and importantly, improve the productivity and efficiency of delivering within the tight timeframes that the alliance had to adhere to as well,” he says.
Related stories:
- Reveal: Seeing, is believing
- Reveal’s model of proactive subsurface risk management
- Revealing the Riverlink
With the assistance of Reveal’s newly launched Underdots data processing service, the Reveal team transformed this raw data set into an easily accessible 3D model for the construction alliance.
Underdots is a software capable of translating raw ground-penetrating radar data into a 3D model, depicting the size and frequency of radar detections through grouped or clustered dots. Solid objects such as pipes, ducts and other utilities can be distinguished from surrounding soil, making Underdots an invaluable visualisation tool for getting quick insights into the underground environment.
Moratti says Underdots fuelled the efficiency and accuracy of the united utility model that was provided to the project delivery team.
“Underdots was a key change, because at the time of the project proposal, we hadn’t developed Underdots as a deliverable, so it was a change from what we initially proposed,” he says.
“The main benefit of that was the ability to give the delivery authority multichannel array GPR data faster. We did the capture in July and by August we had made Underdots available for the project. The final deliverable wasn’t until December, so traditionally they would have had to wait until we were fully finished to even get a glimpse of what was going on underground with the GPR data.”
This comprises 22.4 hectares worth of mapping within the unified utility model, a significant area covered for works such as this. This model could also be exported into BIM, 12d, AutoCAD and GIS compatible file formats.
All up, 20 per cent of the utilities in the Unified Utility Model were previously unknown assets.
“That [percentage] is standard for works such as this, but it’s fascinating how much in the underground that we just don’t know about or isn’t contained on any records,” Moratti says.
Since delivering this final data set, Reveal has provided ongoing service and support for the project delivery authority, who are actively seeking expertise around the data sets provided.
“We’re still providing answers to their questions around the data in the unified utility model. [The Eastern Busway project delivery authority] is actively doing a lot of potholing or daylighting of the utilities associated with the project. There is a bit of back and forth between us just clarifying specific utility information that they’ve found during their potholing,” he says.
“That’s the best quality utility information that you can get – what you can actually see in the ground. The intention is to assist them and help them to understand that information.”
Feedback from the client, as well as other construction partners, further points to the technology’s success.
“That feedback has been really positive. We managed to deliver in the timeframe that we agreed on at the beginning. Even with all the complexities of working around on site with other work parties, we still managed to complete the field works within the original program,” Moratti says.
“The client is really thrilled with the outcome and the data that we presented to them. All of the feedback has been really positive.”
Moratti adds that the potential for wider use of unified utility models, including Underdots, is an “extremely exciting” prospect.
“To be able to do these large-scale utility mapping works and then provide that to a client with a unified utility model provides great value for any project. I’m really excited to be able to undertake projects similar to this,” he says.
This article was originally published in the May edition of our magazine. To read the magazine, click here.
This article was originally published in the May edition of our magazine. To read the magazine, click here.