Delivering impact through trenchless construction project

A trenchless construction project is transforming Queensland’s infrastructure with smart delivery and strong community ties.

In the fast-growing corridors of the Sunshine Coast, delivering critical infrastructure ahead of population growth is more than a construction challenge – it’s a test of foresight, coordination and innovation.

Unitywater’s Aura and Harmony Water and Wastewater Program, in partnership with McConnell Dowell, shows what’s possible when trenchless technology meets collaborative project delivery.

With two 12-kilometre pipelines and a complex network of reservoirs, pump stations and water transfer infrastructure, the $190 million program serves the fast-developing communities of Aura and Harmony near Caloundra. These areas are expected to accommodate more than 70,000 residents by 2050, and the infrastructure now taking shape will serve them for decades.

Trenchless technology enables high-impact delivery

The decision to deploy trenchless construction techniques was driven by multiple imperatives: protecting high-density residential zones, reducing surface disruption, and accelerating delivery through difficult terrain.

A key method used throughout the program was horizontal directional drilling (HDD), which allowed engineers to install major pipelines beneath roads, driveways and natural features with minimal disturbance above ground. This approach proved particularly valuable when navigating sensitive areas, such as parks, school zones, and heavily trafficked pedestrian and cyclist zones.

Purdey Wikman, stakeholder and communications manager at McConnell Dowell, said the complexity of the works demanded both innovation and adaptability.

“If complex construction projects were easy, everyone would do it,” Wikman said. “It’s truly the relationships that make the difference. Responding quickly, finding solutions – this builds trust. The community saw that, and it has been critical to the project’s success.”

HDD also allowed for the integration of broader environmental protections. Watercourse crossings and culturally significant areas were completed with minimal ground disturbance, thanks to thorough planning and collaboration with traditional custodians, the Kabi Kabi peoples. Their involvement shaped a tailored Cultural Heritage Management Plan, integrating heritage considerations into daily construction practices.

Strategic planning supports rapid regional growth

The trenchless construction project supports Unitywater’s broader goal of futureproofing water infrastructure to match population expansion in the Sunshine Coast region. With projections indicating tens of thousands of new residents by mid-century, early investment in water and wastewater pipelines is vital to sustainable growth.

Joshua Zugajev, executive manager of strategic engagement at Unitywater, said planning played a key role in minimising future network strain.

“Every aspect of the infrastructure has been planned with this future community in mind, ensuring the network can meet demand for decades to come,” Zugajev said.

The program consists of three integrated works packages: Aura Water, Aura Wastewater and Harmony Water. In addition to the 12-kilometre water and wastewater pipelines, a dedicated 2.6-kilometre line was constructed for Harmony, accompanied by two 12-megalitre reservoirs and a new wastewater pump station. These assets connect to Unitywater’s broader regional systems and support reliable service delivery under peak load conditions.

While the bulk of the program was executed through trenchless methods, open trenching was also used strategically, particularly in areas where surface reinstatement could be carefully managed or where conventional installation offered cost or timing advantages.

Community engagement enhances technical outcomes

McConnell Dowell found that the success of the trenchless construction project, like many others it has completed, was shaped not only by engineering, but also by the community trust it earned from the outset.

Before construction began, McConnell Dowell initiated face-to-face conversations with local residents, schools and businesses. The aim was to set expectations, listen to concerns, and prevent the type of surprise disruptions that can often erode public confidence.

“From the very start, we focused on speaking to as many people face to face as possible,” Wikman said. “We shared information across different platforms, helping people understand both the purpose and benefits of each of the projects, as well as the potential impacts.”

Designs were regularly reviewed through a community lens, particularly in areas near schools or pedestrian routes. In several cases, plans were revised to address community input, even when technically feasible designs had already been finalised. According to Wikman, Unitywater’s openness to adjustment was crucial.

“Having a client like Unitywater, who genuinely embraces that approach, has made a real difference,” she said. “It has allowed us to adjust aspects of construction to minimise disruption and achieve better outcomes for local residents.”

This community-first approach extended to frontline construction activity. In one instance, access routes were modified to accommodate a resident with limited mobility. On another site, crews adjusted fencing to preserve a young boy’s collection of stone towers built beside the project boundary. Such gestures deepened engagement and transformed residents into project supporters.

Partnerships and legacy drive long-term impact

Inclusion and social procurement were key performance areas embedded in the project. More than $120 million has already been returned to the local economy, exceeding the original $80 million target. Over 85 per cent of employment was sourced locally, and more than $5 million in spending was directed to First Nations businesses for services ranging from protective equipment to cultural training.

One of the most powerful legacies came from a partnership with The Compass Institute, a Sunshine Coast-based social enterprise supporting people with disabilities. Compass trainees contributed more than 600 hours to maintaining the site garden and vehicles, while also gaining hands-on workplace experience. The collaboration deepened through access and inclusion training for project staff and culminated in McConnell Dowell receiving the 2024 Compass Heritage Spirit Award.

“It has been wonderful to witness the positive impacts, on the ground and through our collaborations with construction partners and local community groups,” Zugajev said. “It has also delivered positive outcomes for Unitywater and McConnell Dowell, the most significant being inclusivity in action.

“Team members formed friendships with the trainees, and there was a genuine sense of belonging. It improved understanding, broke down barriers, changed mindsets, and left a lasting mark on the culture of the project team.”

For more information, visit mcconnelldowell.com and unitywater.com