Waterview Tunnel project

Well-Connected Alliance

Sikagard Wallcoat T (ceilings), IMC Ceramicoat (walls), Concrete Plus Emer-Stop (T-beams)

Infrastructure, Waterproofing

About this Project

Topcoat Specialist Coatings Ltd played a key role in the successful completion of one of New Zealand’s largest infrastructure projects – the NZ Transport Agency’s Waterview Connection in Auckland. A specially-commissioned Topcoat team worked on the large-scale and complex project for more than two years.

The tender process was very specific; and the coating systems had to meet stringent criteria regarding vapour permeability and carbonation resistance. The concrete coatings on the walls and ceilings played a critical role in providing concrete protection and light reflectivity within the tunnels, which are located up to 45m underground.

The first stage involved high-pressure washing the extensive 95,600sqm of ceiling, and then applying the Sikagard Wallcoat T off nine-metre elevated platforms and scissor lifts. Following this, the Ceramicoat epoxy was applied to 44,500sqmof walls to a 4m demarcation line which was very specific as the tunnel shape was constantly changing contour and angles to support water run- off. Finally the concrete T-beams supporting the three-lane entrance and exits were also coated with 9,800sqm Concrete Plus Emer- Stop crème, to provide waterproofing protection.

Some of the challenges that Topcoat needed to manage included occasional leaks in the tunnel structure, as well as applying an epoxy coating to a cold surface. As well as taking daily records of surface and ambient temperatures, Topcoat carried out ‘dolly tests’ at every 100m, to ensure adhesion of the coating to the substrate.

Reflecting on the two-year project, Mark Ambridge says he’s proud of what his team achieved. “The project was challenging from a logistics perspective, as we were required to meet critical timeframes throughout,” says Mark. “It was testament to the commitment of our entire team – from our operations and admin support through to on-site personnel – that it ran so smoothly.”

The health and safety of the workforce was critical throughout the project, and Topcoat worked well to uphold the high safety standards that were set across the project. We often had a large number of tradespeople working in the tunnel at any one time, so coordination and cooperation was essential to achieve a successful outcome.The Topcoat team was flexible and worked very well with other teams.

David Taylor - M&E Sub-Alliance Manager