United Tunneling was engaged to complete a specialist microtunneling installation for the Frost Road GAJV project, delivering an underground crossing beneath the South Western Motorway.
The works involved installing 175 metres of 150mm steel caisson pipe, followed by 175 metres of 560 SDR9 PE pipe, using precision microtunneling methods. With a live motorway overhead, the project required careful planning, accurate alignment, and a trenchless approach that avoided disruption to one of Auckland’s key transport routes.
Traditional excavation was not an option, making microtunneling the right solution for a controlled installation at depth while protecting surrounding infrastructure and keeping traffic moving above ground.
Projects like this show how trenchless construction can deliver critical underground services in high-pressure environments where precision and reliability matter most.
Project highlights
Project: Frost Road GAJV
Location: South Western Motorway
Method: Microtunneling
Length: 175m steel caisson pipe + 175m PE pipe
Pipe Sizes: 150mm Steel Caisson / 560 SDR9 PE
Environment: Live motorway crossing
Need a trenchless solution under major infrastructure?
Talk to the United Tunneling team about the right approach for your next project.
