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Kennedy Road SW crossing – Tauranga City

United Tunneling was engaged to deliver a specialist underground installation at Kennedy Road SW in Tauranga City, working beneath a busy collector route where maintaining surface access was critical.The project involved installing 48 metres of 2500mm steel pipe, jacked to a depth of 11 metres, supported by extensive sheet piling and a large launch box excavation measuring 11m long x 5m wide x 6m deep.Given the scale of the pipe and depth of installation, careful planning and robust temporary wo...

Ngaruawahia rail crossing – NIMT Twin Line

United Tunneling was engaged to deliver a trenchless installation beneath the North Island Main Trunk (NIMT) twin rail line at Ngaruawahia. The works required a controlled crossing beneath an active rail corridor, where maintaining rail operations and ensuring ground stability were critical.The project involved 40 metres of 1000mm steel pipe installed using auger boring at 2.5 metres depth, with an 800mm SDR21 PE pipe installed inside the steel casing. Sheet piling was used to form and support t...

Putaruru trenchless works – Kinleith Rail & SH1 corridor

United Tunneling delivered a series of trenchless installations across Putaruru, covering rail, highway, and local road crossings. The works required a mix of microtunneling and auger boring methods to suit different ground conditions, depths, and infrastructure constraints.The first stage involved 36 metres of 400mm steel caisson microtunneled at 4.0 metres depth beneath the Kinleith dual rail line, requiring precise alignment and strict control beneath live rail infrastructure.The second stage...

Taranaki Sewer upgrade – State Highway 3 crossing

United Tunneling was engaged to complete a trenchless sewer installation in Taranaki, delivering works beneath State Highway 3 and tying into an existing stormwater box culvert.The project involved installing 54 metres of 150mm PVC restrained sewer pipe at a depth of 10 metres, using microtunneling methods to maintain accuracy and minimise disruption to the busy highway above.The alignment required careful control to ensure a precise connection into the existing stormwater infrastructure on exit...

Frost Road GAJV crossing – South Western Motorway

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’...

Cobham Drive crossing – State Highway 1

United Tunneling was engaged to deliver a specialist trenchless crossing beneath State Highway 1 at Cobham Drive. The project involved installing 80 metres of 1500mm concrete jacking pipe at depths of up to 11 metres, using pipe jacking methods supported by sheet piling works.With a major transport corridor overhead, maintaining traffic flow and minimising disruption were key priorities. Open trench excavation was not a practical option, making pipe jacking the right solution for a safe and cont...

City Rail underground crossing – Auckland

United Tunneling was engaged to deliver a specialist microtunneling installation as part of works connected to the City Rail project in Auckland. The job involved installing 300 metres of 560 SDR9 PE pipe at depths of up to 26 metres beneath New North Road.Working in a busy urban environment meant surface disruption needed to be kept to a minimum while maintaining strict accuracy underground. With depth, existing infrastructure, and live traffic corridors all in play, traditional excavation wasn...