Installing new stormwater infrastructure beneath active railway corridors requires precision, careful planning and a solution that minimises disruption to rail operations.
Kerry Drainage & Civil delivered specialist trenchless crossings at Te Mahia and Takanini Railway Stations, completing the works within a scheduled KiwiRail Block of Line.
As part of the upgrades at Te Mahia and Takanini Railway Stations, Kerry Drainage & Civil was engaged by main contractor Oxcon as a specialist trenchless subcontractor to install new stormwater crossings beneath the railway tracks.
The works required new stormwater infrastructure to be installed beneath the railway corridor without conventional open excavation. Kerry Drainage & Civil also completed associated drainage works, including the online replacement of an existing 600mm-diameter stormwater pipe and the open-cut installation of a new public sewer within a CLS pipeline.
The railway crossings were completed using a trenchless drilling and pull-back methodology. A welded steel casing was installed beneath the railway tracks, after which a 180mm OD HDPE pipe was pulled through the casing. Pipe spacers were used to maintain the correct position of the PE pipe within the steel casing.
With railway infrastructure presenting significant access, safety and operational constraints, careful planning and sequencing were critical. The stormwater crossings were successfully completed within the scheduled KiwiRail Block of Line, allowing the wider station upgrade programme to progress as planned.
The project demonstrated KDCivil’s ability to deliver precise trenchless infrastructure beneath critical transport corridors, working within tightly controlled rail access windows and alongside other project activities.
