Restoring Track Performance at the Matapihi Rail Crossing

The Matapihi rail crossing in Mt Maunganui, Tauranga, had experienced notable subsidence, causing the track and surrounding ground to settle unevenly. This unevenness created significant disturbances for vehicles travelling over the crossing and raised concerns about long-term safety and performance for rail operations. KiwiRail required a fast, reliable, and non-invasive solution to restore correct levels and ensure a smoother, safer crossing for both rail and road users.

Mainmark implemented a precise ground correction program using Teretek® engineered resin injection to lift, level, and re-support the affected railway track. Before work began, the team surveyed existing ground levels and developed a treatment strategy involving angled 1-metre injection tubes placed at a depth of 500 mm from outside the track slab. Once on site, the resin injection process was carried out in controlled stages to provide the required lift while maintaining track stability throughout the operation. During the treatment, the track being raised by up to 94 millimetres to meet the project requirements. The opposite side of the track was then carefully adjusted to create the required camber, ensuring the final geometry aligned with KiwiRail’s specifications. Throughout the process, multiple checks and tests were undertaken to verify accuracy, and KiwiRail remained closely involved in reviewing and approving each stage.

The project successfully lifted and levelled the Matapihi rail crossing, achieving the required lift. The outcome delivered a smooth, cambered, and correctly aligned track in accordance with KiwiRail’s requirements. All ground levels and track geometry were verified through repeated testing, including confirmation runs with the tamper train. KiwiRail expressed satisfaction with the result, and the project was completed, documented, and handed over as a successful example of Mainmark’s ability to restore critical rail infrastructure quickly, safely, and with minimal disruption.