Geotechnical investigations are an important part of detailed design as they look at ground conditions, including soil and rock types, groundwater depths and the strength of soil and rock to guide the planning and design for the new road. We carried out this work between April and August 2025, and specialist equipment including drill rigs were used to take ground samples.
Data from these investigations showed a lot of variation in soil conditions across the project area, with silt, sands, and dense gravel all present in different locations.
Results gave us important insights into the soil conditions and potential liquefaction risks in the area. This information helps engineers design foundations for the new bridge structures and interchanges and to plan ground improvement work needed to support the new road embankments.
We worked closely with mana whenua during this work and cultural monitors were present on site during the works to ensure that all activities were managed in a culturally appropriate way.
Ecological and environmental assessments (like noise and flood modelling) were also completed during this time.
