Ōtaki to North of Levin Highway Hydrogeological Assessment

For over a decade, our team has been supporting Waka Kotahi on the Ōtaki to north of Levin (Ō2NL) transport corridor—a program of works to improve safety, resilience, and planning to increase transportation options for the area’s growing population.

A portion of the services we provided has focused on the hydrogeological elements of the new offline highway. Part of our responsibility was to provide a technical assessment to support the Notice of Requirement and resource consent application. We undertook a comprehensive site investigation including literature and data reviews, borehole installation, field testing and monitoring, and geological and hydrogeological modelling. We also interpreted data to support the assessment of environmental effects (AEE) to determine ecological and water user impacts. The analyses also informed other types of AEEs for the project, including terrestrial and aquatic ecology (wetlands).

The knowledge gained by our assessments was used to help the client, iwi, stakeholders, and community groups understand the hydrogeological aspects of the project and give them the confidence to make informed decisions. By collaborating across our multidisciplinary teams, the hydrogeological work has contributed to ensure that the new highway is much more resilient, thereby ensuring access to communities is retained for the future.