Kahika No.1 Culvert

Background

The road to Kahika Culvert was destroyed in the flooding caused by Cyclone Gabrielle in February 2023. The culvert itself was intact, but almost completely blocked by silt and debris.  The floodwaters washed out the road adjacent to the culvert and a temporary culvert and road has been constructed while the permanent solution is developed.

To date, extensive clearing of silt and flood debris has been done, along with topographical surveys and geotechnical investigations. These have informed a feasibility study and the development of options for engineering a permanent repair that meets hydrological and resilience criteria. A preferred option will be selected early in 2024 and construction will begin once all necessary consents and resources have been attained.

Construction of a permanent solution is expected to be complete by late 2025.

As well as the destruction of the Kahika Culvert, another four large culverts and thirteen bridges were destroyed. The focus now is on repair and restoration across the network. A programme of rebuilds and repairs has been developed with an estimated cost of $800 million. Due to the scale and complexity of the work required, this will likely take seven to ten years to be completed. Hastings District Council is prioritising work based on the vulnerability of roads to new weather events, levels of road use and the numbers of people affected. 

Key points

• Project timeline: Construction of a permanent rebuild is expected to be completed by late 2025.