Defining the Flood Hazard in Takaka : a Town at Risk

The township of Takaka has an extensive history of flooding. Located adjacent to the confluence of the Takaka and Anatoki Rivers, previous events inundated large sections of the lower catchment and have raised issues for both Council and the community to work through relating to emergency management, planning controls, infrastructure and the influence of potential protection works.

A comprehensive 2-dimensional model has been established defining the flood hazard both for the township and the surrounding catchment. Outputs from this modelling process have been linked with the real-time flood forecasting product FLOOD Watch and the presentation and interrogation tool Water RIDE, to establish a cost effective real-time hazard prediction tool for the use of Council.

This paper looks to outline some of the unique features and issues encountered in the development of this project including: An overview on key aspects of the modelling process (including particular comment on the advantages and limitations on some of the tools used), a review on the effectiveness of some historical informal structures used to ìcontainî the river, a summary of implications and associated decisions for the community, and comment on potential development of real-time and predictive tools into the future.