Reducing Flood Inundation Hazard and Risk across Aotearoa New Zealand

Flooding is one of New Zealand’s most damaging hazards, which will also change the most rapidly in intensity and nature as a result of climate change. At the same time, urban development is leading to increased flood exposure. These dual challenges make reducing flood risk extremely difficult for our current planning and response systems. There is a knowledge vacuum about the scale of these problems, the integration of different policy domains, and the details of how different parts of the country will be affected. In this 5-year programme, we are working in partnership with NIWA and other organisations including universities, CRIs, local and central government and Iwi to support the changes that are needed to improve our management of flood risk. In particular, we will help to produce New Zealand’s first consistent national flood map, showing where flooding is likely to occur and the impacts associated with it.

The primary focus of our work will be to quantify the uncertainties associated with these predictions, particularly those which result from the representation of spatial data within hydraulic modelling. We will assess how uncertainty “cascades” through the modelling/ analysis chain, enabling us to determine our level of confidence with projected flood risk. This will provide policy-makers with the information needed to be able to make decisions despite uncertainty in scientific predictions. Uncertainty is a cross-cutting theme that will assess the drivers and consequences of uncertainty and work with end-users to design, test and establish novel decision-making practices.

Project leads: Dr. Emily Lane and Dr. Sam Dean (NIWA). GRI lead: Prof. Matthew Wilson.