Coastal erosion is a significant hazard facing coastal communities throughout Aotearoa New Zealand and risk exposure of coastal communities and infrastructure is rapidly increasing as sea-level rise accelerates and a legacy of coastal planning decisions takes effect. However, we have incomplete knowledge of how our coastline is changing, where, and at what rate.

The purpose of the coastal mapping project was to provide a nationally consistent historic coastal change dataset. This information forms a key piece of the puzzle to understand the drivers of coastal change, including sea level rise, wave climate and storm conditions, sediment supply, vegetation, and human impacts. Understanding historic change and the drivers of change is crucial for improving models that provide projections of future change.

New Zealand’s National Coastal Change dataset provides the first nationally consistent coastal change dataset. We conducted the mapping at local scale, which means the dataset is appropriate for informing coastal hazard assessments, coastal planning, and decision-making.

The buttons below provide guidance on using this dataset, and how to use it in conjunction with other existing coastal datasets to inform coastal decision-making. We also provide guidance for tangata whenua on why these data may be useful and provide some case studies of how other whānau have been using the data.

Other important data sources for understanding and modelling coastal change (erosion and accretion) include sea level rise information available at NZ Sea Rise and wave, storm surge, and waterline shoreline data available at CoastalHub.