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Areas Susceptible to Coastal Instability and Erosion (ASCIE)

The Auckland region has a high exposure to coastal hazards including coastal instability and erosion. These hazards can present a safety risk, adversely affect property and infrastructure, and damage or destroy cultural and environmental sites. A program of research has been undertaken to identify, at a regional level, the Area Susceptible to Coastal Instability and/or Erosion (ASCIE). ASCIE is the area landward of the current coastline that is at risk because of coastal erosion or instability caused by coastal erosion. The study forecasts the areas of Auckland’s coastline that could be affected by coastal erosion and instability under a range of climate change (sea-level rise) scenarios and timeframes. This data is mapped at a 0.5 km to 5.0 km scale and is not intended for site-specific use other than to determine whether more detailed study is warranted. Due to the large scale of the assessment (i.e., 0.5-5 km resolution) errors are inherently introduced due to the variance within a coastal cell. To identify areas that could potentially be susceptible to coastal instability and/or erosion typical upper bound values have been adopted for each coastal cell. This means that in some areas the ASCIE may be overpredicted (i.e., shown further landward). However, this also means that in ASCIE may be underpredicted in areas where values are larger than the typical upper bound value (i.e., the largest or maximum values). Therefore, this assessment is recommended to be used as a preliminary tool. The regional-scale ASCIE can be refined by undertaking an assessment on a more detailed scale. The purpose of the ASCIE identified within this ‘first-pass’ assessment is that they represent land potentially susceptible to coastal erosion and/or land instability associated with this erosion at a regional scale for present day conditions and a range of possible future climate change states. This means the areas outside of the identified ASCIE may be considered unlikely to be susceptible. It should be noted that this ‘first-pass’ assessment has been undertaken at a high level (regional scale) and may be superseded by local (Level B) and site-specific (Level C) scale assessment by a suitably qualified and experienced practitioner. This ASCIE mapping should not be used for the assessment of the erosion susceptibility of individual properties. As a ‘first-pass’ assessment it may include significant inaccuracies at localised levels. Assessment of individual properties (e.g. for consenting, valuation and insurance purposes) should be based on a site-specific (Level C) geotechnical assessment prepared by a suitably qualified and experienced practitioner. Public release is available for this dataset under a Creative Commons license

Being able to apply or incorporate this data into GIS software for the purpose of accurately comparing regional scale assessments (Level A) with site specific (Level C) assessment for Coastal Hazard Assessments.

The note on the AC Geomaps states that the data is available...."Public release is available for this dataset under a Creative Commons license" but there is no download link at the folllowing

Please make this regional scale assessment data available. or even just send to me! please!

making sure data is accurately represented and when AC review Coastal Hazard Assessments, they can be sure the data is valid and accururate.

Response from
Auckland Council

Preparing data for release

This data will be made publicly available on the Auckland Council Open Data Portal (accessible at within a month.

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