Climate Conversation Group

Seemingly sloppy science seems to have sullied our coastal planning process. Dr de Lange describes, in the polite, scholarly way of his, a scientific blunder in a Kapiti Coast erosion report that anyone less courteous than him would call a dereliction or worse. Why? Because the wrong formula was used to calculate the amount of foreshore vulnerable to damage from sea level rise, and many hundreds of properties are now apparently at risk. The report explains correctly why a certain formula should not be used, but then, in a stupefying about-turn, goes ahead and uses it anyway. Prices for those properties will plunge, yet the new risks just aren’t justified.

The author (or principal author) of the Kapiti Coast Erosion Hazard Assessment 2012 update is Dr Roger Shand, of Coastal Systems Ltd. He said the report was peer-reviewed by “Coastal Scientist Dr Mike Shepherd” – who effectively works for Dr Shand. Why didn’t they admit that they’re colleagues? This isn’t a peer review, it’s a pal review, and if values plummet, land owners will descend on the High Court demanding compensation. Does the District Council realise its exposure?  - Richard Treadgold

– by Dr Willem de Lange, Department of Earth and Ocean Sciences, University of Waikato

Recent news stories have highlighted the redefinition of coastal hazard zones along the Kapiti Coast. The populated region is concentrated on a coastal landform known as a cuspate foreland, which has formed due to enhanced accretion of sediment in the lee of Kapiti Island over the last 7500 years. Examination of the coastal landforms in this region indicates that there has been long-term accretion over the Holocene disrupted by storm-induced erosion associated with large waves from either the southwest or northwest.

Google Earth image of the Kapiti Coast showing the prominent cuspate foreland that has formed in the lee of Kapiti Island over the last 7500 years. (Click for larger version.)

So has that pattern changed recently? Read more… »