Sea level risks to South Dunedin are dire – Thames even more so?

Stuff reporter Charlie Mitchell has written an excellent article about the serious risks to South Dunedin from sea level rise/groundwater.

The situation in South Dunedin is very serious.  But if you read his article and simply insert “Thames” for “South Dunedin” you may begin to appreciate that the situation in Thames is even more dire.

Why “more dire for Thames?”  –  because apart from groundwater flooding made worse by sea level rise, you must add three additional cascading risks for Thames that South Dunedin does not have

  1. The risk of direct inundation over coastal defences.

Moanataiari sea wall Thames

2.   Land subsidence of around 10 mm a year which exacerbates sea level rise (Dunedin has subsidence rate of just 1 mm year) . Watch this three minute video by Prof Tim Naish which explains why land subsidence matters.

And

3.    Potentially dangerous contaminants in the soil at Richmond Villas and Moanataiari and elsewhere on the foreshore which may be mobilised with rising groundwater and sea levels.

Local authorities in Dunedin have stepped up with comprehensive modelling of groundwater and meaningful community engagement.  It’s well overdue for Thames/Coast communities to also be shown due respect and properly informed about the potential risks they face.

(Charlie Mitchell is the reporter who wrote a similar in-depth article about sea level rise in Thames-Coromandel last year).