Swimming to the Swimming Pool #2

Why is TCDC wasting huge sums of ratepayer funds pursuing the Thames airfield site for the proposed new aquatic centre when it has a minimal chance of being consented?  By all means promote a new aquatic centre in or around Thames, but the airfield is the wrong place for it. 

The airfield land is low-lying and is at significant risk, even in the short term, from coastal flooding by inundation, storm surge and via rising groundwater.

0.5 m sea level rise and storm tide

Our laws, Supreme Court judgements, policy statements, and guidance relating to coastal hazards all scream this directive – “don’t place major new capital projects on land potentially affected by coastal hazards over at least the next 100 years which increase the risk of social, environmental and economic harm”. Which is precisely what this proposal will do.

SLR table
Table from Ministry for the Environment Guidance

Council has received an interim report which naively suggests that the risks of coastal hazards can all be solved by simply building the seawall higher.

The report ignores local well-documented coastal land subsidence which adds to the risk of rising seas and groundwater intrusion beneath the wall because of sea level rise.   Will expensive pumping infrastructure be required here and from Kopu to Tararu?

National policy directives require sea level rise to be considered over “at least 100 years”. If current Ministry for the Environment sea level rise guidance is followed the seawall would have to be raised between 1.7 and 2.1 m.

This guidance is already out of date and will be reviewed annually.  Just released overseas guidance has sea level rise projections several metres higher than NZ’s. Which means by the time any airfield project gets to the consenting stage much higher sea level rise levels will need to be considered.

If the wall must be raised 2 m (or perhaps by 3 m metres or more) at the airfield this indicates that the entire seawall between Kopu and Tararu and other structures elsewhere around the entire district must be raised by a similar height.  At what cost?

Council has set aside funds for coastal hazard “Shoreline Management Plans”. Why the unseemly haste from the Council to push on with the airfield site when these plans have yet to be developed? What if these shoreline plans conclude that it will be just too expensive to provide protection everywhere, especially for new irreversible $20m projects where we still can avoid risk and future costs on ratepayers?  Surely we should concentrate limited ratepayer resources on protecting existing homes, businesses and infrastructure, and the Thames CBD?

Our laws and planning instruments make it abundantly clear that we should not be consenting major new projects on the coast which increase risk and future costs.  TCDC must look elsewhere for an aquatic centre site.


This what the aftermath of a storm surge over land less than 0.5m above sea level looks like –