Coastal retreat 40 years off?

An update of coastal protection options has been completed by the HBRC-led team developing the region’s coastal hazards management strategy (first focusing on Clifton to Tangoio).

The bottom line is that so-called ‘planned retreat’ is not seen as needed (or at least as cost-effective) in the near- or mid-term. The tipping point where initial adaptation measures – e.g., groynes, wetlands, sea walls, beach replenishment – might cease to be effective is projected around 2065.

In brief terms, the current adaptation paths are as follows:

The technical team is refining the analysis of thresholds, signals and triggers that would move specific localities from one level protection to the next … including potential retreat. 

Looking beyond the near-term measures, a recent report for the Coastal Hazards Strategy Joint Committee commented:

An amazing amount of technical work has been undertaken to develop these alternative pathways, as well as commendable effort to socialise the findings and options with affected communities and stakeholders. Everything you might want to know about the strategy and its development is here.

Whether the engineers are adequately reading the future in terms of quickening global warming and its coastal impacts remains to be seen.

As the report cautions: “As always, evaluation of adaptation strategies is based on current knowledge about the risks of damage from climate change and the costs of addressing that risk. At any time new knowledge or weather events could render decisions obsolete.”

Amen!

Hopefully Mother Nature will allow ample time for our political leaders to figure out who is going to pay for coastal protection. That appears to be a much trickier challenge for the Joint Committee than sorting the protection options. The funding arrangement has been on the table since when I was a councillor … so that’s going back eight or so years now.