The sea level rises putting thousands of homes at risk

PHOTO: The issue of managed retreats tend to fall in the Government’s lap, Climate Change Minister James Shaw says. Getty

From the ruins of the soon-to-be-defunct Resource Management Act (RMA), a new law is about to transform how New Zealand deals with the risks posed by climate change – and decide who foots the bill for our retreat from the coast.

Tens of thousands of coastal Kiwi homes could be deemed uninsurable over the next few decades thanks to a rapid increase in erosion fuelled by sea level rises, and a ‘managed retreat’ has been posited as a way to fix this very expensive looming crisis.

As it stands, however, no one is sure what a managed retreat should look like nor who should be responsible.

There are many questions still to be answered. How do you stop people buying homes near the coast? Whose problem is it when a home becomes uninhabitable, or infrastructure unusable? Do you reinforce the coast or just let nature run its course? Who pays for all this?

Finding answers to these complex questions is the challenge facing Climate Change Minister James Shaw and other legislators drafting the much-anticipated Climate Change Adaptation Act (CAA) this term.

How sea level rises are putting NZ homes at risk

Coastal erosion isn’t a new problem in New Zealand, but climate change is likely to accelerate it. That’s because as temperatures go up, glaciers and ice sheets melt and ocean water expands, causing sea levels to rise.

“By having an increased sea level, you will inundate more of the coast – so your coastline is automatically shifted landward,” Matt Rivers, a senior coastal engineer for Auckland Council, explained Newshub.

“[Sea level rises] allow in larger waves, and those will have greater energy because they won’t be dissipated by the shallow bathymetry offshore – so you’ll have greater wave energy coming in, and that will cause greater rates of erosion.”

Sea levels have been rising about 3.3mm a year since 1993 – and even if the world follows the most optimistic projections, it’s likely to have risen another 69cm between 2000 and 2100 /#