The Dutch Can’t Save Us From Rising Seas

Dutch engineers are renowned for their ability to keep cities dry. But their approach doesn’t necessarily translate to a New Zealand context.

One of the most common responses to the threat of sea level rise is to dismiss it by citing the Dutch example – nothing to see here – move on – the Dutch have built these enormous dykes so we can just do the same here in New Zealand.  There see – problem solved.

We see this thinking here in Thames where the District Council is promoting a major new aquatic centre on land known to be at high risk of coastal flooding.  The response from the consulting engineers – just build the wall (higher – and Mexico or future generations will pay for it?)

So, is this a realistic response here in New Zealand?  Not according to this article from Ian McHarg who looked at these issues for the USA – but many of the same arguments apply here.

“Americans are turning toward the Dutch because, in their telling, they have a success story to share—a rare glimmer of hope in cities facing the existential threats of sea-level rise, storm surge, and mass human migration.

Over the last half-century, the Netherlands’ coastline has been completely transformed through massive feats of engineering aimed at keeping its major cities dry. Dykes and levees, pump stations and retractable barriers, polders and reinforced dunes have all been erected in a national initiative to hold back the floodwaters of the North Sea.

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With this expertise, many say “The Dutch are coming to save us, if only we’d let them.”

But I’m not so sure. Although the United States has much to learn from the rest of the world’s approach to climate change, it’s not clear how or why we should expect the Dutch approach to adaptation to translate so readily to our shores. There are major, perhaps irreconcilable differences in the nature of the flood risk, the physical and economic geography, the political systems and institutions of each nation.

It would be difficult to imagine two nations in the Global North with less in common when it comes to flood risk. Designing a coastal barrier system like Holland’s is a simpler, cheaper proposition when the frequency and intensity of the storms are markedly lower than those experienced in the U.S. More American cities should question whether the Dutch approach will transfer so readily to their coast.

To put it bluntly, there is nothing remotely comparable about the nature of the risk in the Netherlands and the nature of the risk in the United States.

The two nations also differ considerably in their physical and economic geography. The Netherlands is a small nation with three major cities all clustered along roughly 1000 km of coastline.  (The Coromandel Peninsula alone has 400 km. New Zealand has 15,000 kilometres 

That brings us to the greatest discrepancy in the argument that what worked in the Netherlands can work in the U.S.: Each nation is operating under dramatically different political and infrastructure financing systems. The Dutch have high tax rates and a strong, centralized, activist government that, as a matter of survival, has to invest in coastal protection. Climate adaptation isn’t left up to the market in the Netherlands (or largely to local government as it is in New Zealand). From the capital costs of construction to the annual costs of operation and maintenance, the Dutch fund their protective barriers as if their lives and livelihoods depend on it—because they do.

Worse, the high cost of maintaining coastal infrastructure is borne by local governments.  (As it is also in New Zealand) In practice, this means that most cities cannot afford to maintain the protective systems they already have, let alone a massive, complex surge-barrier system such as the Dutch have installed.

(This next paragraph also applies to New Zealand)

As a result, the American coastline is a patchwork of uneven protection, ranging from substandard to non-existent, with the most protection found in wealthy areas with a local tax base to support the private financing of infrastructure, and little or no protection found elsewhere.  (eg. seawalls at Mercury Bay but little elsewhere)

No single approach—let alone an extraordinarily expensive, complex one like the Dutch approach—will work in a nation as large and diverse as the U.S.

Instead, governments can give coastal residents the two resources they need most to adapt: time and money. Smaller, nature-based coastal infrastructure can forestall, not halt, sea-level rise, giving residents some agency over when they leave and where they go—a decision that’s often made for them after major storm events.

We are entering the uncharted waters of planetary climate change. Dutch walls and dikes can’t stop that, and the Dutch approach to adaptation cannot save us—nothing can. But investments in community organizing and a more modest set of design tools can lessen its impacts and give people a chance to remake their lives, and the coast, for a wetter, uncertain future.”