The Floods To Come

ON a freezing evening in March 2012, a sombre party of architects, planners, and local organisers met for dinner in the small Japanese port town of Ogatsu. Properly speaking, the town did not really exist any more, having been annihilated by the tsunami that struck the north-east coast of Japan’s main island, Honshu, almost exactly one year earlier.

Many buildings had been clawed away completely by the wave, others were flooded and gutted, and later torn down with bulldozers. The surviving population was dispersed to temporary housing units around the edges of the disaster zone. What was left was an empty, snowy  field of erasure on the banks of the Kitakami River, with only a newly-prefabricated strip mall to provide an ad hoc place of business for a few bereft shopkeepers and restaurant owners.

Over sashimi and tempura in one of those cramped prefab units, Professor Yoshiteru Murosaki was politely holding court. The head of architecture and civil engineering at Kobe University, and a respected authority on disaster management since helping to rebuild that city after the Great Hanshin Earthquake of 1995, Murosaki raised some modest rhetorical doubts about the government’s reconstruction plans for Ogatsu and other ruined towns along the Sanriku coast.

“So we move the residential areas to higher elevations,” he said. “We raise the level of the waterfront, and we erect taller seawalls. But how do we know the next earthquake won’t be bigger, and the next tsunami even higher? And what if it happens somewhere else, in some other part of Japan? Where do our defences start and end?” Professor Murosaki’s question might now be asked of every government of every coastal nation.

Not all port towns and cities face the same constant threat of extreme seismic violence that the Japanese have somehow learned to live with, though tsunamigenic seaquakes, underwater landslides and volcanic eruptions have also been known to occur in the Indian, Atlantic, and Mediterranean oceans with little or no warning – a sudden, fatal slippage in the Azores-Gibraltar fault line caused the razing and drowning of Lisbon in 1755. But hydro-meteorological hazards are ubiquitous to every shoreline, and they are gathering potential to do harm.

The Intergovernmental Panel on Climate Change (IPCC) has forecast a coming century of higher tides, heavier rains, stronger winds, and ever more severe storm surges, which when combined could hit a city just as hard as any tsunami in history. For evidence, consider the Indian Ocean tsunami of 2004 and Hurricane Katrina’s devastation of New Orleans the following year – very different disasters that exerted strikingly similar forces on buildings, bridges and other man-made structures, according to a joint study by civil and environmental engineers.

When Hurricane Sandy briefly swept the sea into New York, or vice versa, some seven years later, it was variously described as “yet another wake-up call” and “a disturbing sign of things to come” by Al Gore and other leading soothsayers of climate science. There are those who disagree that human industrial emissions are largely responsible for recent changes in the weather, but few now dispute that its patterns are becoming more capricious. Even fewer would deny that defences are required for those populations most exposed to flood risk.

In September of this year, the US-based research group Climate Central displayed their latest data on a world map that sized and coloured each country proportionate to its degree of exposure. The Netherlands appeared much bigger and darker than many other, larger Western nations, being so densely populated and so close to sea-level.

But the Dutch now lead the world in adaptive measures, having already allocated one billion Euros per year until 2100 for continuous improvements and refinements to its multiform mitigation system – a high-tech network of dykes, dams and floodgates augmented with natural buffer areas of salt marshes and sand dunes. Most of the map’s other danger zones were concentrated in Asia, and particularly in those south-eastern nations where rapid and largely unchecked urban development is occurring in low-lying coastal plains and along flood-prone river deltas – Vietnam, Thailand, Bangladesh.

Some of these countries are not now and may never be in a financial or political position to develop similar defences. Dr Benjamin Strauss of Climate Central, who co-compiled the map, put the problem in the simplest terms when consulted for this article: “Sea level rise is going to be acting on all of the coasts of the world, essentially at once. Some places will have the resources and foresight to plan ahead. Others will not be able or willing.” (Strauss also said that reduction of carbon emissions “may or may not be” an important factor in slowing that process, even if a timely agreement is reached between the world’s industrial leaders. Which is to say, it might already be too late for that.)

In terms of sheer numbers, there are more people now exposed to flood risk in China than in any other modern nation. But the People’s Republic has recently begun to turn its considerable economic power to the protection of its seaward megacities, spending hundreds of millions of yuan, for example, on enhancing the gates and levees that stretch for over 1000 kilometres along the Huangpu River and into the waterways of Shanghai. Japan, too, is both highly vulnerable and highly resourceful, a disaster-prone archipelago with a wealth of bitter experience and hard-earned expertise in defending itself from the ocean.

At the 2014 United Nations Climate Summit in New York, Japanese Prime Minister Shinzo Abe offered to share that expertise with other at-risk states in the developing world, through an international programme that will train 14,000 new specialists in seawall construction, meteorology, energy reduction and so on. But to get a better sense of what the most advanced science and technology can and cannot do, it’s worth going back to the Great East Japan Earthquake and Tsunami of March 11, 2011.

It was the most powerful quake in the country’s recorded history, and if state-of-the art seismographic equipment could not quite predict it , co-ordinated warning systems did send alerts from offshore detector buoys to monitoring stations to mobile phone networks within seconds. Hyper-resilient building codes enabled most modern structures to withstand an extraordinary degree of shaking, and a well-drilled general public duly responded in a calm and orderly way. In this respect, the Japanese model provided sturdy examples of best practice in disaster planning.

Then the tsunami followed, and exposed several more critical policy issues. Pressed for useable land between rugged mountains and fjord-like inlets, local authorities had permitted residential and commercial development at low elevations, dangerously close to the shoreline. Seawalls and emergency shelters had been designed with the last major tsunami in mind – the so-called “Chile Tsunami” of 1960, when a monumental quake in that country sent a pulse across the Pacific to strike northeast Japan with waves of over five metres. Previous tsunamis had destroyed many of the same fishing towns and villages in 1933, and before that in 1896.

But the waves generated by this latest quake were the biggest to hit this corner of Japan for more than 1000 years, swelling up to 30 metres over certain harbours before crashing inland. Having experienced nothing like it in 10 or 15 generations, many residents simply did not know or believe that such heights were possible. Even given half an hour of warning between the quake and that first wave – ample time for able-bodied people to evacuate to higher ground – thousands of victims did not start running, or climbing, until it was far too late.

In the months and years that followed, disaster management professionals have drawn out various lessons to be learned from this, which might now be applied to other countries with different hazard profiles. Elsewhere within the Pacific “ring of fire”, there are still developing island nations with a demonstrably limited understanding of seismic risks and responses, as seen across the Samoa and Tonga in September 2009, when a comparatively minor seaquake triggered a tsunami that killed more than 200 islanders.

Many of those victims had been trying to escape in their cars, when they might easily have survived by scaling the surrounding hills on foot. Or consider the case of Indonesia, where emergency warnings were still confined to TV broadcasts, even five years after the catastrophic Indian Ocean tsunami of 2004, and despite the fact that the most exposed rural populations largely live without household electrical appliances. Another tsunami had struck Western Sumatra in 2009, causing deaths that might have been prevented with a simple and affordable adaptation of the Japanese cell-broadcast alert system for mobile phones – which are now omnipresent in even the poorest communities.

Even in Japan, however, the most prepared nation on Earth, there had clearly been a fatal lack of awareness on the day of the tsunami, a cognitive problem that was hard to quantify and almost impossible to legislate for. “It’s a problem of history and memory,” said Masunori Kusaka that night in Ogatsu one year later, where the experts had gathered to compare notes over dinner.  An architect assigned to help rebuild the neighbouring port of Onagawa, Kusaka compared that task to “rebuilding Troy after the siege”.

He listed off the legal and logistical complexities involved, from insurance claims and inheritance rights to the question of popular consent. Many survivors, and especially the local fishermen, simply did not want to sell their land and move up the mountainsides, which were now being cleared and terraced to make new homes at safer elevations. They were “people of the sea”, said Kusaka, and they accepted the historical cycle of destruction and reconstruction.

The government, meanwhile, was trying to break that cycle by enforcing a permanent relocation, and other residents seemed willing to go along, if somewhat sadly and reluctantly. Kusaka expected them to drift back down to the shoreline within a couple of generations, as previous residents had done after past tsunamis. “It’s happened before, and it will happen again,” he said. “A wave comes, and people retreat. Then time passes, and people forget.”

What worried Kusaka about people in general was our tendency to think only in human timescales. If we have never seen a “100-year storm” or a “1000-year wave”, then we are barely able to conceive of such things, let alone begin to plan for them. And if we have seen and suffered these calamities, then we are inclined to believe that they cannot happen again, or at least not in our lifetime. “This is a fallacy,” said Kusaka, as his colleagues finished their meal. “And it is very dangerous.”

Standing outside in the snow, on the frozen wasteground where Ogatsu used to be, Professor Murosaki suggested that climate change might yet teach us to think differently, “because we won’t have to wait very long for the next disaster”. In the years since that meeting, the Japanese government and their contractors have begun work on a monumental defensive line of 440 concrete barricades along the perimeter of the Tohoku region – the so-called “Great Wall of Japan” that Murosaki had his doubts about. Any coastal engineer will tell you that even the strongest, tallest seawall can only stand for so long before being breached or overtopped, while its very presence often amplifies the stress on weaker adjoining areas.

The current consensus in the profession is that “hard” structural solutions can only work in tandem with flexible, sustainable approaches to shoreline management, and “soft” social countermeasures to help prepare and empower those front-line coastal communities who now literally live on the edge. Professor Robert J Nicholls of the UK’s Tyndall Centre for Climate Change is not the first to point out the political and economic ironies of disaster planning: those who can most afford it are no less likely to complain about the cost.

“It’s not true to say that the government, or the taxpayer, can’t pay for flood defence,” says Nicholls, with particular reference to his own country, which has lately been subject to frequent summer flooding, destructive winter storms, and invasive coastal erosion. “If we made it a priority, as we do with health or education, I’m sure we could make the funds available.”

The US too, has shown no real sign of initiative, nor developed what Nicholls calls a “planning culture”, with climate scientists and engineers obstructed by public and political ignorance even as Hurricanes Irene and Sandy have made investors and insurers start to wonder how viable the nation’s east coast cities would remain in a future of recurrent superstorms. At this year’s UN Climate Summit in New York, President Obama announced a mildly encouraging new set of executive orders that will factor “climate resilience” into all international development.

A new award was also given to the best-developed Global Disaster Resilience App, thereby encouraging the private sector and tech industries take a more active, innovative role. But the US, UK and other global leaders still have a little time to act, and room to manoeuvre – or even to retreat if their coastlines should eventually prove indefensible.

Also present at the summit was Anote Tong, the president of Kiribati, whose sea-level island nation has an estimated 20 years to live. “It’s inevitable,” said Tang. “Within this century, the water will be higher than the highest point in our lands.”

Some 100,000 residents of some 30 atolls are being gradually evacuated to New Zealand and Fuji, while President Tang travels the world to inspect melting glaciers and petition world leaders to join his government’s voluntary commitment to carbon neutrality. Kiribati is now building seawalls too, not to save the islands but to preserve just one – as a testament, and a monument. “So that something is left of the homeland,” Tong has said.

“And so our spirits have somewhere to go.”

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