Six cities fight against rising sea levels

Venice

A number of years ago, the Maldivian Government held an underwater cabinet meeting in an attempt to demonstrate the massive threat that rising sea levels, brought on by climate change, posed to their – and other pacific islanders’ – way of life. The tactic, although a little extreme, was deemed necessary in order to drive the point home – because, while for many people rising temperatures and tides are not something to be contended with in the course of their daily lives, by the end of the century this could all change.

In Venice, however, this is already a bitter reality. Each winter the city and its inhabitants must compete with the acqua alta – the name given to the abnormally high tide that sees floodwaters cascading through the city’s streets, damaging property and disrupting the day-to-day activities of Venetians and tourists alike. The destruction that has been caused by the annual floods, which have become a part of everyday life for the city’s 260,000 residents, is difficult to quantify. However, over the years the waters have caused a number of ornate buildings and historical monuments to suffer immense structural and cosmetic damage. One of the worst incidents occurred on November 4 1966, when the high tides left thousands of Venetians homeless and inflicted irrevocable damage on numerous artworks and books.

In a bid to push back the ever-encroaching waters and stop Venice from sinking into the sea, the government began work on the MOSE flood barrier project back in 2003. The €5.4bn ($5.9bn) installation is now in the concluding stages of its development. “Once the gates are in operation there will be a much better management of the lagoon”, explained MOSE’s General Manager, Hermes Redi, in an interview with The Guardian. “We haven’t had a problem with Venice sinking for the past 50 years – now our problem is the sea-level rising… With these barriers we will be the only city in the world which will be protected if the sea-level rises up to [one] metre. If water goes up more than [one metre] it is not Venice that is in peril, it is Italy.”

But despite Venetians’ best efforts, scientific research indicates that sea levels worldwide have been rising at an alarming rate and are likely to put many coastal and low-lying cities at risk of being reclaimed by the sea. In fact, according to National Geographic, a recent study claims that sea levels could “rise between 2.5 and 6.5 feet (0.8 and two metres) by 2100”, while other reports argue that “a complete meltdown of the Greenland ice sheet [could] push sea level rise to 23 feet (seven metres) – enough to submerge London”.

Amsterdam

There is a popular proverb in the Netherlands that states: “God created the earth, but the Dutch made Holland” – meaning that, when it comes to fighting against the forces of nature, the Dutch are in a league all of their own. After all, the Netherlands consists mostly of reclaimed land, with the majority of the country lying below sea level.

Over the years the Dutch have built a complex system of dykes, dams, levees and floodgates that collectively prevent storm surges and rising tides from taking back the land they already recovered from Mother Nature. Nowadays the Netherlands’ defences are more robust than ever – however, experts are reluctant to rest on their laurels, and so are constantly evaluating the flood protection system for any weaknesses. Not only that, but with land continually subsiding and global warming exacerbating the rate of sea level rise, the flood controls will require incremental upgrades in order to prevent a disaster from occurring in the future.

But the Dutch may be fighting a losing battle. Irrespective of the defences they have put in place, it is estimated that in 150 years from now, the water level may rise significantly and quickly enough to overwhelm Amsterdam’s defences entirely, allowing the ocean to reclaim what mankind once stole. However, not being the type of people to take defeat lying down, the Dutch Government began work on the Room for the River project in 2006: the plan, which has cost the government a little over €2.2bn ($2.6bn) to implement, will be completed later this year and hopes to address the issues surrounding flood protection and water management in the areas around the Netherlands’ four major rivers.

Hamburg

Venice and Amsterdam are certainly obvious candidates for nature’s hit list, but the second largest city in Germany is also at serious risk from flooding. After the Dutch capital, Hamburg is the next city in line to feel the full impact of global warming.

One of the worst floods to hit Hamburg occurred in February 1962, when waters from the North Sea caused the River Elbe to burst its banks, killing more than 300 people in the process. The memory of that event lives on among the local population and is often commemorated in the media. Since then the situation has improved considerably, as extensive protective measures have been installed – however, from the 1970s onwards, the frequency and intensity of high storm surges has increased, putting the city at even higher risk of flooding.

It has become quite common for the city to suffer flooding as a consequence of severe rainfall. Back in the summer of 2002, more than 20 trillion litres of rain fell over Germany, leading to what is known in the German media as the ‘flood of the century’. The event not only devastated Hamburg, causing millions of euros worth of damage, but also wreaked havoc on the city of Dresden, which is situated near the Czech border.

Climate change is expected to worsen conditions further over the coming decades, causing rising sea levels and intensifying storm activity across the North Sea region, which is in turn likely to put Hamburg and its state-of-the-art flood defence system at greater risk of being overwhelmed. To cope with the worsening conditions, the city’s barriers will be improved by 2030 – but no matter how good the city’s defences might be, if sea levels continue to rise as predicted, they will become rather redundant within a couple of generations.

Saint Petersburg

Nicknamed the Venice of the North, Saint Petersburg is one of the cities along the coast of the Southern Baltic Sea most at risk of being swallowed up by the rising tide. The impact of climate change is evident in the northern capital of Russia, with incidents of flooding expected to rise in conjunction with the increasingly warmer temperatures that the city has seen over recent years.

“In Russia, global warming is happening even quicker than average on Earth – in some parts of the country, especially in Siberia and in the Arctic, up to two times faster”, explained Vladimir Katsov, Director of the Voeikov Main Geophysical Observatory in Saint Petersburg, in an interview with Reuters. However, unlike other cities around the world, Saint Petersburg appears to be inadequately prepared for the worsening weather conditions and the increased probability of flooding that they could bring. As it stands, the Saint Petersburg Flood Prevention Facility Complex has built a barrier that is capable of resisting a sea level rise of up to six metres: while this is substantial in the short-term, additional work will need to be done to the city’s defences if sea levels continue to rise at such an alarming rate. However, there are those within Russia that question whether the country is even capable of covering the cost of such a project – or, incidentally, the cost of the consequences should no further action be taken.

“Russia’s economy is not ready for such risks, lacking adequate adaptation plans”, said Yury Safonov of Moscow’s Higher School of Economics in an interview with Reuters. He continued, “We’re seeing more last-minute action to tackle the actual emergency than a worked-out programme.”

Los Angeles

The City of Angels will eventually secure itself a much better view of the Pacific Ocean, with sea levels expected to rise by more than two feet by 2050, according to predictions made by climate researchers.

Climate change will bring higher temperatures and increased rainfall to Los Angeles, while simultaneously forcing its 12 million-plus inhabitants to endure even longer droughts. The rise in temperatures will also bring higher tides, bigger waves and larger storms, which might make surfers and beach bums rejoice, but will also give owners of beachfront properties serious cause for concern over whether their homes will get washed away by the ever-intruding shoreline. The fact that the city sits just three metres above sea level will also intensify the problem posed by global warming – in fact, according to climate researchers at the University of Southern California, by 2050 sea levels could rise so significantly that they begin to threaten public infrastructure, businesses and even negatively impact tourism.

“Some low-lying areas within the city’s jurisdiction, such as Venice Beach and some areas of Wilmington and San Pedro, are already vulnerable to flooding”, said Phyllis Grifman, lead author of the university’s report and Associate Director of the USC Sea Grant Program. “Identifying where flooding is already observed during periods of storms and high tides, and analysing other areas where flooding is projected, are key elements in beginning effective planning for the future.”

Luckily, the local government has been extremely proactive and is already in the process of identifying where the city’s major weaknesses lie, developing innovative solutions to the problems that they present in the process. However, if a storm on a similar scale to Hurricane Katrina were to hit the home of Hollywood, causing sea levels to rise just 0.5 metres, the cost of the damage could easily exceed $410m, according to the authors of the report. In addition, that cost could rise to more than $714m with a 1.4m sea level rise.

New Orleans

Hurricane Katrina – the third strongest hurricane to ever strike the US – hit the country 10 years ago, destroying the homes and livelihoods of millions of people all along the Gulf Coast, from Florida to Texas. One place suffered more than any other, however: New Orleans.

In just one day in late August, 53 of the Big Easy’s levees were breached by the storm surge, leading to severe flooding throughout the city and the deaths of more than 1,500 people. The failure of the city’s flood defences was due, in part, to the fact that its levees were only capable of withstanding category three winds (up to 130mph), but Katrina ranked at a five (exceeding 155mph). After the storm hit, more than 80 percent of the city was left underwater, with the severity of the flooding ending up costing the city more than $80bn in damages.

The reason the flooding and subsequent damage was so acute in New Orleans in particular is down to its geographical position: the majority of the city sits in a bowl-shaped dip which, at its lowest point, is situated more than 10 feet below sea level. The city’s low-lying location is why it has struggled – and will most likely continue to struggle – in its attempts to hold back the rising tides.

However, the municipality has since managed to step up to the challenge and has greatly improved its flood defences; installing a vast network of flood gates, dams and fortified levees in a bid to protect the birthplace of jazz music from ever having to relive the devastation that gripped the city just a decade ago. But despite the US Army completing the construction of the new multi-billion-dollar flood protection system in New Orleans late last year, there are a number of engineers and local officials that have expressed concerns about whether or

not the new system is fit for purpose. “Now, is what they built a good system, better than what it replaced? Yes, no question”, explained Bob Jacobsen, an engineer for the local Flood Protection Authority in an interview with The Lens. “But is it adequate? No, not given what’s at risk here.”