World's fastest sinking cities
Around the world, cities, especially those that are at the sea level, are finding themselves sinking at alarming rates. It’s a vicious cycle: cities dig deeper into the ground to extract water, leading to land subsidence, rampant development leads to large scale destruction of green cover, growing populations and upward construction of huge buildings are causing cities to collapse inwards, while climate change and erratic weather patterns are leading to rising sea water level.
Let’s look at some of the World’s fastest sinking cities including Jakarta and London: 1. JAKART A As per reports, 95 percent of North Jakarta is at the risk of getting submerged by 2050, if current rates continue. Climate change, excessive depletion of groundwater, rising sea levels, unchecked development and poor urban planning, have already led to parts of the city getting submerged. Adding to the danger is the fact that the city is built on an earthquake prone zone and is near the confluence of 13 rivers. Further, due to the lack of any piped water system in the northern parts of Jakarta, the city has to tap into its aquifers, leading to rampant extraction, causing land subsidence. The situation has become so alarming that the country is considering moving its capital to the island of Borneo. Indonesian President, Joko Widodo has asked the parliament to sign off on a plan to move the capital VIDEO 2. MEXICO CITY Home to around 21.2 million people, the metropolitan area of Mexico City faces the double predicament of suffering a major water crisis and sinking. The plundering of the surface water in the city goes as back as 500 years ago when the Spanish conquistadors captured the nation and depleting natural water resources, as they went about expanding their empire. Centuries of plundering led to surface water getting depleted as way back as in 1810. Over the past 60 years, the city has sunk by more than 32 feet as it digs deeper into its aquifers. This has caused many of the city’s buildings to lean, dangerously. Further, the 7.1 magnitude earthquake that struck Mexico City in 2017 has caused some areas to sink as much as 25 centimeters, 10 times the monthly average, as per a report by The Center for Research in Geography and Geomatics (Centrogeo). 3. BANGKOK The fact that the city is a low lying terrain, just 1.5 metres above sea level and that it is located at the southern end of the Chao Phraya River Basin means that Bangkok is already geographically susceptible to flooding each time heavy rains hit the city. Bangkok is also built on soft clay land, further exacerbating the situation. Climate change and rising sea levels, coupled with uncontrolled underground extraction of water leading to land subsidence, has caused the city to sink, as per a study by Thailand’s National reform Council, by 2 cms every year. The city is trying to tackle the situation; one of the steps taken by Bangkok was to create a 11 acre park which holds a million gallons when it is raining, in Chulalongkorn University 4. OSAKA The former capital of Japan is home to 2.5 million people, and is an important economic centre. Despite the fact that Osaka city already has defences such as seawalls in place to protect against tsunami, the Union of Concerned Scientists fear that USD 1 trillion of the city’s assets could be at risk by 2070’s. The Kansai Airport, which is built on a man-made island in Osaka Bay, for example, has been sinking gradually ever since it was opened in 1994, despite the airport’s runways and taxiways getting paved and raised a few times 5. ROTTERDAM The largest port in Europe, Rotterdam has 90 percent of its area below sea level. It also sits on a plain which absorbs outflows from the rivers Scheldt, Rhine and Meuse, hence putting the city at risk of flooding whenever it rains heavily. In 1953, a great storm which swept in from the North Sea, flooded parts of the Netherlands, killing nearly 2,000 people. But Rotterdam, which was rebuilt after heavy bombing in World War II, has been quick to prepare itself. The city has built water parks, which hold in the water, functioning as water reservoirs during storm water surges and when water level surges. 6. SHANGHAI Shanghai, amongst the world’s most populous cities, has been gradually digging its own grave – rampant and uncontrolled construction and excessive groundwater extraction has caused the ground beneath the city to press down on itself. The city sits at the mouth of the Yangtze River, further putting it at danger of flooding and sinking. As per reports, the Central Business District of Shanghai has sunk by 2.6 metres since 1921, when the first surveys were conducted. The city authorities are, however, trying to mitigate the problem. Shanghai has switched over to using water from the river for its daily use. It has also built seawalls which could help protect it from rising waters to some extent. 7. MANILA With a soaring population and a growing economy, the demand for water has increased manifold, causing large scale exploitation of groundwater resources. Sections of Manila have been sinking over the past few years, largely due to the excessive extraction of groundwater. Since the 1960s, sea levels around Manila have been rising significantly, and, by 2050, the sea is estimated to rise by another 50 cms. Indiscriminate development with scant regard for environment, improper disposal of garbage the coastal areas, have all led to floods becoming an annual phenomenon, while the residents of Manila have become used to wading through water and taking out boats. 8. LONDON A report released by Christian Aid has identified London as one of the cities under threat of major flooding and sinking as climate changes cause sea levels to rise. The increased instances of flooding has led the city to use its main flood defence, the Thames Barrier more frequently. When it was first opened in 1984, it was predicted to be used around two to three times a year, this has gone up to twice the rate to six-seven times a year 9. MIAMI Amongst the cities most under threat of sinking, Miami is located just 6 feet above sea level. A 2018 report by the Union of Concerned Scientists had stated that around 12,000 houses on Miami beach are in danger of chronic flooding in the next 30 years. In certain parts of Miami, the streets get flooded even when it is not raining – a full moon night and high tide cause waters to fill up the streets. This constant flooding has caused damage to roads, buildings and other infrastructure, and has also affected drinking water 10. ALEXANDRIA With a population of five million, Alexandria is Egypt’s second largest city and its main port city. According to reports, Alexandria would be completely submerged in water should water levels rise by 6 feet. While climate change is causing the sea level at the Mediterranean to rise, an increase in development, often right up til the coastline, is slowly eroding the city’s foundations. In 2017, Alexandria suffered devastating floods which caused deaths, destruction and millions of dollars of lost revenue. The Intergovernmental panel on Climate Change (IPCC) states that the Alexandria lowlands, on which the city is built, are vulnerable to waterlogging, inundation, waterlogging, increased flooding and salinisation as sea levels rise 11. DHAKA Bangladesh’s capital city is sinking at the rate of 1.27 cms, annually. Extensive extraction of ground water has led to land subsidence and flooding. Inadequate drainage, loss of natural protection such as mangroves and green cover and increased construction are all threatening the city.