After suffering its worst floods for a century, the Indian city of Chennai is consulting cities all over the world – from New Orleans to Jakarta – about the ambitious projects that could reduce their risk of flood devastation
Last month the city’s municipal body, the Greater Chennai Corporation, organised a seminar with 100RC in which international experts on flood management put their heads together with local experts to come up with a comprehensive plan to build a stronger, more flood-resistant Chennai. These are some of the cities and projects that Chennai attempted to learn from.
Chennai and the Caribbean city of Georgetown may be 15,000 km apart, but the problems they face are the same. Rapid unplanned urbanisation in Georgetown, as in Chennai, has resulted in what was once a well-connected network of canals and drains being built over. Floods now frequently inundate Guyana’s capital, and it has brought in experts from Arcadis, a global design and engineering firm, to come up with a plan on how to handle the problem.
As the pioneers of flood mitigation systems, the Dutch have battled floods for centuries as they protect a country that lies partly below sea level. The Dutch government, in 2006, began implementing a €2.3bn (£1.8bn) project called “Room for the River”. The idea was simple: make more room for the river to overflow, rather than building right on its banks.
In 2007, global attention turned to the Indonesian capital Jakarta as floods ravaged this bustling megacity, displacing at least 340,000 people from their homes. Once again, Jakarta and Chennai share many similarities: both are coastal cities with rivers running through them, and both cities are sinking – a phenomenon known as subsidence – due to extreme extraction of ground water and unplanned construction.
New Orleans, United States
In 2005 Hurricane Katrina devastated the city of New Orleans, leaving almost 1,500 people in the city and surrounding areas dead. After much soul searching, in 2010 the Greater Orleans Urban Water Plan was finally implemented: an attempt to create what its architects called a “Living Water System”, where canals were widened and their surroundings turned into green public spaces. New Orleans has since also put in place pervious pavements, which allows rainwater to pass through them into underground storage basins.
Chennai could well learn lessons from closer home, too. Surat, a city in the western Indian state of Gujarat, has put in place early flood warning systems to ensure that loss of life is minimised among its teeming population. It has also managed to restore a clogged and polluted lake, and has turned the surrounding area into a public space replete with entertainment and games for children and adults.
“Chennai’s residents will benefit if similar flood warning systems are put in place since this will give them some respite time to move away from the area,” says Kamlesh Yagnik, Surat’s chief resilience officer, who worked with municipal authorities to enable these projects. “Water bodies can also be cleaned and restored using the public-private partnership model, as we did in Surat.”
As the floods have become politically sensitive in the city, and with state elections looming, Chennai’s residents are at a unique juncture to demand a sustainable plan for a more resilient, “blue” city.
“After big disasters there are windows of opportunity,” says Michael Berkowitz, the 100RC president. “People are shaken out of their comfort zones and come out of their silos. We need to use that momentum to create a strong city. The next disaster will not necessarily be a flood – it could also be a tsunami, or a typhoon, or terrorism. Chennai needs to be prepared to face any disaster.”