URBAN FLOODSFloods are a natural process and are the most common of all-natural disasters. A flood is an overflow of water that submerges land that is usually dry. One of the highly flood-prone countries in the world is India. Urban flooding is one of the types of flood. Urban flooding is the inundation of property in more densely populated areas caused by rainfall and sometimes triggered by events such as flash flooding or snowmelt. Urban flooding is a condition that has repetitive impacts on communities. Urban areas are densely populated and people living in vulnerable areas suffer due to flooding. It is not only the event of flooding but the secondary effect of exposure to infection also has its toll in terms of human suffering. In urban areas, existing paved streets and roads exacerbated the flood effects. In urbanized areas, the flood flow constitutes a hazard to both the population and infrastructure. Some recent catastrophes worldwide include: The flooding of New Orleans (USA) in 2005, the inundations of Nîmes (France) in 1998 and Vaison-la-Romaine (France) in 1992, and the flooding in Rockhampton, Bundaberg, Brisbane during the 2010–2011 summer in Queensland (Australia). In India, Recent events of urban floods include 2013 Uttarakhand floods due to could burst, Chennai deluge;floods in Assam and Madhya Pradesh in 2016 and Kashmir deluge due to torrential rainfall; 2015.
There has been an increasing trend of urban flood disasters in India and the most notable amongst them are Hyderabad in 2000, Ahmedabad in 2001, Delhi in 2002 and 2003, Chennai in 2004, Mumbai in 2005, Surat in 2006, Kolkata in 2007, Jamshedpur in 2008, Delhi in 2009 and Guwahati and Delhi in 2010.Causes: Causes of urban flooding can be man-made and natural. Some of the Natural causes are as follows: Cyclone making landfalls in coastal areas, change in river course, excessive rainfall, etc. Man-made causes are as follows:
- More migration causes reduced availability of land and it finally leads to more encroachment of water bodies.
- Disposal of waste results in waste clogging the natural channels and stormwater drains.
- Misuse of water bodies.
- Illegal mining activities and Illegal construction have an extremely damaging impact on the water body.
- Sudden release or failure to release water from dams can also have a severe impact.
- The badly planned construction of bridges, roads, railway tracts causes drainage congestion.
- Unplanned release of water from dams and unplanned tourism activities
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- Absence of drainage and stormwater network in many places.
- Rapid urbanization causes permeable soil surfaces being replaced by impermeable concrete floors leads to urban flooding.
- Increase in urban rainfall extremes and temperature.
- Population explosion: According to the Census 2011 data, there are now more than 300 cities in India. Three of the world’s 10 largest cities, Delhi, Mumbai and Kolkata, as well as three of the world’s fastest-growing cities, Ghaziabad, Surat and Faridabad, are in India. It’s no wonder that the flooding in haphazardly growing cities like Ghaziabad and Surat is even worse.
Effects of urban flooding
EXAMPLES OF INDIAN CITIES (smudged by knee-deep water): MUMBAI: Mumbai is India’s shining commercial capital. A few hours of rain and the shine is smudged by knee-deep water. Reasons for flooding in Mumbai:
- Damage to vital infrastructure, loss of life and property.
- Disruption in transport and power and incidence of epidemics, loss of livelihood.
- Urban flooding cause localized incidents to major incidents, resulting in cities being inundated from hours to several days.
- Deterioration of water quality and risk of epidemics.
- Temporary relocation of people, damage to civic amenities.
Read also: Anthropocene Working Group (AWG) Voted In Favour Of Anthropocene Epoch In Bengaluru, some of the reasons for flooding are rapid, unplanned urban expansion, few lakes. Reasons for flood in Chennai. The degradation of Ennore creek, and the constant draining of the Pallikaranai marshes, unscientific urbanization and expansion of Chennai city. Marshy land converted to concrete infrastructure that worsened the condition, poor urban planning. Unplanned waterbodies and mindless urban expansion. Chandigarh went underwater due to population expansion In July 2018, Bhubaneswar went underwater due to extreme rainfall. Sudden release or failure to release water from dams can also have a severe impact.
- Mithi river has been encroached upon over the years and is left clogged with solid wastes and plastic.
- Urbanization, inefficient network of surface drains, underground drains and canals,
- Mangroves have largely disappeared. The above-ground roots of mangroves slow down water flows, encourage deposition of sediments.
What needs to be done:Floods in India are an outcome of both natural and anthropocentric changes. However, the man-made changes have been more responsible for floods to a large extent. Thus comprehensive urban planning is required. Some of the actions we can take are as follows:
- Create flood plains and overflow areas for rivers and separating rainwater from the sewer system.
- Install water infiltration and attenuation systems, Sustainable drainage: permeable pavement, sidewalks, and gardens.
- Strong laws should be in place to protect urban lakes the water bodies.
- The catchment and feeder channels need to be protected.
- There is a need to set up an umbrella authority to protect and conserve the water bodies.
- Funds should be provided for water supply to only those cities that have brought their own water sources under protection.
CONCLUSION:India is at the crossroads of an urban transformation. We need to avoid flooding in a sustainable manner. It becomes very important at the present time to pay immediate attention to more prudent urban planning before it’s too late. Rather than only providing engineering solutions. Urban planning should be ecology and people-centric. Source Read Also: Vayu no longer a cyclone, to cross as low pressure By 2027, India population to cross China’s: UN