Context: The need to reduce the burden on Chennai’s water resources by diversifying other urban centers.

Tamil Nadu Fact sheet:

  • Tamil Nadu constitutes 4 percent of India’s land area and is inhabited by 6 percent of India’s population, but has only 2.5 percent of India’s water resources.
  • In 2001, Chennai’s water requirement stood at 1,327 million litres per day (MLD).
  • The supply was only 830 MLD in 2018.
  • By 2021 the demand will shoot up to 1,980 MLD.
  • The area coming under city limits that was just 176 sq. km in 1978 has increased nearly threefold, to 425 sq. km, today.

Reasons for such a water crisis in Tamil Nadu:

  • Skewed Chennai-centric development model of Tamil Nadu has resulted into the capital city’s water demand overshooting its available water resources.
  • Over 60% of the rainfall that Tamil Nadu receives is from the northeast monsoon also known as the retreating monsoon. However, repeated failure of northeast monsoon has resulted in acute water shortage in the city.
  • The demand for water in Tamil Nadu is increasing at a fast rate both due to increasing population and also due to larger per capita needs triggered by economic growth. The per capita availability of water resources however, is just 900 cubic meters when compared to the national average of 2,200 cubic meters. 
  • Agriculture is the largest consumer of water in the State using 75 per cent of the State’s water resources.
  • The biggest issue which highlights the policy paralysis of the city administration is the development of the IT Corridor. Although the infrastructure and space were provided to them, not once did they think about the water supply which would be required to meet the demand. 

Possible solution to the water crisis problem in Chennai: The demand-supply asymmetry has rendered traditional solutions such as rainwater harvesting and groundwater recharge totally ineffective. Overcoming the crisis will, hence, require some unconventional solutions to be tried. Some of them are mentioned below as:

  • Chennai-centric development model of Tamil Nadu has created the water crisis situation in the city. Chennai can be decongested by developing other urban centers in the state.
  • The factors that attract people from across Tamil Nadu are prospects of better education, employment opportunities and possibilities of a decent lifestyle. These can be focused can accordingly investments can be made.
  • The districts of Cuddalore, Nagapattinam and Tiruchirappalli together receive an average rainfall of more than 1,200 mm per annum, compared to the 900 mm-1000 mm average annual rainfall of Chennai. Some of the major investments can be shifted to these areas.
  • Tamil Nadu can learn from the countries like The Netherlands and South Africa. Tamil Nadu can distribute its commercial and administrative wings across cities to reduce the burden of water demand on Chennai.
  • Tamil Nadu has a long Coastline of 900 km, yet the total installed capacity of its two desalination plants is only 200 MLD - the Minjur plant and the Nemmeli plant both possess a capacity of 100 MLD each. Saudi Arabia, the world leader in installed capacity of desalination plants, has built such plants all along its coastline and its largest plant, Ras-Al-Khair, has a capacity of 1,000 MLD. Tamil Nadu can also look forward to increase the capacity of its installed desalination plants and at the same time build such plants all along its coastline.
  • Tamil Nadu cultivates paddy in an area of about 18.3 lakh hectares, requiring about 710 thousand million cubic feet of water. A nominal shift away from paddy to less water-intensive but high-income crops such as pulses, vegetables, and ornamental plants would save fresh water.

Conclusion: The Niti Aayog Composite Water Management Index states, “54 percent of India’s groundwater wells are declining and 21 major cities are expected to run out of groundwater as soon as 2020, affecting approximately100 million people.” Without more storage and managing use, there is no real hope that we can build water resilience in our cities. It would be nice to optimise our use of resources. We can learn from countries like Israel that has powerful lever of building resilience in water management. They have their foundation (i.e, an understanding and appreciation of the climate and environmental systems and the services they provide that is central to human civilization) and building (i.e, stainably use and reuse, the resources and services the natural world provides) in place.

Source: https://www.thehindu.com/opinion/op-ed/balancing-tns-growth-model/article29086410.ece