The CAG report had referred to the 2015 Chennai floods as a man-made disaster. On a contradicting note, the same city of Chennai is now in the midst of water scarcity crisis.

Urbanisation is taking place at a faster rate in India. Population residing in urban areas in India crossed 30% as per 2011 census, standing at 31.16%.

According to the Composite Water Management Index (CWMI) report released by the NITI Aayog in 2018, 21 major cities (Delhi, Bengaluru, Chennai, Hyderabad and others) are racing to reach zero groundwater levels by 2020, affecting access for 100 million people.

Urbanisation affecting Waterbodies:

Exploitation of Ground water:

• We need to also realise that with the country’s rapid urbanisation, demand cannot be met by groundwater reserves alone.
• For instance, according to the Delhi Jal Board estimates, groundwater meets just 10% of Delhi’s drinking water needs. The rest is met by surface water sources, most of it transported from outside Delhi.

Encroachment

• In Bengaluru, 15 lakes have lost their ecological character in less than five years according to a High Court notice to the city’s administrative body responsible for civic amenities and some infrastructural assets.

Pollution

• There is an increasing level of urban population which however is not having enough civic facilities such as adequate infrastructure for the disposal of waste. Therefore, lakes become the dumping grounds for disposing untreated local sewage and solid waste.

Eutrophication:

• Lakes are closed water bodies. Therefore, a large part of the substances that enter in the lakes become a permanent part of it. There is a rapid change in the in the lakes which leads to growth of unwanted weeds destroying ecology of the lakes.

Unplanned Tourism Activities

• There is unplanned tourism activities as there is no systematic planning and regulation. There is no adequate facility to dump garbage which leads to lakes becoming dumping grounds. Therefore, adequate arrangements for sustainable tourism must be made in cities like Udaipur which is filled with lakes, Dal Lake in Srinagar, etc.

Implications:

Water Quality

• Research within India revealed the scale of urbanisation impacts in Hyderabad, where the number of waterbodies has fallen dramatically. Lakes in Hyderabad were also found to have fluoride concentrations exceeding maximum permissible limits set by the Bureau of Indian Standards and World Health Organization.
• Fresh Water Watch measurements identified key links between the nutrient concentration and inputs of raw sewage, domestic waste and industrial effluents.

Urban floods: 

• Improper and Inefficient Urbanisation is the primary cause for the floods in urban areas, especially in metros. For instance, failure of the drainage system is believed to be one of the primary causes behind the Chennai floods in December 2015 that led to the death of more than 400 people.

Water Crisis

• Cooum, Buckingham canal and Adayar are the three rivers that runs through the chennai city, all are dried up and dead due to industrial wastes and lack of civic measures.
• These coupled with Over exploitation of ground waters are turning cities into Dry and Dead cities in near future.

Solution – Mitigation & Rehabilitation

• Cities need to stop the destruction of local water bodies and local tree cover, treat its sewage properly, harvest rainwater, and stop straightening and concretizing the rivers and encroaching on their floodplain.

• Mission Kakatiya Model: Mission Kakatiya of Telangana involves the restoration of irrigation tanks and lakes/minor irrigation sources built by the Kakatiya dynasty.

• Reclaiming of Kundalahalli Lake: Kundalahalli lake in Bengaluru which had made way for a landfill has been reclaimed through corporate social responsibility funds in a Public-Private Partnership model.

• Mapping of the flood prone areas is a primary step involved in reducing the risk of the region. Historical records give the indication of the flood inundation areas and the period of occurrence and the extent of the coverage.
• Enacting the Flood Plain Zoning Bill in states
• The number of casualties is related to the population in the area at risk. Hence, in areas where people already have built their settlements, measures should be taken to relocate to better sites so as to reduce vulnerability.
• No major development should be permitted in the areas which are subjected to high flooding. Important facilities like hospitals, schools should be built in safe areas. In urban areas, water holding areas can be created like ponds, lakes or low-lying areas.
• Better coordination among the government agencies which undertake lake and wetlands restoration and protection programmes
• With the help of reforestation, protection of vegetation, clearing of debris from streams and other water holding areas, conservation of ponds and lakes etc. the amount of runoff can be decreased.

It is estimated that in just 30 years from now, by 2050, half of India will be living in cities. The Chennai crisis is not an alarm, but it is an explosion signalling to wake up or else humanity would be facing the consequences of nature wreaking great havoc on humanity.