Urbanisation

Two sides of the same coin: Shrinking water bodies and urban floods

Water bodies have become even more critical in current times when cities are facing the challenge of rapid, unplanned urbanisation

 
By DTE Staff
Published: Friday 07 August 2020
Shrinking water bodies push urban floods
A railway track cuts through Guwahati’s Deepor beel, one of the most encroached water bodies in Assam. Photo: Mudit Mishra A railway track cuts through Guwahati’s Deepor beel, one of the most encroached water bodies in Assam. Photo: Mudit Mishra

Lakes and wetlands are an important part of urban ecosystem. They perform significant environmental, social and economic functions — from being a source of drinking water and recharging groundwater to supporting biodiversity and providing livelihoods.

Their role becomes even more critical in the present context, when cities are facing the challenge of rapid unplanned urbanisation.

Their numbers are declining rapidly. For example, Bangalore had 262 lakes in the 1960s; now only 10 of them hold water. At least 137 lakes were listed in Ahmedabad in 2001; construction work started on 65 of them.

Another example exhibiting this increasing loss of urban water bodies is Hyderabad. In the last 12 years, Hyderabad has lost 3,245 hectares of its wetlands.

Concretisation has been a major problem in several cities and towns, according to The National Disaster Management Guidelines: Management of Urban Flooding report, published by the National Disaster Management Authority (NDMA) in 2010.

According to the Union Ministry of Urban Development (MoUD), 31 per cent of the country was urbanised in 2011. The ministry says almost 50 per cent of the country will be urbanised by 2050.

MoUD data also suggests a 54 per cent increase in the number of cities and towns between 2001 and 2011.

Natural streams and watercourses, formed over thousands of years due to the forces of flowing water in the respective watersheds, have been altered because of urbanisation.

“As a result, the flow of water has increased in proportion to the urbanisation of watersheds. Ideally, natural drains should have been widened to accommodate the higher flows of stormwater.

But, on the contrary, there have been large scale encroachments on the natural drains and the river flood plains. Consequently, the capacity of natural drains has decreased, resulting in flooding,” said the NDMA report.

Urban water bodies have been a victim of unplanned urbanisation in India, because of which they face several threats such as encroachment, disposal of sewage, groundwater decline leading to fall in the level of water, unplanned tourism and absence of administrative framework. Let us discuss these in detail:

Pollution: There has been an explosive increase in the urban population without corresponding expansion of civic facilities such as infrastructure for the disposal of waste.

As more people are migrating to cities, the urban civic services are becoming less adequate. As a result, most urban water bodies in India are suffering because of pollution.

The water bodies have been turned into landfills in several cases. Guwahati’s Deepor beel, for example, is used by the municipal corporation to dump solid waste since 2006. Even the Pallikarni marshland in Chennai is used for solid waste dumping.

Adding to the sorry state of urban water bodies is the misuse by local communities for their cultural or religious festivals such the immersion of idols. Heavy metal concentration can be found in lakes in Nagpur and Bhopal and the Hussainsagar Lake in Hyderabad after idol immersion every year.

Sources: Research articles and documents; personal communication with government officials and researchers; newspaper articles

Encroachment: This is another major threat to urban water bodies. As more people have been migrating to cities, availability of land has been getting scarce.

Today, even a small piece of land in urban areas has a high economic value. These urban water bodies are not only acknowledged for their ecosystem services, but for their real estate value was well. Charkop Lake in Maharashtra, Ousteri Lake in Puducherry, Deepor beel in Guwahati are well-known examples of water bodies that were encroached.

Another interesting example of encroachment and pollution, not by some private builder but the government itself, is Pallikarni marshland in Chennai.

The size of this city wetland has been decreasing rapidly. Once a bird sanctuary, it is now the dumping yard of the city: Dumping of solid waste, sewage discharge and construction of railway stations and roads have shrunk this wetland.

Another example of government encroachment is Sola beel in Guwahati; the state revenue department allotted the lake bed for construction, in spite of Gauhati High Court’s order to protect all wetlands in the state.

Illegal mining activities: Illegal mining for building material such as sand and quartzite on the catchment and bed of the lake have extremely damaging impact on the water body.

For example, the Jaisamand Lake in Jodhpur, once the only source of drinking water for the city, has been suffering from illegal mining in the catchment area for the last 20 years despite a court order to stop mining in 1999.

Badkhal Lake in Faridabad has dried up in the same way. Unmindful sand mining from the catchment of Vembanad Lake on the outskirts of Kochi has decreased the water level in the lake.

Unplanned tourism activities: Using water bodies to attract tourists has become a threat to several urban lakes in India. Tso Morari and Pongsho lakes in Ladakh have become polluted because of unplanned and unregulated tourism.

Another example is that of Ashtamudi Lake in Kerala’s Kollam city, which has become polluted due to spillage of oil from motor boats.

Absence of administrative framework: The biggest challenge is the government apathy towards water bodies. This can be understood from the fact that the it does not even have any data on the total number of urban water bodies in the country.

A few cities that recorded the number of water bodies did so because of court rulings.

A 2010-11 Comptroller and Auditor General of India report on the plight of 22 lakes in 14 states said:

The Union Ministry of Environment & Climate Change (MoEF&CC) had not identified wetlands associated with each river / lake and no identifications of risks to these wetlands due to pollution of river water / lake water had been carried out by the Central Pollution Control Board (CPCB).

Further, CPCB had not identified major aquatic species, birds, plants and animals that faced threat due to pollution of rivers and lakes.

The book highlights how the above reasons have led to the depletion of water bodies in urban areas. It also highlights the need for immediate action to conserve and revive our water bodies.

India is urbanising at a phenomenal rate (433 million people will be in living in urban areas by 2021). This can only be sustained with its water bodies.

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