In mid-February, the biggest lake in the city of Bangalore, India, caught fire and kept on burning for 12 hours, leaving behind a black air patch and a bunch of terrified fire fighters wondering how this could have happened in the first place. It is the second time Bellandur Lake is reported burning, and there is no need for a third one for scientists to be convinced that India’s once upon a time “Silicon Valley” will become unliveable in ten years from now.
A lethal combination of factors creates an environment that merely requires the slightest of triggers for lakes to go up in flames. Untreated effluents pour into the waters from the many industries and homes on its banks, illegal waste disposal takes place on a large scale – often including rubbish which is set on fire – and invasive weeds cover large swathes of the lake in a thick green canopy.
The Energy and Wetlands Research Group at the Indian Institute of Science (IISc) explains that an estimated 400-600 million litres of untreated sewage is let into the lake catchment every day, creating a toxic environment fertile for disasters like the fires and foam. An anaerobic thick layer is formed in the water below the lake’s surface, where methane is formed. It is obvious that the cause is untreated sewage led into the lake by the city’s water supply.
Long before it began its slow and painful death, Bellandur Lake was part of a clever water and irrigation system devised by the founders of Bangalore in the 1600s, giving it the “city of lakes” moniker. The streams formed at the top of surrounding valleys were dammed into man-made lakes by constructing bunds. Each of these lakes would harvest rainwater from its catchments and the surplus would flow downstream, spilling into the next lake in the cascade via storm water drains or raja kaluves. The bodies of water would in turn serve the needs of the population. In the 1970s, there were still 285 lakes in the city, making it self-sufficient in its water needs. Today, however, there are just 194 lakes, and the large majority of them are sewage-fed. The rest, according to The Guardian, have been lost to encroachments – by the Bangalore Development Authority, private real estate developers and illegal builders – to cater to the booming housing needs of a city of 10 million people.
Rapid and unplanned urbanisation between 1973 and 2016 caused a 1005% increase in paved surfaces and decline of 88% in the city’s vegetation, while water bodies declined by 85% between 2000 and 2014. Urban expansion was the result of the quick rise of the IT sector, causing the city to attract lots of software companies, thousands of IT professionals and, obviously, waves of unemployed citizens. This also explains Bangalore’s increasing production of e-waste, reported at 20,000 tonnes per year. E-waste production and recycling in India has been a major problem; 90% of it is dealt with through the informal sector, which is harder to monitor.
Unaware of the necessary safety measures, some incinerate the e-waste, releasing lead, mercury and other toxins into the air – and dump the rest, allowing pollutants to infiltrate the groundwater. Latest studies show that e-waste concentration in Indian soil is twice the global average. Researchers said informal recycling of e-waste, open burning of dumped solid waste, combustion of coal and industrial waste plus ship breaking activities acts as a sink for heavy chlorine compounds. These are persistent pollutants able to stay in the environment for longer periods, get dispersed over long distances, and accumulate in the fatty tissue of humans, land and marine animals. Long term exposure on humans can cause certain cancers, birth defects, damage the central nervous system, immune and reproductive systems, and can affect the food chain.
The water pollution in Bangalore poses a serious threat to residents’ health and creates a chronic shortage of clean water or even air, given that lung-related medical conditions have drastically increased in the city lately with a vegetation cover of a mere 3%. All in all, experts predict a severe water crisis which will make Bangalore uninhabitable by 2025, with residents potentially having to be evacuated.
The incident highlights, once again, the urgent need for a global campaign for proper waste management, especially in the developing world, as a key-measure to protect public health and advance in the Sustainability Development Goals. ISWA invites everyone to join the campaign for closing the world’s dumpsites. You can find different ways of involvement in this project here. For more you can visit ISWA’s new website http://closedumpsites.iswa.org and, at least, sign the declaration that calls for a global coordination against the risks of dumpsites.