Bellandur-Varthur lake rejuvenation is causing irreversible damage, need course correction, say environmentalists

Environmentalists, in an open letter to the government, pointed out that draining and desilting the toxic Bellandur and Varthur lakes would have severe impacts. They urge the government to hold an Environment Impact Assessment beforehand

As the rejuvenation of Bellandur and Varthur lakes is underway, the NGO Bangalore Environment Trust (BET) has written an open letter to the state government, requesting course correction. The expert committee on lake rejuvenation had recommended that both the lakes be desilted, but BET’s letter points out that it’d take 53 years to remove the toxic silt-cum-slush in Bellandur lakebed, and 20 years for Varthur lakebed!

This is because toxic waste has flown into the two lakes, unimpeded, for the last 50 years. BET’s calculations are based on a recent study by the Indian Institute of Science (IISc).

More importantly, the letter points out that as part of rejuvenation, about 500 million litres of toxic wastewater entering Bellandur lake has been diverted to Varthur lake. And the water would be further diverted to Dakshina Pinakini river. This would affect several water bodies downstream of Bellandur lake, and the residents there, the letter says.

BET is headed by environmentalist and ex-IFS officer A N Yellappa Reddy. Other signatories to the open letter include Dr S Ravichandra Reddy, expert member of the NGT-appointed committee for Challakere lake, Dr Rajmohan, former member of the State Environmental Impact Assessment Authority, Dr Harini Nagendra, Professor of Sustainability at Azim Premji University, and so on.

The letter urges the government “to pause the current activities, carry out an EIA (Environmental Impact Assessment), develop a multi-disciplinary comprehensive action plan for the lake ecosystem.”

Following is the open letter:

BET and Citizen experts’ feedback on rejuvenation of Bellandur and Varthur lake

Dear Sir/Madam,
We are very glad that Karnataka Government is working hard under the ambit of NGT to rejuvenate Bellandur and Varthur Lake. While we wholeheartedly thank you, for all your efforts to save the lake, we would also like to join hands with you.

We are putting forth some feedback on the process of rejuvenation. By doing that, we sincerely hope that the government will pause to assess the effectiveness of the actions taken so far and adjust future actions, in collaboration with citizens.


1. Translocating toxic pollution to downstream waterbodies:

  • The rejuvenation approach of diverting approx. 500 Million Litres of toxic wastewaters entering Bellandur Lake, to Varthur Lake and subsequently to Dakshina Pinakini river, seems to us that the polluting matter is being pushed downstream, thus translocating pollution.
  • If the objective is pollution abatement, then diversion work is in contradiction to that objective, as it allows the toxic wastewater to travel long distances and thus increase the pollution load of the waterbodies downstream. Rejuvenation of one waterbody should not spell a death knell to other water bodies. This activity is in contravention to Section 24 of Water Act. According to our constitution, people downstream of Bellandur Tank also have the right to clean and healthy environment.
  • Bellandur Tank wastewater has already been diverted to Varthur Lake. Varthur Lake diversion is in the works. We request the government to pause, validate the approach via an EIA and make the necessary course correction.

2. The case of desilting:

  • For the past 50 years, both Bellandur and Varthur lakes have been the recipient of municipal solid waste, industrial solid waste, construction and demolition, hospital waste, plastics, raw sewage, toxic industrial effluents and silt – a toxic cocktail. Hence based on precautionary principle, one can deduce that 19.4 million tonnes of Silt+Slush (SS) cocktail on Bellandur lakebed and 7.8 million tonnes of SS cocktail on Varthur lakebed is hazardous in nature, both biologically and chemically.
  • The expert committee, in its submission to NGT, recommended that the lakes be de-silted to the original lakebed. That is to remove 19.4+7.8 million tonnes. De-silting this humongous quantity is a daunting task.
    • The quantum of SS cocktail accumulated on the Bellandur lakebed is equivalent to the quantum of garbage Bangalore would take 10.5 years to generate. (@ the rate of 5000 tonnes/day that Bengaluru generates today).
    • The quantum of ss cocktail accumulated on the Varthur lakebed is equivalent to the quantum of garbage Bangalore would take 4 years to generate.
    • Mavallipuram landfill had close to 4 million tonnes of garbage before it was closed. The quantity of toxic cocktail in Bellandur lakebed is 4.8 times more than what is in Mavallipuram and for Varthur lake it is 1.8 times more. In this context, de-silting seems like translocating a landfill or a lakefill, in this case.
  • To practically de-silt, such huge quantities will take a long time. Even if we can remove 1000 tonnes per day, it will still take 53 years to completely de-silt Bellandur lakebed. It will take 20 years to de-silt Varthur lakebed. What about traffic, road wear and tear and air pollution and the related health hazards as the heavy trucks move in and out of these congested roads?
  • If the de-silting were to be carried out for a year, then only 1.8% of the total toxic cocktail on Bellandur lakebed and 4.9% on Varthur lakebed would have been removed. This is at a huge cost of hundreds of crores of rupees. Currently, 300 crores is allocated for de silting Bellandur lake alone. Compare that with 9.23 crores allotted to Bellanduru ward. What measurable benefits are obtained from this expensive activity? Can the cost justify the benefits? Does the economics work out?
  • Where will the toxic cocktail go? Is it safe to be given to the farmers? Have the farmers been informed of the risk and the precautions they need to take? Our constitution provides the same right to clean and healthy environment to farmers as well. The produce they grow with such toxic inputs will come back on our food plate. Then comes the question of food safety and risk to public health.
  • Can the toxic cocktail be sent to quarries? We in Bengaluru have no place to put our garbage and suffer from a perennial garbage crisis. In that context, is there enough space to dump this toxic cocktail elsewhere?

3. Environmental Impact Assessment:

The current measures of Diversion and De-silting are in-fact translocating polluting matter with significant and irreversible environmental impact. Such changes require an Environmental Impact Assessment (EIA) including cost benefit analysis. EIA has a special place in environmentally sound management of lake ecosystems. This will ensure a level playing field and remove arbitrariness in decision making process.

4. Stop Pollution at Source:

Lakes are by no means independent of the surrounding land systems. The pollution of the lake ecosystem is directly related to the activity in the catchment area upstream. The lake is just the receiving waterbody. Any interventions to overcome pollution must be targeted upstream where the wastewater is generated. The thumb rule of pollution prevention is “stop pollution at source”. Enforcement programs for pollution prevention is a continuous activity and is cheaper than clean-up afterwards.

5. Develop Lake Ecosystem Management Program:

  • A one-time capital-intensive engineering and infrastructure activity like diversion, de-silting and building sewage treatment plants, is NOT the panacea for mitigating complex pollution problems.
  • To restore and maintain the chemical, physical, and biological integrity of the Lake ecosystem, a Lake Ecosystem Management Program must be developed. This program must be rooted in science with quality water data, clearly defined goals and measurable objectives aligned with financial resources.
  • This can be notified and operationalised by the state government under section 3.(3) of Environment Protection Act of 1986, as recommended by government’s own report, “Expert Committee Report on Rejuvenation of Bellandur Lake” under the Chairmanship of Additional Chief Secretary, Sri Mahendra Jain, IAS.

Improving the health of the lake ecosystem is a gradual and continuous process. We, the citizens, are with the government in restoring the waterbody. In the light of ecological fairness and justice, we request you to pause the current activities, carry out an EIA, develop a multi-disciplinary comprehensive action plan for the lake ecosystem and make the necessary course corrections. We kindly request you to give due consideration to our comments.

The entire letter, along with details of the IISc study, can be viewed here.


  1. Varadarajan raman says:

    It should shock all of us what thoughtless and reckless damage to lakes over very many years can do! Rejuvenation or reversing of accumulated damage becomes such a monumental problem. The process is both slow and hugely expensive. This is not just with lakes but also with air pollution. Taken together with the barely 3% green cover in Bengaluru and depleting ground water, it is time to acknowledge that we face a near Environment Emergency. Only then, can we put in place a planning mechanism capable of responding to this emergency. For this, the Government must bring in expertise from individuals and institutions such as the IISc. Nothing can be more important and urgent.

  2. Professor K S Bhat says:

    While the letter high lights the gravity of the task of desilting these two lakes and near impossible time frame,the suggestion to pause the operations pending more studies is not welcome.The problem of 500 MLD OF SEWAGE flow needs to be tackled by expediting the upstream STPs on the one hand and permanently stopping the cocktail of sewage by treating them at source or in upstream lake series.I hope the arrangement of diversion is only a temporary measure till the STPs become operational and silting is completed in a realistic time frame.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Similar Story

For home-buyers in Bengaluru, a checklist to assess water security

Here is a comprehensive list of the critical questions to ask about water systems and availability, when buying a home in Bengaluru.

Sneha (name changed) decided to buy a flat in a gated community in Bengaluru this year. She was worried about the availability and sufficiency of water supply. She ticked off her checklist by asking one question to the builder: “How many borewells are there?” But could she have done more to assess water security in her new home? “Beyond that one question on borewells, no one could ask anything more,” she says, adding: “It is hypothetical, whether these borewells would supply the required water. Everyone felt that the use of tankers was inevitable. And that eventually the government would solve…

Similar Story

Water crisis 2024: Bengaluru parched, but cities across India struggling too

A round up of urban water crisis this summer, Bengaluru being the worst affected, and how governments are dealing with it.

With India witnessing one of the most scorching summers, water crisis is looming across many cities in the country. India's main reservoirs have hit their lowest March levels in five years, according to government data, indicating a strain on drinking water and power availability this summer. As per Central Water Commission (CWC) data, the 150 reservoirs monitored by the central government, which supply water for drinking and irrigation and are the country's key source of hydroelectricity, were filled to just 40% of capacity in March 2024.  India's hydro generation in the last 10 months from last April is down by…