Come, see our frothing, poisoned lake!

Humongous amounts of industrial effluents and sewage have been flowing into Bellandur Lake for at least two decades. Who is responsible for poisoning this once clean and beautiful lake? Who has been held accountable so far? What is the government doing to clean up the lake?

The contamination of Bellandur lake, the city’s biggest lake, which is now filthy and spewing fire and foam, is a crying shame and a big blot on the copybook of Bengaluru’s ecological record. The state government hasn’t kept its promise to clean up Bellandur lake. Granted, it’s a daunting task as the 3.61 square kilometer stretch has been violated by industries and thousands of apartment complexes, letting in chemicals and sewage.  

The grim prognosis is that the residents in and around Bellandur will have to put up with another two years of obnoxious odour emanating from the Bellandur lake. Minister Ramalinga Reddy says that the government is building a 350 MLD capacity Sewage Treatment Plant (STP) that will solve the problem of sewage getting into the lake.

Meanwhile, Bellandur Lake, once a beautiful green paradise of tranquil coolness, has turned into a hub of toxic froth. Untreated sewage from apartments and industries, has been flowing into the lake, primarily from HAL, Domlur, Kormangala and Agara.

Alarmingly, the toxic froth has been spilling on to the road, upsetting  commuters and disturbing them with the  smell. Residents have been demanding that the authorities stop sewage inflow into the lake and take up cleaning on a priority basis.

Chairperson of BWSSB Vijay Bhaskar says, “We have taken up spraying on a short-term basis so that the foam reduces. This could prevent the foam spilling on the road. We have also tried putting up a mesh, which has been destroyed by miscreants. For the long term, we have prepared a Lake Development Plan for Bellandur of Rs 194 crore. This will produce two results: first, it will create a diversion channel for the sewage to deviate from the lake; second, it will  desilt and rejuvenate the lake. As for the Sewage Treatment Plant, around 600 MLD of sewage water is diverted into the lake, of which 282 MLD is treated. We are making provisions to treat the rest of it and put the STP in place once the government approves.”

Currently, the authorities have installed about 4-6 machines near the lake to spray a chemical which the civic agency claim is a product of Japanese Technology and helps to subside the smell and the froth. However, it has been of little help, claim residents.  

Blaming the BWSSB, MP, PC Mohan says, “BWSSB should have taken up the work. We need to first put a stop to the sewage. For that BWSSB should check how many STP’s are working at present  and how many are required. The pollution control board needs to check the pollution levels. MLA Arvind Limbavalli and I have discussed all these issues in a meeting.”

Rahul Kanwar, a resident, questions, “How many visits and inspections does it take to do something about the lake? It is a prima facie case of sewage discharge, so they just need to make a plan, put up a Sewage Treatment Plant (STP) and simultaneously clean the lake.”

Kabir Das, another resident, adds bitterly, “Nothing has changed in the last five years. We have been infected with skin, asthma and wheezing problems. But does anyone care?” Despite innumerable inspections by officials, ministers and bureaucrats, life has not changed for the better for those living in the vicinity of Bellandur Lake.

Despite this the authorities continue to conduct inspections and have meetings, without following them up with action.

It can be cleaned up: IISc scientist

IISc scientist TV Ramachandran, who has made an extensive study of the lakes of Bengaluru Urban District, has suggested myriad solutions to save Bellandur Lake.  

Lakes in Bengaluru are interconnected. There are three valleys and Koramangala-Challaghatta-Bellandur-Varthur Valley is one of them (Figure 2.1). The Varthur Lake series belongs to the Koramangala Challaghatta Valley, consisting of Byappanahalli, Harlur, Kasavanahalli, Kaikondanahalli, Doddanakundi, Vibuthipura, Kundalahalli, Chinnappanahalli, Bellandur, Agara and Varthur Lakes.

In a study conducted by Energy and Wetlands Group Research Centre for Ecological Sciences, Indian Institute of Science, which was headed by TV Ramachandran, points out that Varthur lake is the second largest lake in Bangalore. It is a part of a system of interconnected tanks and canals, i.e. three chains of lakes, upstream, join Bellandur lake with a catchment  area of about 148 square kilometres (14979 Hectares). Overflow from this lake gets into Varthur lake and from there it flows down the plateau and joins Pinakini river basin.

So, Varthur Lake receives all the surface runoff, waste water and sewage from the Bangalore South taluk. The pollution levels have increased beyond the lake’s assimilative capacity. The study states that nutrient enrichment and profuse growth of macrophytes and algae have  occurred, which lead to reduced oxygen levels and threaten the aquatic life. A decline in ecosystem goods and services is also evident, from the adverse effect on economic growth and the livelihood of local people. Which is why, the Varthur lake series has to be restored to maintain and improve the quality of life of local residents of the Varthur lake area.

This series receives about 500 MLD (million liters per day) of untreated and partially treated sewage, daily. Sustained inflow of untreated sewage (due to BWSSB) and effluents (from industries) has contaminated the lake as the inflow of pollutants has surpassed the lake’s assimilative capacity. Froth formation at outlets, profuse growth and spread of macrophytes are all the indicators of nutrient enrichment. Nutrients in the form of N (nitrogen), carbon (C) and P (phosphorous) enter the lake through untreated sewage.

The major part of N is taken by plants and algae while phosphorous and carbon gets trapped in sediments. Due to high velocity wind, coupled with high intensity of rainfall, there are upwelling of sediments with the churning of water as it travels from higher elevation to lower elevation, in the process forming froth due to phosphorous. Discharge of untreated effluents (rich in hydro carbon) with accidental fire (like throwing cigarettes, beedis) has led to the fires in the lake.

Residents’ long battle

All along, lakeside residents have put up a brave front. From bearing the stench to getting treated for respiratory and allergic illnesses caused by pollution, they have suffered unceasingly. Monil JR, a resident near Bellandur Lake, points out, “There are times when we find it difficult to breathe. We often get headaches. We do not even open the windows of our homes. The paint on our houses has discoloured and even the silver in our homes has changed. It is slowly turning black.”

In their fight against polluters, the residents of Yemlur, Bellandur and Varthur are creating awareness by holding talks in the neigbourhood and on  social media. In fact, many citizens are coming together to plan a massive strike in the coming days. On Monday, the residents met Union Health Minister JP Nadda to petition him on the issue.

10 Steps to a clean Bellandur Lake

• De-silting: Due to sustained inflow of sewage and effluents, lake sediments are contaminated (with heavy metal, etc.). De-silting and technological advancements will allow wet dredging in a lake. Removal of accumulated silt will help in the storage of rain water and also recharging of ground water resources in the vicinity. This is essential as the groundwater table in the vicinity is as high as 1000-1500 feet.
• Treatment of waste water through constructed wetlands and algae ponds. Constructed wetlands with shallow algae ponds helps in the removal of nutrients.
• Allowing only treated wastewater (sewage and effluents) into the lake.
• Re-establishing interconnectivity among lakes: Removal of all encroachments (of storm water drains and Raja Kaluves). Encroachments of storm water drains has led to stagnation of water and flooding in Yamalur region.
• Ban on alterations in the topography. Due to large-scale land use, changes and filling of low lying area, some of the new localities are now vulnerable to floods.
• Removal of all encroachments in the lake bed: We need to show mercy to our next generation and evict all types of encroachers.
• Re-establishing wetlands at the inlets of these lakes: Bellandur lake on either side (inlet as well as at outlets) had large spatial extent wetlands, which have been and are being encroached upon by land mafia. These encroachments have to be removed immediately to ensure successful lake restoration and ensure water security in the region.
• Maintaining a 30 m buffer around the lake (with regulated activities), will also help to a large extent.
• Stoppage of dumping of solid waste and disposal of liquid waste by tankers.
• Constituting a lake conservation committee consisting of all stakeholders for regular monitoring and management.
• Putting a threshold on high-rise buildings in the region. There is also a need to protect valley zones, considering ecological functions.

Rejuvenation is meaningful only when all interconnected lakes in the series are restored, otherwise Bellandur and Varthur lake will continue to face contamination due to polluted lakes in the upstream.

Create a task force

Experts have been pressurizing the authorities to create a specific team working with a time-bound plan for overall lake revival. Ravi Mishra points out, “I think we should shift the ownership. In principle, the BWSSB chairman has accepted that it is their responsibility to clean the lake. Recently, the CM said BBMP would take up the issue. This is just to confuse the people. In fact, we should stop calling them lakes. They are now ponds with sewage that needs to be restored. There is no water in them, just sewage and sewage is the subject matter of the BWSSB. BBMP created a DPR in 2009, then handed over to BDA and so on.”