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Bellandur's industrial woes

Last Updated 29 April 2017, 19:39 IST

For years, the pollution control officials were in denial mode: Domestic sewage, and not industrial effluents was what caused Bellandur lake’s decay, they declared. Going after polluting apartments was then their obvious response. But could the real big polluters, the industries big and small, get away so fast?

The National Green Tribunal (NGT)’s inspection of the lake offered the scientific community an opportunity for some course correction. Armed with telling lake sample study reports, they exposed how the deadly concoction of chemicals let out by industries had wrought unimaginable damage to the water body.

The extent of that chemical destruction convinced the Tribunal of the urgent need to arrest the decay. Its recent ruling, mandating the closure of all polluting industries in the lake’s vicinity, was a direct result of that scientific mediation.

Rejuvenation blueprint
The critical role played by industrial effluents in the foam and froth formation has been reinforced by a blueprint on the rejuvenation of the Bellandur and Varthur lakes, released recently by Dr T V Ramachandra and team from the Centre for Ecological Studies, Indian Institute of Science.

The blueprint notes that the loading of Phosphates in the lakes has led to nutrient enrichment for the cyano-bacterial blooms and macrophytes (aquatic plants). But surfactants such as sodium or ammonium laurets, found in huge quantities are equally responsible.

Industrial surfactants
Here’s the industrial linkage: “Surfactants are used by many industries as wetting agents, dispersants, defoamers, de-inkers, antistatic agents, and in paint and protective coatings, pesticides, leather processing, plastics and elastomer manufacturing, and oil extraction and production,” says the blueprint.

So, how does the frothing happen? “A portion of phosphates is up-taken by aquatic plants while the balance gets trapped in the sediments. Pre-monsoon showers coupled with gusty winds lead to the churning of lake water with upwelling of sediments. Vigorous mixing of surface water coupled with high flow across narrow channels leads to bubble formation that persist and build up as foam.”

Hydrocarbons
If the foam and frothing attracted nationwide media attention, the sight of fire on the lake sparked a public outcry. The blueprint had an explanation for the fire, again from an industrial perspective. It says: “Foam caught fire due to compounds with high flammability i.e. hydrocarbons and organic polymers that came from nearby industries in the vicinity of Bellandur lake.”

The implication was clear: Discharge of untreated effluents, rich in hydrocarbons, had sparked the accidental fire. The culprits were hundreds of micro, small and medium-scale industrial units related to garments, dyeing, leather tanning, laundry and automobile maintenance including garages.

KSPCB role
The Karnataka State Pollution Control Board (KSPCB) has been blamed for letting these industries go scotfree by not strictly monitoring their emissions. How did the industrial units manage to get the required licences in the first place, ask lake activists and environmentalists.  

If NGT has found the industries guilty, the next logical step would be to identify them and close them down. But there is a problem of vicinity. Locating hundreds of such units would be a tough task.
A vocal critic of the existing system, Bellandur resident Nagesh Aras had proposed crowd-sourcing the location of these industries besides garbage/construction debris dumping sites.

Bellandur lake receives about 447 Milliion Litres Daily (MLD) of untreated sewage, almost 40% of what the entire city generates in a day. As Aras points out, restricting the action on industries located within a kilometre or two around Bellandur lake will not make much impact.

The high use of phosphates in detergents for washing at an industrial scale has also been cited as a key factor in the foaming and frothing. Studies have shown that although use of detergents is going up unregulated, facilities for recovery of detergent constituents and treatment are extremely scarce.

Laws ignored
The Environment Protection Law of 1989 had stressed on the implications of detergents as a potential chemical pollutant on the surface and various receiving waters. Yet, they are being used relentlessly. Reports suggest a 1.5 fold decadal growth in the use of detergents.

Most laundry detergents are phosphate-based, as there are no norms, control or regulation of phosphates use, resulting in deterioration of receiving waters.

The implications of unregulated heavy metal contamination of the waters of Bellandur and Varthur lakes are there for all to see. Vegetables grown around the Varthur lake have been found to be highly contaminated. Regardless of their source, they find their way to big markets in Whitefield, Marathahalli, HAL, Hoodi and other areas.

There is even more danger in the grass grown alongside the water hyacinth nourished by the polluted nutrients. The grass is collected as fodder and sold in truckloads to various cattle sheds. Local people engaged in this task claim they are sold to even dairy farms in Koramangala and Shivajinagar. The city's milk distribution chain could well be compromised.
 
Industrial pollutants have always been the biggest problem for Bellandur & Varthur lakes. But it took a strict ruling by the National Green Tribunal to spur the govt into action. It could not have come without sustained studies by stakeholders 

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(Published 29 April 2017, 19:23 IST)

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