‘Silt in Bellandur and Varthur lakes can be monetised to rejuvenate them’

The silt accumulated over the past four decades in Bellandur and Varthur lakes might help in their rejuvenation.

With nearly 7.3 million cubic metres of silt that can be monetised to earn Rs. 1,800 crore, the rejuvenation of the two lakes can be self-financed, a study by the Indian Institute of Science has revealed.

A team led by T.V. Ramachandra, aided by officials from Madras Engineers Group (MEG), who conducted a Bathymetric survey of the two lakes, has come out with some preliminary observations, according to which there is at least two to three feet of silt sediment, which will amount to 7.3 million cubic metres.

Though the State and Union governments have made all the right noises about rejuvenation, funds are yet to be earmarked.

The Bangalore Water Supply and Sewerage Board has estimated the cost to be around Rs. 900 crore — which is only half the estimated monetary value of the silt in the two lakes.

Mr. Ramachandra said while the depth of Varthur lake was around 10 metres in 1970, the study found that in many points the depth has reduced to even less than one metre, illustrating the extent of silt accumulation.

“The money for the rejuvenation is sitting in the lake itself. The commercial value of the silt which can be used as manure, sand for construction or to make bricks is to the tune of around Rs. 1,800 crore,” said Mr. Ramachandra.

Mr. Ramachandra has also recommended that MEG, whose Eco Battalion has experience with rejuvenating Ulsoor Lake, be tasked with removing silt from Bellandur and Varthur lakes. He said the process can be completed in two years.

The team has also undertaken a toxicology study of the two lakes. Water samples have been collected at every 10 feet along the length and breadth of the lakes, which will be analysed for toxic composition. This will help to pin down the particular chemical leading to frothing. The report will be out by the end of the month, and it will also envisage a roadmap for the rejuvenation of the two lakes.