Arkavathy: A river that is about to disappear

There seems to be little effort on the ground despite warning signs.

Floods in the city prompted civic officials to launch a massive demolition drive. However, there seems to be little effort on the ground to save a river on its death bed.

Once the source of water to the city, the last vestiges of Arkavathy can now only be seen as floodwater. Cauvery Neeravari Nigam Limited (CNNL), which is spearheading ambitious plans for its rejuvenation, said that encroachments had been identified over 70 km of the route taken by the river. However, there is no move to remove them considering that they include residential layouts and industries. “As of now, we are focussing on removal of obstructions to the flow,” said T.N. Chickkarayappa, Managing Director, CNNL.

Officials said the major works involves linking the nearly 67 tanks on the path, which had been blocked either by encroachments or illegal sand-mining. These encroachments will be apart from the 146 unauthorised layouts, 482 non-residential structures and 3,506 residential units identified by Bangalore Development Authority (BDA) in 2013 within one kilometre of the Arkavathy and Kumudvathi.

While the department attempts to grapple with its own ambitious plans to ‘rejuvenate’ the river – previous attempts at attracting global bidders for treatment of effluents and other water recharging solutions had failed – the river continues its slow descent into oblivion.

Where’s the water going?

Experts believe removal of encroachments may not be enough. “The two issues of over-extraction of water through borewells and large-scale planting of Eucalyptus and other water-intensive crops in the catchment area needs to be addressed,” said Sharathchandra Lele of Ashoka Trust for Research in Ecology and the Environment (ATREE), who has been involved in studies of the Arkavathy basin.

For instance, he says, while the area under Eucalyptus plantations was just 11 sq. km. in 1973, by 2013, it had ballooned to over 273 sq. km. “Our study has shown that cultivation of Eucalyptus, vegetables, arecanut and maize has gone up sharply while traditional crops of ragi, pulses, johar and paddy have come down,” he said at a workshop on Arkavathy basin on Wednesday.

Two decades ago, borewells formed just 38 per cent of the water supply to farmers. Now, they are the only source, as open wells and canals have disappeared along with the Arkavathy itself.

“While more borewells are being dug, the failure rate is high. 77 per cent of borewells have failed,” said Mr. Lele.

The unviability of agriculture in the area and the proximity to Bengaluru is resulting in large tracts of land either being left uncultivated or sold for non-agricultural purposes.

Nelamangala, Ramanagaram suffer as Arkavathy disappears

The booming quasi-industrial towns of Nelamangala and Ramanagaram seem to be in the midst of an impending water crisis as Arkavathy river and ground water disappear.

The two towns on the periphery of Bengaluru have seen a marked increase in population between the census of 2001 and 2011. Nelamangala has grown by 48 per cent, while Ramanagaram’s population has increased by 20 per cent. However, availability of drinking water, which is supplied largely through borewells, has plummeted.

ATREE researchers surveyed 900 households cumulatively in these towns.

The study reveals that Nelamangala civic authorities supply just 42 litres per capita per day (LPCD), which is below the 70 LPCD benchmark laid down by the Karnataka Municipal Department for small towns. Ramanagaram receives 72 LPCD while the prescribed quantity is 130 LPCD.

Though both towns cumulatively have 270 public borewells, depleting groundwater is seeing many become defunct, observes Karthik Madhyastha, a researcher at ATREE.

The shortage results in 66 per cent of Nelamangala and 57 per cent of Ramanagaram depend on tankers for water supply during times of shortage – particularly summers.

Moreover, the ‘hard nature’ of the water supplied sees 57 per cent of the surveyed households in Nelamangala rely on purified water from other sources.

Link between water and governance

The intricate link between water and governance was also apparent in the study. The cost of water through borewell was an alarming Rs. 33 per kilo litre in Nelamangala, nearly double that Ramanagaram, which gets a bit of its supply from Shimsha.

“In Nelamangala, barely 10 per cent of the cost of running and maintaining borewells is recovered from consumers,” notes Mr. Madhyastha.

Both towns are barely a few kilometres from Bengaluru where Cauvery water is being supplied through pipes. “Peenya Industrial estate, which is barely a few kilometres away from Nelamangala, gets around 70 MLD water from Cauvery. Nelamangala needs just 1.6 MLD to get out of its over-reliance on groundwater,” he says.