Precariously perched on the edge of an unprecedented drinking water crisis, Bengaluru and its urban sisters across the State are in deep despair. Delayed, inconsistent and inadequate, the Southwest monsoon has offered little comfort thus far, as urban Karnataka’s near-total reliance on rains lies thoroughly exposed.
Hitting global headlines, the prospect of Bengaluru running out of water in the near future had triggered a frantic search for alternatives. But did that urgency dawn too late? It appears so, as the dangerously low levels of reservoirs feeding the city threaten to cut-off supplies by September.
This grim picture of over-dependence on surface water repeats disturbingly in Tier-2 cities and small towns of Karnataka. Dried up, silt-filled lakes; discarded borewells that could not find water even at depths of 1,000ft; tanker supplies once unheard of... in town after town, these scenes are now the norm.
In Hosapete, a town of over 2 lakh people in Ballari district, the close proximity of the Tungabhadra dam always gave comfort.
But in the height of this summer, water got so scarce that piped supply was limited to once in four days, only marginally better than the weekly distribution to Ballari town.
Swathes of silt
Descending into the dam’s backwaters, vast swathes of silt greet you to tell a story of poor management and foresight. “This dam was designed to hold 130 thousand million cubic feet (TMCft) of water. But today, 30 TMCft is filled with silt, effectively reducing the reservoir’s capacity to 100 TMCft,” notes Janardhan Huligi, chief coordinator of a Koppal-based farmers collective.
In 2017, determined to upgrade the reservoir capacity, the collective took the lead to raise funds locally and launched a massive desilting exercise. “Deploying earth movers, 1.5 lakh cubic metres of silt was removed. The water that you see there today is due to that effort,” Huligi says pointing at a big pool on the otherwise dry bed.
This year, the election code of conduct had delayed the process. “But we restarted it on June 4, and have removed 40,000 cubic metres of silt so far. The funds were raised locally without any support from the government. The removed silt, rich in manure, is taken away for free by local farmers,” Huligi told DH.
Collective and individual efforts offer a ray of hope in an otherwise dismal landscape. Not far away from the dam, a Karnataka State Reserve Police (KSRP) battalion with over 600 personnel and their families has to rely on borewells fast running out of water.
Thanks to a KSRP inspector’s untiring efforts, a 210x80x10 metre tank is now being built inside the battalion’s campus by Karnataka Neeravari Nigam Limited.
Fed by rainwater and inflow from the Tungabhadra dam, the tank could soon hold 9-crore litres of drinking water.
Can this be a model for the water-starved towns of Koppal, Ballari and Raichur?
No such tanks are anywhere in sight, as one enters Basapur, on the outskirts of Koppal town. Awaiting intermittent water supply from a panchayat tap, Gudadappa laments: “Although we sink a lot of borewells, there is absolutely no water. In the last four months alone, we have drilled seven wells in vain.”
Piped water supply is painfully slow. “It takes over half an hour to fill just one pot. Even the panchayat water tankers come only once in five days,” he says.
This can get much worse in the rural hinterland. In water-starved Nibbagur, a small hamlet in Davanagere district, villagers leave at 3 am with pushcarts to seven borewells inside a dried up lake two kilometres away. “Over 20 such pushcarts wait in queue as water drops in spurts from the borewell. After filling 4-5 pots, we have to wait 30 minutes for the next spurt,” says Parvathamma, a resident.
To quench the thirst of two lakh Koppal residents, water from the Tungabhadra reservoir is lifted to tanks and piped to the households. “But industrial pollutants from sugar factories have severely contaminated the groundwater. There is high arsenic and fluoride content,” M S Patil from the local Agricultural Extension Education Office told DH.
But as groundwater levels have dipped below 500ft in Koppal, equitable surface water distribution has not extended beyond the town’s core. In Bahaddurbandi on the periphery, supply from public taps lasts just an hour daily. “For many years, this has been the scene. But this year, it’s been extreme,” says Irfan Malipatel, a resident.
The pathetic state of this suburban pocket hundreds of kilometres away from the State capital finds an arresting echo in Bengaluru’s periphery. If normal rainfall bypasses the city even in July, big trouble looms. But for years, this acute shortage has been the norm in the 110 villages added to the city in 2007.
The Bangalore Water Supply and Sewerage Board (BWSSB) supplies 1,450 million litres per day (MLD) every day in 575 sq km where its network exists. An estimated 400-500 MLD is sourced through thousands of borewells dug on the outskirts. But with fast-depleting groundwater, this is unsustainable.
Dependent on private tankers for years, residents on the periphery have an assurance from BWSSB Chairman Tushar Girinath: “Over the next five years, an additional supply of 775 MLD under the fifth stage of the Cauvery water supply scheme will reduce groundwater usage.” But can the city afford to wait? “Nobody knows the quantum of groundwater, and hence nobody can predict how long it will last. Yes, the rate of extraction is faster than the rate of recharge. Nobody can tell when it will get to zero,” says Girinath.
This uncertainty should have spurred BWSSB to arrest the huge quantum of Unaccounted For Water (UFW) that once stood at an astounding 50% of the supply. “Today, we have reduced this to 36%. Distribution losses account for 22% and 12-14% is due to unauthorised connections, classified as pilferage,” informs the Board’s Engineer-in-Chief Kemparamaiah.
Despite these small gains, the city’s fall into a waterless abyss appears disturbingly certain. But a rescue attempt can still be made with a robust lake rejuvenation effort. Articulating this is Dr T V Ramachandra from the Indian Institute of Science himself, the man who predicted the city will run out of water by 2020. His contention is this: Bengaluru city’s annual requirement is 18 TMCft. By desilting and rejuvenating the existing lakes, raising the groundwater table and ensuring a robust rainwater harvesting system, the city can potentially generate 15 TMCft.
If unregulated development has played havoc with the city’s lakes, the failure to desilt lakes at regular intervals has punctured the ability of small towns to sustain themselves.
If lakes are not desilted, the exposed clay solidifies due to heat, preventing infiltration of rainwater. “Around Nagashetty Lake, people used to get water at depths of 100-150ft. But once the land was allotted to Antariksh Bhavan, the groundwater table dipped to 700ft in five years. Today, there is no water even at 1,600 ft,” he said.
But could a one-size-fits-all approach work across the State? Not at all, as illustrated best by the peculiar soil profile of Chitradurga town and its rural hinterland with poor water-holding capacity. “Wind is the enemy here,” notes Dr N J Devaraja Reddy, hydrologist and rainwater harvesting specialist.
The soil is barely a few feet deep. “Chitradurga holds the second highest wind record in the entire country after Kanyakumari. The soil gets blown away fast, and this erosion is historical. Through June, July and August, the wind sweeps the area at speeds of 5 metres/second,” he told DH.
At such high speeds, the wind blows away moisture-holding soil at an alarming rate. “An estimated 600 mm of moisture is lost every year this way. If you analyse 100-year rainfall data, Chitradurga has recorded drought for 60 years.”