Can Roman ingenuity solve Bengaluru’s water crisis?
In the middle of the first century AD, the Roman inhabitants of Nimes in Provence decided they wanted more water for their city than nature had seen fit to grant them. So, they spent a hundred million sesterces on a solution. Near Uzes, Roman engineers found an abundant source of water and they drew up plans to divert the water 75km through mountains and valleys using an ingenious system of aqueducts and underground pipes. When they encountered the enormous gorge of the River Gard, they did not despair but calmly went back to the drawing board and erected a massive three-tiered aqueduct, 360 metres long and 48 metres high, with a carrying capacity of 40,000 cubic metres a day. This ensured that the inhabitants of Nimes would never again suffer the torment of a shallow bath, according to the author/philosopher, Alain de Botton.
Cut to 2024 in namma Bengaluru, where, despite having in our midst 50,000 world class engineers tasked with providing medical, engineering and technology solutions to Los Angeles and San Francisco, we are at the mercy of the tanker mafia for one of the most basic human essentials: water.
In 1950, Bengaluru’s population was about 746,000; today it is 14.4 million, not counting the April and May 2024 influx. From Kempegowda to the Wodeyars, the founding fathers of our city were visionaries who may well have had access to the Roman playbook, given their creation of a network of lakes, interconnected raja kaluves, drainage systems and an abiding respect for the laws of gravity, using the undulating terrain of Bengaluru which varies from 750 to 962 MSL. There’s a good reason why High Grounds is so named; it stands 70 m higher than Varthur and no Holmesian powers of inference are necessary to do the math on this one. The Palace will remain regal, Epsilon will become Nautilus.
Our water supply from the Cauvery, which is 100 km away and 300 metres below the city, is 1,450 million litres a day, which sounds enormous until one realises that our unique micro-climate has blessed us with the equivalent of 3,000 million litres a day, which we fritter away in the sea thanks to poor planning, rampant urbanisation, callousness, and apathy. And let’s not forget our visionary leaders: what we gained on the roundabouts in terms of magical weather we lost on the swings of political fortune. So is it all gloom and doom or do we have any silver-bullet solutions at hand?
Architect and visionary Tony Kunnel recently had a Eureka moment in which he envisioned an RBI of water. Our problem has always been pockets of surplus and shortage, with hailstones in Madiwala contrasting with parched conditions in Hebbal. What if we had two massive 20 km tunnels on a Jobo grid, running 20 m below the surface from North to South and East to West, sunk using DitchWitches and tunnel-boring machines, concreted and fitted with submersible pumps which collected the surplus floodwater from say, Varthur, and pumped it to the empty Yediyur Lake in Basavangudi? The underwater tunnels could double up as transport waterways, the lakes would never run dry and who knows, within a decade Bengaluru could recover its fabled micro-climate and be rechristened air-conditioned city? A project of this magnitude could cost as much as Rs 7000 crore: a drop in the ocean when one considers the target. If Bengaluru’s real estate turnover was $130 billion in 2023, a billion spent on good water and good weather is chump change.
Meet Vishwanath Srikantaiah, aka Rainman, who raises a few practical questions. “By and large, it’s a good, if somewhat radical, idea that will involve a huge capital outlay. We have 60 rainy days in a year, of which 40 days see less than 1 cm and only 10 days have significant rainfall of over 5 cm. So my concern is that the tunnels will be under-utilised. We also have 1,440 million litres of treated waste water from 50 STPs which we can use to fill the lakes.”
So is this tunnel idea a moon-shot?
“I am not here to shoot down ideas that benefit the city. However I think there are far more practical problems we need to prioritise. My vision is for the city’s civic authorities to work in tandem, rather than at cross-purposes. Take Ulsoor Lake, for example. The land is owned by BBMP and the Army, no one knows who owns the sewage discharged into the lake, and the BWSSB is responsible for the sewage treatment plant: the outcomes are bound to be chaotic. If, on the other hand, we had one nodal agency with overall responsibility, we could deal with the problem far more effectively. We need qualified hydro-geologists on BWSSB rolls, they would be able to tackle the problems unique to urban lakes, as opposed to the existing engineers who are competent at agricultural lakes but lack the domain knowledge to deal with urban issues.”
So what would you spend the money on? Viswanath responded, “I would create a dedicated groundwater cell within the BWSSB tasked with vertical electrical sensing, and a core team of crack hydrogeologists who would map the contours of Bangalore’s aquifers and then come up with a data-driven masterplan to handle rainwater, water-table management, wastewater treatment, usage and discharge into select waterbodies.” A sort of Covenant of Water?
He chuckles wryly before responding, “In the short term, we can look at efficient methods of using treated water that is not potable, for example in agriculture, where the sewage water is actually good for plants. Create a groundwater cell who will focus on replenishing the water table.”
Let’s get the basics right, fellow Bangloreans. Otherwise, to paraphrase a French queen, there might come a day when the thirsty are dismissed with, “Let them drink beer.”
(The writer is a Bengaluru-based author and promoter of comedy and musical shows with an abiding passion for civic issues)