Dry run in Bengaluru

By Umesh Anand

RIGHT in the middle of February, when Bengaluru should have been celebrating salubrious weather and enjoying the warm glow of its technological and financial successes, the taps of a third of its population ran dry.

How is it that an emblem of modern India, a city advanced and sophisticated in multiple ways and burgeoning with activity, suddenly finds itself waterless?

Incredibly, that is exactly what has happened in Bengaluru. The city was fine one day and the next day it wasn’t. Just like that and without warning, an estimated 4.5 million residents in the north and east of the city found they didn’t have water to cook, wash their dishes or take a bath. They account for a third of Bengaluru’s population of about 15 million.

These were people who were being supplied groundwater from aquifers under the Bellandur and Varthur lakes. But aquifers need to be recharged and both lakes have been kept dry for the past two years to be desilted. Diversionary channels have kept all flows including sewage and recycled water from getting to the lakes.

Water was supposed to arrive from the Cauvery river, but the project is  delayed by two years. So, while parts of Bengaluru do get Cauvery water, these 4.5 million residents as yet do not.

In the meantime, the aquifers continued to be drawn on without replenishing them till the groundwater finally ran out and with it the supply to homes.

Shouldn’t the city have been forewarned? Bengaluru doesn’t monitor its use of groundwater. There has been no groundwater cell in the Bengaluru Water Supply and Sewerage Board and it doesn’t have a single hydrogeologist, says S. Vishwanath, civil engineer and urban planner by profession and insightful water expert.

This is stunning considering that Bengaluru relies extensively on groundwater across the city. It is included in the municipal supply. Tankers commonly meet the needs of bulk users such as high-rise buildings and hotels.

Screeching headlines followed the recent crisis in Bengaluru. It is not the first time. For long, Bengaluru has been ranked among cities that will run out of water even as it flourishes.

Does it really need to be so? Bengaluru receives plenty of rain in a year, but doesn’t do enough to catch it and put it to use. It has lakes in hundreds which should be an insurance against shortage. However, the authorities and the citizenry have allowed them to be encroached on and sullied by the dumping of sewage in them.

For a modern city with a high-tech tag, Bengaluru also seems blissfully oblivious to the metrics of its own growth and prosperity. It has expanded in any which way and supply hasn’t matched increases in population. There is no serious effort to rationalize the use of water. It doesn’t get priced properly nor is recycling adequate.

There are efforts to do things better. For example, Vishwanath’s Million Wells Programme seeks to make the city more sustainable through a proliferation of open wells. It remains a work in progress. Some bulk users have been harvesting rain, but it is not enough.

Bengaluru’s story is really the story of every Indian city. Water tables are falling, usage is wasteful, pricing is out of whack and recycling is virtually non-existent. As urban populations boom, the future of Indian cities in resource terms is full of foreboding. Terrible things are either happening or on their way and, caught up in the exuberance of an emerging economy, nobody seems to want to be bothered.

To find out more about the current Bengaluru crisis, we spoke to Vishwanath at some length. We covered the Million Wells Programme in our  November 2019 issue. But here is an edited version of our interview with him after the recent crisis broke.

 

Q: From time to time, a headline pops up that Bengaluru is going to run out of water. It is a headline again. What’s happening?

It is a perfect storm. What has happened is that there was planned addition of 775 million litres per day to the city’s water supply from the Cauvery river last year. The project, called the Cauvery Phase-5 project, was delayed due to Covid. In the meantime, the city administration started to desilt a lot of the lakes we have to make sure that rainwater comes in and that the lakes are improved. Diversion channels were created to prevent any flow into the lakes. The two largest lakes, Bellandur and Varthur, which are 364 hectares and 200 hectares in size, respectively, are as a result bone-dry. What this means is that there has been no recharge of the aquifers for the past two years at least. The aquifers have been constantly used without recharging and have emptied themselves out. That is why there’s a crisis. It’s not a crisis for those who are connected to the Cauvery water line. So, 1,470 million litres per day is reaching 1.1 million connections in Bengaluru. Roughly about 11 million people are getting Cauvery water. There’s a bit of scarcity for them too, but it’s not a crisis. But for those who are completely dependent on groundwater, through bore wells and tankers, it’s a crisis. 

Bringing lakes back to life is important

 

Q: Aren’t 1.1 million connections a relatively small number in a city as large as Bengaluru?

The calculation is 10 users per connection so that makes 11 million users.

 

Q: How many people would be left out right now?

That could be anybody’s guess because we haven’t had a census since 2011. The population of Bengaluru could be 14.5 million to 16 million, based on an extrapolation from 2011. A reasonable figure would be 14.5 million.

 

Q: There would be four million to five million people left out…

Yes, yes.

 

Q: Which parts of the city right now are actually in this bad zone? 

The north and the east. The Cauvery line comes in from the southwest, so the areas in the southwest and the west are reasonably covered. The city centre is covered. The south is covered, the north is partially covered all the way to Yelahanka but that’s where it’s going towards the airport.

In the east, the Madhepura and the Whitefield IT sector area have been most impacted. That’s the pocket where Bellandur and Varthur lakes have been desilted and have had no recharge potential. 

 

Q: Couldn’t this have been foreseen? 

If we had kept tabs on the groundwater table very accurately with an adequate number of measuring stations, then we would have been able to predict it. The big challenge for our city is we don’t have a groundwater plan. This despite the fact that there are four to five million people completely dependent on groundwater and another five million who are partially dependent on groundwater.

The Bengaluru Water Supply and Sewerage Board (BWSSB) does not have a groundwater cell. It does not have a single hydrogeologist. It draws on groundwater authority folks only to identify points for drilling. But there is no groundwater management plan for recharging aquifers, finding out how much is being pumped out and what is the demand, determining water quality.

Prediction of this crisis would have only been possible if we had the groundwater cell or a groundwater department keeping a close tab.

 

Q: You mean about one-third of the city depends on groundwater, but you actually don’t have any way of understanding how you’re consuming that groundwater. 

Absolutely. Even the number of bore wells is a guesstimate. One guesstimate says that it must be about 500,000 bore wells and we may be pumping out 600 million litres per day. 

Guesstimates vary from 400 million litres to 600 million litres a day. That’s a substantial amount of groundwater that’s being pumped out. 

 

Q: When aquifers run dry, they are not easy to revive.

Luckily for us, we are a hard rock terrain. Unlike the Indo-Gangetic plains where if you drive out water from the aquifer it, sort of, collapses on itself and loses its ability to be recharged. In hard rock terrain, the storage capacity is small, but the aquifer is capable of being recharged.

One of the quick things that I believe we should do is to make sure that tertiary treated wastewater is directed into the lakes during summer to fill them. Even now, if we feed the lakes with tertiary treated wastewater, the groundwater table will quickly revive within a matter of 20 days to 25 days. 

 

Q: Is that going to be done? 

One is pushing for that with the BWSSB. Luckily, the authorities are all listening and are in sync. But the Bellandur lake is being desilted under the orders of the National Green Tribunal. It is a legal hurdle that will have to be overcome because the lake hasn’t been fully desilted. So are we allowed to fill tertiary treated wastewater now as an emergency measure or do we have to wait for another two to three years for the full desilting thing to happen is a question which is being discussed. 

 

Q: Going forward, would Bengaluru continue to be dependent on groundwater for at least a third of the city? This scenario does not change. 

Right, it doesn’t. It doesn’t because the city is fast expanding and the projects which bring the Cauvery water are lumpy. They’ll bring water, 775,000,000 litres per day for a projected population, but that projected population is growing quickly. The next infrastructure project takes another 10 years to come. In that 10 years, the people added to the population will be dependent completely on groundwater. 

 

Q: What was the population figure they were planning for? 

They anticipated 14.5 million people by 2030. But that is the number of people we already have. When the Cauvery Phase-5 project is completed, hopefully in May or June, the water will be consumed immediately. The incremental growth in the population of the city will be demanding groundwater.

 

Q: Bengaluru gets a lot of rain. You have a ‘million wells programme’.  How many open wells have been dug?

So far, 250,000 recharge wells.

Water harvesting and open wells are the solution

 

Q: Has there been any attempt by the government or residents’ groups or, say, other well-meaning citizen groups to speed up this process? Water harvesting is obviously a solution. 

There is. But here’s the thing. What happens is if you’re connected to the Cauvery water, you actually don’t feel the problem of water shortage. While there’s been a reluctance here to do it in the city centre,  on the periphery there’s been an interest. But on the periphery, the fact is that recharge wells have to be supplemented with lake water. On their own, recharge wells will not be able to do a sufficient job. There is definitely much more of an interest. The Bruhat Bengaluru Mahanagara Palike (BBMP), for example, is now taking up a 1,000 wells project in parts of Bengaluru. They want to make sure that every park has a recharge well. They’re also putting in place a plan by which stormwater drains will have recharge wells. The Metro is now interested in putting recharge wells all across its lines. There is interest, but the speed of execution and implementation needs to be much higher than it is now. 

 

Q: How soon would you like to see a million wells come about? 

Yesterday. But if we set ourselves a target, and if you make it mandatory for every citizen to do water harvesting, it should get done in a matter of three to four years. 

 

A recharge well at IIM Bengaluru

Q: But individual harvesting doesn’t solve the problem of recharging aquifers.

When there are large institutions like, for example, IIM in Bengaluru or the railway factory or campuses like the Indian Institute of Science, they benefit themselves because the groundwater mound that is created helps them. IIM itself reports that because they’ve done a lot of recharge wells their groundwater is stable.

Obviously, it can’t happen at an individual level. It has to happen at a ward level or at a watershed level. But large institutions have a significantly higher role to play in making sure groundwater becomes stable for them.

 

Q: In effect, they are saving their water, raising their groundwater table level, using more of their water and less of the centralized supply?

Yes. The Rail Wheel factory, for example, draws about 300,000 litres from open wells, not deep bore wells. The difference is this, that a deep bore well would typically need a 10 hp pump. With an open well a 1 hp pump is enough so the energy consumption is much less and the carbon emissions as well are less.

 

Q: Has there been any change in the rainfall patterns in Bengaluru? 

This has been the longest dry period we’ve ever had. It’s been about 84 days since we have seen rain.  Never in Bengaluru has there been this kind of a dry period. Not only a dry period, but with the temperature reaching 36°C. For Bengaluru, 36°C in February is something unheard of. And it is completely drying up the soil. Even when the next rain does come, the soil will be so thirsty that there will be nothing for the aquifers. The soil itself will drink up all the water. 

A small filter plant for treating water

Q: There is a change then in rainfall pattern and….

And the intensity of rainfall has increased whenever the rainfall occurs. Previously, we used to design all our rainwater systems for 60 mm per hour intensity. Now at points of time for about five minutes to 10 minutes, the rainfall is 240 mm per hour.

 

Q: Do your water harvesting systems then need to change? 

Luckily for us, what we have mandated for Bengaluru is a 60 litres per square metre roof area, right? It is future-proofed to a large extent. But we’ll have to redesign our stormwater drains or rainwater gutters. Everything will have to be redesigned. 

 

Q: How much effort is made in Bengaluru for controlling consumption?

Every connection is metered. Bengaluru is the only metropolis with 1.1 million connections where there’s a bill sent every month based on volumetric consumption, and there’s an increasing block tariff. There are three systems of tariffs: domestic, non-domestic and industrial. The industrial tariff is really high. It’s Rs 90 a kilolitre. The non-domestic is also very high. But the domestic sector is hugely subsidized. Therefore, there’s no incentive to consume less for the domestic sector. There is no willingness to charge. No government wants to raise the tariff. The last tariff revision plea by the BWSSB has been pending for the past five years.

 

Q: As the population increases, what is the consumption pattern?

Because there’s such scarcity in the system, we get water twice in a week or at best three times in a week. Typical consumption is 100 litres per capita per day. But in flats, typical consumption is 160 litres. 

 

Q: Why does it go up in flats?

It’s not clear why. I think apartments rely on a combination of Cauvery, bore wells and tankers. And they don’t really pay attention to how much they’re consuming. In a residential building you usually get only one source of water. 

 

Q: And how often is the supply?

It’s only in the morning hours for about four hours, twice in a week. I get water in my house on Tuesdays and Fridays. That’s it. 

 

People scramble to get a share of water in a Bengaluru neighbourhood

 

Q: Bengaluru is supposed to be one of India’s most advanced cities. How do you explain this failure to bring about change with regard to water?

Well, there is change and there’s no change, but the thing with us in civil society and other places is we don’t work a lot on institution building. The biggest institution, the BWSSB, needs to be capable in terms of human resources in all departments and financially be able to handle the problems of the city. Like I pointed out to you, it doesn’t have a hydrogeologist, so groundwater doesn’t exist for them. They need a specific cell for wastewater reuse. Right now they have a wastewater cell which is only looking at treatment to meet legal standards and then they don’t know what to do with it, so they’re releasing it, right? We need a well-rounded institution, which has the expertise and access to capital to invest in expansion and maintenance. The problems they face are very difficult and I am more and more sympathetic to them.

Locating sewage treatment plants is an example. There’s nobody who wants sewage treatment plants within their area. Nobody wants it. So you run it in a stormwater drain and then the environmentalists jump on you. And then some powerful minister wants a separate water line to his constituency. So, it’s the institutional governance which is the key challenge. And then the second challenge is one of imagination. 

 

Q: Some of the wealthiest people live in Bengaluru and they intervene in institutions all the time. Why not water?

I think that the richest people not intervening is a blessing in disguise because they’re generally anti-democratic in their interventions.

As Bengaluru grows, demand outstrips supply

Q: What about reuse?

We have a rule which says that if you have a set of 20 and above flats you have to have your own wastewater treatment plant and you have to recycle every drop of wastewater. We have something like 3,600 decentralized wastewater treatment plants, the single largest for any city that I know of. But these wastewater treatment plants have the difficulty of the apartment owners’ association having to run them. The technology choice made by the builder is usually the cheapest technology choice. Then he hands it over to the apartment owners’ association and runs away. These guys are then left with this baby to take care of, which is very, very difficult to take care of.

The city itself has started to decentralize its wastewater treatment plants. We have currently 34 wastewater treatment plants of the BWSSB  and more are being built now. The plant size is 10 million to 20 million litres per day.

 

Q: What would you do with the water that comes out of a decentralized plant? 

We link the plant to the local lake. Wastewater goes in through a constructed wetland and there’s polishing of the water.

 

Q: And how difficult is it to make people use this water? Not necessarily drink it but use it.

Indirectly, you can. What you need to do is to just let it into the lake. It recharges, there’s no problem at all. We have to use the psychology of people. This way we keep the ecology of the lake alive. We retain the livelihood of those who fish. And then we also use the water functionally. That’s what we have done in Devanagari. 

 

Q: Bengaluru is a city of lakes and so on and so forth. Where do you stand in terms of the lakes?

It’s a sad story. We have 210 lakes left, of which only 186 have water. But at least if we protect these 186 lakes, it would benefit us, especially the larger ones like Bellandur, Varthur, and Jakkur and Yelahanka here. But more important are the lakes on the periphery outside the city boundary, which are all getting encroached upon and construction debris is being dumped in them. They will be the future problem spots for groundwater depletion, and we’re doing absolutely nothing about it.