Water supply from the bottom up

By Revathi Siva Kumar on July 7, 2015 in Environment and Ecology
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Water supply from the bottom up

Rainbow Drive, an apartment complex of 200 houses seems to be all that the name suggests -- tree-lined pathways, moist breezes, and verdant gardens. But no one would believe that this is situated on Sarjapur Road, the ‘waterless colony' as this region of south-eastern Bangalore is being called in private circles.

Rainbow Drive was beginning to go the way of all ‘dry' colonies just four months ago. It does not have a water supply connection from the Bangalore Water Supply and Sewerage Board (BWSSB), and has been dependent on its rapidly depleting borewells.

According to a resident, Jayawanth Bhardwaj, formerly software engineer with Microsoft, but now involved mostly in community projects, the colony had used up five of its seven original borewells, and was living on its last two, which were decreasing in yield rapidly.


A rain barrel in one of the homes at Rainbow Drive, Sarjapur Road. Pic: Rainwater Club (RWC).

Four months ago, there were just two borewells in use for 200 houses, he explains. Half the colony used one well, while the other half used the second one. The spectre of water scarcity and reliance on tankers was beginning to loom large for a few residents, while others were not even aware of the situation.

Today, though, things are different. In just three months, the apartment complex has turned around. Seven public (open) wells have been dug for ground water recharge, 20 homes in the layout have implemented rain water harvesting solutions (of various forms) and this includes around 10 private wells in these homes.

Read this quick primer by for Bangaloreans on borewells, open wells, recharging, and undergound acquifers as you proceed to read about how Rainbow Drive did it. It is authored by Avinash Krishnamurthy of Rainwater Club.

Rainbow catching rain

The transformation began with the Rainwater Club (RWC) meeting people at the Rainbow Drive in March 2008. RWC is a group of dedicated individuals catalysing the rainwater harvesting movement in Bangalore. They work as solution providers for rainwater storage and supply in homes and layouts.

According to Avinash Krishnamurthy, for RWC who worked on the project with Bhardwaj, layouts in Bangalore typically have 55 to 60 per cent of their land as residential sites. 60 per cent of of rain falls on rooftops of the homes. RWH can be done at the household level, since rain falling on rooftops is the cleanest.

For each of the 20 houses at Rainbow Drive, custom rainwater harvesting solutions - involving rooftop harvesting, private recharge wells, collection into sumps, and rain barrels for utility water storage - have been implemented, depending on the preferences of owners. Some residents prefer to use collected rainwater only for utility purposes such as washing, others decided to store the collected and filtered water in their sumps, says Krishnamurthy.

Rainbow Drive represents perhaps the fastest implementation of RWH projects on such a scale, says Krishnamurthy. It is also probably the largest ‘welled-in' layout in Bangalore today, he adds.

Of course, in just three months, the effects of recharge cannot be felt immediately, especially as it has not been raining too much. "Either recharge of the acquifers supplying borewells will happen or the open wells themselves will yield," says Krishamurthy.

Rainbow Drive's plan is to distribute a whole set of recharge wells across the layout to replenish ground water, says Krishnamurthy. Whether the existing borewells' yield improves or whether the recharge wells themselves will start yielding water (open wells) is not clear, he acknowledges. However, the danger of tankers supplying water for daily use has receded.

How it happened

The turnaround was not immediate, mostly due to the initial reluctance of the people. "Residents believe water is naturally ‘generated' underground," explains Bhardwaj. "So they just want to get water for free, without putting in any effort to regenerate it. If we say let's dig a well, people immediately withdraw. They respond only if there is a crisis."


A recharge well in common storm water drains with filter. Pic: RWC.

Bhardwaj's experience has been that builders are a reluctant lot too. The usual question is posed by them is: "Does RWH really work?" But in a collective sense, even if builders find it imperative to implement these solutions, it is crucial that people should drive the builders. Otherwise, on their own, they refuse to take action, feels Bhardwaj.

Seven years ago, there were 70 residences in Rainbow Drive and seven borewells, and a general feeling of luxurious living. With increasing usage and decreasing investments, however, the borewells began to dry up and the water quality began worsening, creeping towards a crisis stage, even though the residents were not completely aware of it.

Recalling the creeping realization that something was wrong, Sushil Kumar Nahar, another software engineer and resident here recalls: "The water from borewells did not get processed, it only went into a common tank. Earlier, we never got stones in water. But for the last 2-3 years, we got some slate and sand in the water, which proved that the water level was hitting deeper and deeper levels. That is when we became active and started promoting RWH."

Adds K P Singh, another resident and committee member: "We became sure that if have one dry season, then we will have acute scarcity.

A recharge well has been dug, and after the ring is placed properly, a worker is untying the ropes tied to the ring. Pic: Jayawanth Bhardwaj.

Krishnamurthy says that the first meeting with Jayawanth took place in February 2008 to explore the possibilities. They discussed critical questions and decided to implement 40 wells within the 32 acres, starting March 2008.

The first meeting was held with 32 residents, explaining in simple, non-jargonised terms about the process and price of harvesting water, both at homes and at common (public) areas in the layout. The meeting was critical, because it talked about the project and what was most appropriate.

At the end of the meeting, about 20 were convinced. And once the wheels began to turn, there was no stopping it.

Next, the residents needed convincing that their harvesting techniques were practical, simple and effective. The Residents' Welfare Association had one member, who suggested that all the rooftops would divert the rainwater to a single recharge well! That was because some have read and heard about rainwater harvesting, Bhardwaj recalls. But usually their perception is that implementing it is tough, as it is inaccessible and requires ‘other' people to put the processes into motion.

Once Rainbow Drive began the process, the implementation, with the help of the Rainwater Club, took place at two levels. One was to tap storm water and run-off from parks, drains and other open spaces and direct the water into open wells to recharge groundwater. Secondly, was trying to get individual houses to implement these projects. They motivated 20 to 25 houses to execute such projects.

The team surveyed and installed recharge wells at critical points in the locality. There are three kinds of recharge wells at Rainbow Drive currently, with capacities of 16 kilolitres (KL), 8 KL and 4 KL. Their plan is to invest Rs.2.5 lakhs this year and increase the number of recharging wells further.


A 5ft 30ft recharge well in the common area. Pic: RWC.

One can detect the interesting crisscrossing of recharging wells and pipelines throughout the colony, which is open to public inspection. The stormwater drains from the streets carry run off water to a bed of stones that filters out the wastes. The water is then passed through a desilting chamber, from where it runs through a couple of laughably simple netlon sheets. The water then flows into check dams through pipes. This water is then run into the public recharge wells and from there it recharges ground water, by percolating through the top soil.

Water pricing

After implementing phase I of the water harvesting in their layout, Rainbow Drive's next step was to work out pricing.

Rainbow Drive water tariff slabs (Per month)
First 10,000 litres, Rs.10 per KL (Rs.100)
Next 10,000 Rs.15 per KL (Rs.150)
Next 10,000, Rs.25 per KL (Rs.250)
Next 10,000, Rs.40 per KL (Rs.400)
Above this, Rs.60 per KL

The Rainbow Drive residents' welfare association (RWA) runs the water supply system for the layout. The borewells (these are independent structures from the recharge wells) are connected to overhead tanks and piped water from the tanks reaches every household. Each home as a meter, from which a bill is generated each month.

Earlier, while the pricing policy put the rates of water at the colony below BWSSB's reference consumer rates, the RWA realised that the expenses simply required them to raise the water rates anyway. A lot of maintenance work and costs were linked to water. For instance, the costs of sewage treatment plants per month added up, with their maintenance running into several thousands. To this the costs of maintaining the public recharge wells was going to get added.

Moreover, while an average person requires about 135 litres per day, there was higher level of wastage in the homes. "We needed to have sewage connection and electricity bills and ground water recharging too," explained Manoj Dighe, another resident.

The residents realised that their pricing policy needed to include an understanding of water as precious resource. They worked out a rate where upto 30 KL of water per month per household (which is 250 litres per person per day in a household of four) is charged at Rs.500.00, which is a around Rs.17 per KL. Beyond that, the rates go up even higher in slabs, in part to provide disincentives for over consumption and wastage. Households that have implemented RWH projects are given discounts.

"A fair and balanced pricing policy is crucial, as it is the greatest leveler and control agent," says Bhardwaj. "The RWA is now playing the role of BBMP/BWSSB within the layout for land use and water supply," says Krishnmurthy.

Rainbow Drive, Sarjapur Road
Jayawanth Bhardwaj
jayawanth_b AT hotmail DOT com

Rainwater Club
1022, 6th Block, 1st Floor, HMT Layout,
Vidyaranyapura Main Road,
Vidyaranyapura, Bangalore - 560 097
rainwaterclub AT gmail DOT com.

Today, as they look back, they find that their attempts at facing challenges and convincing skeptics have been vindicated, when they see the opponents of RWH projects turning round to defend the very same policy they originally opposed. Perhaps the water supply board can even take a leaf out of their pricing policy, suggests Krishamurthy.

There are other benefits too. Manoj explains: "Initially houses near the gates would get clogged. Now it doesn't happen. So we have a dual advantage----wells get recharged and secondly the houses near the gates don't get flooded due to the overflow of rainwater."

Meanwhile, the steps that Rainbow Drive has taken have come to symbolise the power of collective action and simple technology. It may soon become a model not only for other layouts on Sarjapur Road, but even for the increasingly water-starved colonies of the city.

First published on Citizen Matters



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