Monsoon here, time for RWH

The long-overdue uptick for RWH is finally here. Around 10,000 buildings in the city may be catching rainwater, by one informal estimate, and the numbers are steadily rising.

Gautam B Pandit and his family were very excited last Wednesday after the heavy downpour in the city. The rain filled up the 5000 litre barrel they have set up in their house for rainwater harvesting (RWH). “We could have filled another two barrels that night. The barrel just overflowed”, Gautam says. The Pandits have just installed RWH at their home on Hayes Road in Richmond Town.

The 40 houses in Sherwood Apartments, located on Kaggadasapura Main Road in CV Raman Nagar, have not faced any water problem for the past four months. All thanks to RWH says the residents. K S Thirumaran, one of the residents of CV Raman Nagar says that he suggested RWH to his neighbours. “They all welcomed the idea and contributed”, he says adding “ The entire apartment depended on one borewell”.

At the Embassy Tranquil Apartments in Koramangala 6th block, Rajiv Kuchchal mooted the idea to his neighbours around two months back. “Everyone was positive”, he says.

Since the groundwater level in their building is high, they adopted the storage method. Now instead of overflowing drains, our sumps get filled, Kuchchal says, adding that they don’t switch on the borewell when there is heavy rain. They collect anywhere between 15,000-20,000 litres of water per day during heavy rains.


Rekha Arun with her RWH system, the blue barrel is the first rain separator(pic: VV)

Pandit, Thirumaran and the residents of the Embassy Tranquil Apartments are among those in the city who have installed RWH recently to combat erratic Cauvery water supply and avoid shelling out money to buy water from tankers.

Bangalore has primarily depended on Cauvery water. Traditional sources of water supply like tanks and lakes are now declining. Groundwater levels have already fallen due to heavy extraction.

In his book, ‘Amruthavarshini’, a guide to RWH, A R Shivakumar, Executive Secretary and Principal Investigator – RWH, Karnataka State Council for Science and Technology (KSCST), states that in the last 30 years, Bangalore has experienced five years of severe drought and three years of moderate drought. The quest for water has resulted in over exploitation of groundwater, he says in the book. “The quantity of run-off water in the storm drains has increased tremendously. RWH is all about conserving this water, thereby, supplementing the present supply”.

In Chennai, during J Jayalalithaa’s tenure as Chief Minister, she made it mandatory to harvest rainwater in both old and new buildings, and also provide a duct for recharging the groundwater. According to the Chennai Metropolitan Water Supply and Sewerage Board, nearly four lakh buildings have RWH.

As the monsoons set in, for many in the city, RWH seems to be the way to address this problem. In 2007, the Bangalore Water Supply and Sewerage Board (BWSSB) made it mandatory to implement RWH for all new applicants of water connections.

T Venkataraju, Chief Engineer, BWSSB, says this is being strictly enforced now. He explains that sanctions for new water connections are approved only after inspections by the Assistant Executive Engineer and Water Inspector of the concerned sub division. “They’ll go to the spot and inspect directly. They’ll see the pipelines and check the filter media. Then they will certify”, he explains. Between April 2008 and May 2009, 3000 new buildings implemented RWH, says Venkataraju.

Implementation of RWH has been made mandatory in Bangalore by two other bodies apart from the BWSSB. The June 2007 Zoning Regulations of the Bangalore Development Authority (BDA) states that the “Provision of RWH is mandatory for all plots which are more than 240 sq metres in extent. A five per cent rebate on the property tax is offered for residential properties and two per cent for non residential buildings within Bangalore Metropolitan Area for the first five years when RWH is made an integral part of the building constructed”.

The Bruhat Bengaluru Mahanagara Palike’s (BBMP) building bye-laws of 2003 also mention RWH. Part IV, bye-law 32 says “Every building with a plinth area of exceeding 100 sq mtrs and built on a site measuring not less than 200 sq mtrs shall have one or more RWH structures having a minimum total capacity as detailed in Schedule XII”. The bye-laws  also mention that a levy of about Rs. 1000 for every 100 sq. mtr will be collected if the owner fails to provide RWH.

B M Tirakanagoudar, Joint Director of Town Planning, BBMP, says that all high rise buildings that have approached the BBMP for plan sanction have RWH. “These owners come to us for Occupancy Certificate (OC). We do not give OC without looking into whether they have installed RWH. But most houses violate this. They do not come to us for OC”, he says, adding that it is not strictly implemented.

Water harvesting boom

Shubha Ramachandran, Water Management Consultant, Biome Environment Solutions Pvt Ltd, says the number of calls they have received for RWH has gone up in the last few months. “People get anxious just before the rains. A lot of people to whom we gave proposals last year, got it done this year ahead of the monsoons”, says Shubha. Since April this year they have received some 150 requests for RWH. They have completed almost 30 RWH implementations since then. *Biome set up RWH in the locations mentioned at the beginning of this report.

The BWSSB in association with the KSCST will set up a rainwater harvesting theme park in Jayanagar, the foundation stone for which was laid last Sunday, 14th June. Spread across 4500 sq ft of land in Jayanagar 5th block, the estimated cost of the project is Rs. 2 crore. The park will house an amphitheatre and exhibition hall. Models of various methods of RWH will also be displayed at the park. Ten-minute films on RWH and water conservation will be screened for the public in both English and Kannada. This project is expected to be completed in six months.

Prashant Hegde who is the Managing Director of Rainwater Concepts India Pvt Ltd says there has been an increase in the recent months. Hegde says owners of new buildings approach them for comprehensive RWH. “This is a positive trend. We get around 3-4 calls everyday. People want to see tangible results. They want direct use”. The company has done 25-30 RWH projects in the last eight months, most of them in buildings without water connections, in areas like Marathahalli and Kaggadasapura, where they depend on borewells or tankers.

Ravikumar S, Chief Consultant, Green Technologies (an environmental engineering company), says they have completed more than 2000 RWH installations (in both residential and commercial buildings) in the last 5 years. But most people are not willing to spend on this, he says.

Though companies see an increase in the trend, there is no record of the number of buildings with RWH installations in the city. Vishwanath S, Founder, Rainwater Club, guesses around 10,000 buildings in the city have RWH.

Shivakumar of KSCST says it is difficult to say how many RWH installations are there in the city. “On a monthly basis, we get about 300-400 enquiries. They ask us to help plan for their house or industry”, he says.

The KSCST offers technical expertise for RWH for residential buildings and small apartments, free of cost. “We tell them what kind of a sump is needed. We take the plan, analyse and prepare a budget”, Shivakumar says. They even offer to train masons and plumbers for this, free of cost. The KSCST has done around 200 large RWH projects in the city including Vidhana Soudha, BBMP head office, BMS Engineering College in Basavanagudi and several hospitals.

Sudheer Prasad's RWH system

Sudheer Prasad’s RWH system: sump at the foreground left side, the recharge well in the far end and the filter hidden behind the bamboo sticks (courtesy Sudheer Prasad)

B G Prasanna Krishna, Director, Welfare Harvesters India Pvt Ltd, who has helped set up more than 75 RWH connections in the past 2-3 months, says the BWSSB is still giving water connections without checking for RWH. He says people pay money and get their connections even without RWH. But Venkataraju of the BWSSB says surprise checks are done to prevent such cases. “If I get to know, I’ll personally take action. The Additional Chief Engineer checks regularly. Give me any detail, I’ll check. I’ll ask the owner”, he says.

Pitching for water harvesting

Irrespective of rules framed by these three bodies, many residents across the city are looking at implementing RWH in their homes.

Sudheer Prasad, who installed RWH at his house in Banaswadi last year, has been proposing the same at his apartment building in Murugeshpalya. “We are trying to do RWH now as there is severe shortage of water there. Although there is Kaveri water connection, the supply is very erratic. Most of the time they buy water from tankers”, he says, adding that the implementation has not begun yet because people have not paid up.

Kishore Kumar, who resides in Manjunatha Arcade in Vignan Nagar, has also proposed RWH details to the apartment association. “People are eager to implement this. The borewell has dried up. We are now buying water from tankers”, he says. At RMV Clusters in Sanjaynagar, Ganapathi Joshy and other committee members of the apartment complex have planned to screen two films on RWH for the residents.

For a city with a population of over 60 lakhs, we receive about 870 million litres of water per day, a quantity that is far from what is required. Now, as monsoons have set in, harvesting water will help both in the short term and in the long run.

* Updated 1 July 2009.


  1. Vishwanath Srikantaiah says:

    People interested in rainwater harvesting videos as applicable to Bangalore can see them here




  2. Srikanth Parthasarathy says:

    ‘Better late than never’ is what i can say!. 2000 RWH connections in the past 5 years is a very less number. It is nothing when compared to the problems that we are facing with water suply and wastage of water!. I am sure there will be more than 2000 apartments being constructed every year in Bengaluru. It should be made compulsory for the builders to install the RWH during the construction itself. Anyway they price the apartments outrageously!

    Not only for those buildings which does not get water supply properly, we need to target at all the residences and commercial buildings to implement RWH as it would help in saving water!

    Also vaish, It would be helpful to quote the price and the technical details in a paragraph somewhere so that readers can get a sense of what it is and how they can plan for the same.

    Videos posted by Vishwanath is very helpful.

    Thanks for the good information.

  3. Vaishnavi Vittal says:

    Dear Srikanth
    You can read the following article by Rainwater Club
    It’s an FAQ on RWH, should answer all your questions.

  4. raghunath says:

    why just rain water harvesting this is seasonal why not the water we use everyday. it is possible to do it with biological vehicle which converts the organic waste into food for itself and eat them which means there will be almost zero sludge settlement this organisum is food for zeolites which inturn is food for fishes. fishes grown in these kind of tanks are more nutreious and well grown they breed faster also since fishes are filter feeds it takes in food and floating particles and leave water out thus making water potable. this can be used for secondry applications like in flush tanks or cleaning vehicles or recharging water bodies.
    the crieteria required is to collect waste water in a place expose it to sun light or tube light and then add fishes after 3 days.

  5. raghunath says:

    why just rain water harvesting this is seasonal why not the water we use everyday. it is possible to do it with biological vehicle which converts the organic waste into food for itself and eat them which means there will be almost zero sludge settlement this organisum is food for zeolites which inturn is food for fishes. fishes grown in these kind of tanks are more nutreious and well grown they breed faster also since fishes are filter feeds it takes in food and floating particles and leave water out thus making water potable. this can be used for secondry applications like in flush tanks or cleaning vehicles or recharging water bodies.
    the crieteria required is to collect waste water in a place expose it to sun light or tube light and then add fishes after 3 days.

  6. Vishwanath Srikantaiah says:

    the first house referred in the article with its rainwater harvesting system Gautam and Gayatri Pandit’s home rainwater harvesting system.

  7. Vaishnavi Vittal says:

    For information on companies that help implement RWH and to join a discussion on water harvesting, please see

  8. SV Nagappa says:

    It is not that hard to do a RWH system. Buy one barrell and harvest rain in it. Connect a water filter to it and then connect it to your other bigger barrel or sump. The filtered water can be used even for drinking as rainwater is pure. However if you collect it from the rooftops etc you may need a strong filter. Simple water harvesting can be done when you use washing machine by collecting rinse water which can be saved and used for watering garden. It has no negative impact on plants. Collect water when it rains and put in a ground recharge well. This is very important as the water will then seep into underground water ( aquafer) and fill the water table. In Blore due to borewells water table has risen up and salt has come up. Added to this is contamination due to old sewar pipes. The more water is added to the aquafer the better the flow of this water and organic processes will decrese contamination of ground water due to organic matter. Everyone can collect rain water in large buckets outside their homes and use it for gardens, planting 2-3 meter trees and for washing clothes. Even if you are in a slum. This will save millions of liters of water and save the ground water environment as well. If you do not look after your ground water environment then your homes will develop cracks and the salt will erode the bricks. It is high time Bangalore citizens started to look after themselves and participated in governance rather than wait for passive government handouts. Take a hand up not a hand out.

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