AR Shivakumar is one of the pioneers of rainwater harvesting in India who foresaw the water problems that the country would face.

Hailing from Bengaluru, the 65-year-old built a rainwater harvesting system in his house in 1995.

The retired senior scientist of the Indian Institute of Science (IISc) has trained thousands of people, including different governments, on how to create rainwater harvesting systems (RWH) in cities and towns.

Shivakumar believes that a lot of water being wasted due to mismanagement can be prevented through RWH. He says that it can effectively sustain the city’s water supply.

While building his house, he analysed water bills and water consumption patterns with the rainfall data in the city over 100 years.

He discovered that as per the data, there is more than enough rainfall in the city. He had to make the rainfall over 60-70 days last for 365 days.

“I built a series of RWH tanks that could store almost 45,000 litres of water to tide over these 100-odd days. Also, to ensure that a motor was not needed, I stored the water on the rooftop to avoid it being sent down and pumped up again,” explains Shivakumar.

Each tank has been fitted with an innovative filter device that has been built and patented by the scientist.

Called Pop-Up Filter, the device uses a simple silver sheet to remove all impurities from the collected rainwater before channelling it around the house. It can be vertically installed on the walls of small buildings (for bigger buildings, Shivakumar has designed a ‘First Flush Lock and Diverter’ that performs the same function).

He has also dug percolation pits in the garden around his house that help in the direct recharge of the groundwater table.

Over the past three decades, the groundwater table around Shivakumar’s house ‘Sourabha’ rose from the depths of 200 ft to around 5-10 feet!

He also recycles greywater at his home — the water from the washing machine is used for flushing toilets while waste kitchen water is used for gardening.

Shivakumar has designed and implemented hundreds of RWH projects in Bengaluru, including at Vidhana Soudha, the Karnataka High Court, corporate offices (such as Arvind Mills and Intel India), along with several housing societies.

He has also trained Bangalore Water Supply and Sewerage Board (BWSSB) plumbers, building contractors and architects in the integration of RWH in construction. He was instrumental in introducing the porous city concept in the city.

The RWH expert also played a key role in getting the Karnataka government to pass an amendment to the (BWSSB) Act that made rainwater harvesting compulsory for houses and offices with an area greater than 2,400 sq ft in the core of Bengaluru.

He has been honoured with several awards like central government’s National Innovation Award, Karnataka government’s Amulya award and more.

A vociferous proponent of RWH, he has not paid a water bill for 28 years. It was only last year that he got a water connection due to abysmal rains. Still, he hasn’t used that water yet, he says happily.

“Nature holds the answers to the problem of urban water scarcity. We must catch the rain wherever and whenever it falls,” says Shivakumar.