When the borewells of his apartment complex dried up and water tankers became an expensive burden, Ganesh Shanbhag refused to sit back and watch. Instead of accepting water shortages as an unavoidable part of life, he decided to take action — and in doing so, he changed the way hundreds of Bengaluru apartments manage water.
Every morning, residents across the city wake up to the same struggle — empty water tanks, rising tanker prices, and the constant fear of running out of water. But what if the solution had been right above us all along, pouring down from the sky?
He saw potential in rainwater harvesting (RWH), a concept met with initial scepticism about its cost and complexity. Neighbours told him it was too expensive. Others dismissed it as ‘too technical.’ But Ganesh was determined to prove them wrong. Undeterred, he mobilised his community, and together, they designed and built an efficient rainwater harvesting system for an apartment complex with 100 flats—all for under Rs 3 lakh—transforming rainwater into potable water.
The results were immediate and impactful. In just two months, they saved Rs 2,00,000 in water bills and drastically reduced their dependence on costly tankers. At the same time, the system helped replenish the water table of the area.
Inspired by this success, Ganesh extended his expertise, helping over 300 Bengaluru communities implement similar RWH systems.
“I don’t charge any money for the work I do. The Rs 3,00,000 would be the investment to purchase necessary raw materials. I consider this a passion and would like to work with other apartments who have faced water crises and want to implement this,” he says. “In fact, my weekends are spent helping apartments facing water crises set up their own rainwater harvesting systems.”
How does it work?
- Catchment and Collection:
- The system utilises the extensive rooftop of the apartment complex as the primary catchment area.
- Precisely angled PVC gutters are installed along the roof’s perimeter, directing rainwater towards strategically placed downpipes.
- This meticulous arrangement ensures maximum water capture, even during moderate rainfall.
- Initial filtration:
- A critical component of the system is a ‘first flush’ mechanism. This diverts the initial surge of rainwater, which often carries accumulated dust, leaves, and other debris.
- After the first flush, the remaining rainwater passes through a coarse mesh filter, removing larger particles before entering the main filtration stage.
- Advanced filtration:
- Ganesh opted for disc filters, known for their efficiency and low maintenance requirements, rather than the more expensive pop-up filters.
- These filters, arranged in series, remove finer sediments and impurities, ensuring the collected water meets high-quality standards.
- The use of multi-layered mesh filters provides an extra level of security.
- Atmospheric ozone generators are installed to further purify the water.
- Storage and distribution:
- The filtered rainwater is then channelled into underground storage tanks, creating a reliable reserve.
- From these tanks, the water is pumped to overhead tanks, enabling gravity-fed distribution throughout the complex.
- Groundwater recharge:
- Ganesh’s system goes beyond mere storage.
- Excess rainwater is directed to a specially constructed recharge pit, replenishing the local aquifer and contributing to long-term water sustainability.
- This is especially crucial in an area where the water table has significantly declined.
How to reach Ganesh?
If you live in Bengaluru and want to break free from costly water tankers, reach out to Ganesh. He’s already helped over 300 communities — yours could be next. He is available at [email protected], or you can also connect with him via Facebook, LinkedIn, or Twitter.
Edited By Khushi Arora
