RR Sivaram’s Eco Bloc system captures up to 96% of rainwater through built-in harvesting structures spaced every 15 metres, and costs 15 to 20% less than conventional stormwater infrastructure
In India, every monsoon season plays out the same way. Roads continue flooding, and traffic comes to a halt, because millions of liters of precious rainwater end up in the drain, only to disappear before anyone can use it. And just a few months later, the same cities suffer from water scarcity. RR Sivaram saw this vicious cycle and realized that the problem was actually the drain itself and that it should be redesigned.
What Sparked the Idea
The key moment came from two events in Chennai that were on opposite sides of the same problem. The floods in 2015 revealed how rapidly urban infrastructure can collapse during heavy rainstorms. And the severe drought of 2019 explained what happened to all that lost water. Sivaram addressed the problem by developing a system that treated stormwater not as a problem but as a useful resource.
How Eco Bloc Works
Built from recycled plastic, Eco Bloc replaces conventional concrete stormwater drains with a system that includes built-in rainwater-harvesting structures spaced every 15 metres along the drain’s length. Its honeycomb design captures up to 96% of incoming rainwater, which then passes through a four-stage filtration system that removes silt and road debris before the clean water is directed into modular underground storage tanks installed beneath roads and parks.
The tanks produced work under certain urban conditions. They withstand loads of up to 60 tons, have a lifespan of over 50 years, and are designed to be reused, recycled, and relocated as urban life evolves.
What It Has Delivered
The first installation of Eco Blocs was completed in Chennai in 2020, bringing back the temple tank that had been empty for 12 years. Since then, more than 5,000 installations have been completed across India, harvesting more than 50 million liters of water. Moreover, the total cost is much lower than that of usual stormwater drains.
