Bangalore, India


Simar Kohli, Tharun Kumar, Dr. E. Muralidharan


The EcoStp team created an eco-friendly approach to sewage treatment, inspired by the four chambers of a cow’s stomach.

This low-maintenance technology produces energy instead of consuming it, compared to conventional STPs which use energy-hogging motors, exhaust fans, pumps and blowers. This design doesn’t use chemicals to treat the sewage, but instead uses microorganisms, plants, and gravel to treat wastewater. With 93% of sewage untreated in India, the team is developing an economical and ecological solution that treats up to 1 million liters of sewage a day without needing to be connected to a power grid.

1. What is the problem you’re trying to solve and how does your design help?

My house is next to Bangalore’s Varthur Lake, which was once upon a time a beautiful lake. Now frequently it catches fire! There are 12 million people living in Bangalore – when half of the population flushes their toilets, their waste flows into lakes. Ninety-three percent of Indian sewage is untreated, but this is not only an issue limited to India. According to the UN, about 80% of the world’s wastewater is discharged into the environment without any treatment.

We investigated and found that the current sewage treatment technology is broken, as sewage treatment plants (STPs) hog lots of power and need dedicated operators. The solution we invented is a unique “zero power/zero operator” STP that disrupts the current model of using power-hogging motors to treat the sewage.

2. What makes your design different than previous or current approaches to the problem you’re trying to solve? What are the social, cultural, and/or environmental wins that your innovation provides?

ECOSTP is a nature-inspired solution with no moving parts. Unlike motor-based STP’s which are not sustainable, ECOSTP is a completely sustainable solution. The table below highlights few of the key differences:

ECOSTP Technology was discussed in 8th World Water Forum (Brasilia, 2018) and subsequently selected as a Best Practice case study for United Nations Sustainability Asia Pac report.

3. How did you apply lessons from living organisms to your design and what difference did that make?

We took inspiration from the cow’s stomach and used the following insights:
1. We replicated the chambers in a cow’s stomach and came up with civil engineering design which can be used for natural treatment of sewage.
2. We use anaerobic bacteria as the natural digester to break down the sludge content into treated water.
With the ECOSTP solution, we have already generated curiosity within the real estate developer community in India. They are excited to see an alternate solution to the motor based STP’s. Today we are working with around 14 builders to translate the findings to real time implementations. Bangalore lakes should not burn again.



Latest updates:

EcoSTP has been selected to be part of the AGNIi Innovation Showcase, an effort to showcase impressive solutions and technologies from Indian innovators as well as Indian research labs and academic institutions.

EcoStp addresses Sustainable Development Goals: Good Health and Well-Being (#3), Clean Water and Sanitation (#6), Decent Work and Economic Growth (#8), Industry, Innovation and Infrastructure (#9), Sustainable Cities and Communities (#11), Responsible Consumption and Production (#12), Life on Land (#15).