Guwahati: Researchers at Indian Institute of Technology Guwahati have developed a compact, low-energy wastewater treatment system that uses taro plants and a specially engineered “zig-zag flow” design to treat highly polluted swine wastewater.The system could offer a decentralised wastewater treatment option for livestock farms in rural and resource-constrained areas, IIT Guwahati said.Beyond piggery wastewater, the institute said the engineered wetland concept could be adapted for other decentralised agricultural and rural wastewater treatment applications, helping reduce nutrient pollution and improve environmental sustainability.The research was carried out by Waste Management Research Group in Department of Civil Engineering at IIT Guwahati. According to the researchers, the nature-based wastewater treatment system is intended to address a growing environmental challenge linked to expanding livestock production: the safe management of nutrient-rich and pathogen-laden piggery wastewater before it enters rivers, lakes and agricultural ecosystems.The study has been published in “Journal of Environmental Management”, an international peer-reviewed journal covering environmental sustainability, natural resource management and related areas. The paper was jointly authored by Monish Goswami, Sandip Ghosh and prof Ajay S Kalamdhad of IIT Guwahati.Prof Kalamdhad, of Department of Civil Engineering at IIT Guwahati, said the team wanted to make wastewater biologically safer for the environment, not only reduce pollution indicators.“We have demonstrated a compact and energy-efficient solution that could be adapted for decentralised livestock farms by engineering the movement of wastewater and combining it with the natural treatment abilities of plants and microorganisms,” he said.Monish Goswami, a PhD scholar at IIT Guwahati, said that unlike conventional constructed wetlands, where wastewater flows directly through the treatment bed, the new system uses “internal baffles” — built-in partitions — that force wastewater to move through a longer zig-zag pathway and undergo aerobic-anoxic transitions.He said this increases contact time between the wastewater, plant roots, beneficial microorganisms and gravel media, allowing multiple biological and chemical treatment processes to occur more efficiently.The study highlights how engineering interventions can improve the efficiency of natural wetland-based wastewater treatment systems. The swine wastewater used in the experiments was sourced from ICAR-National Research Centre on Pig in Assam as part of an R&D collaboration with IIT Guwahati.The research team’s next objective is to scale the laboratory-stage innovation for long-term field validation, with the aim of making sustainable, low-cost wastewater treatment accessible to decentralised livestock farming systems across India.
