Founded in 2009, Enviro Infra Engineers Limited (EIEL) is a leading Indian company specialising in the design, construction, operation, and maintenance of water and wastewater treatment plants (WWTPs) and water supply scheme projects (WSSPs) for government authorities. The portfolio extends to Sewage Treatment Plants (STPs), Common Effluent Treatment Plants (CETPs), sewerage systems, and Water Treatment Plants (WTPs) with associated infrastructure such as pumping stations and pipelines. Operations now span eight states, with 28 WWTPs and WSSPs completed - 22 of those with capacities of 10 MLD and above. Advanced technologies in use include Sequential Batch Reactors (SBR), Ultrafiltration (UF), Reverse Osmosis (RO), and Multiple Vapor Recompression (MVR) for Zero Liquid Discharge (ZLD) compliance, all aimed at sustainable infrastructure.