The Asian Development Bank (ADB) has approved a $230 million loan to modernise and expand Chennai's water supply and sanitation infrastructure, a project expected to benefit about 4.5 million residents across the Greater Chennai area.

The project includes the construction of more than 170 km of water supply and sewer pipelines, the upgrade of seven water pumping stations and 38 sewer pumping stations, and measures to strengthen the management of water utility assets and operations through performance-based contracts, the ADB said on Friday.

The multilateral lender said Chennai will become the first Indian city to implement a comprehensive ring-main water distribution system, a closed-loop network designed to maintain balanced water pressure and improve the efficient delivery of water across service areas.