Chief Minister M.K. Stalin on Monday laid the foundation stone for the Mamallan reservoir — envisioned as Chennai’s sixth major water storage structure — at Nemmeli in Chengalpattu district, underscoring the government’s focus on long-term water security.The Rs 342.60-crore reservoir project, coming up in the Kovalam sub-basin between Thiruporur and Thirukazhukundram along the East Coast Road (ECR), is expected to play a critical role in meeting the drinking water needs of Chennai’s rapidly growing suburbs. Once completed, it will store an estimated 2.25 thousand million cubic feet (TMC) of water annually and supply around 170 million litres per day to the city and surrounding areas.
Stalin explained that the reservoir has been named Mamallan in tribute to the famed Pallava ruler Narasimhavarman I, popularly known as Mamallan, who built the historic port city of Mamallapuram, now a UNESCO World Heritage site.
The new facility is expected to benefit nearly 13 lakh people in localities including Sholinganallur, Medavakkam, Pallikaranai, Siruseri, Kelambakkam, Tiruporur and Mamallapuram by augmenting water supply and reducing pressure on existing reservoirs. The project will also help enhance groundwater recharge and reduce seawater intrusion in coastal areas.
To address concerns raised by local fishing communities, Stalin assured that fishing rights would be granted to residents near the reservoir area as part of efforts to safeguard their livelihoods. A 15-km stretch of the Buckingham Canal in the region will be renovated, further supporting both water management and community needs.
Spread over more than 5,160 acres with a total catchment area exceeding 41,400 hectares, the Mamallan reservoir represents a significant addition to Chennai’s water infrastructure, which currently relies on a network of reservoirs including Poondi, Puzhal, Chembarambakkam, Cholavaram and Kannankottai-Thervoy Kandigai, as well as supplemental sources such as Veeranam lake and desalination plants.
The foundation-stone laying ceremony was attended by ministers E.V. Velu and T.M. Anbarasan, Chief Secretary N. Muruganandam, and Water Resources Department Secretary J. Jayakanthan, among other officials.
The project, which has already secured Coastal Regulation Zone clearance, reflects the state government’s strategy to strengthen long-term water resilience amid urban expansion and climatic challenges.