For Chennai, long accustomed to counting water supplies by the hour and worried about shortages in summer, water stress is both a matter of concern and dark humor. The city’s experiment with a 24-hour uninterrupted and uniform piped water supply – supported by a circular distribution, a looped pipe network connecting all sources – signals a move away from intermittent distribution and short-term water management.
Chennai is sustained by its water wells. This perpetuates the myth that pipeline supply is continuous, when in fact it is not. Even key areas receive only intermittent supplies, making the trial in the Adyar zone a key experiment that can change the city’s water distribution strategy. Continuous piped supply in this zone is to be started this year at a time of comfort in the city’s daily water supply. The main reservoirs of Chennai have had better storage in recent years than ever before. This gives schedulers room to focus on improving reliability rather than managing scarce resources and allocations.
Calibrated water output
The water resources department’s calibrated water release strategy – taking into account rainfall, inflow and demand – has helped optimize reservoir storage, supported by constant pumping of water from the Krishna River in Andhra Pradesh and from Veeranam Reservoir in Cuddalore district. The core of the ₹271.50 crore pilot project in Zone XIII is an attempt to break Chennai’s long-standing dependence on time-bound delivery schedules, which has led to uneven distribution across areas. The initiative is in line with the Union Ministry of Housing and Urban Affairs’ vision to make Indian cities water-secure through the Atal Mission for Rejuvenation and Urban Transformation (AMRUT) 2.0.
The Chennai Metropolitan Water Supply and Sewerage Board (CMWSSB) is finalizing tenders for the appointment of a concessionaire for the upgradation of the Pallipattu and Thiruvanmiyur water distribution stations. The upgrade, due to be completed in two years, will include improvements to distribution pipelines, automated control and real-time monitoring with SCADA support. These measures are critical for continuous, metered delivery and for maintaining a stable pressure to prevent pipeline contamination. The Water Management Agency has entered into an agreement with the Water Corporation of Odisha, which has implemented ‘Tap Drink’ in Puri, to serve as a project management consultant.
According to the World Bank, uninterrupted supply is being implemented or underway in various other states, including Karnataka, Madhya Pradesh, Andhra Pradesh, Punjab and Maharashtra. In Tamil Nadu, pilot projects are underway at several other locations, including Coimbatore and Tiruchi. However, the people of Chennai see the promise of uninterrupted supply with cautious optimism. The city has long relied on a patchwork of resources — groundwater and Metrowater supplies, tankers and increasingly bottled drinking water — to bridge persistent gaps. Chennai and its environs consume 2-3 million liters of bottled water per day.
Residents welcome the move and insist on clean water distribution and responsible and sustainable supplies. Residents of Adyar say the uninterrupted supply will help save groundwater supplies. The average groundwater level in Chennai has marginally decreased by 0.70 meters in December 2025 compared to the previous year as the northeast monsoon this season has been marked by prolonged dry spells.
R. Krishna Mohan, a resident of Besant Nagar for more than five decades, points out the pressure that rapid urbanization has caused on the groundwater table. “Having lived here since 1972, I’ve seen a once-abundant coastal aquifer come under severe stress due to over-mining. Water metering and well regulation are critical to reducing waste, planning for shortages and protecting what’s left of the coastal aquifer,” he says.
Aging pipes
Concerns about aging infrastructure and water quality persist even in the core parts of the city. Although complaints of supply interruptions have fallen, sewage pollution and problems caused by old pipelines pose a serious threat. S. Gopi, secretary of the Kodambakkam Subramanian Nagar Residents’ Welfare Association, says that unless the risks of contamination are addressed, efforts to improve supply will fail. “Our site has faced several incidents of sewage mixing with drinking water in the four years since the stormwater drains were built. Misaligned pipes have caused a drop in water pressure in the end areas.”
Before moving to the next phase of its strategy and installing water meters, Metrowater needs to ensure households receive clean water, residents say. Replacing old lines and preventing sewage from entering stormwater drains are essential if continuous supply is to be successful.
The Ministry of Housing and Urban Affairs, in its guidelines for continuous supply, has highlighted the importance of continuous pressurized supply for human health and improving deteriorating water quality. She found that contaminants can enter the pipes through leaks in the intermittent water supply during hours when there is no supply due to a vacuum created in the pipes.
Resource expansion is no longer a major limitation. The focus has shifted to equitable supply, demand management and increasing use of recycled water to build water resilience, says CMWSSB CEO TG Vinay.
The upcoming fourth desalination plant at Peruru with a capacity of 400 million liters per day, the recently commissioned second line from the Chembarambakkam treatment plant to improve distribution, a new reservoir at Thiruporur and expansion of recycled water capacity will strengthen Chennai’s water supply base, officials say. In its master plan, Metrowater estimates that water demand is likely to increase to 1,762 billion cubic meters by 2057.
In the next five to ten years, Chennai can shed its annual fear of monsoon failure and switch to a reliable, rationalized water supply. A network of decentralized water treatment plants, including those at Perungudi, Kolathur and Mogappair, are being built to meet the growing demand. The potable water potential of lakes like Porur and Ayanambakkam is being tapped, says Mr. Vinay. The main problem is the aging infrastructure of water distribution, which will be solved gradually.
Leakage check
In Adyar zone, the entire distribution network will be divided into district metered areas by fixing boundary valves and flow meters to control leakages, reduce non-revenue water supply and equalize pressure in the network.
The pilot project in key areas, including the two wards of Valasaravakkam, was launched in accordance with the mandates of the Japan International Cooperation Agency, which is funding the Peruru Desalination Project. SMEC International, the project management consultant for the new desalination plant, is preparing a detailed project report for the other zones covering key areas, including Tondiarpet, Perambur and Teynampet.
Residents of Manali New Town point out that the quality of water pipes has improved after new lines were laid six months ago. PK Thenkanal Isaimozhi of Manali New Town says groundwater is available at a depth of 30 feet. However, households largely rely on Metrowater’s three-hour daily supply.
“Water demand will increase as more apartments are added in the area. Metering will help estimate consumption, but Metrowater needs to create awareness to ease concerns about overcharging when the system switches to metered tariffs,” says Mr Isaimozhi.
Metrowater officials say 24/7 water supplies will be gradually extended to all key areas. The water management agency is undertaking parallel initiatives to achieve its goal of transforming Chennai into a water-secure city. The 98 km circular pipeline, or circular distribution system, will connect all water sources to distribution points to ensure water availability to all areas even in the event of a single source failure. The entire water distribution network will undergo renovation once the ₹ 3,108.55 crore circular main and 24/7 water supply projects are implemented.
On the demand side, Metrowater is targeting one million water-intensive users to install smart meters, and metering will gradually be extended to domestic consumers. Installing electromagnetic flow meters with Internet of Things (IoT) technology in the water treatment plant and distribution network would go a long way in identifying leaks and reducing unprofitable water supplies, officials said.
Sewerage
Water management experts have called for a unified water authority on the lines of the Chennai Unified Metropolitan Transport Authority, which would be empowered to manage fresh and recycled and storm water in an integrated manner. They argue that a fragmented approach often prevents effective planning and accountability.
B. Sakthivel, a hydrologist and consultant who works with government agencies, says lasting improvements to drinking water sources and infrastructure would only be possible if the entire sewage loop – production, collection and treatment – is closed. The state government must also establish key performance indicators for sewage management for utilities to ensure measurable results.
