For Chennai, long accustomed to counting water supplies by the hour and worried about summer shortages, water stress is a subject of both concern and humor. The city’s experiment with 24-hour uninterrupted and equitable piped water supply – aided by a ring main distribution system, a looped pipeline network connecting all sources – signals a move away from intermittent distribution and short-term water management.
Chennai is sustained by its water sumps. This perpetuates the myth that piped supply is continuous, when in fact it is not. Even key areas get only intermittent supply, making the Adyar area test an important experiment that could change the city’s water distribution strategy. There are preparations to start continuous piped supply in this area at the time of easing of daily water distribution in the city this year. Chennai’s major reservoirs have better storage than ever in recent years. This allows planners to focus on improving reliability rather than managing scarce resources and rationing.
Calibrated Water Release
The Water Resources Department’s calibrated water release strategy – taking into account rainfall, flow and demand – has helped optimize the storage of the reservoirs, supported by continuous transfer of water from the Krishna River in Andhra Pradesh and the Veeranam Tank in Cuddalore district. At the heart of the ₹271.50 crore pilot project in Zone XIII is an effort to break Chennai’s long-standing dependence on time-bound supply schedules, which leads to uneven distribution across zones. This initiative is in line with the vision of the Union Ministry of Housing and Urban Affairs 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 to appoint a concessionaire to upgrade the Pallipattu and Thiruvanmiyur water distribution stations. The upgrade, to be completed over two years, will include improvements to distribution pipelines, automated controls and SCADA-enabled real-time monitoring. These measures are important to maintain a continuous, metered supply and stable pressure to prevent pipeline contamination. The water agency has entered into an agreement with Odisha Jal Corporation to work as a project management consultant to implement the ‘Drink from Tap Mission’ in Puri.
According to the World Bank, round-the-clock supply is being implemented, or is under implementation, in several other states, including Karnataka, Madhya Pradesh, Andhra Pradesh, Punjab and Maharashtra. In Tamil Nadu, pilot projects are underway in some other places including Coimbatore and Tiruchi. However, Chennai residents view the promise of uninterrupted supplies with cautious optimism. The city has long relied on diverse sources – groundwater and metrowater supplies, tankers and increasingly packaged drinking water – to bridge persistent shortfalls. 2-3 crore liters of packaged water is consumed daily in and around Chennai.
Welcoming the move, residents emphasize the delivery of clean water and accountable, sustainable supply. In Adyar, residents say the continuous supply will help conserve groundwater reserves. Chennai’s average groundwater level dropped marginally by 0.70 meters in December 2025 compared to the previous year, as the northeast monsoon remained dry for a longer period this season.
R., a resident of Besant Nagar for more than five decades. Krishna Mohan points to the pressure that rapid urbanization has put on groundwater levels. “Living here since 1972, I have seen once abundant coastal aquifers come under severe stress due to overexploitation. Water-metering and regulation of borewells are important to reduce water wastage, plan for depletion and protect what remains of coastal aquifers.”
old pipelines
Concerns over aging infrastructure and water quality remain even in core parts of the city. Although complaints of supply disruptions have reduced, problems caused by sewage pollution and old pipelines pose a serious threat. Kodambakkam Subramaniam Nagar Residents Welfare Association Secretary S. Gopi says that unless the risks of contamination are addressed, efforts to improve supply will fall short. “Our locality has faced several cases of sewage mixing with drinking water in the four years since the construction of storm water drains. Improperly aligned pipelines have led to reduced water pressure in end areas.”
Residents say that before moving to the next phase of its strategy and installing water meters, Metrowater must ensure that households get clean water. If continuous supply is to be successful, it is necessary to replace old lines and prevent sewage from flowing into storm water drains.
In its guidelines for uninterrupted supply, the Ministry of Housing and Urban Affairs has highlighted the importance of uninterrupted pressurized supply to improve people’s health and deteriorating water quality. It has been noted that contaminants may enter pipelines through leakage in the intermittent water supply during non-supply hours due to the vacuum developed in the pipeline.
Source enrichment is no longer a major hurdle. CMWSSB Managing Director TG Vinay says the focus has now shifted to equitable supply, demand management and increased use of recycled water to create water resilience.
Officials say the upcoming fourth desalination plant at Perur with a capacity of 400 million liters per day, the recently commissioned second line from the Chembarambakkam treatment plant to increase distribution, the new reservoir at Thiruporur and expansion of recycled water capacity will strengthen Chennai’s water supply base. Metrowater in its master plan has estimated that water demand will increase to 1,762 MLD by 2057.
Over the next five to 10 years, Chennai can leave behind its annual fear of monsoon failure and move towards reliable, rational water supply. A network of decentralized water treatment plants including Perungudi, Kolathur and Mogappair are being built to meet the increasing demand. The drinking water potential of lakes like Porur and Ayanambakkam is being exploited, says Mr Vinay. The major challenge is the aging water distribution infrastructure and this will be addressed in phases.
leak control
In Adyar area, the entire distribution network will be divided into district-metered areas by fixing limit valves and flow meters to control leaks, reduce non-revenue water supply and balance the pressure in the entire network.
The pilot project in core areas including two wards of Valasaravakkam was started as per the orders of Japan International Cooperation Agency, which funds the Perur desalination project. SMEC International, the project management consultant for the new desalination plant, is preparing a detailed project report for other areas covering the main areas including Tondiarpet, Perambur and Teynampet.
Residents of Manali New Town say the quality of piped water supply 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. But households are largely dependent on Metrowater’s daily three-hour supply.
“As more apartments are built in the area, the demand for water will increase. Metering will help in estimating consumption, but Metrowater should create awareness to allay fears of over-billing when the system switches to metered tariff,” says Mr Isaimozhi.
Metrowater officials say uninterrupted water supply will be expanded to all core areas in phases. The water agency is taking parallel initiatives to achieve its goal of transforming Chennai into a water-secure city. The 98 kilometer long circular pipeline, or Ring Main Distribution System, will interconnect all water sources with distribution points to ensure availability of water to all areas even if one source fails. The entire water distribution network will improve after the implementation of the ₹3,108.55 crore Ring Main Distribution System and 24/7 Water Supply projects.
As far as demand is concerned, Metrowater is targeting one lakh water-intensive users to install smart water meters, and metering will be expanded to domestic consumers in phases. Officials said installing electromagnetic flow meters with Internet of Things (IoT) technology in water treatment and distribution networks will go a long way in identifying leaks and reducing non-revenue water supply.
sewage management
Water experts have called for the creation of an integrated water management authority on the lines of the Chennai Unified Metropolitan Transport Authority, empowered to manage fresh and recycled and storm water in an integrated manner. They argue that the fragmented approach often hinders effective planning and accountability.
B Sakthivel, a hydrologist and consultant who works with government agencies, says lasting improvements in drinking water sources and infrastructure will be possible only if the entire sewage loop – production, collection and treatment – is closed. The State Government should also set key performance indicators for sewerage management for utilities to ensure measurable results.
