Beyond water scarcity: Efficiency, conservation and Delhi’s path forward

Across the world, water demand continues to rise even as water resources become increasingly stressed. Global assessments under the United Nations-mandated Sustainable Development Goal 6 show that billions of people still lack access to safely managed drinking water and sanitation, even as overall water withdrawals have increased. This paradox makes clear that water scarcity is not merely about physical availability. It is equally about how water is extracted, distributed, used, treated and returned to nature.

Climate change is worsening this imbalance. Shifting rainfall patterns, more frequent droughts and floods, rising temperatures and higher evaporation rates are shrinking surface water availability and reducing groundwater recharge. In many regions, climate stress is exposing long-standing failures in water governance.

India experiences these pressures far more sharply. The country supports nearly 18 per cent of the global population but has access to only about 4 per cent of the world’s freshwater. Rapid urbanisation, rising consumption and increasing climate variability have placed immense stress on rivers and aquifers. National assessments show that per-capita water availability has been declining steadily and is projected to fall further, pushing India closer to chronic water stress.

In this context, the conventional response of creating new supply through dams, canals or deeper borewells is neither environmentally viable nor economically sustainable. Improving water-use efficiency and conservation is no longer optional; it is central to India’s water security.

Water-use efficiency & India’s policy framework

India does recognise the importance of water-use efficiency at the policy level. The National Water Mission under the National Action Plan on Climate Change aims to improve water-use efficiency by 20 per cent across sectors.This reflects that supply expansion alone cannot address growing demand.

Guidelines issued by the Union Ministry of Jal Shakti (water resources) stress that cities must first reduce losses, improve measurement and manage demand before developing new water sources. The Centre for Science and Environment’s (CSE) Water Efficiency and Conservation (WEC) Practitioner’s Guide expands this definition of efficiency beyond simply “using less water”.

It includes reducing leakage, improving reuse, harvesting rainwater and managing demand through better planning and pricing. Crucially, it highlights the need for baseline data, clear targets and regular monitoring to ensure that efficiency gains are real and measurable.

At the national level, the Bureau of Water Use Efficiency has been set up under the National Water Mission to develop water conservation codes, efficiency standards and guidance for water-using fixtures and equipment. While this marks progress, BIS-aligned standards and urban conservation codes are still being finalised. As a result, mandatory enforcement across cities has yet to begin.

Some cities, including Delhi, have initiated steps towards better measurement and demand management. In the NDMC area, a Rs 31-crore project to install over 20,000 smart water meters has been approved to improve billing accuracy, leak detection and monitoring of consumption, with completion expected by 2026. Smart-meter-based billing reforms have also been proposed under the Delhi Jal Board.

However, there is still no publicly reported evidence of a citywide reduction in non-revenue water. Smart metering, network zoning and leak-control systems have not been implemented across the entire city. This gap between policy intent and on-ground outcomes explains why Delhi’s water losses remain extremely high despite multiple initiatives.

Delhi’s water situation: Stress, losses, pollution

Delhi’s water crisis is shaped by three interconnected problems: high losses, excessive consumption and poor wastewater management.

The city depends heavily on water imported from the Yamuna and Ganga basins, yet many neighbourhoods face irregular and unreliable supply. A major reason is that a large share of treated water never reaches users. The Economic Survey of Delhi 2023–24 estimates that around 58 per cent of the city’s water is non-revenue water, lost through leaks, illegal connections and poor metering. Media reports place losses at around 55 per cent, largely due to ageing pipelines and weak system control.

In effect, more than half the water Delhi treats disappears before it can be used, creating an artificial scarcity.

At the same time, over-consumption is widespread in affluent colonies, hotels, offices and government buildings, where water use far exceeds the national service norm of 135 litres per person per day. Large volumes are spent on watering lawns, washing vehicles, cooling and other non-essential uses, as documented in CSE’s water-efficiency and fixture-use studies.

Low water tariffs and weak metering provide little incentive to conserve. This creates deep inequality wherein some parts of the city waste water, while poorer neighbourhoods depend on tankers and endure daily shortages.

Wastewater management is another critical failure. Delhi generates around 3,600 million litres per day of sewage. While the city has 37 sewage treatment plants with an installed capacity of 3,474 MLD, only about 2,955 MLD is actually treated. Even more worrying is treatment quality. Only 23 plants meet pollution standards; the rest discharge inadequately treated effluent.

As a result, around 641 MLD of untreated sewage enters the Yamuna every day, severely polluting the river and undermining its ability to serve as a water source.

Although Delhi has large infrastructure, huge amounts of water are lost, poorly treated or discharged into the river instead of being reused, thereby explaining why water stress continues.

Delhi’s urban water situation

This wastewater represents a significant untapped resource, as illustrated in CSE's Waste-to-Worth report. If properly treated, it could meet large non-potable demands such as construction, industry, power plants and urban landscaping, reducing pressure on rivers and groundwater while enabling a circular water economy.

Challenges & possible solutions

Delhi’s first and most urgent challenge is its extremely high non-revenue water. When more than half the supply is lost, new water projects will not resolve shortages. Reducing losses requires systematic water audits, district-metered areas, pressure management and active leak detection, as the WEC Practitioner's Guide recommends. Universal metering and accurate billing are equally critical for utilities to understand and manage their networks.

The second challenge is poor wastewater reuse. Many treatment plants fail to meet standards, and the city lacks dedicated pipelines to distribute treated water. The National Framework on Safe Reuse of Treated Water and the Waste-to-Worth report both recommend using treated wastewater for non-potable purposes such as construction, industry, landscaping and power plants. Delhi must therefore upgrade treatment quality and invest in separate conveyance systems for reuse.

The third challenge is over-consumption. This can be addressed through universal metering, progressive tariffs for high users and widespread adoption of water-efficient fixtures. Evidence shows that efficient taps and toilets, rainwater harvesting and greywater reuse can reduce household water use by 30-50 per cent without compromising comfort.

Improving sewage treatment and reuse would also reduce pollution loads in the Yamuna and curb groundwater extraction, strengthening long-term water security.