Water crises are often equated with declining supplies in reservoirs that provide water to the city, or with the unavailability of resources. However, many times, conservation measures are more focussed on reducing usage of water, rather than dealing with a critical issue – tackling the loss of water through leakage.
Leaks cannot be brushed away as trivial, as a drip per second from a tap could mean that nearly 34 litres of water are wasted in a day.
The increasing demand for water following rapid urbanisation is not the only challenge that many Asian cities face today. ‘Unaccounted for Water’, which is the amount of water lost before it reaches consumers, is a common challenge that cities encounter.
The high leakage rate in many cities dominated discussions by leaders from across the world who had gathered at the World Cities Summit held in Singapore earlier this month. While investing in the creation of new sources to expand supply is essential, cutting down unaccounted-for water also needs to be given priority to sustain the increase of water production.
I was surprised when Bindu N.Lohani told me that nearly 20-30 per cent of unaccounted-for water is common in many Indian cities. Lohani, vice-president, (Knowledge Management and Sustainable Development) of Asian Development Bank said that plugging leakages in the supply system would go a long way to providing access to clean water to thousands of people.
The leakage rate in cities such as Delhi and Bangalore is nearly 40 per cent, almost double the average rate in other Asian cities. Asian Green City Index, a research project by Economist Intelligence Unit, brought out at the summit, also confirmed the high rate of water leakage in cities.
Leakage in Chennai, according to Metrowater, is 11-12 per cent of the 830 million litres supplied daily. While this figure is comforting relatively speaking, we have to realise that the city’s consumption rate – 135-140 litres per person per day – is also lesser than that of other cities.
Much of the loss in water supplied in the city is due to leaks in pipelines linking the water mains with houses. Some of it wasted when water is transmitted from one facility to another or when it is distributed. However, Chennai Metrowater woke up to the issue of water loss recently, and managed to reduce leakage in consumer-supply pipes and metered the flow of water in some of its treatment facilities.
While illegal connections are said to be negligible, much needs to be done to in terms of replacing old lines, particularly in north Chennai, installing flow meters in water mains to detect leakages and using technology to prevent losses.
Several cities that have reduced water leakage by adopting good practices in urban water management show the way. Jamshedpur, which managed to reduce unaccounted-for water from 36 per cent to less than 10 per cent, has teams regularly going on ‘walk-through surveys’ along the supply network with leak detection equipment to track the exact location of underground leakage. Singapore, which has a low leakage rate of four per cent, prohibited illegal connections, and also enforced stringent supervision of pipe-laying work. Consumers are also challenged to reduce daily consumption by 10 litres to encourage community participation.
While the government definitely has a duty towards reducing water leakage to a minimum, residents too, could contribute by ensuring that leaks from a hand pump don’t go unnoticed.
