Transition from intermittent to 24/7: A success story from New Delhi
Till early 2016, before the beginning of continuous water supply in Navjeevan Vihar, the area was receiving 1.20 MLD of water every day. With a population of 1850, this translated into 650 liters of water per person per day. A considerable quantity, yet consumers complained of short supply.
So where was all this water going? Investigations revealed that supply at high pressure in short intervals was feeding leaks in the distribution network. High pressure meant higher leakages, with almost 35% of water was getting lost, every day.
The area is being fed by supply from Sonia Vihar Water Treatment Plant, which treats water to established international standard. Yet, there were complaints of substandard water quality and the consumers had to deploy expensive filtration equipment at their end.
Due to zero pressure in the network during non-supply intervals, the contaminants rushed in through the very leaks that lost water during supply intervals.
As a pilot study, it was decided to isolate or ring-fence the supply network for Navjeevan Vihar, closing all inlets into the network, except one which was pressure regulated and metered. It was then decided to maintain a minimum pressure in the network at all times. This helped in two ways.
Constant pressurization reduced the entry of contaminants, and the consumption patterns of the area could be monitored. Knowing the consumption patterns, the pressure in the network was regulated as per the demand, instead of a wasteful high pressure earlier.
Constant pressurization in the network also facilitated the detection of leaks. For this, a cutting edge Helium based leak detection technique was adopted. This technique could detect and pinpoint leaks with 100% accuracy. Leaks were mended, supply lines rerouted or replaced wherever necessary.
The network was ready for 24x7 water supply, with no losses and no contamination in the network.
But this was not the end of leakage losses or contamination. The private underground or overhead storage built by the residents over the years played the spoilsport. A large scale community engagement programs were organized to educate the consumers.
Convinced residents now have access to quality drinking water on tap, 24 hours a day, and their consumption bills are also much lower since there are no losses in their premise storage and handling.
The loop of continuous pressurised water supply is now complete. There is 24x7 water supply in the area. The water quality is much better.