Supply of Water to Consumers | Distribution System | Water Engineering

The water can be supplied to the consumers by the following two system: 1. Continuous System 2. Intermittent System.

1. Continuous System:

This is the best system and the water is supplied for all the twenty four hours. This system is possible when there is adequate quantity of water for supply. In this system sample water is always available for fire-fighting and due to continuous circulation water always remains fresh.

2. Intermittent System:

If plenty of water is not available, the supply of water is divided into zones and each zone is supplied with water for the fixed hours in a day. As the water is supplied after intervals, it is called intermittent system.

This system should not be continued on long term policy due to the following disadvantages:

(i) The consumers have to store water for non-supply hours which is likely to get contaminated. Some consumers may not have sufficient storage tanks, which may lead to insanitary conditions.

(ii) If it gets fire in non-supply hours no water is available and it may cause huge damage before the supply could be turned on.

(iii) It has been observed that consumers leave their taps open for every time, which causes much wastage of water.

(iv) If more storage of water is done in non-supply period, it is thrown off causing wastage of water.

(v) Bigger diameters of pipes are required to supply the water for the full day in a very short period.

(vi) During non-supply period, the pressures in the water mains fall below the atmospheric pressure, thus creating partial vacuum, which may induce suction of soil particles in the pipes through joints. If the sewer line is laid along the water mains, it may cause contamination of the water in this way.

(vii) Large number of valves will be required in maintaining this system, because they are to be properly operated while closing or introducing the supply of water.

(viii) This system causes great inconvenience to the consumers, as they have to remain alert to collect the water during supply periods, especially from street stand post or tap, where long queue is formed for this. In some cases it becomes the main cause of struggle in the locality.

Inspite of number of disadvantages, this system is usually adopted in most of the cities and towns of India. This system though does not save water as required, but in this system the water can be supplied in the high level localities with adequate pressure, by dividing the city in zones. The repair work can be easily done in the non-supply hours.