Health Hygiene & Sanitation

Lesson 24 : Special Treatment Of Water And Their Health Implications

Distribution Of Water

There are two main systems of water distribution:

• Intermittent supply – water is delivered only during fixed hours.
• Continuous supply – availability of flowing water for 24 hrs.

The disadvantages of the intermittent system are

• The pipes may be empty during emergency
• Water has to be stored in containers which may not be clean always. The safe water is likely to be rendered unsafe through improper storage
• When the pipes are empty, there is negative pressure, back-siphoning, bacteria and foul gases may be sucked in through leaky joints.
• A number of outbreaks of typhoid and relapsing fever and other diseases have been recorded due to the contamination of water in the intermittent piped water supplies.

Continuous water supply is desirable, although it may result in wastage through misuse. A WHO Expert Committee (1965) strongly recommended that intermittent and low pressure service should be avoided