Providing Drinking Water

Generally, water is collected at a source (river, lake, spring) and put into a large tank. From this tank, the untreated water is either pumped or flows by gravity to a treatment facility where it is treated to make sure it is suitable for drinking. The treated water is pumped to very large concrete tanks called reservoirs, usually located on hills where the water is stored for 1 to 2 days and distributed through a pipe network called a distribution system to the users (homes, offices, industries etc.) Fire hydrants are placed in the distribution system to ensure we can have plenty of easy access to the water in the event of a fire.

The quality of water is monitored at all stages of collection, treatment and distribution. If the water source ever becomes polluted, then water is not abstracted from this source until the pollution has been removed.

The amount of treatment depends on the initial quality of the water. Water abstracted from rivers and lakes require more treatment than water abstracted from springs.

Treatment involves the addition of chlorine in order to stop the unwanted effects of harmful bacteria. It also involves filtration, flocculation and settlement. Filtration removes larger solids such as leaves, twigs etc from the water while the floculation and settlement processes remove smaller solids from the water.

Chemicals may be added to ensure the ph is neutral i.e. the water is not too acidic or alkaline.

In larger schemes, fluorine is added to help with dental health.