CAUSES OF WATER CONTAMINATION

The principal problems leading to contamination of stored water are:

1.    Light transmission. Growth of algae will occur if light is permitted to enter the tank, this will adversely affect the water taste, and can lead to disease such as gastroenteritis.

2.    Rough internal surface of the tank. The cavities in the internal surface allow bacteria to nest and proliferate. Bacteria protect itself from the effect of Chlorine by creating a bio-film. Chlorinated water also loses its bactericidal properties after a few hours, if not constantly replenished. At one point in time, this bio-film breaks and the bacteria is killed by the chlorine. The bio-product in presence with the algae and Chlorine, will produce Tri-Halo methane. Studies at John Hopkins and Stanford universities show that Tri-Halo methane is a potential carcinogenic agent.

3.    Incomplete or poor drainage. If the tank design does not ensure complete free-flow drainage, a build-up of residual static water will result. This will harbor contaminants referred to above, as well as particles from internal corrosion or introduced externally.