The first of these processes is the collection of surface water. The raw water is stored in Ndakaini, Sasumua and Ruiru Dams from where it is released for treatment. Storage of raw water is an important step which helps in the natural elimination of harmful bacteria. The bacteria in the water die as a result of exposure to sunlight and because of the sudden change of environment. In case the raw water is contaminated from source, storage also helps in diluting the concentration of the contaminant.
The first of these processes is the collection of surface water. |