Water discolouration or the yellowish water issue experienced by many parts of the country is among other things caused by inconsistent raw water quality with a high level of 'yellowish' discolouration and low water "pH' or Potential Hydrogen. In its media release, the Public Works Department, PWD sad the 'turbidity' of raw river water often changes according to the weather situation.

Drought during the hot season and floods during the rainy season are among factors that cause the visible quality change. Besides that heavy rains or water which has been stagnant for long periods in water catchment areas can also cause the changes or increase in mineral contents composition of raw water.

The long stagnant water flows into the river causing smelly raw water. This requires more thorough treatment in terms of chemical doses used in addressing the quality problem. Apart from calcium carbonate and aluminium sulphate which are the usual chemical used in water treatment, additional chemicals are also used to help the congealing process of flocs in sedimentation tanks such as "Sodium Aluminate" and "Polymer".

The PWD also strives to control and ensure the quality of water supply reaches the parameter of the World Health Organisation, W.H.O. Standard guideline for clean water. Laboratory tests for the 'pH' level, turbidity, "chlorine" and others will be carried out every two hours, everyday.

With the 'flocs' averaging more than usual, sedimentation and filtration require more frequent cleaning and this decreases clean water production at water plants. The PWD is also trying to address the problem by implementing operational work such as cleaning water reservoir tanks and balancing the flow of water into them. Apart from that repair the Bukit Barun Water Treatment Plan Phases 4 and 5 are still under repair and still cannot be fully used.

A new project has also been approved, namely the construction of Stage 8 Water Treatment Plant Stage which has the capacity to produce more than 120 litres of clean water daily. Apart from increasing clean water supply for Brunei Muara and Tutong Districts, the plant will also assist other plants if required.

Members of the public, especially those who own house water tanks and water filters are advised to to ensure they are always clean by carrying out routine 'flushing' and 'backwashing'. Water tanks and filters that have not been cleaned for long periods can cause discolouration of water used in the house even though supply from outside is clean. For water supply from tanker Lorries or complaints on clean water supply call Talian Darussalam 123.

Source: Radio Television Brunei