Rand Water has started the final phase of wide scale infrastructure maintenance which is expected to run till the month end. The  maintenance, which began on 22 June, have resulted in extended cuts of water supply in large parts of Johannesburg. 

Water trucks have been dispatched to these areas as a temporary measure. Many people who cannot afford to buy drinking water rely solely on water provided by the trucks. But there have been concerns from residents on how safe it is to drink the water from these trucks.

Health-e News speaks with Professor Anja du Plessis, a senior lecturer and research specialist in Integrated Water Resource Management at the University of South Africa (UNISA), and Dr Jo Barnes, senior lecturer emeritus in the Department of Global Health at Stellenbosch University about the safety of drinking water from water trucks. 

Is the water from tankers safe to drink?

Barnes says the quality of water in such water tankers depends on a few factors, the most important of which is of course the quality of the water source from which it was filled. 

“There have been reports in the media of instances where water tankers were filled at nearby streams (i.e. unpurified). This is especially prone to happen in the case of tanker services put out to tender, and is done in attempts to save effort and money. Whenever a tanker has been filled with water of poor quality, the risk of waterborne diseases magnifies in the community receiving this water, since people also get ill from being infected by others who are already infected,” she says. 

She says another problem with water tankers is the way they are cleaned – if at all – between episodes of filling. According to the World Health Organisation the water in the tankers should be chlorinated to prevent the build-up of organic matter. 

“If contaminated water remains in the truck before refilling, especially overnight, then even the clean refill water will be contaminated in turn. Again, this is a crucial matter of oversight by the local authorities. If there is not even any possibility that the truck refilling system will ever be inspected, then those given such tasks will inevitably start cutting corners sooner or later,” she says. 

Norms and standards to be followed by water trucks

Du Plessis says the contractors supplying water during water outages to affected areas need to comply with norms and standards as set by the contract with Johannesburg Water.  She says this is to ensure that the public is supplied with potable water of an acceptable standard.

According to Du Plessis these standards include the following: 

• The quality of the water distributed should not deteriorate through the contractors handling. Cleanliness is required at all times.
• Random sampling of water in tankers is done by Johannesburg Water at accredited laboratories.
• Water tankers should be flushed and sterilised by the contractor at least once a month. A programme for the cleaning of tanks is required and needs to be submitted to the regional manager at the commencement of a supplier’s contract.
• Should it be found that the water transported is of an unacceptable quality, the specific water tanker will be decommissioned and penalties will be applicable until a suitable replacement is found.
• Any damages caused by the use of water that was contaminated during transit will be totally for the contractors’ attention and cost.

What should people do when using water from the trucks

Barnes says unfortunately, the usual community health advice in situations when people have to use water of suspect safety is to boil water used for drinking, cooking and actions such as brushing teeth for at least three minutes. 

“This implies that a large amount of extra fuel (wood, etc) or electricity will be needed. People living under conditions where water interruptions occur are already under pressure. Many cannot afford the extra burden or money to get extra fuel for increased heating of water. Thus it is imperative that communities already living under crisis situations should be able to trust that the emergency water supplied to them is safe,” she says. 

Du Plessis adds that the water supplied by water tankers should therefore be of an acceptable standard.

“However, if consumers are worried or do not trust the quality of the supplied water

of these water trucks, it is advised that they boil the water before using it,” she says. – Health-e News