Failure by authorities to properly treat drinking water supplied to residents of Delmas may have triggered the recent mass outbreak of diarrhoea in the Mpumalanga town.
Tests by the Department of Water Affairs and Forestry have shown ”insufficient levels” of chlorine were added to the water supply between September 11 and October 14, members of Parliament’s water affairs portfolio committee heard on Wednesday.
This resulted in a ”pulse” of contaminated water, with not enough chlorine in it to kill harmful organisms, being piped to residents, the department’s water-quality unit head, Leonardo Manus, told MPs.
”There was a period when [chlorine] levels were fluctuating … and unacceptable,” he said.
Water affairs had informed the municipality by letter of the situation at the time.
The latest outbreak of diarrhoea in the Delmas area, the second since its municipality assumed responsibility for water services in 2003, has affected over 1 000 people.
Water to the town, which consumes 160 mega-litres a day, comes from 10 boreholes and a Rand Water pipeline.
Manus said although too-low chlorine dosing was probably the ”trigger” for the recent outbreak, it was not a sufficient explanation for the problem persisting.
”Something else must be causing it,” he said.
The problem might be the result of mixing chlorine-treated water from the boreholes with that from the Rand Water pipeline, which was treated with a different chemical — ammonia chloramine.
”When you mix the two … you create new chlorine demand,” Manus said, implying chlorine levels could again be too low.
However, before any official conclusion could be reached, the records would need to be studied ”to determine what role this played in the outbreak”.
Manus noted that the three major outbreaks of diarrhoea in the town — in 1993, 2005 and 2007 — appeared to follow the onset of heavy rains in the region.
After the 2005 outbreak, it was recommended the town be connected to Rand Water via a new pipeline.
Manus said this had not yet been done due to a lack of funds, although he expected the project to be completed next year.
South African Municipal Workers’ Union national research officer Jeff Rudin — who was granted permission to address the committee meeting by chairperson Connie September — questioned the government’s priorities when it came to supplying safe drinking water.
The reason for the new pipeline not being built was a R78-million funding shortfall, yet the country had allocated R20-billion to build Soccer World Cup stadiums, he said.
The problems with drinking water in South Africa were not confined to one town.
”We’re sitting on hundreds of Delmases,” Rudin warned, noting research showed it was becoming unsafe to drink water in many parts of the country.
African National Congress MP Kay Moonsamy said the situation was grave.
The committee received constant assurances from department officials and experts that South Africa’s drinking water was fine, and fit to drink.
”This is a very grave problem. It is our … duty to take the matter up with the Minister [of Water Affairs and Forestry, Lindiwe Hendricks],” he said.
Manus told members that tests on the boreholes around Delmas — which is located atop a band of dolomitic rock — had revealed heavy faecal pollution in the water from some of the wells.
He said residents of informal settlements around the town used ”bucket system” sanitation. Although he did not put a figure on the number of people in these settlements, he said 1 000 more houses were needed for informal settlement residents.
This would suggest thousands of Delmas residents are still using either the bucket system or the local countryside as a toilet.
Manus also told MPs that chemical testing on water from one of the town’s boreholes had revealed high mercury levels, although it was considered safe to drink after being ”mixed and diluted” with water from other sources. — Sapa