Grahamstown's December water supply was potable and relatively safe according to tests done by Amatola Water and tabled at a special Council meeting on Thursday 6 February.
Grahamstown's December water supply was potable and relatively safe according to tests done by Amatola Water and tabled at a special Council meeting on Thursday 6 February.
But, Amatola Water's Chris Nair admits that current water quality still falls short of the prescribed standards, and local scientists point out that Amatola did not test for all potentially health-threatening substances.
"We still have a long way to go before we get it to a Water Board level," Nair said. "But, we are going in the right direction – the interventions we put in place late last year brought the quality up quite quickly."
Nair says the current water quality is within the level one limits of the South African National Standard (Sans), but because Amatola Water is "pushing the plants so hard now to fill up the reservoirs in anticipation of the arrival of Rhodes students, we are on the borderline".
He is confident that water quality will improve in the next month or so as water clarifiers are upgraded at both the Waainek and Kleynhans plants.
Three truckloads of sand have been delivered to both plants, and new nozzles will be delivered from France in two to three weeks time. Once they arrive, Amatola Water will start refurbishing one filter at a time.
"We will then be on the road to getting class one water. The sand will improve it overnight," Nair said.
Amatola Water senior technician, Lindelwa Ndonga, said that while most of the December water-quality readings were within acceptable and safe limits, there were high levels of turbidity in Grahamstown water, especially at the Extension 7 Clinic.
Turbidity, the cloudiness or haziness caused by individual particles inside water, measured 6.97 ntu in Extension 7. The recommended highest level is 1 ntu.
She said that elevated levels of turbidity may interfere with water treatment and disinfection and cause aesthetic problems. Because of the potential association of elevated particles with bacterial or microbiological contamination, the level of turbidity is used as a red flag for potential microbiological contamination or secondary water quality problems.
In addition, Ndonga said the high Heterotrophic Plate Count at the Beaufort Street Police Station could have been due to "aftergrowth in the distribution network".
Meanwhile, Dr Neil Griffin, research officer at the Institute for Water Research (IWR) pointed out that the Amatola Water tests did not test for heavy metal contamination, which could be harmful.
Four years ago, in February 2010 there were heated exchanges between a panel of Rhodes University professors and other experts who did not see eye to eye on claims at the time that the water was tainted by heavy metal toxins.
It was decided at a special Makana Council meeting yesterday that monthly test results of Grahamstown's water quality will published on the Makana Municipality website and in municipal buildings, including libraries and halls.
A spokesperson for the Kowie Catchment Campaign (KCC) said it welcomed this. "The publication of understandable interpretations of water quality results should at least be on the Makana website (http://www.makana.gov.za) and in Grocott's and on public notice boards, for example at public libraries."
How dangerous are turbidity, high chlorine in your water? Should you be worried about heavy metals?
TURBIDITY
"Turbidity could provide favourable conditions for the growth of bacteria. Once turbidity is high it tends to nullify the effect of the chlorine – it shields the chlorine from interacting with the bacteria and your filtration process might not be as effective and you may end up having undesirable bacteria in your water, like e. coli," Amatola Water senior technician, Lindelwa Ndonga, warned.
Dr Neil Griffin, research officer at the Institute for Water Research (IWR) agreed that the turbidity levels in several Grahamstown tests seemed high, but said that turbidity is an operational standard, not a health standard, and that no direct health threat could be inferred from the readings.
CHLORINE
A Kowie Catchment Campaign (KCC) spokesperson said that chlorine levels were extremely high at the Waainek Treatment Works, but this was expected since chlorine is used as disinfectant, and the operators need to dose to ensure a minimum concentration throughout the network to make sure that there is no biological growth through the distribution channels.
Chlorine levels are used as an indicator of the effectiveness of the disinfection process and accounted for why the readings for faecal and total coliforms were 0.
HEAVY METALS
Dr Neil Griffin, research officer at the Institute for Water Research (IWR) pointed out that the Amatola Water tests did not test for heavy metal contamination, which could be harmful.
Four years ago, in February 2010 there were heated exchanges between a panel of Rhodes University professors and other experts who did not see eye to eye on claims at the time that the water was tainted by heavy metal toxins. The debate followed a Dispatch report on allegedly dangerous levels of toxic heavy metals coming from a tap at a local ostrich export abattoir.
Unacceptable levels of aluminium, mercury, cadmium, arsenic and coliforms were allegedly detected regularly in the water by a South African Bureau of Standards accredited laboratory conducting tests for the Integrated Meat Processors of the Eastern Cape (Impec) Abattoir.
Makana water head, Dabula Njilo, admitted at the time that the aluminium sulphate levels were above the legal limit.
Also in 2010, Rhodes senior aquaculture/fisheries scientist Martin Davies accused the local authority and Rhodes of hiding years of water data he had compiled and given them in 2006. He said the data consistently showed high levels of aluminium and arsenic – which was worrying considering they had an accumulative effect on the body.
MORE TESTS NEEDED
A KCC spokesperson cautioned against using this single snapshot "as an absolute and definitive water quality result".
"One normally has the outcome of several measures on which to base a proper and complete risk assessment. Microbes can grow and concentrations can change quickly. Thus sampling results from one day cannot be generalised to water conditions days later. If any issues are suspected, it is essential to conduct more than one set of tests. Water toxicologists would recommend frequent monitoring – regular water quality tests on an ongoing basis," she said.
HIGH HETEROTROPHIC PLATE COUNT
Amatola Water senior technician Lindelwa Ndonga said the high Heterotrophic Plate Count at the Beaufort Street Police Station could have been due to "aftergrowth in the distribution network".
WATER QUALITY RESULTS FOR EXTENSION 7 CLINIC
Heterotrophic plate count @ 35 degrees Celsius (CFU/1 ml) 21
Total solids – dissolved (mg/l) 396
Turbidity @WTW (NTU): 6.97 Recommended level: less than 1
You can read the Department of Water Affairs water quality standards here:
http://www.dwaf.gov.za/dir_ws/DWQR/subscr/ViewComDoc.asp?Docid=244
