Cape Town – While Cape Town residents are concerned about the earthy flavour of their tap water, Robertson residents feared "poo contamination" due to the taste and smell of their water.
On Tuesday, the City of Cape Town reassured residents who have detected an earthy flavour to their tap water that it remains safe to drink and is compliant with SANS241 standards.
The change in taste is due to the presence of geosmin in the raw water supply, said Xanthea Limberg, Mayoral Committee Member for Informal Settlements, Water and Waste Services; and Energy, on Tuesday.
As for Robertson's woes, the Langeberg Municipality said in a notice late on Monday afternoon: "An operational problem occurred at one of the reservoirs in Robertson that resulted in dirty water being released into the water distribution network that serves wards 1, 2 and 3 in Robertson.
"The problem has been rectified and the municipality is currently scouring the system to get rid of the dirty water. Residents are requested not to drink the water until the system is 100% clean.
"Langeberg Municipality sincerely apologises for this problem and will rectify the situation as soon as possible."
Lana Groenewald was one of many residents to cry foul on Langeberg Municipality's Facebook page: "HOURS after the problem occurred, you send an SMS to inform the community… Unacceptable, poor service and on the whole totally inconsiderate!!
"How many people drank the contaminated water before you bothered to inform the community that the water was unsafe for consumption??!!
"As per YOUR negligence: Will you be paying the medical bills for everyone suffering from upset stomachs? Will you be paying to replace / fix stained linen from the poor quality water today?"
Natasha Jaars posted that the "water stinks" and what it did to people's washing was another major gripe.
Amanda Frost posted: "Don't think I will ever trust the tap water in Robertson again😢."
Robertson has had a clean water supply problem in some areas over the past two days, the municipality's director of engineering services, Izak van der Westhuizen, told News24 on Tuesday: "It was from the sediment at the bottom of the reservoir.
"No sewage got into the water. The sewerage plant is about 4km away from the water purification plant."
Robertson residents had recoiled at the sight of the dark green water coming out of their taps on Monday. Van der Westhuizen said officials think someone may have opened an incorrect valve and let the sediment into the supply.
The pipes were cleaned out completely, but as a precaution the municipality conducted extra water quality tests before releasing supplies again on Monday.
Limberg said the high levels of geosmin in the raw water supply originates from Cape Town's main supply dam, the Theewaterskloof Dam.
"This is affecting the taste and smell of the water supplied from the Blackheath Water Treatment Plant to the central and south-eastern parts of Cape Town.
"The City is currently dosing powdered-activated carbon during the water treatment process to reduce the effect of the geosmin. However, it may take some time for the taste and smell of the water to normalise," Limberg said.
"It must be emphasised that geosmin poses no threat to human health. It is a naturally occurring organic compound and is responsible for the earthy taste of beetroot and the scent that occurs in the air when rain falls after a dry spell.
"The compound is sometimes present in water, particularly during periods of hot weather, and even minute concentrations of a few parts per trillion can be detected by the human palate."