Capetonians assured 'brownish tap water' is safe to drink

The city of Cape Town has moved to allay fears about “discoloured tap water” in some areas, saying tests confirmed that it did not pose a health risk.

Residents were, however, advised to continue boiling water if they noticed discolouration.

The city sent out an advisory late on Monday cautioning residents that “water in the distribution system is currently discoloured over a large part of the eastern, central and southern suburbs” due to a “process control fault” at its Faure water treatment plant. “As a safety precaution, residents are advised to boil the water before drinking, especially if it appears discoloured.”

Tests indicated that the water did not pose a health risk, the city said on Tuesday evening.

“While the problem has been contained, there may be pockets within the reticulation network that still experience some discolouration. Part of the potable water treatment process involves dosing the water with coagulating chemicals. An error in the dosage of this chemical led to the water retaining its brownish colour.”

The Faure plant receives water from Steenbras Upper Dam and the Palmiet River and it has a naturally occurring “tea” colour caused by fynbos and vegetation in the area.

The city said the coagulating chemicals in the treatment process cause natural particles in the water to “flock together” and be removed, purifying the water to the clear appearance residents are used to seeing running out of taps.

"As soon as we became aware of the problem, Faure service reservoir was isolated from supplying the system and supply was switched to Blackheath service reservoir," the city said.

The Faure treatment plant provides about a third of the water consumed by residents daily across the city.