A total of 22 water supply systems around the country have earned "Blue Drop" status.
According to a Department of Water Affairs report released on Tuesday, more than third (eight) are in Western Cape, while in Limpopo - which has been beset with water quality problems in recent months - not one of the six water service authorities assessed qualified for the award.
Of South Africa's major cities, only Port Elizabeth and East London (Nelson Mandela and Buffalo City) failed to obtain Blue Drop status.
Water boards serving Gauteng came in for particular praise.
"The Gauteng province has performed exceptionally well since the vast majority of the population is served from water supply systems that have been certified with the prestigious Blue Drop status.
"The performance of the water boards in the area contributed to this favourable situation."
The report states Western Cape fared "rather well", but warns three low-scoring water service authorities in the province will be placed under close surveillance until they improve. - Sapa
lSee box for a full list