Umgeni Water, bulk water supplier for KwaZulu-Natal, has cautioned that the province is not yet safe from worsening drought conditions.

Umgeni Water spokesperson Shami Harichunder on Friday said they had taken a decision to intensify messages to communities that water shortages were still prevalent in KZN.

"The Mgeni system cannot meet the full water requirements of uMgungundlovu, Pietermaritzburg and Durban."

He said this meant that water restrictions of 15% have been implemented in Pietermaritzburg, uMgungundlovu and about 80% of Durban.

"At the same time, Umgeni Water has introduced water rationing through a cut of 15% in potable water production at its water treatment plants at Midmar, Pietermaritzburg and Durban. The amount of potable water Umgeni Water supplies to these municipalities has also been reduced by 15%."

Harichunder said water conservation initiatives would continue because available water would have to last "until the dry spell ends".

"Prospects for good rains at the end of winter did not look promising, as has been forecast by the South African Weather Service (SAWS) and Council for Scientific and Industrial Research (CSIR)."

He said projections by SAWS and CSIR are that rains, expected at well below average, are only likely to occur in September or in the first quarter of 2018.

Harichunder said Umgeni Water would try to ensure that available water lasts until dams fill up again.

"In order to effectively execute this, water restrictions and reduced consumption are imperative. We have had discussions about easing restrictions, but a decision was taken to stay with 15%.

"If we make changes at this stage and rains do not [materialise], it is possible that restrictions of 20% would have to be implemented in the new year. The sacrifices we make now could ease hardship in future."

Meanwhile, the City of Cape Town has advised residents to keep an emergency supply of two to five litres of water as it starts further pressure reduction which may interrupt supply to some high-lying areas.

On Wednesday, the City of Cape Town's council approved Level 4 water restrictions that started on Thursday.