The South African Municipal Workers Union (Samwu) on Wednesday said it was disappointed by the water and sanitation department's plan to cut off water supplies to defaulting municipalities.

General secretary Simon Mathe described the move as "an evil plan" which would leave millions of South Africans without access to water.

On Monday, Water and Sanitation Minister Nomvula Mokonyane said the looming water cuts were not a punishment but were meant to force defaulting municipalities to pay their debts.

The department issued notices to at least 30 municipalities informing them that water supplies would be cut off on December 8 should they fail to settle their arrears, which have been outstanding for more than 60 days.

Mokonyane said further explained that municipalities actually owe R3.8-billion, and water boards, the entities that implement department projects, owe R3.2-billion.

"It is very disappointing that Nomvula Mokonyane, the Minister of Water and Sanitation, as someone who has ambitions of being in the national leadership of ANC [African National Congress] could hatch such a plan without taking into consideration the ramifications particularly on the working class and the poor," Mathe said.

"We understand that the country is facing a water crisis, we are however of the view that this water crisis has been engineered particularly by the department of water and sanitation under the leadership of Mokonyane who has deliberately delayed the Lesotho Highlands Water Project allegedly so her cronies can benefit from some of the contracts."

Mathe said municipalities do not exist for profit-making but their constitutional mandate of the delivery of services.

"It would, therefore, be immoral, unethical and evil for anyone to even think of interrupting water supply as an attempt to force municipalities to pay their debts," Mathe said.

He said municipalities were "heavily underfunded" and yet were expected to deliver services.

"The minister should rather be advancing an idea of how municipalities can better be strengthened so to ensure that they continue with their constitutional mandate instead of leaving South Africans without water in their homes."