The pollution problem at the Hartbeespoort Dam was "historic in nature", the water affairs ministry said on Monday, in response to legal threats against the department.
"It must be borne in mind that the challenges that plague the dam are historic in nature and have been in the making for more than 80 years," acting director general Nobu Ngele said in a statement.
She was responding the media reports that an environmental lobby group was planning to bring criminal charges against Water and Environmental Affairs Minister Buyelwa Sonjica for the pollution contaminating the dam.
Ngele said a programme to eradicate the pollution was showing progress
"The fish composition in the dam has already improved since the implementation of this programme."
The Harties Metsi Ame programme was established in 2006 to deal with water pollution and to address the issue of illegal waste being discharged into the Hartbeespoort Dam.
"The first and short-term phase focuses on removing unwanted, exotic, sediment-feeding carp and barbel fish, establishing shoreline and wetland conditions in the dam and the introduction of biological and mechanical harvesting of algae and hyacinths" she said.
The second phase of the programme will focus on catchment impacts, improving storm water management; as well as protecting and remedying the problems in wetlands and in-stream river habitats. - Sapa