Massive water lost to Limpopo River
Pini Bothoko | Tuesday March 7, 2017 17:14
The assistant Minister of Land Management, Water and Sanitation Services, Itumeleng Moipisi enlightened Parliament yesterday responding to a question from the Member of Parliament for Mochudi West, Gilbert Mangole.
Mangole had wanted to know if Government is aware that a massive amount of water is currently lost to South Africa through Notwane, Metsimotlhabe and Thagale Rivers in Kgatleng District.
He also questioned if Government does not consider it prudent to construct a small to medium-sized dam in the same district, where the three rivers merge into one, to harness the resource before it reaches the international source.
When answering, Moipisi said his Ministry is aware that during heavy rainfalls in the Notwane catchment area, water drains into the Limpopo River system through Notwane, Metsimotlhabe and Thagale Rivers.
He said a pre-feasibility study of potential dam site and off-river storage on the lower-Notwane River was undertaken in March 2009 by the Ministry of Minerals, Energy and Water Resources, which engaged consultants who produced the final report in May 2010.
Moipisi said that the study indicated that the Thagale/Notwane confluence is not a potential dam site.
“The site was not a potential dam site because the confluence area is generally very flat, no visible features like rock outcrops to suggest potential for a dam or weir site and increased cultivation was observed in this area up to Mochudi village,” Moipisi explained.
He, however, said the study located three possible dam sites, two of which should be further investigated.
“The sites are the Lethekane Ridge dam site, Oodi weir site and Mochudi weir site,” Moipisi cited.
Moipisi stated that the Mochudi weir site basin is both wide and densely populated, which tends to be problematic when assessing flood lines, therefore the site was disqualified due to environmental and social issues.
He said the study would require detailed investigation in the hydrology, and more particularly the correlation of river flow of rainfall to determine the potential for annual water harvesting.
“The study will require the typology of dam materials, operating philosophy, which is dependent on where the water will be supplied and at what rate.”
He added: “It also required detailed investigations on consideration on water quality as it is located below the city waste water treatment facilities, modelling and optimisation of water resource parameters as well as to consider environmental impact and socio-economic issues”.
Moipisi said that it is anticipated that the detailed study would cost around P10 million based on similar studies undertaken recently.