Gaborone Dam to dry up by September

Maranyane Ngwanaamotho | Tuesday April 29, 2014 12:25

Gaborone Dam as it appears on the latest water Utilities' update. The Dam was built in 1963, with the wall increased in 1984. It reached its lowest level of 11 percent last year PIC: WUC

WUC water resource manager, Joel Selemogwe said in Kasane last Friday that the dam is currently 14.7 percent full and they are currently pumping out 54 million litres per day from it.

In an address to the Hospitality and Tourism Association of Botswana (HATAB) annual conference, he said the 141 million cubic metre dam will run dry by September at current usage levels. The WUC is fighting to revive boreholes in Kgatleng and Ramotswa to plug the shortfall.

The greater Gaborone region, with a population of more than 500,000 people, uses up to 145 million litres of water a day.

It gets supplies from Gaborone Dam, the North-South Water Carrier, Molatedi, Bokaa and Nnywane dams.

WUC hopes to revive the Ramotswa boreholes by July and have Masama fully operational by September, which would both add an additional 38 million litres per day.

The corporation’s latest calculations indicate that once Gaborone Dam dries up in September and should the North South Water Carrier (NSWC) fail, the greater Gaborone area would experience a daily shortfall of 50.4 million litres.

The NSWC is experiencing frequent faults necessitating the replacement of a problematic 26-kilometre stretch near Palapye with steel pipes. Each burst costs consumers in greater Gaborone up to 20 million litres. Selemogwe said that for the third year in a row, southern dams have been receiving very low inflows.

“Declaration of drought in 2012 triggered the imposition of Level 2 restrictions in a bid to reduce the demand by 30 percent,” he said.

“Last year the restrictions were revamped in September by banning the use of potable water for activities such as construction, car washes and fountains.”

Selemogwe said unfavourable climatic conditions had been sighted as one of the key contributing factors to the water crisis. “It has been shown that there is a northeast-southwest gradation of mean annual rainfall,” he said.

“Sometimes 70 percent to 90 percent of the annual total rainfall may occur in only one month. Temperatures range from below zero in the south in winter and can be greater than 40 degrees in summer.”