As taps, toilets run dry, what about drilling?

ALTHOUGH South Africa has a large amount of groundwater Joburg sits on hard-rock aquifers and does not have much access to this precious resource at a time when the water supply is limited.

Professor in hydrogeology at the Wits School of Geosciences Tamiru Abiye told The Star: “The total amount of groundwater in South Africa is 17 trillion metric cubes.”

He added, however, that this water was distributed in different areas, depending on the types of rock.

“Rocks, such as dolomite… contain a huge amount of water. In the western Krugersdorp area and around Delmas and Mpumalanga, we have a huge amount of groundwater. “

John Tonkin, a former president of the Borehole Water Association of Southern Africa (BWA) said:“In the Joburg context, we are sitting on mostly hard-rock aquifers that contain limited amounts of water hence the fact that virtually all our potable water comes to us from Rand Water via Joburg Water,” he said.

“To answer the question, is there enough water in the ground water reserve to sustain Joburg, the short answer is an emphatic no, not even for a year,” he said.

According to Tonkin, even if there were enough groundwater to supply the area during the drought, there was not enough infrastructure to exploit it.

“There is also a small detail of legislation that, at one stage, specifically prohibited the pumping of water across a boundary line so, to be compliant, every house would have to drill their own borehole.”

He indicated that, worryingly, some of the larger boreholes in the south which can yield 200 000 litres an hour were situated in areas where acid mine water was at its worst.

Abiye said people using boreholes within a 10km radius of any mine should be cautious about the water quality.

Tonkin said: “Some of our major concerns, in addition to acid mine water, are leaking sewers and unscrupulous people using boreholes for the disposal of engine oil, paint and other toxic liquids.”

Roy Shearer, the head of BWA’s pump installers division, said: “At times of drought, people return to groundwater but the majority is used by farmers for irrigation and mostly these waters are not monitored and the water storage is abused. SABS has standards in place but nobody adheres to these standards due to lack of policing.”

Tonkin added: “If groundwater is going to be used for domestic consumption, it must be tested at least biannually in areas with a low population density and annually in an urban environment.”