Roads and bridges in and around South Africa's largest city are in serious danger of collapsing, a leading newspaper reported this week.
Illegal miners trying to access remnants left in long-abandoned former gold mines are the cause of potential infrastructure collapses in Johannesburg, The Citizen newspaper reported
The illegal underground miners, known as zama zamas, are causing damage to hghways and other roads around Gauteng province that are in imminent danger of collapse, the newspaper said.
The Witwatersrand reef system beneath Johannesburg and neighbouring towns including Benoni, Brakpan and Springs is a sedimentary gold deposit formed millions of years ago by rivers and lakes.
Over the decades, legitimate mining carved out vast underground networks supported by rock pillars deliberately left intact to stabilise the ground.
But when those mines were abandoned, much of the gold remained. For zama zamas, deposits left behind are their target.
To add to the instability, dolomite rock beneath much of Johannesburg and Ekurhuleni (formerly the East Rand) is inherently unstable.
The newspaper says Johannesburg is literally built on a hollow honeycomb. Research by the University of Johannesburg found flooded mine voids increase hydrostatic pressure on dolomitic rock.
A study by the University of Pretoria documented over 3,000 cases of subsidence and sinkholes across Gauteng, showing a clear link between disturbed dolomitic land and ground collapse.
Places like Springs and Brakpan are seeing bridges slowly erode and roads collapsing.
Security operative Marius van der Merwe told the paper: “Roads are literally falling away. The unused part of Eloff Street extension in central Johannesburg has collapsed twice because there’s nothing holding it up any more.
“It’s not even a sinkhole in the traditional sense; it’s a tunnel right beneath the road surface that’s been hollowed out. And it’s happening in multiple places at the same time.”
The Citizen said that inside the zama zama tunnels there is evidence of mining equipment, the bare basics, old filthy shoes and overalls, half-eaten meals.
Some zama zamas sleep underground every now and then, others stay for months.
The illegal miners risk their lives by primarily repurposing old and unused mine shafts and tunnels by blasting away support structures left behind by legitimate miners, which held up the roofs of the mines.
They also collect surface rocks and mine whatever else they can find that contains or may contain a smidgen of gold.
This happens at Putfontein, outside Benoni, on Snake Road between Benoni and Brakpan, and a host of other sites.
Crushed rocks are washed using any available water source and the runoff, often containing poisonous chemicals like mercury and cyanide, flows back into the groundwater system, eventually into rivers and dams.
In Putfontein, an entire community has spring up catering to zama zamas.
In Putfontein, an entire community has spring up catering to zama zamas.
There is often violence between rival groups of miners. The Benoni City Times last month reported shooting incidents between different gangs. There have been multiple deaths across different mine sites.
Image: Sunday World
