Happenings at the Wonderfonteinspruit over the past week or so proved again that it is an unusual river linked to the area’s mining history.

Bird watchers suddenly reported that the water had almost stopped flowing about two weeks ago. The effect was visible near the bridge in Khutsong, where some people fish despite water pollution warnings, and at the bridge outside Welverdiend. Here, the river had dammed up to such an extent that it created an artificial wetland with many water birds like flamingoes.

At the same time, members of the Merafong Business Forum complained that they were not employed when contractors of Sibanye-Stillwater were working on the pipeline that forms part of the river. This work site was next to the gravel road to the Eye of the Wonderfonteinspruit. This eye no longer exists because the water is pumped into a pipe on top of the ground in the area. Sibanye-Stillwater’s EVP of Investor Relations and Corporate Affairs, Mr James Wellsted, shed more light on the recent happenings on the river.

“Work is currently being conducted around the one-metre pipeline, designed and installed to convey water from the Upper-Wonderfonteinspruit over the dolomitic area of certain gold mines in Westonaria. The Far West Rand Dolomitic Water Association, of which Sibanye-Stillwater is a member, owns the pipeline. It was built in 1977 because the area was dolomitic and had a complex surface-groundwater interaction (karst system). The dolomite is relatively soft, and the area is prone to sinkholes. The pipeline was necessary to limit surface water migration into these voids and reduce the probability of sinkhole formation,” says Wellsted.

“The pipeline is old and requires regular maintenance and remedial work to reduce the risk of periodic structural failures. Vandalism, theft by scrap metal collectors and illegal miners, and damage from sinkhole formation exacerbate the risk. While Sibanye-Stillwater routinely undertakes maintenance work and related interventions to address these challenges, a more intensive remedial programme started last year and should be completed in April 2024).

“The work entailed installing a new weir at the attenuation dam downstream of Donaldson Dam and a 2.5-kilometre bypass pipeline around the sinkhole area where the original pipeline is installed. This bypass line is a backup if the initial one is fouled or damaged by possible sinkhole formation. It is important to note that while this intensive work was underway, it did not impact the flow and water levels down the Lower-Wonderfonteinspruit.

“The installation of the new weir and bypass pipeline has been completed and commissioned. Outstanding work entails covering the new underground 2.5-kilometre bypass pipeline and will be completed by April 2024. However, this is subject to weather conditions, safety, and any unforeseen project deviations due to risks of spontaneous sinkhole development in the area and acts of vandalism. Routine maintenance will continue as normal and emergency repair work as and when it arises. Although the recent lower levels at the Lower-Wonderfonteinspruit were not related to the work on the one-metre pipeline, they may have been caused by a temporary diversion of water to enable the emergency construction of civil works required to reconfigure the canal integrity downstream to the confluence of the one-metre pipeline and the Driefontein canals, which have also undergone repairs. A new sinkhole that formed on 2 January and caused significant damage to the bypass canal required emergency construction work. Although attempts were made to divert water to the main canal, it could not handle all the water due to a restriction in the sub-pipe of the canal causing water to flow into sinkholes. While this emergency work was being carried out, water from the Driefontein canals was temporarily diverted to the Mooirivierloop where it subsequently went into the sinkholes in the Mooirivierloop, and there was no flow downstream. The emergency construction work at the canal close to Driefontein was completed on 22 January and water flow to the main canal was reinstated.

“The flow downstream is back to normal. It must be noted that the bypass canal damaged by the new sinkhole must still be remedied and will likely include rehabilitating the sinkhole first or installing a bypass system around the sinkhole. Wellsted also commented on the local contractors who wanted work.

“Sibanye Stillwater is committed to community upliftment and includes local SMMEs in most opportunities, but in some instances when urgent and critical action is required, in the interests of expediency and safety, service providers that are already contracted to the company and have the required skills may be appointed,” he says.