City acts against flood risks

Changes in the Klip River, coupled with development on the flood plain, have led to increased flooding in Soweto. Solutions are being sought.
RESIDENTS and road users along Klipspruit Valley Road in Soweto have been plagued by frequent flooding over the past few months; but they will not need to worry for much longer as City entities have put a disaster and emergency management plan in place.

People living along the Klip River floodplain are being movedMoving: Shacks along the Klip River flood plain“The flooding is not due to a burst water pipe or problems in the storm water system, as envisaged,” said the City spokesperson, Nthatisi Modingoane. “It is as a result of the high levels of silt within the [Klip River], which means there is not sufficient space for water in the river and run-off from rain to go.”

Other factors at play are that the river has changed over the years and is now also characterised by faster flowing water in certain areas; a higher water level, making it almost the same level as Klipspruit Valley Road; an overgrowth of reeds; and sewerage in the water caused by ageing infrastructure.

This means that the Rea Vaya Bus Rapid Transit system is not the cause of the problem, as may have been originally thought.

As this flooding places residents and road users at risk, short- and long-term interventions have been drawn up. The disaster and emergency management plan was designed by the Johannesburg Roads Agency (JRA), Joburg metropolitan police department and emergency management services as a short-term solution.

If the water rises above a certain level, the early warning system will kick in and the metro police will close the road and redirect commuters, while Rea Vaya will put into place its alternative route and station plan.

“When there is heavy rain or a threat of rain, the road is closed and needs to remain closed until the entire road is free of water,” Modingoane said. “This is done to protect road users.”

A number of short-term engineering initiatives have also been proposed, particularly to protect those living on Mtipa and Coka streets.

On Coka Street, the plan is to build a temporary embankment of sand bags and non-return valves to prevent water from endangering the houses. This is not possible on Mtipa Street, however, as an embankment would most likely lead to the damming of water, and so making the problem worse.

Relocation of residents has also been proposed for those living on the flood plain and where engineering measures prove impossible. A detailed site analysis has been done as part of the flood risk assessment, and the department of planning and urban management has identified safe land. It is working with the Johannesburg Property Company to rezone the area.

The housing department will also contribute by making serviced stands available for the houses most at risk, mostly on Mtipa Street.

“For the medium to long term, a plan is proceeding to identify the source of the silt and put in place preventative actions,” he said.

Further long-term solutions that have been suggested include: engaging with and, if need be, prosecuting mining companies for not managing their tailings; repairing the New Canada dam wall and raising it so that it can serve as an attenuation dam; limiting new developments in the Klipspruit Valley; and removing or widening the June 16th heritage bridge.

Stakeholders have all been brought on board to find solutions to the flood risks. “The flooding problems have been thoroughly looked into and the JRA has appointed hydrological engineers to assess the full catchment,” he added.