City not ready for ‘climate-change rain’

SOUTH Africa’s cities are illequipped to handle the barrage of high-intensity rainfall that climate change has brought, say water experts.

“We are starting to see a new pattern in rainfall, and urban areas can’t contain that much water because there’s nowhere for it to be absorbed,” said Water Research Commission CEO Dhesigen Naidoo.

“But we can plan for this high volume of rain. We need to change our storm-water drains because they are designed for a different type of rainfall and so are our roads. If this pattern of rain continues, we will see sinkholes and potholes emerging.”

Insurance claims amounting to more than R11-million have been lodged since the flash floods that damaged homes and cars and claimed six lives in Johannesburg and Ekurhuleni this week.

The South African Weather Service said on Friday that the flooding in Ekurhuleni was a “one in 200-year event”, with 79.4mm measured in one hour.

Climate change had brought with it “high-intensity rain which falls over a short period of time”, said Naidoo.

“Flash floods are almost inevitable during a drought, because the soil is too dry and cannot absorb such a high volume of water that quickly.”

Naidoo, who has been studying South Africa’s changing rainfall pattern over the past five years, said it was not “all doomsday”.

He said South Africa could even benefit if underground dams were built to collect and store water from the highintensity rainfall.

Johannesburg Roads Agency MD Sean Phillips called the flash flood an “act of God” that was beyond the capacity of the city’s storm-water systems.

“Major underground drainage systems including crossings through residential properties are designed for storms [of this magnitude] statistically happening once every 25 years.”

City of Johannesburg spokesman Virgil James said the cost of damage to infrastructure was still being determined. Gauteng premier David Makhura intends to declare some areas disaster zones.

Aven Kistan, head of insurance broker Aon’s client services, said its call centre had been inundated with calls since Wednesday afternoon.

A third “were related to motor vehicles while 70% were for household contents and building damage”, said Kistan.

He said clients had reported water damage to their cars, furniture, boundary walls, wood floors, clothes and even food.

The South African Weather Service’s Wayne Venter said more rainfall was predicted for Gauteng next week.