A man looks on as members of the South African Police Service (SAPS) K9 search and rescue unit searches for a missing 23 year old man in KwaNdengezi, west of Durban, on April 20, 2022. - South Africa's government April 19, 2022 sought to reassure a worried public about efforts to help the east coast, where millions remained without water more than a week after deadly storms pounded the region. Some 10,000 troops were being deployed to assist, both with air support for search efforts and relief operations, but also with engineering, plumbing and electrical support to try to get basic services running. (GUILLEM SARTORIO/AFP via Getty Images)
Nearly three years ago, Durban’s climate action plan warned how storms and flooding would become more intense and strike more often.
Climate change is projected to alter rainfall patterns in Durban by intensifying rainfall variability. “While average annual rainfall is expected to increase overall, this increased rainfall will generally be experienced through more intense storm events, resulting in more intense and frequent flooding,” the 88-page document stated.
Two effects are expected — more intense and more frequent downpours. “For extreme rainfall events, the intensity can increase significantly … The occurrence of these downpours will increase.”
The plan, prepared by the eThekwini metropolitan municipality, described how existing one-in-10-year events will occur up to three times over a 10-year period. “The combination of these two effects gives a much higher flood risk. This also includes sudden flash floods, which are already occurring in Durban.”
‘Prepare for what’s coming’
The city’s east coast is grappling with the devastating toll of the torrential rainfall that dropped between 200mm and 400mm in days at its peak, triggering flooding and mudslides that left at least 448 people dead, displaced about 40 000 people and unleashed billions of rand in damages.
In 1987, “equally devastating” flooding killed 506 people in KwaZulu-Natal and caused widespread damage, said Alize Le Roux, a senior researcher at the African Futures and Innovation unit at the Institute for Security Studies.
“We saw this kind of flooding again on Christmas Day in 1995 in KwaZulu-Natal and again in April 2019 … South Africa has a short collective memory. We don’t have a proper disaster database that’s recording these events so we’re not learning from these previous disasters.”
KwaZulu-Natal is “used to” flooding, Le Roux said. “But most of the climate projections show that the province and specifically that area that has now received so much rain, will become wetter going into the future in terms of more extreme rainfall events — so larger amounts of rainfall in shorter periods of time. They have to prepare for what’s coming.”
By 2050, Durban’s rainfall projected to increase
According to the Green Book, an online climate risk profiling and adaptation tool developed by the Council for Scientific and Industrial Research (CSIR), if global greenhouse gas emissions continue to increase rapidly under a worst-case scenario, Durban’s average annual rainfall is projected to increase by about 120mm by 2050.
“That is something and it could be more,” said Willemien van Niekerk, the project leader of the Green Book. “It could range up to almost 200mm extra per year by 2050 … The problem is that it might come down all at once as we’ve seen now in this case. It’s not that it’s spread over the whole year, it becomes more extreme events … resulting in the type of flooding that we’ve seen now.”
The Green Book shows that extreme rainfall days range between 2.5 and 2.9 on average for Durban. “And that’s what we’ve seen now with this extreme rainfall event. What climate change projections tell us is that these events are becoming more frequent and when they happen, it’s also more extreme.”
All the country’s municipalities — although not to the same extent — “need to prepare” for these extremes in the future, Van Niekerk said. “That is why we have these future projections, that they know that they can expect these types of climatic changes but also hazards.
“If you look at the hazard modelling, it’s becoming more severe in the future and therefore you need to prepare, to adapt, and to mitigate the impact of these events on your population, on your economy and on your infrastructure because otherwise it’s just so devastating.”
‘Climate proofing’ infrastructure
Investment in climate-resilient infrastructure must take centre stage, said Le Roux. “Simple things like our floodlines need to be determined, people need to be made aware if they are living in a floodline. We need to protect open spaces, restore ecological infrastructure, do catchment rehabilitation, specifically upstream … We need to relook at our stormwater systems because they are not designed for these types of extreme rainfall events.
“Most of the infrastructure where they design bridges and roads, they look at historical rainfall patterns … but they look at the one-in-50-year and one-in-100-year flood and design for that. But the climate is shifting so these large amounts of rainfall in a much shorter period of time is not accommodating this.”
Still, she said, “you cannot accommodate for all the extreme events that will happen” and that’s why building resilience within communities is crucial. “In some cases we will need to relocate critical infrastructure if we can’t protect it. For vulnerable communities, if we cannot protect them and if they are directly in harm’s way, we need to give them alternative places to relocate, otherwise we’ll see the same thing happening over and over.” Adapting to climate change needs to be mainstreamed “in everything we do” in the planning, construction, maintenance and retrofitting stages.
Safe, affordable, well-located land
The government, too, is at fault for failing to implement flood control measures, Le Roux said. “And many of the communities that have been affected have been warned that they are in locations that are unsafe. They’re settling in the one-in-50-year, in some cases in the one-in-10-year floodline, or on unstable slopes. It’s impossible to relocate these communities quickly. Land use disputes are battlefields so it’s a complex problem.”
Cities and the government need to open up safe, well-located and affordable land for people to settle on. “You can guide informality in areas that we know are safe and not susceptible to climate hazards … Even in Tshwane, we’ve identified 30 000 households located in the indicative floodline.
“So, if you get the same amount of rainfall in Tshwane, it’s the same amount of devastation — not to an equal extent because the topography looks a little different … If communities are in unsafe ground, no amount of flood protection measures are going to save them.”
Deadly combination
Urbanisation, coupled with extreme events, collide with devastating effect, Van Niekerk said. “Where you combine people, infrastructure and the economy and you get a rainfall event like we saw last week then that results in a disaster. If a lot of that infrastructure, people and the economy are exposed to that climate hazard and people are vulnerable, living in places you shouldn’t live and in structures that cannot withstand an extreme rainfall event like this, then you see that much destruction and loss of life.”
To save lives, municipalities such as eThekwini must reconsider the effects of climate change and extreme events in determining their one-in-100 year, one-in-50-year and one-in-20-year floodlines. “You need to know where they are so that you can ensure people don’t settle there by visibly demarcating your floodlines and your coastal risk areas.
“Communities might settle in floodlines or on floodplains because they don’t actually know, but if you physically demarcate them with bollards or something that can’t be removed or damaged easily, then people know, ‘I take a risk if I go beyond this point and settle on a floodplain.’”
Van Niekerk, an urban planner, doesn’t know of any municipality that does this. “I understand that it is a lot of effort and it costs something as well and that local government doesn’t always have money. But if you want to save lives, it’s an important measure to take, especially in areas where people are prone to settle informally, to show them that this is really a dangerous area to settle on.”
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