“In recent years, the country has had to confront the effects of climate change. We have had devastating wildfires in the Western Cape, destructive floods in KwaZulu-Natal, unbearable heat waves in the Northern Cape, persistent drought in the Eastern Cape, and intense storms in Gauteng,” said President Cyril Ramaphosa in his State of the Nation address in February.
The April 2022 floods that Durban experienced were the most catastrophic natural disaster recorded in KZN. They broke records in terms of lives lost, homes and infrastructure damaged or destroyed and economic impact — all metrics that we use to assess flood severity. Furthermore, a study undertaken by the University of the Witwatersrand and the University of Brighton confirmed that the incidence of flooding in the province has doubled in the last century — on a trajectory that is likely to continue.
The lead author of the study, Professor Stefan Grab, concluded: “We need to prepare for bigger rainfall events in our cities, and that doesn’t just apply to Durban, it applies to all South African cities and towns. We must get our infrastructure, especially drainage systems, in order. It is urgent that we better prepare ourselves for the heavy rainfall and flood events that are guaranteed to come in times ahead.”
The South African government is acutely aware of this imperative. In last year’s mid-term budget speech, Minister of Finance Enoch Godongwana said: “To cater for the growing pressures imposed by climate change on infrastructure, especially at the local level, we have created a resource pool to specifically respond to future disasters. In this regard, R372 million has been added to the municipal disaster response grant, while R1.2 billion has been added to the municipal disaster recovery grant.”
1.Of course, budget allocation is only one part of any comprehensive solution. Our infrastructure designs need to be future proofed considering the uncertainty of what lies ahead. This requires risk assessment methodologies that assess hazard, vulnerability and exposure. This should consider the likelihood and potential impacts of natural disasters, and how these hazards might affect people, assets, infrastructure and resources. A large storm in a remote area, where the population density is low for example, would have a significantly different vulnerability and exposure risk compared to a similar storm upstream of a heavily populated area with communities living along riverbanks.
2. The intense floods we are likely to see in the future will affect how we store water. Building dams and raising dam walls typically has significant negative environmental and social impacts, necessitating the development or consideration of novel alternatives instead. There are, for example, innovations focused on storing desalinated sea water within groundwater systems, a promising though still fairly niche approach. Stormwater planning would also need to be refocused. In the past, designs typically centred on getting water off site as quickly and efficiently as possible, often without enough attention being paid to where the water was ending up. Worsening storms will only increase the impact of this run-off. Alternative approaches will again be required, such as managing more run-off into the ground by limiting the extent of paved areas.
3.Grey infrastructure such as dams, reservoirs, drains and pipelines are certainly necessary in water management, but we should also be including green, nature-based solutions in our approach. Green solutions would include permeable pavements, urban forests, wetland restoration, and the planting of trees. Green infrastructure helps to prevent flooding by slowing down and absorbing run-off water. By acting as sponges, these interventions help to mitigate the risk and impact of floods. Resilience necessarily requires integrated or hybrid solutions, including green ones.
4. Successful infrastructure solutions require stakeholder engagement. We have to understand the individual circumstances and needs of the people living in a specific area, bearing in mind that what works for one community might not work for another.
In South Africa, the level of detail and success of our engagement with interested and affected parties is variable, and often depends on who is responsible for implementing the project. It’s important that we don’t ignore these critical voices, however. They know better than anyone how environmental hazards are affecting their homes, assets and livelihoods, and importantly, how they’re changing over time.
5. We should use technology to our advantage. Identification and mitigation of flood and droughts are increasingly being undertaken using modelling software and through improved information management. This typically makes the application of integrated solutions more effective. Software exists that can assess both the physical and the socio-economic impacts of flooding. It also assesses flood damage and how effective relief measures have been after the fact, enabling assessments of infrastructure loss and damage, the prevalence of water- borne diseases, the scale of the environmental degradation and which interventions are working. The lessons learnt from the KZN floods, and similar natural disasters, are only valuable if we act on them expeditiously. The design, implementation and maintenance of climate-resilient infrastructure is an absolute imperative, and needs to consider risk in a holistic manner, using the available software and adequately accounting for all stakeholders, including the environment and vulnerable communities.
Karen King is the Climate Resilience Director for Royal HaskoningDHV. Royal HaskoningDHV is an independent, international engineering and project management consultancy with 140 years of experience and 6 000 colleagues across the globe. In 2022, Royal HaskoningDHV celebrated 100 years in South Africa.
Saturday Star
Karen King