Why African cities will linger in the crosshairs of floods

Already, more than 238 people have died with over 47,000 households displaced from their homes across the country.

As the soils become saturated with water, several buildings have shown signs of instability, with one flat in Uthiru collapsing on Tuesday.

Sadly, with the rains predicted to continue for the rest of this month and probably the next, the country is yet to see the end of such horrid scenes.

While many seem baffled by the widespread flooding across the region, experts say high population density and poor disaster mitigation systems many African cities will continue to suffer from increased climate vulnerability.

At the core of the flooding, notes research from ScienceDirect, are human factors that could have been avoided, or at least mitigation measures put in place to lessen human suffering.

“Human factors such as poor urban planning and development of the city, a poor drainage system, poor solid waste management and non-enforcement of laws, rules and regulations guiding building codes in the city were highlighted,” the research says.

Studies conducted over the last six years show that Africa’s low-lying cities are likely to be more prone to flooding, erosion, and storm surges than others.

Such cities include Kampala in Uganda; Lagos, Nigeria; Luanda, Angola; Addis Ababa, Ethiopia and Dar es Salaam, Tanzania. Nairobi is not off the hook since it lies on what was once a swamp where local herdsmen used to water their livestock.

With Africa’s population rising, more and more people are constructing homes on riparian reserves where water hardly drains even after a brief downpour.

The Intergovernmental Panel on Climate Change (IPCC) says in a new report the urban poor who live near waterways or sewer lines will continue to be in harm's way during periods of heavy downpour.

“Many low-income residents live in informal settlements alongside coasts or rivers, which greatly heightens exposure and vulnerability to climate-driven hazards. This risk of flooding is greater for coastal settlements due to sea level rise and storm surges from tropical cyclones,” says the IPCC Working Group Assessment report on cities, settlements and key infrastructure.

The report adds: “People who already have fewer resources and constrained opportunities face higher levels of risk because of their vulnerability.”

In addition, key projects such as roads and residential buildings continue to reduce the surface area meant for water runoff, increasing the likelihood of high volumes of stagnant water or floods.

This week, the government has had to close several roads, including the Narok-Mai Mahiu Road due to flooding.

Runda estate

Interestingly, UN Avenue, the main thoroughfare leading to the United Nations Environment Programme (UNEP) headquarters was closed near the upmarket Runda estate as a result of flooding.

“The density of roads and buildings in urban areas increases the area of impermeable surfaces, which interact with more frequent heavy precipitation events to increase the risk of urban flooding,” says the IPCC report.

While the International Monetary Fund (IMF) estimates that eight of the top 10 fastest-growing economies between 2018 and 2023 are in Africa, the cost of mitigating the ravages of climate change-induced hazards such as flooding will be enormous.

And as the “full effects of urbanisation and climate change unfold, companies investing in these markets could face a set of costly risks.”

Landry Ninteretse, regional director at 350Africa.org says between now and 2050, the populations of 28 African countries are projected to more than double, constituting the most rapidly urbanising region on the planet, with the percentage of people living in African cities currently rising by 16 per cent and reaching a level of 56 per cent by 2050.

These conditions will further complicate efforts by governments to mitigate climate change impacts such as rising water levels, property destruction, coastal erosion, flooding, and damage to infrastructures.

Already, climate experts warn that these urban areas already with poor urban planning, lack adequate infrastructure, water, and health facilities to accommodate urban migrants who are then exposed to extreme poverty rates.

The World Bank predicts that there will be 86 million internal climate migrants in sub-Saharan Africa by 2050.

“While it's hard to estimate how many people leave their villages due to climate change, the truth is that most of them migrate because of economic or socio-political factors that are affected by climate change. Climate change impacts such as poor farm production, difficult access to water sources, or persistent conflicts between farmers and pastoralist communities,” says Mr Ninteretse.

The current flooding has also destroyed thousands of acres of agricultural land, especially in the Rift Valley, often termed as Kenya’s food basket. This means that soon, the country will grapple with food insecurity.

In a past interview with Quartz, philanthropist Bill Gates said food aid to Africa has “accelerated in response to war, economic turmoil, and climate change,” while agricultural investments in poor countries have either waned or stagnated.

“There’s no doubt food aid has saved lots of lives. But it’s very tricky. Sometimes you get too little, sometimes you get too much and you cause the price of food to drop below local farmers’ cost of production and you can mess up the normal agricultural markets,” said Mr Gates.

Urban population

He also highlighted the nexus between the high urban population in Africa and climate change and the attendant population trying to feed the rising numbers.

“Given the cost of labour and the availability of land, Africa should be a net food exporter. But because of low productivity, it’s a net food importer," said Gates.

"The urgency of the innovation pipeline comes both from the need to get African productivity up and also from the fact that the closer you are to the equator; the more damaging climate change is for agriculture. And Africa is the last place in the world where you have significant population growth."

While the IPCC report recommends several mitigating measures against floods, including “installing flood proofing measures within and outside properties and improving the capacity of urban drainage along roads,” Nairobi’s century-old drainage system has seen little upgrade despite serving over four million people.