Nairobi, Kenya’s capital, has been battered by relentless rains for six weeks, resulting in devastating floods and loss of life. More than 120 people have died, with at least 50 casualties from a deluge in an area about 60km (37 miles) from Nairobi. Though this is the wet season, the rainfall has been far heavier than usual, attributed to the El Niño weather phenomenon.
The excessive rainfall has caused rivers and sewers to overflow, turning roads into waterways and destroying homes. Flooding is not uncommon in Nairobi, but this year’s severity reveals deep-seated issues in the city’s urban development. Prof. Alfred Omenya, an expert in urban planning and the environment, explains that much of the city lies on the floodplain of the Nairobi River, with other rivers and streams also flowing through the capital. Although a robust drainage system could mitigate flooding, Nairobi’s rapid growth from 100,000 residents a century ago to 4.5 million today has outpaced infrastructure development.
A significant problem is that less than half of Nairobi’s residents are connected to a sewage system. In slum areas, open sewers are common and easily overflow when it rains heavily. Additionally, drains are often blocked by household rubbish, and urban development has encroached on open spaces, reducing the ground’s ability to absorb water. As more concrete covers the earth, water runoff overwhelms drains and rivers, turning roads into impromptu drainage channels.
Prof. Omenya attributes these problems to “clueless leadership that started from the colonial times.” Unplanned settlements have developed around rivers, disrupting their natural flow. Many slum areas, such as Mukuru and Mathare, are built on marginal land along river valleys, making them vulnerable to flooding. Tragically, a dozen bodies were retrieved from the Mathare River after heavy rains last week, with residents trapped on their roofs due to flooding.
Even upscale neighborhoods, typically unaffected by floods, have experienced significant water damage. Nairobi Governor Johnson Sakaja cited the encroachment on land surrounding rivers as a key reason for the flooding crisis. To address this, he has suspended approvals for new building developments and excavations, while President William Ruto announced plans to relocate people living in dangerous areas to safer land provided by the National Youth Service. The government is also working with the military and local authorities to support those affected by floods.
Kiambu County, neighboring Nairobi, has also been hit hard by floods and announced measures to mitigate the impact, including building inspections. However, past efforts to address irregular developments through demolition have had limited success. In 2018, major commercial centers like South End Mall and Ukay Mall were demolished to reclaim wetlands, but unplanned construction persists.
Prof. Omenya and other experts suggest that the original colonial masterplan, designed with the land’s topography in mind, was never fully implemented. Post-independence, other blueprints aimed at improving infrastructure have also failed to take hold. With climate change potentially intensifying rainfall, a comprehensive new plan is urgently needed to prevent future disasters.
Meanwhile, ordinary Nairobi residents are left to cope with the aftermath of the floods, cleaning up and hoping the rains will subside.
