Nairobi Infrastructure Deficit Heightens El Niño Flood Risks for Informal Settlements

Nairobi's municipal disaster management authorities have warned that millions of residents in informal settlements face severe risks from upcoming El Niño weather patterns due to an unmaintained and capacity-constrained drainage network. Local officials stated that immediate interventions are focusing on clearing accumulated rubbish from existing channels to reduce localized flooding during heavy rains.

The current drainage system was constructed 30 years ago to serve a population of approximately 2.5 million people. According to Nairobi County disaster management chief Bramwell Simiyu, the city now handles around 7 million daytime residents and 5.5 million night-time residents without corresponding upgrades to basic civil infrastructure.

The strain on infrastructure is concentrated in low-income areas situated along river corridors, such as Kibera and Mathare. In these informal settlements, ongoing urban expansion has led to housing being constructed directly on river slopes and within metres of watercourses. During intense rainfall, flash floods submerge these structures, placing occupants in immediate danger.

Full rehabilitation of Nairobi's sewerage and drainage infrastructure requires an investment of $192 million, according to county estimates. Neither the national government nor the city council currently possesses the financial resources necessary to fund the project, leaving the long-term structural issues unaddressed.

A study conducted by the government-backed Nairobi River Basin Regeneration programme identified weak enforcement of planning regulations and unchecked development along riverbanks as major factors expanding flood zones. The programme recommended establishing protective buffer zones along waterways alongside the humane relocation of affected communities from high-risk areas.

Written by Freya Stensrud freya.stensrud@alpineweekly.com