Sakaja inspects Nairobi Dam works as county moves to avert flooding

Nairobi Governor Johnson Sakaja during an inspection of the ongoing spillway and embankment strengthening works at the Nairobi dam in Lang’ata on October 13, 2026./HANDOUT

Emergency works at Nairobi Dam are helping reduce flood risk in downstream estates as the county prepares for the anticipated El Niño rains, Nairobi Governor Johnson Sakaja said.

Sakaja said teams had constructed a spillway channel to direct excess water towards the Ngong River, easing pressure on the dam and helping protect residents, businesses and infrastructure in vulnerable areas.

The governor spoke on Tuesday, October 13, during an inspection of the ongoing spillway and embankment strengthening works at the dam in Lang’ata.

The interventions follow the dam’s overflow during the March 2026 rains, which raised concerns about the safety of communities downstream, including Lang’ata, Madaraka, South C and South B, as well as areas along Lang’ata and Mombasa roads.

“The dam, situated in an elevated area in Lang’ata, had posed a danger to people downstream, including residents in high-rise buildings and neighbourhoods such as Madaraka, South C, South B, as well as areas along Lang’ata and Mombasa roads,” Sakaja said.

Nairobi Governor Johnson Sakaja during an inspection of the ongoing spillway and embankment strengthening works at the Nairobi dam in Lang’ata on October 13, 2026./HANDOUT

The emergency works have included dredging, deepening sections of the watercourse, reclaiming riparian areas and removing walls in some South C estates to allow water to flow through designated channels.

However, Sakaja said the ongoing works were only an initial intervention, with a comprehensive rehabilitation of the entire dam planned after the El Niño rains.

“This is just an initial intervention. We have a plan underway to rehabilitate the entire dam, which will be undertaken after the El Niño rains,” he said.

Nairobi Governor Johnson Sakaja during an inspection of the ongoing spillway and embankment strengthening works at the Nairobi dam in Lang’ata on October 13, 2026./HANDOUT

The planned rehabilitation is expected to address longstanding concerns over the dam’s condition, water management and environmental degradation.

Built in 1955 as part of the Ngong River flood attenuation system, Nairobi Dam was designed to help regulate floodwaters and protect downstream areas, including Nairobi West, South C and the Industrial Area.

Over the years, pollution, sediment accumulation and maintenance challenges have raised concerns about its ability to manage rising water volumes during heavy rainfall.

The spillway works form part of the county’s wider El Niño preparedness programme, which includes clearing drainage systems, desilting rivers, rehabilitating waterways and removing waste obstructing stormwater channels.

The ongoing spillway and embankment strengthening works at the Nairobi dam in Lang’ata on October 13, 2026./HANDOUT

The county has also intensified clearance and rehabilitation works along the Nairobi, Mathare and Ngong rivers. Sakaja previously reported that the interventions had reached 80 per cent completion.

The ongoing spillway and embankment strengthening works at the Nairobi dam in Lang’ata on October 13, 2026./HANDOUT

The measures are intended to improve stormwater flow through the city’s drainage network and reduce flooding risks in residential and commercial areas.

Residents have been urged to avoid dumping waste in drainage channels, keep their surroundings clean and support efforts to protect waterways.