The Nairobi Rivers Commission (NRC) has finalised the construction of the emergency spillway at Nairobi Dam, with water now flowing through the structure as the nation prepare for anticipated El Niño rains.
In a statement dated Monday, October 19, NRC Chief Executive Officer Brigadier (Rtd) Joseph Muracia confirmed that the emergency spillway was open, urging the public remain in preparation mode.
“The Nairobi Rivers Commission (NRC), in collaboration with relevant government agencies and the Nairobi City County Government, wishes to inform the public that the emergency spillway at Nairobi Dam is now open, and water is flowing through the spillway as part of ongoing preparations for the anticipated El Niño rains and the wider Nairobi Dam regeneration programme,” NRC stated.
The spillway construction and flood mitigation repairs officially began on October 13, in a multi-agency effort involving the NRC, Nairobi City County Government and other relevant government agencies.
Nairobi Dam Spillway under construction on October 13.
Photo
Sakaja Johnsohn
The project aims to improve the dam’s ability to handle increased water volumes during heavy rainfall while preparing the facility for comprehensive restoration under the wider Nairobi Dam regeneration programme.
It is also designed to divert excess water and help regulate reservoir levels, reducing the risk of water overtopping the dam during periods of heavy rainfall.
By providing a controlled route for excess water, the structure can also help protect the dam’s embankment from erosion and reduce the danger of structural damage caused by uncontrolled water flow.
The intervention is expected to support flood mitigation efforts along the Ngong River basin, although downstream water levels and flow conditions may change depending on rainfall and other environmental factors.
Residents living below Nairobi Dam, including those around Nyayo Highrise, Dam Estate, parts of Kibera, Nairobi West and Madaraka, have been urged to remain vigilant as water flows through the spillway.
The affected communities have been advised to keep away from flowing water and river channels, exercise caution and follow safety instructions issued by relevant authorities as the rainy season approaches.
The spillway is particularly important for neighbourhoods downstream because managing excess water can help reduce flood risks, although NRC indicated residents should not assume that the intervention eliminates the danger entirely.
Further downstream, areas around Strathmore University, T-Mall, South C, South B, the Industrial Area and parts of Mukuru could also face flooding risks depending on river conditions and rainfall intensity.
The latest intervention follows evacuation warnings issued by the NRC and other state agencies during the March long rains after the Water Resources Authority (WRA) raised concerns about rising water levels threatening the dam’s embankment.
Residents in Kibera, Nyayo Highrise, Dam Estate, Lang’ata, Nairobi West and Madaraka were given 14 days to relocate to higher ground ahead of planned action targeting structures along riparian land and river channels.
Kenya is experiencing the October-to-December rainy season, with the Kenya Meteorological Service Authority forecasting an over 90 per cent chance of strong El Niño conditions extending into early 2027.
November is expected to bring the heaviest rainfall, with storms potentially exceeding 50mm in 24 hours, while Kisumu has reported property damage and Nyeri has recorded 147.8mm in the past week.
An undated image of Nairobi Dam.
Photo
WRA