The government has approved the dualling of the 23.5-kilometre Muthaiga–Kiambu–Ndumberi corridor (Kiambu Road) to cut congestion and improve mobility between Nairobi and Kiambu counties.
A Cabinet brief issued on Tuesday confirms the project will expand the current two-lane highway into a dual carriageway, incorporating bypasses, loops, and access roads to increase capacity and reduce travel times.
The upgrade will also add non-motorised transport (NMT) lanes and commuter facilities to enhance safety and accessibility for pedestrians and cyclists.
The project which will serve Muthaiga, Runda, Ridgeways, and Kiambu Town, has a corridor that suffers chronic peak-hour gridlock.
The initiative forms part of a wider programme to modernise the Nairobi metropolitan transport network, aligned with Kenya Vision 2030 and the UN Sustainable Development Goals for infrastructure and mobility.
Once complete, the road is expected to streamline movement between the capital and Kiambu, boost economic productivity, and improve the daily commute for thousands of users. It is one of the busiest links between Nairobi’s northern suburbs and the rapidly growing residential and commercial hubs of Kiambu County.
In July, the Kenya National Highways Authority (KeNHA) said the project would markedly improve traffic flow across the eastern Nairobi Metropolitan area, targeting key corridors including sections of Kiambu Road and the Thika Superhighway.
KeNHA noted the scheme will upgrade the existing two-lane single carriageway into a four-lane dual highway with service lanes on both sides, improving the level of service, safety, and accessibility through dedicated service roads and NMT facilities.
Works will be delivered under the Engineer-Procure-Construct (EPC) model, using the FIDIC Silver Book; an international standard that prioritises cost and time certainty by placing greater performance responsibility on the contractor. The plan also includes six pedestrian footbridges to improve safety for residents and commuters.
The project covers the main Muthaiga–Kiambu–Ndumberi stretch and adjoining spurs, including Ridgeways Road, Kiambu Road to Thika Road, and UN Avenue through Runda.