Motorists planning to travel along the Nairobi-Nakuru highway (A8) on Friday, November 28, 2025, have been urged to reschedule their journeys or use designated alternative routes due to significant traffic disruptions expected for the official launch of the Rironi-Nakuru-Mau Summit road expansion project. In a public advisory issued on Wednesday, November 26, the Kenya National Highways Authority (KeNHA) announced that President William Ruto will preside over launch events at multiple locations along the corridor, leading to heavy congestion throughout the day.

The A8 highway is a critical artery of the Northern Corridor, which connects the Port of Mombasa to Nairobi and extends to landlocked nations including Uganda, Rwanda, and South Sudan. The road currently handles an estimated 20,000 vehicles daily, with this figure projected to grow annually, leading to severe traffic jams that cost the country millions of shillings daily in lost time. The presidential launch marks the official commencement of one of Kenya's most ambitious infrastructure undertakings, aimed at transforming the heavily trafficked route into a modern dual carriageway.

Official Alternative Routes

To manage the expected traffic snarl-up, KeNHA, through Acting Director General Luka Kimeli, has outlined several alternative routes for different travel plans. Motorists travelling from Nairobi towards Nakuru are advised to use either:

• The Ngong–Suswa–Narok–Mau Narok–Njoro–Nakuru route.
• The Nairobi–Thika–Magumu–Njabini–Ol Kalou–Nakuru route.

For those travelling from the wider Rift Valley region towards Nakuru or seeking to bypass the main highway, the following routes are recommended:

• Nakuru–Kampi ya Moto–Ravine–Makutano.
• Nakuru–Njoro–Molo–Mau Summit.

KeNHA has urged all road users to plan their journeys accordingly to avoid significant delays.

A Transformative Project for East Africa

The Rironi-Nakuru-Mau Summit highway expansion is a Public-Private Partnership (PPP) project valued at between KES 170 billion and KES 200 billion. The project will be executed by a consortium including China Road and Bridge Corporation (CRBC) and the National Social Security Fund (NSSF), who will design, finance, build, operate, and maintain the toll-highway for a 30-year concession period before transferring it to the state. The project also includes the strengthening of the 58-kilometre Rironi-Mahiu-Naivasha Road (A8 South).

The upgrade involves expanding the 175-kilometre stretch into a four-lane dual carriageway from Rironi to Naivasha, a six-lane highway from Naivasha to Nakuru, and a four-lane road to Mau Summit. It will also feature modern amenities such as service lanes, interchanges, wildlife and livestock crossing points, and bus bays to improve safety and efficiency. The highway is notorious for its traffic gridlocks, particularly during holidays, and contains accident-prone sections like the Salgaa stretch.

Economic Impact and Tolling Model

The expansion is a cornerstone of President Ruto's national infrastructure program and is expected to have a profound economic impact. By reducing travel times, lowering vehicle operating costs, and improving safety, the project will enhance the efficiency of cargo transport along the Northern Corridor, boosting trade and stimulating economic growth in towns along the route. According to a 2012 IBM study, traffic jams on this route cost Kenya KES 50 million daily.

Once completed, motorists using the expressway will pay a toll, with a proposed base rate of KES 8 per kilometre for passenger cars. This open tolling system means users will pay for the distance travelled. While the tolling model has faced some resistance, KeNHA has assured the public that alternative, non-tolled routes will remain available for those who do not wish to use the expressway. The project is scheduled for completion within two years of the commencement of construction, which is expected to begin before January 2026.