Drivers Warned of Delays as Key Nairobi Highway Faces Month-Long Partial Closure
Nairobi, 4 August 2026
Nairobi’s vital Mombasa Road will partially close for 36 days starting 10 August 2026, as engineers construct a critical flood-mitigation culvert to prevent seasonal transit paralysis.
Infrastructure Intervention for Flood Mitigation
On Monday, 3 August 2026, the Kenya National Highways Authority (KeNHA) announced a temporary partial closure of Mombasa Road (A8) at the Highway Educational Complex near Bellevue [1][3][4]. Scheduled to commence on Monday, 10 August 2026, and run until Monday, 14 September 2026, this 36-day project is designed to facilitate the construction of a critical box culvert [1][4]. The primary objective of this drainage structure is to mitigate severe stormwater flooding and erosion at a low-lying corridor that has historically been prone to flash floods that paralyse city transit during heavy rains [1][2].
Economic Significance and Expected Delays
Mombasa Road is a vital arterial route linking Nairobi’s central business district and industrial areas to the southern corridors, including Jomo Kenyatta International Airport (JKIA) and the coast [2][4]. Consequently, the partial closure is anticipated to cause moderate transit delays, with heavy trucks and buses likely experiencing longer travel times [2]. KeNHA Director General Eng. Luka Kimeli issued a public notice advising motorists to follow the proposed traffic management plan, use real-time traffic updates, and cooperate with traffic marshals and police officers on-site [2][4].
Traffic Management and Alternative Corridors
To minimise traffic disruption, both bound lanes will be closed interchangeably, allowing motorists to utilise the remaining two open lanes throughout the construction period [1][3]. For drivers travelling towards Mombasa or Mlolongo, KeNHA recommends utilising Likoni Road and Enterprise Road to rejoin the A8 highway near General Motors, or connecting to the Southern Bypass near Ole Sereni [1]. During peak hours, motorists commuting from Mlolongo or JKIA towards Nairobi city centre are advised to exit at the Southern Bypass Interchange and route through Lang’ata Road or Raila Odinga Road [1].
Alternative Routes for Light Vehicles
Light vehicles have the option of using internal estate roads within South C, specifically Popo Road, Kapiti Road, and Muhoho Avenue, though these residential pathways are expected to face heavy congestion [1]. The temporary closure will also likely increase traffic volumes across alternative bypasses and roads, including Lang’ata Road, the Southern Bypass, Enterprise Road, Likoni Road, and Lusaka Road [1]. Estates adjacent to the corridor, such as South C, Nairobi West, Madaraka, Imara Daima, and areas near Capital Centre, will also feel the impact of the diversions [1].
Broader Efforts in Road Infrastructure Resilience
This drainage project aligns with KeNHA’s broader efforts to improve road safety and durability, as proper water management reduces potholes and pavement erosion on high-speed corridors [2]. The authority recently executed similar infrastructure works on the Emali–Isineti (A5) Road near Simba Cement, which was partially closed from Friday, 24 July 2026, to Thursday, 13 August 2026, to install a drainage culvert across a natural channel [3][5]. During that period, traffic was diverted through a 100-metre temporary single-lane route [3][5]. Normal operations on Mombasa Road are scheduled to resume once the Bellevue culvert works are completed on 14 September 2026 [1][3].