The Southern Bypass will be closed for 10 days from December 24 as the Kenya National Highways Authority (Kenha) undertakes repairs on three sections of the transit road.
The repairs, which will last until January 5 next year, will involve replacing expansion joints on three bridges along the road.
“We have selected this festive period when most of the traffic is expected to be reduced because most people may have travelled out of town,” said Denis Odek, the director in charge of Corridor A at Kenha.
Corridor A runs from Mombasa to Museum Hill before branching to Namanga, on the border of Tanzania.
The three bridges where the expansion joints will be replaced are Ole Sereni bridge, the Kibera overpass and at the Ngong Road interchange.
Jared Makori, Kenha's deputy director in charge of structures, explained that the expansion joints ensure smooth traffic flow on the bridge.
Expansion joints also allow for the expansion and contraction of the bridge due to environmental factors such as temperature, and enable the structure to respond appropriately to the impact of the traffic.
The contractor, Ebenezer Works Limited, will replace the existing expansion joints with new ones known as finger type expansion joints.
The finger type expansion joints can last up to 60 years, compared to the existing ones, which last for between 10 and 15 years, depending on exposure conditions and the type of traffic, explained Mr Makori.
“We appreciate that this is a busy road. We have on average 25,000 vehicles using the road daily. And a huge composition that is actually the trucks,” he said, noting that the popularity of the road with trucks is because it is a transit route.
Kenha reckons that if the damaged expansion joints are not replaced they will affect the overall performance of the bridge and in turn the design of the road.
“On average we design structures to last 120 years, but if the expansion joints are not working well, they might affect the overall durability of the bridge,” explained Makori.
“The reason we want to remove it is because it is not serving the purpose; it is not allowing the free movement of the bridge infrastructure the way it is supposed to be,” added Mr Makori.
The repair work on the three bridges is part of the performance-based maintenance of the Southern Bypass, which commenced in November 2022. The maintenance will cost the road agency a total of Sh716 million.
The Southern bypass is popular with trucks moving cargo from Mombasa to western Kenya and on to the neighbouring countries.
