The concrete barriers are aimed to stop nearby residents from crossing the highway.
“Work in most sections of the bypass is completed with the contractor just winding up,” KeNHA said in a press statement.
The contractor is also undertaking some landscaping to beautify the road before its formal opening – although the highway is already in use.
The Nairobi Southern Bypass project involved construction of a 28.6km dual carriageway with 12km slip roads and an extra 8.5km service roads.
Infrastructure Principal Secretary John Mosonik earlier said the completion of the road would ease traffic, reduce the effects of vehicle emissions and enhance socio-economic development in Nairobi.
“The development of urban roads, especially in Nairobi is crucial in ensuring there is minimal congestion for vehicular traffic. There is also need to provide pedestrians and non-motorised traffic with adequate and safe facilities in the city,” said Mr Mosonik.
The 17.1 billion project is 85 per cent funded by China’s EXIM Bank with the Kenyan government catering for the remaining 15 per cent.
Motorists will enter the bypass from the Nairobi-Mombasa highway near Park Side Towers and run on the edge of the Nairobi National Park, Langata South Estate, Ngong Road, Dagoretti, Gitara and Thogoto in Kiambu County where it will then join the Nairobi-Nakuru highway.
The road is meant to reduce congestion in Nairobi by providing an alternative route for motorists going to western Kenya and other destinations.
The Nairobi Southern Bypass, which was officially launched by President Mwai Kibaki early 2012, has seen its share of problems.
In June 2012, the project met with fierce opposition from Friends of the Nairobi National Park (FoNNP), who said construction of the road through the national park would put other national parks at risk of development.
The lobby group successfully petitioned the National Environmental Tribunal to stop the government from commencing construction works on the areas in dispute. The issue was later resolved.
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