According to the Kenya National Highways Authority (KeNHA), the single-lane highway would witness traffic snarl-ups that lasted for hours on end.
However, the situation has turned worse with long stretches of the road under construction since 2015, and yet to be tarmacked.
According to the Environmental and Social Impact Assessment (ESIA) carried out by KeNHA, vehicle speed averages between 10-30km/hr across the road corridor.
During peak hours, it takes an average of 3-6hrs to traverse a distance of 16km from Miritini into the city centre.
To cap it off, the pollution in form of dust being kicked up by the thousands of vehicles forced to go off-road at various sections of the highway is unprecedented.
The dualling of the major road has been riddled with problems from its early days. In 2015, KeNHA ordered the contractor to close a diversion and construct it to required standards as it proved impassable during the rainy season.
At the time, hundreds of travellers, including tourists and truck drivers, spent the night in the cold and blamed the contractor for doing a shoddy job.
The project road is approximately 41km and forms part of the 500 km Mombasa-Nairobi highway that also constitutes part of the Northern Corridor linking the Kenyan Coast with the neighbouring countries of Uganda, Sudan and Rwanda.
It runs in a northerly direction through Changamwe, Miritini and Mazeras before terminating shortly after Mariakani Weighbridge.
The major road is faced with the challenge of a rapid increase in traffic volumes including light vehicles and heavy trucks over the years.
It is now being expanded to a six-lane highway and is largely expected to help decongest the city once completed.