Newly-erected bumps along the Nairobi-Naivasha highway could be partially to blame for the accident that claimed 39 lives in Karai on Saturday night.
Transport Principal Secretary Irungu Nyakera admitted there was no proper warning signage about the bumps or rumble strips at the scene of the tragedy.
There are two bumps on the section of the road where the accident happened.
"There have been complaints about the bumps and they are part of the reason why we are investigating if they caused the tragedy. We will improve on the signage at the scene and many others," said Mr Nyakera.
He said the bumps were raised in February 2016 after some locals demanded them. He said authorities would review bumps erected on major roads to ensure that there was proper signage as well as rumble strips to warn motorists.
He made the remarks in the company of Interior Cabinet Secretary Joseph Nkaissery and his PS Karanja Kibicho, Inspector General of Police Joseph Boinnet and his deputy Joel Kitili, and Kenya Red Cross Secretary General Abass Gullet.
There have been complaints that agencies at the Ministry of Transport have been erecting bumps without rumble strips and proper signage as per requirements.
In this particular incident, witnesses said the driver of the truck (a Mitsubishi Canter Reg No UAK 519C) carrying flammable materials hit a hump, lost control and hit the vehicles moving in the opposite direction before bursting into flames.
"The vehicle was not among those banned from using the road because it was not a trailer. It was a Canter with flammable materials," said Nyakera.
Trailers are banned from using the Nairobi-Naivasha highway. They are required to use the Mai Mahiu route instead.
Nyakera added authorities were looking to establish whether the transporter had adhered to all road requirements.
Lawyer Wahome Thuku was among those who complained about the bumps.
Black spot
"As you go down the highway towards Naivasha just after Kinungi trading centre, the Government has erected two bumps smack on the hill. They were put up on Thursday evening and now I can say that is a black spot," Mr Thuku said in a post on his Facebook page on February 14, 2016.
He added that there was evidence of broken glass on one of the bumps.
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"Today, we observed as motorists were forced to cut their speed from 100km/h to 10km/h in a matter of seconds to run over the bumps. Expect horrible accidents there. In fact, start preparing for a fatal crash," he said.
Between 2000 and 2016, more than 200 pedestrians have died between Naivasha and Kinungi towns along the busy highway. The majority of those killed on that section of the road have been school children mainly from Kinungi trading centre crossing the road to and from school.
Following numerous accidents, area residents held demonstrations and urged the Government to erect speed bumps on the highway. Their demands were met last year when the bumps were erected in Kinungu, Raini and Kayole centres, which saw the number of fatal accidents drop drastically.
However, one of the bumps at Raini - where the deadly Saturday night accident occurred - has turned out to be a killer, with accidents occurring there weekly.
According to James Kabono, a local leader who for years has fought for the bumps, the Raini bump was placed on a bridge, which has resulted in several accidents.
Mr Kabono said they had on various occasions raised the issue with the Kenya National Highways Authority (KeNHA) but their grievances had fallen on deaf ears.
WARNING SIGN
"There is no warning sign over this bump and speeding vehicles going downhill have lost control on various occasions, leading to fatal accidents," he said.
He added that during the Saturday incident, the truck ferrying the flammable substances hit the bump before losing control and ramming into oncoming vehicles.
"Just like in other accidents, the truck, which was going downhill, hit the speed bump and hit other vehicles, which burst into flames on impact," he said.
Yesterday, Nakuru Governor Kinuthia Mbugua and former Nacada chairman John Mututho joined other leaders in condoling the victims' families. Mr Mbugua said his government would do everything to help families of those affected by the tragedy.