Poor Thika superhighway design is a threat to lives and a massive drain on the economy

What you need to know:

  • The roundabout on the Garden Estate side is so poorly designed that again large vehicles cannot negotiate it without cutting into the other lanes.
  • Road markings are an area that puts total shame on Kenyan society and a sad footnote on the level of incompetence our government officers have sunk.
  • Water and tarmac are sworn enemies. Apart from destroying the road, users are in serious danger on flooded areas.

Lots of newspaper space has recently been expended on the new Thika Road and how drivers who use it have been behaving badly.

However, a few facts about this road have been overlooked, yet they can assist us make the best use of this one of the biggest single investment in transport.

The latest news we have is that after gobbling over Sh30 billion in construction costs, the highway is taking another Sh1.1 billion supposedly in maintenance for the next one year or so.

A proposal to set up a toll station to raise funds for maintenance has even been made as if users of the road do not pay fuel levy.

The problem with this road is that it was poorly designed and this is having a big impact on maintenance costs. And for a 50-km stretch of road, the Sh33 billion construction cost was robbery.

But then that has been the trend in the construction of roads in Kenya.

Institutions such as the Architectural Association of Kenya and Institute of Quantity Surveyors of Kenya that would ideally be in the forefront in ensuring value for money for public projects have abdicated their responsibilities and only focus on the interests of their members.

POOR DESIGN

The main issue of this road is the design. As a frequent road user, I can declare that the Thika “Superhighway”, is an unmitigated disaster.

First, a fundamental component of road construction — safety — was thrown out of the design. It is inconceivable that at this time and age any engineer can design an eight-lane road without safe passageways for pedestrians.

It is now general knowledge in the transport world that speed itself does not cause accidents, it is the stopping that does. That is why in some countries, there are roads with minimum, not maximum, speeds.

It follows therefore that should one suddenly stop to turn off the highway or join the highway from a stationary position, then one is likely to be hit by another motorist.

Consequently, all highways are connected with decelerating and accelerating lanes long enough to provide the necessary safety net. Not the Thika “Superhighway”. It is a nightmare exiting or joining the road.

At all the busy junctions such as Garden Estate, Roysambu, Githurai, Ruiru and Pangani, the evidence can be seen on the damaged barriers.

The other expected truism is that you do not create a bottleneck on a highway. But on Thika road, our engineers chose to do exactly that by coming up with four lanes from Roysambu interchange up to Breweries, squeezing them to three lanes up to GSU, then opening them up again to four all the way to town.

At the Breweries turnoff from Thika towards Garden Estate, no vehicle bigger than a saloon can make the right turn without cutting into the lane of the other vehicle. It is clear the road at this section was not completed as the reserve seems to have been grabbed.

The roundabout on the Garden Estate side is so poorly designed that again large vehicles cannot negotiate it without cutting into the other lanes.

TOTALLY CONFUSED DESIGN

And it is not that the engineers needed to go far to understand good road design. All they needed was to look at Waiyaki Way from Westlands all the way to Limuru to see how safety is incorporated in design even when faced with limited road reserve.

It is very clear that the road design did not incorporate pedestrian safety at all.

The latest speed bumps near the Shell Petrol Station in Ngara at a sharp bend are an indication of a totally confused design and afterthought. What can be guaranteed is that pedestrians will now die in large numbers at this spot while accidents involving vehicles hitting the ones in front of them will increase.

A freely available traffic engineering manual from Cornwall County Council states: “Subways or over-bridges for pedestrians…are extremely expensive and require land to be available…new footbridges or subways may be considered as part of the construction of new roads, but will rarely be appropriate solutions…”

Thika Road was designed without pedestrian crossings then an added cost brought in to construct them. This is puzzling, especially given the fact that where the main road was being raised, crossings could have come in as underpasses or subways at no extra cost and minimal maintenance.

Whereas this could seem like an accidental omission, a closer look will reveal a systematic scheme to fleece the public.

NO-MAN'S LAND

First, three footbridges — Pangani, Ruiru and Thika — empty pedestrians into no-man’s land, requiring them to cross the feeder road and the Pangani one even on the highway in order to safely reach the pedestrian walkway.

Other footbridges are completely unnecessary. The one at Pangani near the river is barely 100 metres from the one I have described above and 200 metres from the Muthaiga interchange bridge.

The other footbridge at the National Youth Service is barely 300 metres from the Survey of Kenya underpass crossing.

The same can be said about the footbridge at Roysambu next to the Roysambu interchange underpass.

This problem also affects Mombasa Road following its expansion. According to the Kenya National Highways Authority (KeNHA), it will cost Sh363.1 million to put up two footbridges on Mombasa Road at Bellevue and General Motors. That is an average of Sh180 million each to cross the six lanes. They will then construct another 10 footbridges on Thika Road.

We can safely calculate the footbridges crossing the eight lanes and two-lane feeder roads on both sides to cost about Sh360 million. Ten footbridges will therefore cost Sh3.6 billion.

Are these bridges justified? All one has to do is look at where the bumps have been placed. At De La Rue, there is the GSU/Allsops bridge 300 metres away and KCA/Survey of Kenya underpass. There is no need for a footbridge here.

DEVIOUS CREATION

At Breweries, the Garden Estate bridge is 300 metres away and Safari Park footbridge another 500 metres on the other side. The bus stop is outside Naivas and a walkway has been paved from the bridge to the bus stop. The bumps should never have been erected and no bridge is necessary either.

At the new bumps in Ngara, pedestrians have Limuru road and Ojijo Road underpasses for crossing. They are both 500 metres apart in either direction from the bumps.

The bumps therefore are an ingenious and devious creation of officers wanting to give contracts for the construction of footbridges.

Ingenious because it looks like real concern for the safety of pedestrians, devious because they are experimenting with the lives of Kenyans until the death toll is so high that putting up the bridges will be taken as an emergency.

It is fact that this road has been neglected for the last two years since it was opened. The soil and bushes that are being cleared can be traced to more than a year of accumulation and growth respectively.

For the 50-km stretch from the city centre, Museum Hill and Kariakor to Thika, we can allocate one employee per day per kilometre to sweep. For a highway, we know that is not necessary as sweeping can be done every two weeks, reducing the workers to five with each covering a kilometre per eight-hour working day and the road will look spartan.

MAINTENANCE

Let us remember it has not been done in two years. However, for costs purposes, let us use 50 cleaners at Sh15,000 per month, four supervisors at Sh40,000 and a manager at Sh100,000. Add two supervisory vehicles at Sh60,000 per month.

The total costs would come to about Sh1 million per month. This works out to Sh12 million per year. Even if we gave the company a 100 per cent margin, the total cleaning costs would be Sh24 million.

On potholes, there is the guarantee money for the current period while on guard rails and lights, every car that smashes into these is insured. It is the responsibility of the highway authority to follow up these cars and have their insurance companies pay for the damage.

Road markings are an area that puts total shame on Kenyan society and a sad footnote on the level of incompetence our government officers have sunk.

Every driver knows how important road markings are. However, on Thika Road, the markings are laughable.

Starting at the Museum turnoff, one is confronted with direct arrows guiding you to drive straight onto Waiyaki Way, only it is a left turn. In fact, there are no double size dash markings that indicate to a driver that one is getting off or on to the main road.

What happens? Every other night a lorry heading to Nakuru ends up moored on the embankment separating Waiyaki Way from the turnoff.

The quality of the paint is poor, with some areas having already faded while numerous lanes are not properly closed or started, leaving drivers to guess who is on the right or wrong.

Further, the only area that the cat eyes are working is near the Pangani tunnel.

DRAINAGE

Water and tarmac are sworn enemies. Apart from destroying the road, users are in serious danger on flooded areas. For a superhighway, one would expect the designers and builders would be meticulous and almost obsessed in getting it right.

Such a dream is shattered as soon as one gets to the Muthaiga Utalii section. After the road was completed, the section flooded.

RESTORE PRIDE

We can still salvage some pride by redesigning some sections, working on the drainage, reducing the cost of maintenance, stopping the unnecessary footbridges and use international standards of distances to erect necessary ones.

Further, from now, ensure pedestrian crossings are part and parcel of any new road construction. Use the money to be saved to build other roads. No more preventable deaths and maiming of motorists and pedestrians should be allowed on this road.

Prof Maina Muchara is the director of the Kenya Institute of Governance