One late morning last week, as a smattering of vehicles on the Nairobi Expressway zoomed unimpeded towards the city, a traffic jam on the adjacent Mombasa Road stretched all the way from Cabanas to the Southern Bypass interchange, a distance of about 10km.

These epic jams are a common sight. The causes are ordinary, including incompetent driving, taxi drivers fiddling with their phones as they drive, and devil-may-care drivers of heavy trucks lumbering along in lanes meant for faster vehicles and slowing down everyone else.

And repair work on Mombasa Road has made a normally nightmarish commute even worse in recent months.

Those heavy commercial vehicles and others heading to the Southern Bypass and beyond are supposed to divert at the Kyang’ombe exit in Cabanas and use Old Mombasa Road and other links to connect to the bypass.

Hanging on a bridge at the exit, a huge KeNHA banner with the diversion message is crystal clear. But rogue drivers couldn’t care less. The detours don’t seem to be happening, or not enough drivers are diverting to the recommended route to lessen the traffic on Mombasa Road.

But wasn’t the Nairobi Expressway supposed to help alleviate the jams? The 27km toll road officially opened in July 2022. In October 2023, Moja Expressway, the firm that operates it, said an average of about 70,000 drivers were using it every day.

Officials didn’t say whether that number was good enough (considering the Sh87 billion the government borrowed to build the road) and what level of use they expected at the planning stage. But some observers think the road is “underutilised”.

One question naturally arises: Why would so many drivers prefer to sit in their vehicles in the scotching tropical sun burning fuel on gridlocked Mombasa Road to get to the city when there’s a smooth, open highway right next to them?

The expressway lies there in its gleaming glory, beckoning to anyone clutching a steering wheel. Many of those drivers stuck on Mombasa Road could easily get on it through its several on-ramps and cruise to the city in no time.

But they don’t. Could it be the tolls charged? Are they too high? It takes about 20 minutes at 80km per hour to drive the entire 27km from Mlolongo to the James Gichuru Road exit. You’d pay a little over Sh500 for that privilege.

That’s less than three US dollars (if you want to think about it that way). The cost doesn’t seem like much, but in times of economic hardship, drivers may be asking themselves, “What else can I do with my Sh500?”

Something else may explain the expressway avoidance. It turns out that users of the road aren’t always happy customers. Often, after spending several minutes on it, they would find a clogged exit and spend even more time queueing up to pay, thus defeating the whole point of using the expressway in the first place.

While waiting times at the Museum Hill exit are notoriously long, drivers using the Haile Selassie exit face similar waits past the toll booths, trying to negotiate the Uhuru Highway or Kenyatta Avenue roundabout.

It’s hard to explain the Kenyatta Avenue roundabout logjams (some drivers blame the traffic police who control the crossroads). But at the Uhuru-Haile Selassie intersection, work is underway on a pedestrian tunnel and snarl-ups will continue into the foreseeable future.

For drivers heading to Kijabe Street and the University of Nairobi area, exiting at Museum Hill unavoidably takes them to choked Waiyaki Way, past a spaghetti of underpasses and overpasses (you blink, you miss your turn) so that they can make a U-turn hundreds of metres farther up to get to their destinations.

It makes little sense to pay hundreds of shillings to get to Nairobi quickly only to become stuck at the gateways into the city proper. As long as the disorder in the city persists, the expressway will continue to withhold its full benefits.

— The writer is a Sub-Editor with People Daily-