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THE extensive roadworks across Harare and other Zimbabwean cities under the emergency programme have already made a major difference with repairs to traffic lights now being included in some cases, as the Government hauls our cities into the 21st century.

However, we think that in many cases, at least outside the city centres, major suburban shopping centres and a few other areas, the traffic lights should not be replaced by new traffic lights but rather with roundabouts, which reportedly cost around the same price as a full set of traffic lights.

Roundabouts use more land, of course, but at many major intersections outside the inner cities, this land is available, or can be acquired under existing law at low prices since it is undeveloped or even swopped for a larger stand nearby.

Roundabouts, or traffic circles, can normally handle more traffic better than traffic lights. For a start, they tend to be self-correcting. At traffic lights you can get most of the traffic using just one of the roads and having to stop and wait for hardly any traffic coming from the right or left. At a roundabout this is automatically sorted.

Very often, and almost always outside peak hours, there is no need for most vehicles to stop. They have to slow down but can usually ease their way into the traffic orbiting the circle without long waits. That keeps things moving, literally, so increases the efficiency of the intersection controls.

Power cuts or load shedding do not affect a roundabout. While solar-powered traffic lights have been installed, there are still problems, sometimes with vandalism or theft and sometimes just the mechanical and electrical maintenance required, which is needed at any set of lights, from bulb changing upwards. The maintenance at a roundabout is often nothing much more than a worker with a shovel and a broom, or a pair of shears for the centre shrubs during the growing season, and even that is only occasional.

Roundabouts are also not seriously damaged by accidents or vandalism. A car, let alone a heavy truck, will frequently seriously damage or destroy the particular light it hits in an accident, while on a roundabout there might just be some wheel tracks over a flower bed that can be fixed almost instantly. There is not much to damage or destroy if vandals hit a roundabout.

Zimbabweans have fallen into the very bad habit at night of almost ignoring red lights, the excuse being security although no one has actually seen the criminals allegedly hanging around intersections waiting to pounce. But even if they do gather once people obey traffic lights, a roundabout means the traffic keeps moving legally and safely.

So it seems to us that it would be a useful move forward if the Ministries of Transport and Infrastructural Development and of Local Government and Public Works, set down as a joint policy that roundabouts were to be used at all major intersections as the default norm, with traffic lights reserved for city centres and special needs, only to be used when a roundabout was impossible to site.

Mbudzi roundabout may have given the genre a bad name, but even at this exceptional intersection, it was a vast improvement on traffic lights, and just showed up that even the best of the cheaper solutions has a limit, hence the need to upgrade to the multi-level interchange.

One major set of roadworks in Harare in progress at present is the upgrade of many sections of Harare Drive and of the arterial roads that cut across this ringroad 10km from the city centre. There are traffic lights on many of those intersections, often not working, and it seems that these particular intersections seem an obvious place to start the switch to roundabouts.

Other safety policies could be enforced on roads as construction, rehabilitation and upgrading are done. Speed humps are seen as a simple solution to slow traffic for schools, pedestrian crossings at shopping centres and even for entering intersections.

Some thought has been given to these in recent years, so we have been moving away from the half-cylinder across the road that smashes sumps to the far lower and flat rectangular hump and now to the rumble strips, which seem to be developed from the old system to warn and slow traffic approaching a rail crossing and a return to that useful design. They are used these days for the approaches to toll gates and serve the same warn and slow process.

It should be possible with a bit of experimentation to design suitable quasi humps and rumble strips that are speed specific. In other words, if the safety engineer wants to reduce the speed to say 40km/h, then it should be possible to have specially designed 40km/h speed strips, that is someone at that legal speed would not even have to slow down. Getting speed humps to this level of precision would remove many objections, as even the worst driver recognises that driving very fast outside a school is a bad idea.

Speeding will become a problem as we get better roads, some drivers feeling they are entitled to speed, others not noticing that they might be going too fast. In several developed countries, automated unstaffed speed traps have been developed. These are placed on the roadside and take a photo of the registration plate of a speeding vehicle. The humans just send the photo, the speed record and the fine demand to the registered vehicle owner. After an initial burst of fines, most drivers learn not to speed.