Roundabouts were designed to get you to slow down and pay attention. Photo | File
In the early-to-mid 2000s, traffic flow in Kampala was like experiencing a new dawn since all roundabouts were being replaced by traffic lights. There had been unbearable traffic jams, which all seemed to start at roundabouts. Most notable among the roundabouts that were eliminated is the one that used to be at Centenary Park/Electoral Commission, where the Jinja road lights stand. It was tiny, bushy and had a small tree in the centre. When it was replaced with traffic lights, the area looked modern, open and spacious and generally looked like a cure to traffic jams at this busy Kampala city intersection.
However, it did not take long before traffic gridlocks returned to rival or even surpass the ones before the traffic lights. Long story short, traffic police permanently stationed themselves at the spot and took up the job of controlling traffic.
In 2015, Kampala Capital City Authority (KCCA) replaced even more roundabouts with traffic lights. All these traffic lights that replaced roundabouts for purposes of easing traffic flow are now manned by traffic police, while also not reducing traffic jams considerably.
Comparatively, the Kibuye Roundabout on Entebbe Road is equally busy but it mostly runs without the need for traffic police officers to help out with traffic flow. Traffic flow there may be slow sometimes, but it barely ever grounds to a halt, which is the case at Jinja Road traffic lights, Wandegeya or Fairway on Yusuf Lule Road.
This begs the question, was it a miscalculation for the government to remove the roundabouts? Should they have made them bigger and more advanced such as the ones all on the Northern Bypass and the Kampala-Entebbe Expressway? Are roundabouts better at controlling traffic flow than traffic lights?
A study in the United States (US) by the Federal Highway Administration (FHA) found that roundabouts are better at controlling traffic than traffic lights. This is because they increase traffic capacity by 30 to 50 percent, compared to traffic lights, reducing congestion and delays caused by red lights and stop signs, according to the body.
For this reason, roundabouts have been gaining popularity in the US over the last two decades. Interestingly, the first modern roundabout in the US was built in Las Vegas, in 1990, more than 30 years after roundabouts became ubiquitous in Europe. Since 1990, the construction of modern roundabouts in the US has increased, with more than 10,000 roundabouts in the country, according to the FHA.
They have become so trusted that in the US the FHA recommends them as the safest option. Some states such as New York and Virginia have adopted a “roundabout first” policy, where road engineers are required to build roundabouts whenever building or upgrading intersections.
Some technologies, such as the good old wheel, cannot be improved upon or reinvented. They are just perfect because they work. This seems to be the case with roundabouts. They seem to be the perfect solution to traffic problems at intersections.
A brief history of roundabouts
As early as the 1700s, some city planners proposed and even constructed circular places, sites where roads converged, such as the Circus in Bath, England, and the Place Charles de Gaulle in France. In the US, architect Pierre L’Enfant built several into his design for Washington, DC. These circles were the predecessors to roundabouts.
In 1903, French architect and influential urban planner Eugène Hénard was one of the first people who introduced the idea of moving traffic in a circle to control busy intersections in Paris.
Around the same time, William Phelps Eno, an American businessman known as the father of traffic safety and control, also proposed roundabouts to alleviate traffic congestion in New York City.
In the years that followed, a few other cities tried out a roundabout-like design, with varying levels of success. These roundabouts did not have any sort of standardised design guidelines, and most of them were too large to be effective and efficient, as vehicles would not need to slow down to enter them.
Yield at entry
The birth of the modern roundabout came with yield-at-entry regulations, adopted in some towns in Great Britain in the 1950s. With yield-at-entry regulations, the vehicles entering the roundabout had to give way to vehicles already circulating in the roundabout. This was made a rule nationwide in the United Kingdom in 1966, then in France in 1983.
Yield-at-entry meant vehicles drove through these modern roundabouts more slowly, and over the years, engineers began adding more features that made them look closer to how roundabouts do now. Many added pedestrian crossings and splitter islands, or raised curbs where vehicles entered and exited, which controlled the vehicles’ speeds.
Engineers, planners and decision-makers worldwide noticed that these roundabouts improved traffic flow, reduced congestion and improved safety at intersections. Roundabouts then spread throughout Europe and Australia.
Three decades later, modern roundabouts were introduced to North America, with the first modern roundabout being built in the US in 1990.
Benefits of roundabouts
Roundabouts likely caught on so quickly because they reduce the number of potential conflict points. A conflict point at an intersection is a location where the paths of two or more vehicles or road users cross or have the potential to cross. The more conflict points, the more likely vehicles are to crash.
At roundabouts, vehicles do not cross each other at a right angle, and there are fewer points where vehicles merge into each other.
The roundabout’s tight circle forces approaching traffic to slow down and yield to circulating traffic, and then move smoothly around the central island. As a result, roundabouts have fewer stop-and-go issues, which reduces fuel consumption and vehicle emissions and allows drivers to perform U-turns more easily. Since traffic flows continuously at lower speeds in a roundabout, this continuous flow minimizes the need for vehicles to stop, which reduces congestion.
The FHA estimates that when a roundabout replaces a stop sign-controlled intersection, it reduces serious and fatal injury crashes by 90 percent, and when it replaces an intersection with a traffic light, it reduces serious and fatal injury crashes by nearly 80 percent.
But roundabouts are not needed in every intersection. In places where congestion is not an issue, city planners tend not to push for them.
How to drive
• Be patient. Roundabouts were designed to get you to slow down and pay attention; the very things that prevent car accidents.
• Yield to pedestrians. In a typical roundabout, you will find crosswalks before approaching the roundabout. Next, yield to any vehicles currently in the roundabout. Cars in the roundabout always have the right-of-way.
• Remember to use your turn signals. Indicate right if you are making an immediate right-hand turn. You do not need to use a signal if going straight. • Some roundabouts may have several lanes. If you encounter one like this, make sure you are in the correct lane before entering the roundabout. Choose the right lane if you are making a right-hand turn or going straight. Pick the left lane for left and u-turns. Whatever you do, do not attempt to change lanes while in the roundabout.
Source: ladenburglaw.com
Adapted from the conversation
