Which lane do you use at traffic lights?
You’re approaching an intersection with traffic lights and three lanes to choose. There’s a right lane, and then a centre and left lane.
If you choose the left or centre lanes, you’ll need to zip merge after you’ve crossed the intersection. But the right lane has the longest line of traffic waiting to get through the intersection.
So, which lane would you choose? Take our poll and then find out what you should do.
What you should do
While many people believe using the left lane, which is often empty, is pushing in, this isn’t really the case.
RAA Senior Traffic Engineer Matt Vertudaches says an extra lane either side of an intersection, similar to the below example, can help allow more traffic to cross during a cycle.
“Using all through lanes and zip merging correctly maximises traffic flow and the number of vehicles that can pass through an intersection,” Matt says.
“This means it’s important for drivers to use all through lanes and zip merge correctly, giving way to the vehicle in front at the merge point.
“While there might be a bit of a lag at the zip merge point, it still allows more vehicles through the intersection on the green light and reduces queue lengths for the next green light.
“If you move across earlier than required, this can shorten the distance to the zip merge and impact traffic still passing through the intersection.”
Some motorists will use the right lane to avoid merging after crossing the intersection. This can cause longer lines of cars waiting to cross the intersection. In some cases, motorists might even have to wait for an extra cycle at the traffic lights.
“When all lanes are used evenly, the total queue length is shorter, meaning fewer vehicles block upstream intersections or driveways,” Matt says.
“This improves overall network efficiency and helps traffic signals operate as intended.”
Some new intersections even have the above signage, encouraging motorists to use all lanes. A sign like above can be found on Portrush Road when approaching Magill Road.
Matt says courtesy also plays a part in these situations. When traffic is quiet and already flowing smoothly through the intersection, speeding down the left lane to merge one or two cars ahead is not going to improve traffic flow and can increase the risk of a collision,” Matt says.
“There’s no road rule preventing drivers from using an available lane, and what matters is how they merge afterwards.
“When merging, do it smoothly – not suddenly or aggressively, and leave space for the vehicle in front of you to merge.”