The installation of a temporary roundabout on the intersection of Victoria Ave and Glasgow St has prompted calls from the public, who say traffic flow in the area has never been better, for the roundabout to be left in place.
But Whanganui District Council engineers and its infrastructure committee chairman, Alan Taylor, say the new lights are the right option.
"Most of the public aren't traffic engineers, and I'm certainly not a traffic engineer," Taylor said.
"We have very good engineers on our staff, and I defer to their knowledge in this instance. It's certainly not done on a whim."
Taylor said the decision was completely evidence based, with the flow of traffic, pedestrians and cyclists being carefully monitored.