The problem with the roundabout came to the attention of the transport agency when a number of drivers called in to say that drivers approaching the limit line were not giving way, as required, to vehicles circulating on the roundabout.
A driver who uses the roundabout, but wished to remain unnamed, said the markings still caused confusion for him.
Bay of Plenty Driving School instructor Jeroen van der Beek said the markings made only partial sense.
"I can see the logic on the spirals but only for vehicles turning right off the state highway on to Oropi Rd. It throws you to the left lane to exit.
"But it doesn't take into account people coming from the other roads. It confuses drivers, especially coming to the roundabout for the first time, on what they should do.
"Coming from Oropi Rd on to the roundabout you have no idea if you should follow the lines and get thrown to the outside or cross traffic and stay on the inside," Mr van der Beek said.
"If I was coming from Oropi Rd I would probably go on to the outside circle, but once I had studied them I would probably ignore them and stay on the inside."
He said it was not clear what the designers wanted.
"It solves a small issue but creates a bigger one."