Roundabout interchanges being proposed for the future Loop 202 intersections at McKellips and Brown roads address residents’ complaints and engineering problems, a state transportation consultant said Wednesday.
In a roundabout, traffic trying to enter the freeway or cross it would have to yield to vehicles leaving the freeway on a paved circle.
Arizona Department of Transportation consultant Steve Wilcox told Mesa’s Transportation Advisory Board that ADOT is proposing roundabouts because conventional interchanges are more difficult to design. In a conventional interchange, the angle would create visibility problems for drivers.
Also, residents were unhappy with the conventional interchange because the surface streets would have to be raised above the freeway and a canal bank. Residents said that would obstruct their views and create noise problems.
Wilcox said he met recently with a core group of residents.
"We got very good feedback with residents, and they were pleased with the design and thought they were fitting alternatives for McKellips and Brown roads," he said.
Roundabouts are used widely in Europe and in some parts of the United States, but the only such intersection on a Valley freeway is at Interstate 17 and Happy Valley Road.
Wilcox said the roundabouts are: They’re $1.3 million cheaper to build, can handle more traffic because they don’t have traffic signals, and are safer because speed averages 15 to 20 mph.
"If there are accidents, they’re just fender-bender types rather than people trying to beat the signal," he said.
Transportation board chairman Don Grant said he had to drive through the roundabout at Happy Valley a couple of months ago, and "I absolutely hated it. I came up on it and had no idea what to do with it."
Others said they were concerned people would drive too fast; winter visitors would not understand them and they would be hard for pedestrians to cross.
Wilcox said more resident meetings are planned, and in April, a presentation will be made to the City Council.