Roundabouts: A curse or a cure for congested intersections?
That was the question recently answered by Adam Savage and Jamie Hyneman, the highly entertaining hosts of the Discovery Channel’s popular “Mythbusters” program.
If you’re not familiar with it, the program uses scientific methods to test the truthfulness of rumors, myths, historical “facts,” news stories, movie scenes and more.
Since 2003 Savage, Hyneman (who hails from Marshall) and their backup crew have tested hundreds of hypotheses to determine if they were valid, plausible or just plain busted.
Will you stay drier walking through a rain storm rather than running though it? Can you manufacture diamonds in a microwave? Can you make a working cannon out of duct tape? How easy is it to shoot fish in a barrel? (In case you’re wondering, the answers are: plausible, busted, yes and kind of true because while it’s difficult to shoot the fish they still die from the shock wave. Incidentally, they used plastic fish and then counted the hits.)
In August they tested the efficiency of a four-stop intersection versus a roundabout.
Here’s how: In a huge parking lot they they used construction barricades to build a single lane approach to a four-way stop intersection.
Drivers of the 40 test vehicles were instructed which way to go (left turn, right turn or straight through when they came to a stop.) Drivers continued to loop back into the intersection for two 15-minute test periods, with Hyneman keeping count to arrive at an average.
For the roundabout the barricades were formed into four approaches formed around a center island.
Drivers were allowed to practice driving in and out of the roundabout for 30 minutes since most Americans aren’t used to roundabouts. The drivers then drove in and out of the roundabout for two 15-minute test periods during which Hyneman again kept count for an average.
OK, I could be horse’s heinie and tell you to watch the “Mythbusters” episode at www.wimp.com/testroundabout/ for the results, or I could just give them to you.
The four-way intersection with stop signs averaged 385 vehicles moving through over a 15-minute period. The roundabout averaged 460 vehicles for the same time period, which “Mythbusters” said was about a 20 percent increase in traffic movement.
There are a lot of drivers out there who fear and loathe roundabouts, mainly because they don’t understand them. It’s pretty simple really: If you can drive in a circle, you can drive in a roundabout.
To enter, yield to oncoming traffic or just pull in if the way is clear.
Traffic only moves to the right.
Exit/entrances are every 90 degrees, so all you have to do is exit to the right. If you miss your exit just continue on the roundabout to circle back to your exit.
Roundabouts eliminate T-bone and front end crashes. Any crash that does occur is minor because speeds inside roundabouts are usually limited to 25 mph and both vehicles are traveling in the same direction.
Here’s another reason to become comfortable using roundabouts: There are more of them on the way.
Oakland County has 24 of them and the road commission is slated to build a huge roundabout at 14 Mile/Orchard Lake Road beginning in 2014. Macomb and Wayne counties have them, too.
Do not fear the roundabout, embrace it. The roundabout wants to be your friend.