Anadromous salmon spend the last part of their lives swimming upstream/ against the flow. Pedestrians in the United States are taught and legally obligated to walk against the flow of traffic-see Wis. Stat. §346.28.
|photo credit http://tashjusttash.com|
Bicyclists however are treated as vehicles and should generally ride on the right side of the roadway-see Wis. Stat. §346.05. Because people fear getting hit from behind, some choose to ride their bicycles against the flow of traffic.
Even though riding against traffic may decrease the chance of getting struck from behind, riding a bicycle against traffic is considered less safe than riding with traffic for many reasons.
First, Motor vehicle drivers pulling out of parking lots etc. and or making a right turn will often only look to their left because they are looking for things that can harm them (other motor vehicles), and also do not expect traffic approaching from their right.
Second, a collision between two vehicles traveling in opposite directions often results in higher impact speeds than two vehicles traveling the same direction. Because of the opposite direction of travel, there may also be less time to react.
Third, bicycling against traffic makes right turns difficult for the bicyclist due to position on the roadway.
Fourth, bicycling against traffic can result in two bicyclists approaching each other from opposite directions inside a bike lane.
In “Comparing the effects of infrastructure on bicycling injury at intersections and non-intersections using a case–crossover design,” , Inj Prev 2013;19:303-310 doi:10.1136/injuryprev-2012-040561 by M Anne Harris, et. al, the authors concluded that:
“We included a variable indicating whether the cyclist was travelling in the opposite direction to motor vehicles and found it to increase risk at intersections significantly.”
|photo credit http://humantransport.org/ncbikeed/|
In “Risk Factors for Bicycle-Motor Vehicle Collisions at Intersections,” ITE Journal, published by the Institute of Transportation Engineers, September 1994, pages 30-35, by Alan Wachtel and Diana Lewiston, the authors concluded that getting hit from behind while bicycling is a rare type of collision:
“Overtaking accidents, in which a bicyclist in the roadway was struck from behind by a motorist traveling in the same direction, accounted for only 5 of 314 bicycle-motor vehicle collisions.” The authors also concluded that: “All categories of bicyclists traveling against the direction of traffic flow are at greatly increased risk for accidents-on average 3.6 times the risk of those traveling with traffic, and as high as 6.6 times for those 17 and under.” Id. “Wrong way bicycling is risky at an overwhelmingly high level of significance.” Id. “Wrong way bicycling is dangerous for all subgroups of bicyclists, including those traveling on the sidewalk who may at first seem to be protected against collisions with motor vehicles.” Id.