Lane Sharing, What Is It?

Throughout Europe and Asia, and many parts of Australia, motorcycles are allowed to travel in the spaces between lanes of traffic moving in the same direction on multi-lane roadways, with motorcycles traveling in the unused space between the lanes of vehicles on the roadway.  As can be seen in this photograph of traffic on a California highway, there is more than enough room for motorcycles to pass between the lanes of traffic.  This practice allows motorcycles to move through the traffic flow in a safe manner, instead of under using the space that could otherwise be used by a larger vehicle in traffic.  There is often a space of 4 to 6 feet between the vehicles in adjacent lanes.  With motorcycles generally being little more than 2 feet in width, there is normally plenty of space for motorcycles to pass between. 

California is currently the only state in the US that allows lane sharing.  While it has been allowed for many decades, it was only in 2016 that it was actually codified in the California Vehicle Code.  In 2013, the California Highway Patrol issued a set of guidelines that had been worked through amongst state agencies and other organizations that had a stake in the transportation field within the state of California.  It took several years of negotiation to reach the final guidelines published by the CHP.  However, a state employee filed a complaint with the state, claiming that since the practice was not codified in law, the CHP was attempting to illegally create new law by issuing the guidelines.  The CHP then withdrew its guidelines, and joined in the effort to actually study the issue so that it could be made into law by the California state Assembly.

In both the 2014 and the 2015 studies done by University of California Berkeley for the State of California, some rather surprising findings came to light that could affect the movement to bring lane sharing/splitting to other states as well.  Overall, the reports brought out several key pieces of data that demonstrates just how safe the practice actually is for motorcyclists.  Even at higher traffic speeds than is generally sought in many bills brought before state legislators.  The sampling for these studies was significantly higher than in many previous studies on motorcycle safety.  Roughly five times larger than sampling for the famous Hurt Report of the 1980's that is generally regarded as the most in-depth study of the 20th Century.  This large sampling showed quite positive results regarding the safety benefits for motorcyclists who chose to lane share/split.

A 2012 study by J.V. Ouellet showed that the percentage of motorcyclists who lane share/split dropped significantly once traffic speeds reached 40 mph.  This falls in line with the guidelines build into legislation proposed by ABATE of Washington that will be introduced in the Washington State Legislature in January, 2017.  While lane sharing may not be for everyone, it has benefits for everyone on the road.  In a 2011 study from Belgium, it was shown that a small modal shift to a ratio of 10% motorcycles to 90% motor vehicles, would reduce overall traffic congestion by 40%.  While that modality shift may be possible, in a state with the climate similar to that of Washington State, it is unlikely.  At least not year round.  However, what can be much more likely, and still effective, is to allow lane sharing by those motorcyclists already on the roadways.  

Imagine for a moment all of the motorcycles in the photo to the left remaining each in its normal position within the traffic flow.  Each of these motorcycles would have been taking up road space enough for a car or a truck.  But, by lane sharing, the rest of the traffic can move forward and fill all of that now vacant space.  This allows all the highway users to move, and reduces the overall congestion period significantly.  With virtually zero expense for new infrastructure needing to be built.

The lane sharing studies carried out in 2014 and 2015 both showed that it is a safe practice.  Those taking part in the practice involved in fewer crashes, and with fewer and less severe injuries.  This corresponds nicely with findings from the MAIDS 2009.  That study from Europe found that only 0.4% of motorcycle accidents were lane sharing related.  It also found, as did the two California studies that injuries were less severe as well.  According to the 2015 study, those lane sharing motorcyclists who crashed  suffered; almost one half the number of head injuries, a third as many torso injuries, and less than half as many fatalities.  The 2015 California study actually states that lane sharing; "appears to be a relatively safe motorcycling strategy if done in traffic moving at 50 mph or less and if motorcyclists do not exceed the speed of other vehicles by more than 15 mph."  The bill being introduced in the legislature would create a maximum speed of traffic at 25 mph, as well as a maximum speed differential of 10 mph.  As you can see, well within the safety limits described by the 2015 lane sharing study.

When used with just a little common sense riding, lane sharing is as safe as any other technique sued by motorcyclists.  As this image demonstrates, the motorcyclists doesn't have space enough to pass between the two trucks at this point, so is applying his brakes to stop between traffic behind the trucks.  With a slight bit of patience, space will open up, and the rider will be able to pass by both trucks in what the CHP calls a "safe and prudent" manner.

The Washington State Patrol is even given the authority in the bill to create training and educational materials on lane sharing.  It is a technique that will require some public

education of motor vehicle operators to insure the public is aware the practice would be legal, as well as guidelines such as the CHP created for motorcyclists in California.

The WSP is familiar with the practice as well.  Allowing law enforcement officers to pass between lanes of traffic in the performance of their duties is already part of the current RCW.  The public hasn't been exposed to any media reports of law enforcement motorcycle officers killed or maimed on the highways of Washington State.  All of these reports explain why that is the case.  With just a modicum of skill and common sense, lane sharing is a safe and sensible technique used around the world successfully.  It is high time it is made available to citizens of Washington State.

Catch you on the road sometime...