The path of least resistance?

Where I live we have three types of thoroughfares: roads, shared-use paths (commonly known as bike paths) and sidewalks.

Roads are for motor vehicles and bikes; pedestrians if there are no adjoining sidewalks. Sidewalks are for pedestrians and bikes (unless buildings abut the sidewalk, in which case bikes are prohibited). Bike paths (officially known as shared-use paths, even though some have “bike path” in their names) are for bikes, pedestrians, joggers, skaters, skiers, equestrians…

How do bikes fit into all of this? Some of the trails are toll roads if you’re on a bike but not if you’re walking. We have no toll roads for cars in this state. I have seen rants in the newspaper (or heard them from people) that bikes don’t belong on rural roads – they should stick to the paths. I’ve heard rants that bikes don’t belong on other roads because they go too slowly. I’ve seen rants (on a neighborhood app) about bikes that go too fast on the paths. And I’ve seen claims that bikes on sidewalks are illegal (as noted above, they are illegal in only a very limited downtown area where I live).

So where does that leave bikes? Not wanted on the roads, not wanted on the paths, not wanted on the sidewalks. Too slow for the roads, too fast for the paths, just plain dangerous on the sidewalks.

I have written before about John Forester‘s concept of vehicular cycling. Back in April of 2018 I wrote a series of posts about bike safety. This time, I’m here to talk about the conundrum. Our society has not yet decided whether to consider bikes toys or a mode of transportation; partly because there is no reason they can’t be both. How we are using a bike should be a determining factor in where we ride. Generally I prefer to ride lightly-traveled streets – both in town and in the country. Whether going fast or slow they seem to work best. (Jarjour, et al in Environmental Health, 2013, found lightly-traveled bike boulevards reduced cyclists’ exposure to environmental pollutants from vehicle exhaust – a result that should make you say “duh”, but should also make you rethink riding on busy streets.)

The purpose of traffic laws is to standardize and define relationships and expectations among users in order to increase safety. In grey areas, the most vulnerable user should have the right of way.We are responsible for each other’s safety and ultimately we are all responsible for our own safety. A law will not protect us from a multi-ton vehicle. Common sense should be our guiding principle.

Drivers are often advised that it is safest to drive at or near the prevailing speed of traffic rather than strictly at the speed limit; thus they may be going slower or faster than the posted speed at times. Going faster is always illegal, regardless of the “prevailing speed”.

Q. Isn’t slower always safer?
A. No, federal and state studies have consistently shown that the drivers most likely to get into accidents in traffic are those traveling significantly below the average speed. According to research, those driving 10 mph slower than the prevailing speed are more likely to be involved in an accident
.” https://www.motorists.org/issues/speed-limits/faq/

“It has been found that motorists are generally capable of determining the driving speed that is reasonable for prevailing road and traffic conditions unless there are some roadway conditions that they are unaware of or which are not readily apparent and that the majority will subsequently adjust their speed accordingly. The 85th percentile speed, the speed at or below which 85% of the vehicles travel a particular roadway, has been found to best represent this perceived ‘reasonable’ speed.https://wisconsindot.gov/dtsdManuals/traffic-ops/manuals-and-standards/teops/13-05.pdf

I would argue that 85% of motor vehicles exceed the speed limit on 25 mph residential and urban streets. Yokoo, et al (Traffic Injury Prevention, 2019) found that “speeding is widespread…” in Minneapolis/St Paul. Hu and Cicchino (Injury Prevention, 2020) and Jones and Brunt (Journal of Epidemiology and Community Health, 2017) argue for speed limit reductions in Boston and Wales, respectively. Apparently motorists can determine the safe speed but that doesn’t mean they/we adhere to it. The 85% rule appears to be most applicable for highway speeds.

 Urban shared-use paths require care and vigilance. Travel slowly enough not to spook other users and to be able to react to their sudden moves. Calling “On your left” frequently results in pedestrians looking over their left shoulders while unconsciously moving to the left into your path. That’s why I use a bell in the city (and most of my bike path use is at 6 AM when there are few people walking). People seem to do better at localizing the sound of the bell and moving appropriately. I have no evidence to support this beyond personal experience. (Lack of evidence is not the same as evidence against. It just means I can’t find that anyone has studied this.) The Next Door app in my neighborhood is currently exploding with a thread about e-bikes on shared-use paths.

The same standard that applies to motorists appears safest for bicyclists. If you are going to be traveling fast, stay on the street (or rural paths that are known to be used primarily by bikes). If your town has “bike boulevards”, they tend to be safer, with infrastructure designed (sort of) or retrofitted for bikes. (Walker et al. define bicycle boulevards as “low-volume and low-speed streets that have been optimized for bicycle travel through treatments such as traffic calming and traffic reduction, signage and pavement markings, and intersection crossing treatments.” [Fundamentals of bicycle boulevard planning & design. Prepared for the Portland State University Initiative for Bicycle and Pedestrian Innovation.2009])

Eric Minikel studied bike boulevards in Berkeley, CA, comparing them to adjacent streets and found:
“Using police-reported collision data and the city’s cyclist count data, this study finds that Berkeley’s bicycle boulevards do indeed have lower collision rates for cyclists than their parallel arterial routes. This is true for all six bicycle boulevard–arterial pairs for which data are available, with risk ratios ranging from 1.8 to 8.0. This is true whether only reported bicycle–motor vehicle collisions are examined or bicycle–bicycle, bicycle–pedestrian and single- cyclist incidents are included as well.” (Accident Analysis and Prevention, 2012)

If you are going to be traveling slowly, use urban paths. Personally, I see very few times that a sidewalk is safe. Motorists backing out of driveways (or turning into driveways) are not looking for bikes. They are not looking for anyone traveling faster than walking speed. Small children on bikes may be going at walking speed, but are so low as to be all but invisible to motorists. Learning to ride a bike on the sidewalk in front of your house may be fine, but traveling any distance on a sidewalk is probably not very safe for a young child.

Forester recommends riding like a vehicle – stay right except to pass, turn left from the left lane. He essentially argued that bikes should be integrated with motor vehicles and that separate bike lanes cause more dangerous situations at the inevitable intersections between bike and car – e.g. bikes turning left across multiple lanes of traffic from a bike lane on the right, cars turning right across bike lanes going straight. A completely separate bike path inevitably intersects roads, and motorists who have learned to be unaware of bikes (since they are not on the roads) will inevitably be more dangerous when they do have to meet. Apologies to Forester if I misrepresent him by merging my thoughts with his.

I would argue that bike paths have their place and that they require the same style of riding as do streets – with the understanding that the other “vehicles” with which you are sharing the road are roller bladers, kids, strollers, dogs, beginning riders; instead of cars and trucks. I think he is right that bike lanes create a false sense of security and result in greater danger (cars parked in the bike lane, parked cars opening doors into the bike lane, cars in right turn lanes turning right across the path of bike lanes that continue straight). I would argue that riding as close as practicable to the prevailing speed of traffic is safest – thus slower on shared-use paths and faster on roads.

While this column did not start as an argument for bike boulevards, they seem to deserve serious consideration. In many cities there are parallel roads. I would argue for using the less-traveled route while on a bicycle. Minikel shows that crashes are less-frequent on bicycle boulevards than on adjacent routes, but is this due to the boulevard infrastructure or just the relative dearth of traffic? Where one route is less-traveled than another, common sense would hint that the less-traveled route is safer for bikes. Is the infrastructure a major determinant? Mulvaney, et al (Cochrane Database Systematic Review, 2015) set out to determine whether infrastructure could be credited for increased safety. They concluded “Generally, there is a lack of high quality evidence to be able to draw firm conclusions as to the effect of cycling infrastructure on cycling collisions. There is a lack of rigorous evaluation of cycling infrastructure.” They judged the quality of most evidence as low and preliminarily hinted that 20 mph speed limits may help and that roundabouts may be dangerous for cyclists.

Personally I tend to avoid urban shared-use paths because I have to treat every intersection as a yield sign in order to protect myself from cars, and I have to ride more slowly than I’d like to when commuting during daytime hours when others are out. There are routes where the street alternative is worse, so I choose routes on a case-by-case basis. (And some are too pretty not to ride on.) My daily routes to and from work were chosen by trial-and-error and adapted over time.

As in almost everything I read for work, “further study is warranted” and “there is a dearth of quality evidence”. As always, common sense should be your guide, and common sense is less common than it ought to be.

As Rodney King (1992) asked, “Can we all get along?”