Tom Burrows
Version 3.0
August 13, 2013
This paper discusses some common street and road design flaws and maintenance issues that create safety problems with respect to bicycling. I shall concentrate mostly on examples from the neighborhood where I live—between South Camp Road and the Colorado National Monument boundary (Mesa County, CO).
Some of these problems and their respective solutions are, at first, not intuitively obvious to planners and novice cyclists. This is why so many planners get things wrong, here and elsewhere.
Fortunately, substantial improvements can be made that require only simple changes to the existing roadways and/or improved maintenance procedures. For the most part, what is needed to make streets and roads in this area bikeable is not more money or special facilities, but a reversal of misguided past decisions and avoidance of similar mistakes in the future.
In 2006, the Mesa County Public Works Department and the engineering firm Schmueser Gordon Meyer produced a flyer entitled Monument Road Widening Initiative, which described a project to address "safety and drainage issues along Monument Road." The #1 bullet item on the list of improvements was
"The road will be widened along the entire length of the project area to accommodate bikers."
The road was indeed widened; but design and maintenance issues perpetuated safety problems for both motor vehicles and bicycles. I brought these issues up during an open house for public comment; but they went unaddressed and the results have been exactly as I feared.
Many (perhaps most) of the bike riders on Monument Road seem to be avoiding the bike lane and are riding in or close to the auto lane, which forces cars and trucks overtaking them to swerve into the oncoming lane to get around them. I assume the debris in the bike lane is the reason for this.
It is a law of physics that bicycles depend on passing motor vehicle tires to keep the road surface swept clean of gravel and other debris. This works only if both motorized and non-motorized vehicles share the same lane. Debris disturbed by passing motor vehicle tires migrates off to the side onto whatever surface is there. Walking along Monument Road and examining the roadway, you can clearly see the portion of the roadway the car tires are cleaning—and how the debris builds up in the "bike lane" that has been marked to keep car tires out.
There are two ways to address this problem:
Eliminate the painted line between the auto lane and the bike lane so that 1) when bikes are not present, motor vehicle tires can keep the entire surface clean and 2) when bikes are present, the entire lane is wide enough to be safely shared.
Clean the bike lane routinely with a street sweeper. This must be scheduled frequently enough that the debris doesn't build up to the point that bicyclists go over toward the auto lane to avoid tire punctures.
The most obvious problem with Method #2 is the ongoing cost of running the street sweeper.
Method #1 is recommended by vehicular cycling advocates like John Forester, author of Effective Cycling. I can personally attest to the benefits of this method, having commuted to work by bicycle for many years (in Illinois) on a high-speed highway with a wide shared lane—just like Monument Road but without the painted line. Some complain that this method without the line is more psychologically intimidating to bicycling novices—a "novice" being someone who does not know how to correctly operate a bicycle as a vehicle in traffic and would prefer to treat it as a recreational device (i.e., plaything). Novices are not necessarily children. Much of the novice behavior I observe is from adults riding expensive-looking gear and wearing complicated colorful outfits.
Such novices do not belong on light-duty thoroughfares, either. They are a danger to themselves and others even when they are on side streets (where they still have to interact with other vehicles) or on off-road trails and sidewalks (where they have to interact with pedestrians and with one another). The solution to the problem of novice cyclists is to educate them in techniques like Forester's effective cycling instead of herding them into play-pen-like bike lanes or paths, which only serve to perpetuate the myth that it's OK to treat bicycles as toys rather than as vehicles.
A couple of years ago, the side streets in my neighborhood (and probably others) were resurfaced, and in my opinion ruined, using a process that coats the road with tar and then covers it with a layer of large (pea-sized) pointed and sharp-edged stones instead of conventional gravel. Early Man made sharp edges for spear points and defleshing knives by chipping away at rocks. The "chip seal" on the local roads contains chips resembling 1/4"-1/3" replicas of these edged tools and weapons.
Even after several attempts to clean it with street sweepers and a couple of years of car traffic, the surface is still littered with loose stone tools/weapons. To make matters worse, the tools/weapons glued permanently into the tar form a surface like ultra-coarse sandpaper with BB to pea-sized grains of cutting grit. This cannot be good for bike tires...or anyone's body if they were to fall onto this at normal biking speeds. Not even counting the loose stuff, the spear points and knife blades that are now a permanent part of the surface are an order of magnitude worse (in size, quantity and sharpness) than the gravel in the Monument Road bike lanes that cyclists are avoiding.
The only reason I can imagine for this sort of road treatment instead of traditional tarring-and-gravelling would be that the big sharp stones on the surface provide great traction—at least as long as packed snow or ice is less than 1/4 inch thick.
In addition to the aforementioned problems involving marked bike lanes, South Camp Road has several additional problems.
The most dangerous of these problems is that in some sections there is a marked bike lane on only one side (westbound). In addition to the problems with marked bike lanes in general, having such a lane on only one side may tempt novice riders (heading eastward) to, at their peril, use it to ride down the wrong side of the road.
I also found examples of the spear point and knife edge chip seal treatment on South Camp Road. This problem is exacerbated by yet another problem with marked bike lanes: Out in the roadway, the sharp points and edges are gradually being dulled by the passing of thousands of motor vehicle tires; but in the marked lanes, the points and edges are as sharp as the day they were glued down. Street sweeping is, of course, of no use here.
Along South Camp Road there are pedestrian sidewalks, which bicyclists may be tempted to use. Some of these sidewalks are concrete and some are blacktop. The blacktop sections are falling into disrepair—presumably because of an inadequate base. Soils in this area are soft sand; and a full-fledged road-type base is required or the pavement will fall apart. The concrete section is in good repair; and I'm told it does have a proper base. Unfortunately, the seams every few feet feel like speed bumps for a bike with high-pressure road tires. I tried biking on it once, and got tired of the whump-whump-whumping after a couple of blocks.
As was suggested above, bicycles are vehicles and for safety reasons should not be mixed with pedestrians; and this is probably an even bigger reason these sidewalks should not be used as alternatives to just biking on the road. Where I used to live in Illinois, there was a mixed-use, off-road biking and hiking trail along an abandoned rail easement. I found it to be unusable because it was a magnet for people (especially reckless children) who did not know how to ride properly. I rode on it occasionally, but quickly gave up. The motorists were easier to deal with. This is an example of what can happen if a mixed-use path actually gets used.
By following a zig-zaggy route which would not be obvious to the uninitiated, it is possible to (sort of) bike along South Camp Road by staying on side streets. Unfortunately, these are the same side streets referred to in the previous section which I would not want to ride on because of the effects of the resurfacing job.
The sidewalk on South Camp Road between Monument Road and Fallen Rock Road required some cuts into the hillside so that a level surface could be obtained. These cuts were made quite a few years ago and the "disturbed ground" has scarcely started to revegetate. Damaged ground in this neighborhood stays damaged for years because of the dry climate; and on the strongly slanted ground left by a cut for a trail or sidewalk, healing will probably not occur in my lifetime. This is not a big deal for bikeability; but it provides an example of the kind of environmental and viewshed spoilage that results whenever new walks or trails are carved into the landscape around here.
One of the most infamous of the various types of "Bike Lanes of Doom" can be seen in several places in the residential area north of downtown Grand Junction. In this scheme, bike lanes are drawn to guide cyclists directly into the path of any driver-side car doors being opened as the cyclist passes.
Cyclists foolish enough to use such lanes must carefully study the interior of each parked car they are about to pass to judge whether there is an occupant who may open the door and injure them as they pass. Cyclists have little chance of avoiding a collision if such an occupant cannot be seen (e.g., if the car has tinted glass windows).
To compound the problem, these lanes try to force cyclists to ride right alongside the parked cars—a position on the roadway where drivers about to open a door are less likely to see them approaching.
When road or trail planners try to lump bicyclists in with pedestrians instead of regarding them as what they really are—operators of vehicles—the result is bike traffic that doesn't work well with either motorized traffic or pedestrians.
My own personal experience from years of biking around suburban DuPage County (Illinois), which echoes that of John Forester, is that the safest and most effective approach to accommodating bikes is to
Provide roads with a wide lane, to be shared by motorized and non-motorized traffic—without an explicitly marked bike lane. This keeps the surface clean for bikes and encourages cyclists to ride correctly in traffic. 16' seems to be the recommended width. This is wide enough for cars to pass bikes without going into oncoming traffic, but not so wide that motorists would mistake the extra space for a second auto lane.
To eliminate interactions with pedestrians and minimize environmental damage, keep bicycles off of sidewalks and don't try to use off-road trails or mixed-use trails as a substitute for bikeable streets and roads.
Be mindful that many rough surfaces (e.g., concrete seams, large sharp stones) that would not be noticed by cars, pedestrians or fat-tire mountain bikers are not suitable for road bikes.
The problems with both on-road bike lanes and off-road bikeways is that
They lull novices into thinking that they don't need to learn to ride properly, and thus attract unsafe cyclists of the sort that safe cyclists (i.e., vehicular cyclists) and pedestrians would want to avoid.
They require special maintenance in addition to and different from normal street and road maintenance. Doing this correctly may involve prohibitive, ongoing costs.
In addition to environmental damage done by the construction of off-road bikeways, there is further damage when users wander off-trail. Off-road bikeways are particularly inappropriate in ecologically fragile areas like the cryptobiotic soil crusts in the Colorado National Monument and surrounding neighborhoods. Off-road bike trails should be limited to areas where the inevitable environmental damage is deemed to be alright, such as areas that have already been used for this purpose, already have an urbanized surface or that no one cares about.
When I look out my kitchen window and see a bike go by on Monument Road every few minutes, I wonder why the problems described here have persisted for so long with apparently no one complaining. Or maybe they are complaining but don't understand what they need to be asking for. As was mentioned above, most bicyclists seem to be novices and are likely to prefer "solutions" which allow them to indefinitely postpone learning how to ride correctly in traffic. And I have seen no evidence that most planners understand this subject matter. I think most of the good examples of bikeable roads, like the one I commuted to work on back in Illinois, are good simply because the pavement happened to be wide enough and there was no planner around to mess things up.
An electronic copy of this article can be found at thomasaburrows.com/trails