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Earlier, we asked rhetorically: “How would you like to drive a car on a road designed by an engineer who does not know how to drive and does not understand the rules of the road?” Those who plan and design bicycle facilities out of ignorance because they do not know how to operate a bicycle as a vehicle and thus create hazards are committing malpractice. To avoid the risk of malpractice, get training [1]. (As an interim measure, employ consultants with significant and relevant experience.)
Simply attending a good seminar on vehicular cycling is not enough, although it certainly helps. The planner or engineer must thoroughly understand why bicycles must be operated as vehicles in order to resist pressure from misinformed “bicycle advocates” for ill-advised facilities.
How can you tell if someone, including yourself, is a competent bicycle driver? A quick indicator is the ability to make a left turn in heavy traffic by “negotiating” with other drivers. (See photo “Left merge in traffic” in section 7 of this article.)
Every lane is a bike lane. This means those who plan or design bicycle facilities (including all non-freeway roads) must understand correct bicycle operation and design any facilities consistent with best practices of bicycle driving. The most comprehensive reference that should be familiar to transportation engineers is Bicycle Transportation, by John Forester, MIT Press, 1994. The Dilemmas of Bicycle Planning by Paul Schimek is a short article that should be read and understood by all bicycle planners.
“Bicycle Advocates” (people who promote the bicycle to advocate for other agendas, such as reducing car use) argue that roads are designed for automobiles, not bicycles. Actually, major roads are wider and stronger than they need be for automobiles because they are designed for trucks and buses. Since automobiles are lighter and smaller, truck roads are also quite suitable for cars. Bicycles are still smaller and lighter, so well-designed roads are certainly adequate for bikes.
Good bike route |
The picture at right shows a very good road for cycling. It has multiple lanes (5) that allow faster traffic to pass easily. The surface is in good condition and it is thoroughly salted in winter. Sewer drains are in the curb face, so they pose no hazard. The vehicle detectors at traffic lights are not marked but they work for any cyclist who knows where to stop. Most buses (but not the one pictured) carry bike racks, handy in case of bad weather or mechanical problems.
The cyclist in the photo was riding rather close to the curb. This position encourages passing drivers to squeeze past him. (The bus driver passed with adequate room as would be expected of a professional driver.) This author advises riding at least one foot further left (between the right tire track and center of lane) so drivers will realize that they must change lanes to pass. A cyclist who knows proper lane position will find this is an excellent route. The most valid complaint about the road (U.S. 42 near Cleveland, OH) is that it is not scenic.
This writer has no doubt that bicycle traffic was not considered when the road was built or recently re-paved. Indeed, the city engineer did not know, until this author told him, that the vehicle detectors work for bicycles. This is a good example of benign neglect — a well maintained road that is perfectly suited for bicycle transportation.
Wide Curb Lane [2]
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How might the road above be improved? Marking the vehicle detectors would help. If money were no object, another 2-3 feet of space in the right lane would be useful when traffic is heavy. But most of the time, traffic is not heavy so extra width would be wasteful. The greatest room for improvement is in education: Teaching cyclists, motorists and police that bicycles are vehicles that should be operated on the same road, by the same rules and with the same rights as other vehicles. Be sure to teach cyclists the “secret” of assertive lane position so they are safer and more comfortable on the road. And we must teach motorists that cyclists belong on the road, not the sidewalk.
Where space permits and traffic volumes justify the expense, a wide curb lane, as shown in the photo at right, benefits all users of the roads. Wide lanes are especially useful on 2-lane roads, where passing traffic may otherwise need to use the opposing-traffic lane. A wide lane helps motorists pass safely without delay. The extra space also helps cyclists feel more at home on the road. Wide curb lanes with smooth pavement and marking vehicle detectors (see below) should be the preferred means of “accommodating” bicycle traffic.
Wide lanes do not cause the safety hazards that separate facilities do. Where the curb lane is not wide enough for sharing between a bicycle and a motor vehicle, the cyclist must be expected and encouraged to use the full lane. Note that some cyclists are uncomfortable in a marginally-wide lane. They are reluctant to control such a lane yet it is not really wide enough for safe passing by wider vehicles.
In the photo, notice how the passing motorist is allowing generous clearance, yet not encroaching in the oncoming traffic lane. Also note the marking for an obstruction: a paint stripe that warns a cyclist away from a drain grate in the roadway. This is good practice consistent with guidelines in the Manual of Uniform Traffic Control Devices.
 Crack in road at drain grate seam — a serious fall hazard  Safer seam around drain grate. Cracks here are less likely to trap a wheel–but still must be fixed. |
Neglecting to fix road hazards exposes cyclists to danger. Public officials, highway engineers, road maintenance supervisors, and others concerned with building and maintaining roadways must understand that bicycles are balanced vehicles, often with hard, narrow tires and without a soft suspension. This makes cyclists highly vulnerable to road surface defects, such as bumps, holes, ridges and slots.
A bump produces an unpleasant jolt to the cyclist, can cause tire and/or rim damage, and may cause a crash if the cyclist loses control or swerves to avoid the bump. A hole produces a severe jolt. A deep one may cause a serious stopping fall, where the wheel is stopped and momentum carries the cyclist over handlebars. Ridges and slots nearly parallel to the line of travel can force the wheel to the side or prevent steering for balance, producing a diversion fall. Such a fall right in front of a passing vehicle can lead to a fatality.
The defect shown in the top photo at right is a deep slot at the joint between concrete of the roadway and a separate pour around a drain grate. Such defects are common on old concrete roads. This one may have been big enough to bring down a motorcycle. This author took a one-page list of road hazards with photos and explanations of the dangers involved to a city council meeting. By the next day, most of the defects had been temporarily patched.
The second photo at right shows a safer seam around a drain grate. This design avoids a slot in the direction of travel, making it less likely to trap a wheel and cause a fall. It is likely that this pentagonal shape was not chosen to accommodate bicycles. Still, it is a good idea that should be encouraged.
When a city is informed of defects such as discussed above, it must promptly fix the problem or be liable for any injuries caused. If not informed, officials may claim ignorance of the defect as a legal defense. It is better if the city welcomes the reporting of defects by making it easy via a web site report form or a telephone “hotline”. The best cities train their road maintenance supervisors and other officials so they recognize, understand and prevent these problems.
Marked detector loop |
Another example of not-so-benign neglect is vehicle detector loops that fail to detect bicycles. Some traffic officials deliberately ignore this problem because they do not want to encourage cyclists to be on the road. If vehicle detectors do not work for cyclists, the community loses some of its moral right to enforce traffic laws.
Sometimes vehicle detectors are adjusted improperly. The correct setting is not the minimum sensitivity that allows cars to be detected but rather the maximum sensitivity that does not cause spurious detection.
Communities can help cyclists and encourage respect for traffic law by
marking vehicle detector loops to show where to stop the bicycle in order to
trigger the circuit. NASA Glenn Research Center has done just that as part
of its effort for the Cyclist Friendly Communities Award. The photo at right
shows the traffic light by the Main Entrance. Note the small stencils over
the cut mark in the middle of both traffic lanes.
Shoulders are a popular place for touring cyclists riding in the country. Riding on the shoulder is appropriate for one who is cycling along a freeway. But on an urban road, the shoulder is generally NOT a safe place to ride. A shoulder cyclist is much more likely to suffer a collision with turning traffic because other drivers do not look for conflicting traffic off the roadway. In addition, the shoulder is likely to accumulate glass, gravel and other debris because passing traffic does not “sweep” it clean. In some states, operating a vehicle (including a bicycle) on the shoulder is technically illegal. This could cause a serious legal problem in the event of a crash. This is why knowledgeable cyclists avoid shoulders on urban roads.
Roadway and shoulder |
A small shoulder protects the edge of the pavement from being broken by keeping heavy wheels nearer the middle of the road where the road is better supported. A two foot shoulder is usually enough for this benefit.
In the photo at right, the travel lane is of marginal width to allow faster
traffic to pass a bicycle. The rest of the four feet of pavement in the
shoulder is wasted as far as cycling is concerned. If the fog line were
moved over as indicated by the dashed line, then the lane would be wide enough
to share with faster traffic. The remaining shoulder would still protect
the edge of the pavement.
Missouri R. bridge [3] |
In many U.S. states (particularly in the West) cyclists are permitted access to the shoulder of freeways in rural areas or where a reasonable alternate route is not available. In the photo at right (Highway 370 in MO, crossing Missouri River), the sign at far right tells cyclists to ride on the shoulder. The safety record for such access is quite good because, except at interchanges, there is no turning or crossing traffic to produce a hazard.
Even in cities, there are places where cyclists should be allowed freeway shoulder access to cross an obstruction, such as a river, by entering just before the bridge and exiting just after. In some cases, a freeway replaced an older route that once provided cyclist access. Moreover, a new, cyclist-prohibited freeway bridge is likely to be safer than the old, cyclist-permitted bridge. In some states, traffic laws must be corrected to permit freeway shoulder access.
Barricaded road |
Separate bicycle facilities are helpful in some situations: (1) As shortcuts or supplements to the road system to improve connectivity. Examples include connecting “suburban sprawl” neighborhoods, through parks or other places where cars are not welcome or to bypass a “traffic calming” barricade. The photo at right shows a cul-de-sac where a short path would be useful. (2) For touring cyclists in the country, where intersections are rare. (3) For recreational trails. (However be careful at road crossings.) (4) On long-narrow bridges where on-road access would otherwise not be feasible. (However, beware the approaches and avoid 2-way paths,)
In a very few places, bike lanes may actually improve conditions for cyclists. John Allen gives an example on the Charles River Road near Boston. However, generally a bike lane provides more illusion of safety than reality.
Shared Use Stencil |
In previous sections, we have shown that separate bicycle facilities often introduce hazards because they discourage following of the rules of the road. In addition, many of these facilities have dangerous design defects. A correctly designed, properly constructed and well maintained road is almost always the best bicycle facility.
Where bicycle facilities must be installed because of political
pressure from the uninformed consider
“stripeless” bike lanes instead of traditional bike lanes. These
consist of a bike stencil with arrow (sometimes called a “Sharrow” or “chevron”)
with no extra lane stripes. Be aware that a pair of bike lane
stripes is a traffic control device that tells people where to ride. As we
have seen in an earlier part of this series, bike lane stripes often tell
cyclists to ride in unsafe places.
We should never install traffic control devices that people must disobey to be safe. |
Making bike lanes stripeless avoids most of the problems of a marked bike lane, so long as the stencils are placed correctly. This is likely to be a problem on streets where parking is allowed. The symbols must never be placed closer than five feet from parked cars (this means at least thirteen feet from the curb, 14-15 feet is better). The best place for these stencils is near the middle of the traffic lane (between the wheel tracks) where they also last longer.
In most cases, the best bicycle facilities are well-designed ordinary roads. Most important of all, we must understand that facilities are never a substitute for education. We must fund education first.
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