photo courtesy City of Davis/U.C. Davis
Planning and designing for bicyclists involves different approaches for
different situations and purposes. For instance, an arterial street requires
a different approach than a residential street. Similarly, the approach
taken will vary with intention. A road that's part of a bike network or
that is used by many bicyclists may warrant more expensive measures than
one that is not.
Here are some commonly found situations and the approaches most often used.
1. Arterial streets are among the busiest streets in any
community. Experienced bicyclists often prefer arterials for their traffic
controls and directness. Other riders tend to avoid them, if possible, because
of the traffic.
The benefits for bicyclists include the aforementioned traffic controls
and directness. Arterials, for instance, may be the only streets that break
certain barriers like railroad yards, freeways, and rivers. But arterials
increasingly provide other benefits to cyclists as well. In suburban areas,
for example, many popular destinations--schools, worksites, shops--can only
be found along arterials. For destination-oriented bicyclists, therefore,
using arterials may be the only alternative.
Basic options for improving arterial streets include:
2. Collector streets are generally less busy and have
fewer lanes than arterial streets. Often, the lighter traffic makes for
a less stressful ride for many bicyclists and the less "hardcore"
riders tend to gravitate towards such streets.
While collector streets typically have less traffic than arterials, they
still -- by definition -- go somewhere. Unlike many residential streets,
they can reach destinations that are important to bicyclists. In some cases,
improving a collector that parallels a major arterial can provide a viable
alternative route for many bicyclists. Basic improvements for collector
streets include the same measures as for arterial streets but they may be
easier to implement:
3. Residential streets typically don't warrant special
provisions like bike lanes or wide curb lanes. However, given that they
harbor young bicyclists and casual family riders, there are some important
issues to consider. For example, several key types of residential street
bike/car crashes involve bicyclists and motorists being unable to see each
other in time to avoid a collision. In some intersections, for example,
their views are blocked by vegetation and fences.
In addition, residential streets that serve as commuter "rat runs"
can often benefit from traffic calming approaches. The purpose of traffic
calming is to slow and discourage through traffic in neighborhoods. Therefore,
residential streets may benefit from basic sight distance improvements and,
where warranted, traffic calming measures:
4. Rural roads and highways come in all sizes and shapes. Basically, a rural road or highway is a road that travels through an area with rural land uses (farmland, forests, deserts, etc.). Typically, it has no curbs, gutters, or adjacent sidewalks; it may have drainage ditches or swales, however. Some rural highways are trunk lines through highly-traveled corridors and, as a result, carry very high volumes of traffic. Others serve a few farms or serve as "back ways" between two destinations otherwise served by major highways.
Virtually all rural roads carry high speed traffic and this has serious implications for safe bicycling. Being hit by a high speed motor vehicle brings with it a high risk of death. Fortunately, such incidents are relatively rare--probably at least in part because rural bicycle traffic is low and the riders tend to be skilled--but they are a serious concern when planning for bicycling in either rural or newly developing areas.
On very low volume rural roads (e.g., those with AADTs under 1000), little improvement is generally needed for bicyclists. If such roads are popular bicycling routes, eliminating basic roadway hazards and, perhaps, installing route signs may be all that's needed. On higher volume rural roads -- particularly those with significant percentages of truck traffic -- providing adequate smoothly-paved shoulders is one of the most helpful improvements possible. Here are some of the most useful measures: