Background and Trends
Bicycling is an integral part of our country's transportation system. Yet, with the increasing popularity of bicycling over the past several decades, the risks to bicyclists are still evident. Engineers and planners increasingly recognize the needs of bicyclists of varying abilities. This has led to an increasing focus on the development of bicycle guidelines, particularly with the aim of improving bicycle safety. The NACTO Urban Bikeway Design Guide and the AASHTO Guide for the Development of Bicycle Facilities (2012) are examples of such efforts. The Bicycle Safety Guide and Countermeasure Selection System (BIKESAFE) is another resource that can help transportation professionals improve conditions for bicyclists.
As the built environment evolves to better support multiple transportation modes, consideration should be given to how bicyclists can be accommodated. Creating a safer bicycling environment involves more than striping a bike lane or building a separated path. Creating a truly safe and viable bicycling network involves communities and stakeholders that comprise the four E's—engineering, education, enforcement and emergency services—working together to address all aspects of safety, from signage and mapping that alerts riders to the level of skill necessary on a facility to the details of the design.
While some U.S. cities are making great strides in promoting bicycling by installing innovative facilities or introducing bikesharing systems, there is still a lack of adequate bicycle facilities in many communities. Improving conditions for bicyclists will often require a retrofit of existing roads, streets, and trails. By providing facilities for bicyclists, cities and transportation agencies can improve safety for all road users (e.g., by providing paved shoulders, reducing speeds, access management, etc.).
The nature of the built environment is important not only for walking but also for bicycling. Features that foster bicycling include:
- Having destinations close to each other
- Choosing sites for schools, parks, and public spaces appropriately
- Allowing mixed-use developments
- Having sufficient densities to support transit
- Creating commercial districts that people can access by bicycle (or foot and wheelchair)
- Providing adequate, visible, and secure parking
According to a national survey, the average bicycling trip is 3.9 miles and about 58 percent of bicycling trips are less than two miles.1 When residents are separated from sites such as parks, offices, and stores, there will be fewer bicycling trips because destinations are not close enough for bicycling. While numerous studies have shown that bicycling levels are higher in dense, mixed-use areas where households are close to destinations like offices and stores,2 single-use, low-density residential land-use patterns can discourage bicycling, especially if the connecting roads to other destinations have high speeds and traffic volumes and inadequate bicycle facilities. Bicyclists in suburban areas are more likely to feel their personal safety is compromised compared to those in urban or rural areas.1
More communities are considering the connection between land use planning and transportation planning. Integrating land use and transportation planning allows new developments to implement these strategies from the onset.
In established communities, many of these goals can be met with infill development that increases density and improves community viability. In addition, providing appropriate bicycling facilities between desirable destinations will result in more bicycle trips.2 The facility may be as simple as a normal-width shared lane on a street with low traffic volumes and slow motor vehicle speeds. More cities in the U.S. are designating low-volume neighborhood streets with traffic calming measures like bicycle boulevards. These routes give priority to bicycles over motor vehicles and are especially attractive to less experienced cyclists.3
Bicycles are vehicles and are able to travel on a wide variety of roadway types. It should be assumed that bicyclists will want to ride, and plans should be made to accommodate them on new infrastructure or renovation projects. The Federal Highway Administration (FHWA) has encouraged routine accommodation for bicyclists (and pedestrians) for many years, and the concept has been embraced by many state and local departments of transportation (DOTs).4
Bicycles can be used to commute, to run errands, to visit neighbors, to shop at local stores, to transport children, to get exercise, or for recreation. The provision of safe facilities is very important, but the design of those facilities affects their attractiveness and comfort for bicyclists of all skill levels. Bicycling can be encouraged by reallocating space on existing streets that bicyclists are known to frequent. This could involve removing parking, narrowing travel lanes to slow motor vehicle speeds, and using the space added from lane narrowing to accommodate bike lanes, paved shoulders, or wide curb lanes.
Communities interested in promoting bicycling need to know where bicyclists ride, as well as where they want to ride. Once desired corridors are identified, an inventory can help locate deficiencies. Besides facility improvements, it is also beneficial to provide pleasant bicycling conditionsâ€”therefore both the built and natural environments are important components of an attractive bicycling environment. The environment may also be improved in part through landscape design elements, which can improve aesthetics, offer a sense of visual narrowing, and perhaps reduce traffic speeds.
Bicyclists also want to ride in an environment where they feel safe from motor vehicle traffic, crime, and other concerns that can affect personal security. In some cases, traffic safety problems have been addressed by analyzing police crash reports and improvements made based on the frequency and severity of crashes. However, planners, engineers, and other practitioners are engaging in problem-identification methods such as interactive public workshops, surveying bicyclists and drivers, meeting with police, and conducting bicycle road safety audits to identify safety problems in an area before crashes occur. This may help proactively identify locations for bicycle safety improvements and will involve residents in the process of improving safety and mobility in their own communities. Lighting and other safety and security measures should be considered in certain locations. Similarly, improved enforcement may address some of the issues identified.
In addition to BIKESAFE, which provides countermeasures for all of these issues, FHWA developed its Bicycle Road Safety Audit (RSA) Guidelines and Prompt Lists in 2012. The guidelines present an overview of basic principles of the safety of bicyclists and potential issues affecting bicyclists. The prompt lists describe safety considerations when conducting a bicyclist-specific RSA.
A bicycle can be ridden on almost any kind of roadway, yet certain traffic conditions create a sense of discomfort, even for a skilled bicyclist. A high volume of traffic is one of those conditions and can affect a bicyclist’s feeling of safety and comfort, especially when bicyclists are required to share space with automobiles.
Motor vehicle traffic speed is equally critical to the safety and comfort of bicyclists. Not only are higher speed roadways less comfortable for bicyclists, but when a crash does occur, these higher speeds significantly increase the chance of serious injury and death. Additionally, at higher speeds, motorists are less likely to stop in time to avoid a crash due to driver response times and braking distance. Through the use of speed reduction measures, motor vehicle stopping distance could be reduced from approximately 250 feet to 150 feet, given a speed reduction from 35 mi/h to 25 mi/h, respectively.5
Many streets are designed to accommodate higher motor vehicle traffic volumes and speeds in an attempt to better handle peak hour congestion. Most bicyclists will try to avoid these streets if possible, but issues arise where bicycling corridors overlap high-volume and high-speed roadways. As motor vehicle traffic volume and speeds increase, providing space for bicyclists through bike lanes or separated facilities like “cycle tracks” becomes more important. Sometimes a separated bicycle path may be necessary to provide a more comfortable option for less experience cyclists. The figure to the right demonstrates the relationship between speed, volume, and bicycle facility type. For more specific guidance on facility selection, see the Resources section and any applicable agency design standards.
New streets can also be configured for lower design speeds without a great sacrifice in capacity. Speed reductions can increase bicycling safety and comfort considerably. On slow speed city streets and lightly traveled roadways, bicyclists may safely operate in the normal traffic lanes. However, on heavily traveled streets, bicyclists need space to operate and motorists need room to overtake a bicyclist. Space can be provided through the use of bike lanes, paved shoulders, or wide curb lanes, and these facilities can often be created by narrowing traffic lanes through restriping (e.g., reducing traffic lanes from 12 feet to 10 or 11 feet), as appropriate. Such changes may be able to be made within existing local and state design standards or may require exceptions, depending upon the conditions. More details are provided in the Countermeasures section.
The concept of Complete Streets builds on the previous concept of routine accommodation for bicyclists and pedestrians. Complete Streets are designed to create safe and convenient access for all users, including bicyclists, pedestrians, motorists, and transit riders of all ages and abilities. Consideration of all users should begin in the design process, instead of curb to curb, designers should think more completely about building face to building face. In addition to improving safety for current bicyclists and pedestrians, completing the streets should encourage more people to bike and walk.
Some jurisdictions choose to adopt standalone policies, while others choose to incorporate Complete Streets into existing planning documents. According to the National Complete Streets Coalition, in 2013, 466 local and regional jurisdictions, 27 states, the Commonwealth of Puerto Rico, and the District of Columbia have adopted Complete Streets policies or made a written commitment to do so.6 The Alliance for Walking and Biking has released the third edition of its Complete Streets guide, which offers information about policies, project implementation, and guidance for Complete Streets campaigns and communication.7
In addition to adopting policies, jurisdictions are ensuring implementation by creating Complete Streets design guidelines or revising existing streetscape guidelines to reflect their Complete Streets policy. At the state-level, the North Carolina Department of Transportation (NCDOT) developed its own planning and design guidelines and is offering two-day trainings to state and local engineers and planners across the state.8 At the local-level, the City of Chicago recently released design guidelines that will help implement the city’s 2006 Complete Streets policy and join the city’s bicycle and pedestrian planning efforts.9
Bicycling and transit are complementary. Connections to transit stops are important for the usefulness of a transit network, so users must be able to access transit stops not just on foot or by car, but also by bicycle. Transportation officials and advocates are paying increasing attention to the “last mile” by conducting audits and improving routes that lead to transit stations so they are safer and more appealing for bicyclists and pedestrians. Transit facilities that support bicycle and pedestrian access are important in creating a comprehensive transportation network.
Many public transportation agencies are providing bicycle racks on buses, enabling what might be a long bicycling trip to be shortened by using transit for part of the journey. In 2001, only 32 percent of buses in the U.S. had exterior racks for bicycles, but that figure rose to 72 percent by 2010.10 Bike parking is another key aspect for integrating bicycling with public transit. Cyclists have a strong preference for secure, sheltered parking that deters theft and protects bicycles from inclement weather.11 Carrying a bicycle onto a train or light rail vehicle is also becoming more common. For example, Caltrain in the San Francisco area has become very accessible for bicyclists by ensuring that every train has two bike cars that can accommodate 48-80 bicycles.12 Such access is yet another way to combine bicycling with another mode of transportation.
Friendly and comfortable transit stops are also a plus. Some consideration needs to be given to the on-street riding conditions around transit stops frequented by bicyclists making use of bus racks and bicycle parking. Feeling unsafe on the bicycle for even a short distance may discourage use of a combined bike-transit trip. For some municipalities, the presence of transit stations or stops is considered in demand models and/or project prioritization criteria. For example, Chicago’s Bicycle 2015 Plan considers transit stations as priority destinations for establishing bikeways and the plan includes a transit chapter with multiple performance measures related to increasing bike-transit trips. In Boulder, Colorado, the Bicycle System Plan requires that all transit centers and park and rides be serviced by primary and secondary bicycle corridors.
The health benefits of regular physical activity include reduced risk of chronic diseases, lower health care costs, and improved quality of life for people of all ages. The Centers for Disease Control and Prevention (CDC) recommends that adults ages 18 and up get 150 minutes of moderate activity or 75 minutes of vigorous activity per week to reduce the risk of chronic health conditions such as heart disease, Type-II diabetes, and some cancers. Currently, less than 10 percent of Americans reach the recommended amount. Health benefits of bicycling also come from improved social capital and reduced car use, including improved air quality, reduced noise pollution, and reduced greenhouse gas emissions.13 As the focus shifts from the treatment to the prevention of disease, public health professionals are partnering with urban planners and engineers to create bicycle-friendly communities that promote greater amounts of bicycling for leisure and for transportation.
Transportation cycling provides an opportunity for people to incorporate physical activity into daily life. Since cycling is accessible, affordable, and achievable by people of all ages, the challenge is to find ways to increase cycling in the population.13 Bicycle commuting has been shown to be an activity that meets recommended intensity levels and to be related to lower rates of obesity.14 Since nearly half of all daily trips made in the U.S. are three miles or less in length, the potential to switch trips from driving to bicycling is significant.14