Photo by Nancy Pierce


Safety plays a large role in whether people choose to walk or bike. Many studies have observed that when the number of pedestrians and bicyclists increase, the rate of collisions between vehicles and pedestrians and bicyclists decrease. The reason is likely two-fold:

  1. An increased number of users leads to driver awareness and, thus, increased safety for pedestrians and bicyclists.
  2. Improving infrastructure and educating the public make walking and biking safer, leading to increased usage (Figure 1).
Figure 1. The safety and “safety in numbers” concepts.

Which of the two comes first or is stronger remains unclear, but in all places where the “safety in numbers” effect has been observed, significant investment in active-transportation infrastructure has also occurred.

Transportation trends indicate that Americans are driving less and walking and biking more, which should mean that travel is safer than ever. However, 2015 National Highway Traffic Safety Administration (NHTSA) data show that U.S. traffic fatalities increased (by 7.2 percent, from 32,744 to 35,092) for the second time since 2005.

Pedestrian fatalities increased (for the sixth straight year) by 9.5 percent, accounting for 15.2 percent of the total. Cyclist fatalities also increased by 12.2 percent, accounting for 2.3 percent of total fatalities. In addition to these alarming trends, the U.S. has a significantly higher risk of fatalities and injuries while walking and bicycling than in other countries (Figure 3).

Table 1. 2012 and 2011 NHTSA Data Showing Total Fatalities for Each Mode and Percentage of Change. | View Full Image →
Figure 2. Total traffic fatalities by mode (left) and percentage of growth in traffic fatalities by mode (right). Data are from the National Highway Traffic Safety Administration (2011, 2012). [1-4] | View Full Image →
Figure 3. Comparison of fatalities and injuries per 10 million (walking) and 100 million (cycling) kilometers traveled by country. * Cyclist injury rate for the United States is off the chart and is shown with a discontinuous bar. From “Walking and Cycling in Western Europe and the United States,” by J. Pucher, and &R. Buehler, 2012 TR News, 280, p. 37. | View Full Image →

Walking and biking by themselves are both extremely safe activities; most serious injuries and fatalities result from conflicts with motor vehicles. Improving safety can attract new users and increase the number of pedestrians and bicyclists. Treatments include simply adding sidewalks, installing visible signage to alert motorists of pedestrian crossings or adding island refuges across a multi-lane road, enabling trail users to focus on crossing one direction of traffic at a time. One study shows that adding protected bike lanes increases ridership and attracts new riders, getting people out of their cars and onto bikes.

Meanwhile, off-road trails provide a “gold standard” in terms of both objective and perceived safety by physically separating users from the road. Policy and transportation investment should reflect the fact that cars are not the only way to get around, by designing transportation networks that accommodate active transportation.

Trails provide a safe environment to walk and bike. | Pictured: Left - Austin, Tx., Right - Camden, Nj.


Addressing health concerns with preventative medicine is another major reason to provide active-transportation networks that, in turn, promote increased ridership. America has become more sedentary, in part because of the lack of a safe and convenient active-transportation system in many communities. Less than half (48 percent) of all adults meet the 2008 Physical Activity Guidelines. This lack of physical activity, both for recreation and purposeful trips, has resulted in an increase in heart disease, obesity and many other conditions to unprecedented levels in Americans. Medical care costs for people with chronic diseases account for more than 86 percent of the nation’s $2.7 trillion medical care costs each year.

Physical activity is truly the best medicine [5-14]; it—

The CDC’s Guide to Community Prevention section, “Creation of or Enhanced Access to Places for Physical Activity Combined with Informational Outreach Activities,” gave trails the highest marks with a Strong Evidence of Effectiveness rating. Moreover, the CDC's Community Preventative Services Task Force found sufficient evidence that combining a pedestrian/bicycle built environment intervention with a land use and environmental design intervention was effective in increasing physical activity and recommends it as a strategy. Trails can be a valuable primary prevention tool by providing a safe and cost-effective way for individuals to acquire physical activity outdoors.

  1. National Highway Traffic Safety Administration. (2013). 2011 PEDESTRIANS Traffic Safety Fact Sheet. View source →
  2. National Highway Traffic Safety Administration. (2013). 2011 BICYCLISTS AND OTHER CYCLISTS Traffic Safety Fact Sheet. View source →
  3. National Highway Traffic Safety Administration. (2014). 2012 PEDESTRIANS Traffic Safety Fact Sheet. View source →
  4. National Highway Traffic Safety Administration. (2014). 2012 BICYCLISTS AND OTHER CYCLISTS Traffic Safety Fact Sheet. View source →
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