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).

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, 2012 National Highway Traffic Safety Administration (NHTSA) data show that U.S. traffic fatalities increased (by 3.3 percent, from 32,497 to 33,561) for the first time since 2005.

Pedestrian fatalities increased (for the third straight year) by 6.4 percent, accounting for 14.1 percent of the total. Cyclist fatalities also increased (for the second year), by 6.5 percent, accounting for 2.2 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).

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.


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 75 percent of the nation’s $2.6 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. 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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