Skip to main content

Study ‘shows more bicyclists on road means fewer collisions’

A study of cycle versus vehicle accidents carried out by the University of Colorado, Denver (CU Denver) has found that the chance of collision decreased with more cyclists. The risk of accident was relatively high at intersections with less than 200 cyclists per day. “Anywhere above this threshold is where we are seeing the largest safety benefits,” said co-author Wesley Marshall, PhD, PE, assistant professor of civil engineering at CU Denver’s College of Engineering and Applied Science. The reasons for
June 25, 2014 Read time: 2 mins
A study of cycle versus vehicle accidents carried out by the University of Colorado, Denver (CU Denver) has found that the chance of collision decreased with more cyclists. The risk of accident was relatively high at intersections with less than 200 cyclists per day.

“Anywhere above this threshold is where we are seeing the largest safety benefits,” said co-author Wesley Marshall, PhD, PE, assistant professor of civil engineering at CU Denver’s College of Engineering and Applied Science. The reasons for this remain unknown.

The study focused on Boulder, Colorado which has one of the highest rates of cycling in the country at about twelve percent of the population. This makes it one of the few US cities with enough bicycling to achieve the safety benefits already documented by researchers in Europe, according to Marshall.

The researchers wanted to create safety performance functions (SPFs) for bicycles in Boulder. These model the mathematical relationship between the frequency of crashes and major factors related to them. Yet while there are SPFs for vehicles, there are none for cycles. The authors created their SPF for Boulder by studying crashes at intersections throughout the city where more than two-thirds of collisions occur.  They compared the crash data to cycle count data.

“Fortunately, Boulder was one of the first cities to establish a bicycle counting program back in the late 90s,” Marshall said.

As cycling increases in cities across the U.S. each year, the results could have national implications. “In fact, we are beginning to find that cities with a high level of cycling are not just safer for cyclists but for all road users,” he said.  “Improving the streets to better accommodate bicycles may enhance safety for everyone.”

Related Content

  • Ramp metering delivers - again
    January 27, 2012
    Though still controversial, ramp metering, which has been around for nearly 50 years, continues to deliver substantial benefits, and generally for relatively small cost. Kansas City is a case in point. In March 2010, Kansas City Scout, a partnership between the Missouri and Kansas Departments of Transportation to provide ITS for the greater Kansas City Area, activated the first ramp metering system in the region. The project is located on an 8.85km (5.5 mile) section of Interstate 435 from Metcalf Avenue to
  • Idaho adds human dimension to winter savings
    September 23, 2014
    Idaho leverages the increased capability and reliability of its road weather sensor network to reduce costs and prevent accidents. Weather-related accidents can form a significant chunk of an authorities’ annual road casualty statistics. While authorities cannot control the weather, the technology exists to monitor the road conditions and react with warnings to motorists and the treatment of icy or snow-covered roads. However, with all capital expenditure now placed under the microscope of public scrutiny,
  • ITC provides agnostic traffic control software to Peachtree Corners
    September 26, 2023
    Intersection control specialist's 'Silicon Orchard' deployment is its first in the US
  • Study shows lifetime cost of EVs is comparable to conventional vehicles
    June 17, 2013
    Consumers who purchase an electric vehicle will find that costs to own the vehicle are competitive with conventional and hybrid vehicles, according to an analysis conducted by the US Electric Power Research Institute (EPRI). The study compares the Chevrolet Volt and Nissan Leaf with petrol-fueled cars that reflect average costs for different makes and models. Nissan lowered the price of the Leaf by about US$6,000 in January. It looks at several factors, including petrol and power prices, incentives, financi