For decades, highway engineers have had a universally accepted means of measuring the effectiveness of new or improved roads, and that metric, known as “level of service,” has also profoundly reshaped the way our cities and towns look and function.
Now, as growing numbers of urban and suburban residents opt for other forms of transportation, including their own two feet, as a primary means of getting around, planners who are faced with making choices about reshaping streets and roads to safely accommodate pedestrians and bikes have been making up measurements of effectiveness as they go along. The risk here is that the absence of a universally accepted standard will lead local governments to spend more money than necessary on improvements that have little real benefit.
New research conducted at the University of Illinois at Chicago’s Urban Transportation Center takes a first step toward developing such a standard, and it too could in the long run profoundly reshape the way our cities and towns look and function.
The research was published in a paper, “Development of an Analytical Framework to Rank Pedestrian and Cyclist Projects,” by Nadereh Moini, a research professor (who has since left UIC). P.S. Sriraj, who worked with Moini on the project, explains that the project was undertaken in response to changing attitudes about transportation in America.
Bicycles and walking have historically been perceived as inferior modes of transportation in the United States, Sriraj notes. In other countries, however, “these modes are infused into the fabric of the day-to-day lifestyle, and they are seen as important and essential pieces of the transportation infrastructure.” Land use patterns in the United States have also made walking and bicycling difficult.
But attitudes among younger Americans are forcing a rethinking of the subject. “All the studies point to millennials being aware of their environment and surroundings,” Sriraj said. “They’re putting off getting driver’s licenses, getting cars later in life, and settling in denser areas and choosing to use bikes to get around.” Add to this cohort aging baby boomers who are also opting to downsize their lifestyles and suddenly designing U.S. urban transportation networks to accommodate pedestrians and bikes becomes important again.
And this is where Moini’s research comes in. Since the funds available for pedestrian and bicycle infrastructure are scarce, developing a uniform way to measure their effectiveness will help local governments determine how best to use those scarce funds. Moini’s method examines seven factors:
Safety — frequency and severity of crashes involving pedestrians and cyclists
Safety effectiveness — reduction in the frequency and severity of crashes
Mobility — the contribution the improvement makes to overall bike/pedestrian access
Demand — likelihood that pedestrians and bicyclists will use the facility
Equity — the degree to which a project improves mobility for less privileged areas
Cost — capital, operating and maintenance costs over the lifespan of the improvement
Qualitative factors — intangible factors derived from opinions of local experts
A value is calculated for each factor; the safety effectiveness value is scaled to ensure that crash reduction rates are measured proportionally to improvement costs. Then the values are weighted, with the safety and safety effectiveness values given the greatest weight, and all are summed to produce an overall score.
Moini applied this method to 10 cities in Cook County where data showed the greatest need for pedestrian and cyclist infrastructure improvements. Overall scores were given to 29 pedestrian projects ranging from crosswalks to raised medians, curb bumpouts and pedestrian signals, and 17 cyclist projects, all of which either created bike lanes or installed special signals for cyclists. The projects were then ranked according to their overall score.
“Many state and municipal governments have methods for measuring project effectiveness, but there’s a question of whether they are uniform across the board and take into account the wide range of variables involved,” says Sriraj. “Even this model needs to be made more rigorous, but we have the beginning of something that’s uniform and can be applied consistently across jurisdictional boundaries. That’s especially important when you’re making tradeoffs.” In its case study, the research paper used the scores to determine how to allocate $800,000 in Congestion Mitigation and Air Quality (CMAQ) funds the Chicago Metropolitan Agency for Planning has available to distribute to pedestrian improvements ($500,000 total) and cyclist improvements ($300,000 total), and not all of the projects made the cut for funding.
“We feel very comfortable with the results we have received, but we have not taken them back to the communities to see if they are consistent with their views or with the decisions that they have made,” Sriraj says.
That reality check is one of the next steps for testing the metric; others involve getting data for other cities and inviting transportation professionals beyond Chicago to give feedback on the robustness of the model and ways it can be improved.
The Works is made possible with the support of the Surdna Foundation.
Next City contributor Sandy Smith is an associate editor at Philadelphia magazine. Over the years, his work has appeared in Hidden City Philadelphia, the Philadelphia Inquirer and other local and regional publications. His interest in cities stretches back to his youth in Kansas City, and his career in journalism and media relations extends back that far as well.