Research Project

Baltimore Bicycle Project

Making Baltimore Bicycle Friendly Through a Public Health and Systems Engineering Analysis

In a world dominated by conversations about improving energy, environment, and health outcomes, tackling urban transportation issues is at the forefront of action items. A number of engineers, public health practitioners, and urban planners are promoting the redesign of our current urban transport infrastructure, which will require a fundamental change in commuting behavior. Transportation accounts for over 25,000TWh of annual energy consumption worldwide and greenhouse gas emissions from transportation are expected to grow by 80% before the year 2030 and already account for a quarter of global emissions.

In a world dominated by conversations about improving energy, environment, and health outcomes, tackling urban transportation issues is at the forefront of action items. A number of engineers, public health practitioners, and urban planners are promoting the redesign of our current urban transport infrastructure, which will require a fundamental change in commuting behavior. Transportation accounts for over 25,000TWh of annual energy consumption worldwide and greenhouse gas emissions from transportation are expected to grow by 80% before the year 2030 and already account for a quarter of global emissions.

An ever-present part of every proposal to improve urban infrastructure is to promote bicycling within urban centers. This is where public health professionals join the conversation, as increased physical activity is one of the best methods to stem the rise of non-communicable diseases. The Surgeon General’s report of 2006 indicates that at least a half hour of cycling daily reduces the risk of life-threatening diseases, thus increasing life expectancy. There are a number of health benefits including reduced risk of obesity, cardiovascular and other diseases, and these health benefits outweigh any health risks from bicycling (i.e., from airborne pollutants and road traffic).  The 2010 Global Burden of Disease Study highlights the large and continuing shift in global health away from communicable diseases and towards non-communicable diseases and injuries, which now account for more than two-thirds of all deaths. The study estimated that physical inactivity leads to 3.2 million premature deaths and ambient air pollution results in another 3.2 million deaths annually.

Bmore Bicycle Project MD mapOn the flip side, the road safety community within public health is not pushing bicycling because without adequate infrastructure and planning, bicycling is a high-risk activity for injuries. Road traffic injuries already kill 1.33 million people globally. Thus, promoting bicycling needs to be accompanied with planning and design for safe bicycling. The map on the right shows the incidence of bicycle deaths in the Maryland region.

Bicycling provides additional benefits such as an increase in quality of life, reduction in carbon emissions over other forms of transportation, and energy savings. Cost-benefit analyses show that economic benefits from an increase in bicycle use are more than four times the cost of investing in new urban infrastructure to benefit bicyclists.  In fact, the Baltimore city government states on its “Bike Benefits” website that a five mile bicycle commute saves 5lbs of carbon emissions, saves bikers $8 from not driving or $4 from not taking public transport, and riders can burn 250 calories.

However, commuters in urban centers often cite safety concerns as the primary reason for not riding bicycles (e.g. New York City Department of City Planning, 2007). Thus, any discussion about the promotion of bicycles within urban centers needs to include discussions about safety, including traffic on urban streets, accidents on bike trails, and other safety issues. An interdisciplinary systems approach with a focus on public health will help answer pertinent research questions about redesigning urban infrastructure to promote bicycles. The broad vision of this proposal stems from this idea; engineers and public health practitioners need to work together to make urban transport safe, sustainable, and equitable. The main research objectives are outlined in the next two paragraphs.

Research Objective: We are developing a novel computational framework for understanding the transport-health-sustainability nexus through a systems modeling approach. In this project, we will build the computational framework with a focus on developing a bicycle and transport flow equilibrium model for Baltimore, given the importance of the subject and the immediate policy interest.  The findings of this study will form the basis for multiple grant applications to expand the core computational framework as well as the allied areas of estimating health effects such as those due to injuries, physical activity, and air pollution, among others.

In order to build this bicycle-focused framework, we need certain specific forms of data. This includes traffic/bike volume in the current network, data from origin-destination surveys (e.g. to estimate latent demand from new bikers), and relative risks for injury. The last of these (relative risks) requires building a statistical model that uses Baltimore accident data and environmental covariates to build injury risk functions for every segment of the road network, which will be another major objective of this project. We will accomplish this using readily available data from the city of Baltimore supplemented with new data collected from this project.

Background Information and Preliminary Studies

In 2006, the Baltimore Departments of Transportation and Planning released a Master Plan as a guiding document for the promotion of cycling in the city (Bicycle Master Plan, 2006). In developing this plan, the city’s existing roads and trails were analyzed to draft a 500-mile bicycle network based on existing bicycle infrastructure, potential for improvement, among other criteria. Since the Master Plan was adopted in 2006, 42 bike lane miles have been added as of 2010. The challenge is to completely integrate this with the on-street network for robust service. Other issues to consider include bike parking, multimodal integration with public transport, and bike sharing. The Master Plan is currently up for its first review and addressing the important questions pertaining to bicycling are relevant today in Baltimore city.

Studying the flow of multiple vehicles with different characteristics in the same network has involved the use of simulation, multiobjective optimization, cellular automata, and agent-based models. Studies have also involved using optimization models to choose between two modes of travel along a network and mixed traffic flow with interference along traffic links. However, there have been no studies involving more realistic equilibrium models with bicycles and traffic flows over the same network with endogenous decisions to add/remove bicycle lanes, traffic routes, and public transport points, which this project aims to.

Research Design

Our equilibrium model will be calibrated using data on bicycle commuting and accidents in Baltimore. The first phase of the data collection will involve collection of data about traffic flow (bicycle and non-bicycle) across the city. Through our collaborator in the city planning office (Nate Evans), we will have access to bicycle volume data that has been collected in recent years for planning and implementing the Baltimore bicycling plan.  In order to meet the data needs of our optimization models, we will supplement the existing data with strategic measurements to fill-in the most important information gaps. For example, to find out individual paths of current bicycle trips through the road network, we may deploy a smartphone app among selected bicyclists in the biking community and generalize the data by mapping it to the population-level measurements already conducted by the city. Similarly, we may need to work with city traffic planners to place traffic counters at selected locations. Such work closely parallels the work being done by Dr. Kavi Bhalla in selected sites in China and Russia to measure road safety exposure. Similarly, his work in the GBD-2010 study estimates the incidence of road traffic injuries in information-poor settings using multiple poor quality data sources. The key philosophy of such work is to use existing data sources coupled with strategic new measurements to fill information-gaps and correct for biases.

The next phase will involve developing risk-exposure models, which will require geo-coded data on injuries and environmental characteristics. We expect to get such data via our partnership with the city. We will also work with the city hospitals to get supplemental data. In addition to accident data, we will need information on the built environment in locations where accidents happen. This will be done via a combination of Google-Earth, city planning maps, and site visits to collect more detailed information.

The project will answer relevant questions pertaining to Baltimore city’s six-year Bicycle Master Plan being developed in 2013, and propose new bicycle lanes, bicycle sharing initiatives, and changes in traffic flow. In particular, we will focus on the proposed Downtown Bicycle Network, which will begin construction in summer 2014. Assessments of a completed project on Guilford Avenue and proposed projects on Maryland and Mount Royal Avenues will also be done. Finally, using this information we hope to determine characteristics and modeling frameworks that can be applicable to general urban centers.

Dr. Sauleh Siddiqui has extensive experience in developing equilibrium problems to model diverse transportation and energy networks. His past work has heavily involved using large datasets to inform equilibrium models, including working with public health practitioners. He will lead the effort to develop the equilibrium model for traffic flow.

Dr Kavi Bhalla’s research at the JHSPH International Injury Research Unit focuses on assessing the safety impacts of transportation policy. His ongoing work includes measurement and evaluation of road safety interventions in Russia and China via observation studies of drunk driving, vehicle speed, and seatbelt use. From 2007-2012, he led a World Bank funded study to construct estimates of the incidence of road traffic injuries by triangulating from multiple incomplete data sources. He will lead the road safety analysis and data collection aspects of this project.

Dr. David Love is an active member of Baltimore’s bicycling community and has worked closely with Nate Evans as a member of Baltimore’s Transportation Safety Task Force. In 2011 – 2012, David lead a study on Baltimore motorist compliance with the 3-foot bicycle passing law, which has since been used as a policy and advocacy tool to increase the number and length of bicycle lanes in Baltimore. Most recently David has organized a design conversation on bicycle safety at the D:center in November 2012, and is an invited speaker at the Maryland State Bicycle Symposium on February 27, 2013.

Filed in:

Center for Systems Science and Engineering