Longer Combination Vehicles on Exclusive Truck Lanes: Interstate 90 Corridor Case Study
2.0 Research Approach
With the corridor identified, the study team engaged in three research-oriented activities to build the analysis methodology. Those activities included:
- Development of an analytical framework to measure the potential utilization and impacts of the ETL corridor;
- Data collection acquisition and testing of the framework; and
- Outreach to relevant stakeholders to validate the approach and to deepen the understanding of industry reaction to the ETL corridor scenario, including the potential for LCV deployment.
The following paragraphs provide a brief overview of the research approach. Subsequent sections provide additional detail on the discovery, analysis, and findings.
2.1 Analytical Framework
The analytical framework for this study was developed to estimate the potential divertible freight trips of semi-trailer trucks and rail shipments that would migrate to LCVs. The framework also establishes ranges of potential utilization based on observed and modeled data.
Building off recent truck size and weight studies by the States of Minnesota and Wisconsin, the analytical framework was also developed to estimate impacts of the change in truck or rail travel on a series of performance metrics, including safety, emissions, highway maintenance, and logistics costs.
2.2 Data Collection and Testing
Data was collected on freight movements, highway infrastructure, infrastructure costs, toll rates, and other key elements necessary for the estimates of the study. Data sets included:
- Vehicle classification counts from the study area states (i.e., Indiana, Ohio, Pennsylvania, New York); and from Federal sources, such as Vehicle Travel Information System (VTRIS) and the Comprehensive Truck Size and Weight Study of the U.S. Department of Transportation (DOT);
- The FHWA’s Highway Economic Requirements System (HERS), Highway Performance Monitoring System (HPMS) data, and Freight Analysis Framework 2 (FAF2) data;
- Toll rate information by vehicle classification; and
- Attributes of physical facilities and characteristics of proposed or operating truck lanes.
The testing phase utilized several innovative applications, including the use of the FAF2 data assigned to a highway network. This network assignment allowed the study team to conduct ‘select link analysis’ queries to identify a population of trucks by highway segment. This detail – including origin, destination, payload, and commodity – enabled the study team to test observations.
The outreach activities of this study included two industry roundtable events and a series of interviews.
- Trucking Industry Roundtable. In January of 2008, the FHWA convened a group of industry stakeholders to provide this effort with private-sector input, and to help develop the best scenario for testing. This group, comprised of trucking, shipping, rail, and advocacy organizations, met in Tyson’s Corner, Virginia, to provide input to the study team. That event helped the study team narrow its focus to the I-90 corridor, and to frame some of the issues and parameters of the study.
- Trucking Safety Roundtable. In May of 2008, the FHWA organized another roundtable event – this time to discuss the safety dimensions of exclusive truck lanes and LCVs. Attendees included representatives of national safety organizations, Federal agencies, and the trucking industry. This event reiterated public concerns about larger trucks, and provided the study with direction on the physical and operational characteristics of the system.
- Industry Interviews. Finally, the study conducted a series of interviews with likely LCV carriers and shippers to further ascertain the potential utilization of the corridor and willingness to pay a toll in exchange for LCV-afforded productivity gains.
This report integrates the findings of these outreach activities into the analytical approach of the study.