Surface Transportation Efficiency Analysis Model
The Intermodal Surface Transportation Efficiency Act emphasized the assessment of multimodal alternatives and demand management strategies. This emphasis increased the need for planners to provide useful comparative information to decision makers with regard to proposed alternative transportation solutions. Benefit-cost analysis is a useful tool to compare the economic worth of alternatives through the evaluation of trade-offs between the mobility and safety benefits of transportation infrastructure projects and the cost of building, maintaining and operating these projects.
To facilitate detailed corridor and system-wide analysis, in the 1990's the FHWA developed the Surface Transportation Efficiency Analysis Model (STEAM). STEAM uses information developed through the travel demand modeling process to compute the net value of mobility and safety benefits attributable to regionally important transportation projects. The current version of this model, STEAM 2.02, is able to report mobility and safety benefits by user-defined districts and a new accessibility measure. The district-level reporting feature allows users to compare the impacts of transportation investments to resident trip-makers across aggregations of zones, which may represent neighborhoods, policy areas or political jurisdictions. The accessibility feature produces estimates of employment opportunities within a user-defined travel-time threshold of a district across a base and improvement scenario. Both an index and the percentage change are provided. The district reporting and accessibility features are useful new tools for gauging the social impacts of transportation investments.
STEAM is occasionally updated in response to user comments and requests. To facilitate this process, the Office of Planning and the Office of Asset Management have partnered to reinstate technical support for STEAM and established a Frequently Asked Questions forum. Users interested in STEAM who would like to receive email notification of product updates and other STEAM information should register for the STEAM User's Group.
Example Applications of STEAM