Spatial coverage index for assessing national and regional transportation infrastructures

Development of the transportation planning process at various decision levels (strategic, tactical, and operational) has strengthened the need for specific indicators as the basis for decision-making. Within the decision-making structure, however, the most popular indicators for national and regional analysis (i.e., extension, density) are still based on a legacy of limited technology and data availability. Growth in spatial of technologies, such as GIS, and reliable georeferenced databases can support new approaches to analyzing those indicators that shed light on infrastructure and service availability frameworks. This paper synthesizes and expands the former Roadway Coverage Index (RCI) as a Transport Spatial Coverage Index (TSCI) based on the concepts and characteristics of specific indicators, using the currently available tools, and taking into account network spatial behavior. Based on its structure, the TSCI is more robust and reliable than other approaches (network extension, spatial density, and population density), and it also has sound and convenient features for planners and decision makers towards national and regional infrastructure planning.