Reliable data from WIM systems is an important input for detailed studies of freight transportation, both road and rail. WIM data provides detailed information of the distribution of loading over different types of vehicles, over the road network and over time (hour of the day, day of the week, etc.). The studies of transportation trends are often the basis for long term decisions for freight policy, regulations for weight and dimension for commercial vehicles, and necessary investments required for road and rail infrastructure.

For example, longer and heavier vehicles, particularly on long distance corridors, could possibly contribute to the reliable and efficient movement of freight. By carrying greater payloads with fewer vehicles, they would be more competitive and fuel efficient. They would reduce congestion, which is a factor in fuel consumption, and would consume considerably less energy per unit of freight compared to the present fleet of vehicles. On the other hand, depending on the increase of weight and dimensions, there would be some negative effects on the infrastructure, particularly bridges, which may have to be upgraded. WIM data is an important input for the monitoring and assessment of the effects of these larger