Finding and Exploring Use of Commodity-Specific Data Sources for Commodity Flow Modeling

Abstract

Commodity flow modeling studies rely on traditional data sources, such as the Commodity Flow Survey, the Freight Analysis Framework, Transearch, surveys, the U.S. census, county business patterns, and input–output models. The strengths and shortcomings of those data sources have been evaluated in the literature; the sources can be useful for modeling, but they do not necessarily support a supply chain approach or provide the level of detail or accuracy desired for modeling a particular commodity’s supply chain and flow on a city or state roadway network. This paper expands on the work of NCFRP Report 35: Implementing the Freight Transportation Data Architecture: Data Element Dictionary by finding existing data sources unique to specific commodities that identify key supply chain locations and industry relationships and that provide more detail about commodity quantity and movement to overcome the limitations of traditional freight data sources. The goal of the investigation was to find more data sets to use in commodity flow modeling. For each commodity, this paper describes data sources found, data attributes, and how those data were used to estimate flow from origins and destinations within supply chain links. The commodity-specific approach opens doors to sources of data not normally incorporated into transportation research.

Implementable Regional Truck Freight Planning Practices: Quick Ways to Get Started

“…The authors used waybill data coupled with the total number of vehicles produced at Texas auto assembly plants to determine the number of vehicles shipped by rail versus truck; then, other sources such as the location of dealerships, the location of railroad ramps for loading these autos, and population counts helped estimate origin–destination flows for automobiles. Other commodities have different data sources: to estimate timber flows, Kam et al defined origins as the trees harvested (available from the Forest Inventory Data Online database) and destinations the mills that process these trees (available from a Texas-specific source and the Primary Forest Products Network) ( 53 ). The authors then used a gravity model to estimate resultant truck flows.…”

“…For Practices 6 and 7, specialized travel demand modeling software or enhanced GIS is needed for analysis, although planners may have access to this software because of their other duties. Practices 5 and 7 were facilitated by the use of the StreetLight Insight data platform; an alternative is manual data collection (for Practice 5) and use of the gravity model, as suggested by Kam et al ( 53 ).…”

“…Implementation Example. To understand truck flows between timber forests and mills, Kam et al's approach was adapted to Brunswick County, VA, with a few changes (53). A key challenge is that although Virginia mill locations are available, exact locations of harvested timber forests are unknown.…”

“…Storage may affect costs: the aforementioned land cover data require roughly 9 MB for a county, and thus for a 15-county region, the size may exceed 100 MB with some increase in processing time. Use information from the Quick Response Freight Manual/Methods to estimate truck trips as needed for the regional model Scenario planning with respect to investments and land development (47) Use the regional model to examine how a mix of investments and different warehouse locations affect VMT and delay Scenario planning with respect to threats (48) and opportunities (49) Examine how a region's increase in shorter truck trips may be an opportunity to introduce electric trucks Obtaining freight data from public sources Use of innovative data sources or technologies to improve freight data (53) For various commodities, such as timber, identify origins and destinations from public sources to infer locations of high demand…”

“…Kam et al sought to advance this work by showing how to obtain commodity flows from various sources(53). For instance, most new motor vehicles are transported by rail (long haul) and then by truck (to dealerships).…”