The Market Access Module draws on a rich geographic database of information on the spatial pattern of population and business, applying "new economic geography" research to estimate the productivity gain from transportation changes that have impact beyond merely savings in traveler time and cost.  It specifically calculates the value of enhancing transportation system connecticity (between road networks and inter-modal rail, air and marine ports as well as international gateways) and expanding scale of market access (for labor markets, suppliers and customer delivery markets).  It calculates the effect that these changes can have on business productivity, location pattern adjustments and economic growth over time.

Use of this module is not required, but is useful if a project, program or future scenario is expected to lead to changes in local market access or network connectivity (beyond just enabling direct cost savings for travelers).  Users provide straightforward input data using sketch planning methods, transportation models or GIS systems. The module calculates impacts on expansion of labor markets and delivery markets for various sectors of the economy, and it applies econometric equations to identify resulting impacts on industry agglomeration, supply chain dispersion and market scale economies -- which will directly affect productivity benefits (in the Benefit-Cost module) and economic growth (in the Economic Adjustment module).  Care is taken to avoid double counting of benefits, so that only scale economies (which are beyond travel time and cost savings) are counted.

Results appear in three places.  Market access reports provide calculations of the proportional increase in market size and intermodal connectivity resulting from implementing a “Project” scenario instead of the “Base” Scenario. For road travel, the access benefit is measured as the percentage expansion of population coverage for labor and truck delivery markets. For rail, air and water dependent travel, the access benefit is measured as the percent improvement in road access time to intermodal terminals and frequency/breadth of travel available at those terminals. Benefits by sector of the economy are shown by region and mode for the future target year. (See example shown below.)  This information drives changes in the calculation of economic productivity that is shown in a later Benefit-Cost report, and subsequent economic growth that is shown in a later Total Economic Impact report.