Static and Dynamic Capacity of Transport Infrastructure

The nominal capacity of most transport terminals and infrastructure is jointly defined by static and dynamic considerations:

Static capacity refers to the available land as bigger terminals or larger roads have conceptually more capacity. Static capacity cannot be easily changed without expanding the facility, which in areas of limited available land can be a complex proposition.
Dynamic capacity relates to infrastructure, labor and technology, which can be improved upon. For instance, a more efficient terminal operation strategy can increase its physical throughput and consequently its capacity without resorting to additional land. The dynamic capacity of a road system can also be improved with a better synchronization of traffic lights. The intensity and density of utilization is improved.

Improving dynamic capacity is a straightforward strategy to improve the efficiency and productivity of transport assets. However, at some point an optimal level dynamic capacity is achieved and nominal capacity can only be improved through additional static capacity. Optimal nominal capacity cannot be effectively achieved particularly since a specific transport facility or infrastructure is linked with others, so that capacity improvements must be synchronized. For instance, a port terminal operating near optimum nominal capacity is facing serious congestion issues in the form of queuing at the terminal's access points; ships may be queuing on the harbor side to access the terminal while trucks may be waiting at the gate to pick up or deliver containers.