A transportation investment that materially improves links between centres opens up previously unavailable options for new activities. Traditional cost-benefit analysis does not adequately take account of the value of this option; real options theory must be added to the analysis to evaluate the full benefits.
This paper uses a specific example, Auckland's Harbour Bridge, to motivate the importance of real options analysis. Using illustrative, multi-period models of the real options problem, it highlights how inclusion of real options factors may either increase or decrease the attractiveness of a proposed investment.
The models identify situations in which it is optimal to invest even where a standard benefit-cost ratio is less than one.