Will changes in technology, policy or demand affect how the needs of tomorrow are met?
In many situations, the public sector must maintain a degree of flexibility to meet likely, or even unanticipated, evolution in infrastructure and service needs. Some partnership models are ill-suited to infrastructure systems that are likely to be recast over time to meet changing demand, particularly growth. If the public sector is not certain about the performance requirements underlying the partnership, then it will be difficult to achieve a fair contract price and to ensure that the infrastructure will continue to meet future demands.
Uncertainties might result from latent defects (flaws in the existing infrastructure that are not apparent until work begins), policy changes (implying a change in service requirements), demand risks (resulting from the introduction of user choice, for example), changes in public needs or rapid changes in technology. For projects that are especially vulnerable to these uncertainties, partnership models with increased flexibility and shorter contract periods can improve the likelihood of achieving infrastructure objectives.
How infrastructure needs are defined and met will change with advances in technology. New technology can make the unexpected and, at times, the seemingly impossible, possible. One example is the tunnel constructed to add the missing link to the A86 ring road around Greater Paris. A problem that had perplexed urban planners for more than 30 years was resolved thanks to rapid advances in technology, such as made-to-measure tunnel boring machines that could simultaneously drill, excavate and provide structural finishing.