17.8 Infrastructure Is Dynamic
17.8.1 Infrastructure Changes Status
Gradually, over time, infrastructure resources may alternate into different types,
among commercial, public, social, and mixed, or completely cease to be infrastructural. Both the resource set described by the three criteria and the subsets defined by
the typology depend on the circumstances and are often influenced by demand and
design. This evolution is depicted in Figs. 17.7 and 17.8.
Generally, a resource may be used to produce different types of output, depending
on demand and design, which may fluctuate or vary over time. If the downstream
demand decreases drastically to only a few uses (or users) and/or if high downstream
Use 2
Infrastructural
(general
purpose) input
Non
infrastructure
(special
purpose) input
Use 1
Use 1
…
Use 4
Use 3
Fig. 17.7 Evolution from infrastructure to non infrastructure
Public Goods
Private Goods
Fig. 17.8 Evolution form mixed infrastructure to commercial infrastructure
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17 Infrastructure as Public or Private Goods