Water interacts with several other sectors in the economy (hydroelectricity production, potable water, irrigation, industrial use). Additional hydropower may reduce
water availability for irrigation, or for industrial use, both with direct impacts to the
economy. Power production affects energy availability in other sectors (manufacture, transport, and so on). Thus, infrastructure services occur, both as outputs for
users, or as inputs among the raw materials for other infrastructure processes or
services elsewhere. This means that infrastructure services form part of a network.
An infrastructure system constitutes a complex grouping of equipment and persons,
having an objective, usually influenced by the neighbouring sub-systems, which
often, have multiple (usually conflicting) objectives, and a compromise between
these conflicting objectives has to be determined through trade-offs, etc. For maximum efficiency operation, the infrastructure system design should try to achieve the
overall objective in the best possible way.
6.1 Interactions Between Water and Other Sectors
Figure 6.1 illustrates the interactions between water and several other sectors in the
economy. As a start, surface water (water collected through lakes and rivers and
impounding reservoirs) is, after treatment, distributed for domestic and other uses. In
many countries, this distribution is usually done through gravity with minimum use
of pumping. If necessary, underground water is pumped to supplement the supply of
surface water.
However, pumping water from underground aquifers requires additional energy.
Thus, one strategy is to use surface water, as much as possible, before starting to use
ground water. While surface water may be stored in impounding reservoirs, notwithstanding evaporation, ground water will flow towards the sea whether it is being
harnessed or not. Therefore, a different strategy would advise pumping as much
ground water as possible, while saving the surface water for future use when the
aquifers run dry during dry weather and severe droughts.
Both strategies are possible. While the former tries to minimise energy use, it does
not guarantee availability of water during dry periods. The latter strategy tries
precisely to safeguard water availability, at a cost however: energy – which, in
some countries, may be expensive.
It is fitting to note here that water and energy interact on each other. Furthermore, in some locations it might be possible to generate hydroelectricity from water
and still be able to use the water for domestic, industrial and irrigation uses.
However, the interaction becomes even more extensive. Some farmers might still
be willing to pay for ground water (or desalinated water, as in the Canary islands) at
a higher price if they can still market their goods at a profit. The same reasoning
goes for industry.
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water availability for irrigation, or for industrial use, both with direct impacts to the
economy. Power production affects energy availability in other sectors (manufacture, transport, and so on). Thus, infrastructure services occur, both as outputs for
users, or as inputs among the raw materials for other infrastructure processes or
services elsewhere. This means that infrastructure services form part of a network.
An infrastructure system constitutes a complex grouping of equipment and persons,
having an objective, usually influenced by the neighbouring sub-systems, which
often, have multiple (usually conflicting) objectives, and a compromise between
these conflicting objectives has to be determined through trade-offs, etc. For maximum efficiency operation, the infrastructure system design should try to achieve the
overall objective in the best possible way.
6.1 Interactions Between Water and Other Sectors
Figure 6.1 illustrates the interactions between water and several other sectors in the
economy. As a start, surface water (water collected through lakes and rivers and
impounding reservoirs) is, after treatment, distributed for domestic and other uses. In
many countries, this distribution is usually done through gravity with minimum use
of pumping. If necessary, underground water is pumped to supplement the supply of
surface water.
However, pumping water from underground aquifers requires additional energy.
Thus, one strategy is to use surface water, as much as possible, before starting to use
ground water. While surface water may be stored in impounding reservoirs, notwithstanding evaporation, ground water will flow towards the sea whether it is being
harnessed or not. Therefore, a different strategy would advise pumping as much
ground water as possible, while saving the surface water for future use when the
aquifers run dry during dry weather and severe droughts.
Both strategies are possible. While the former tries to minimise energy use, it does
not guarantee availability of water during dry periods. The latter strategy tries
precisely to safeguard water availability, at a cost however: energy – which, in
some countries, may be expensive.
It is fitting to note here that water and energy interact on each other. Furthermore, in some locations it might be possible to generate hydroelectricity from water
and still be able to use the water for domestic, industrial and irrigation uses.
However, the interaction becomes even more extensive. Some farmers might still
be willing to pay for ground water (or desalinated water, as in the Canary islands) at
a higher price if they can still market their goods at a profit. The same reasoning
goes for industry.
160
6 Infrastructure as a System