50
billion in 2006, to USD 772 billion in 2015, to USD 1,038 billion in 2025 (Ashley
and Cashman 2006 ). And the projected expenditure on water infrastructure as
percentage of GDP will increase too, from 0.75 % in 2015 to more than 1 % in
2025. These values do not include the major water engineering projects that are
either planned or under construction. For example, the construction of 3,700 future
hydropower dams may require an investment of about USD 2 trillion, excluding
operation costs as well as the costs caused by social and environmental damages
(Zarfl et al. 2015 ). A primary challenge in designing and operating major water
infrastructure projects will be to balance the economic benefi ts while preventing
social costs and the loss of natural ecosystem services.
In this chapter, we provide a comprehensive albeit in no case complete inventory
of future major engineering projects, so-called megaprojects, that are either planned
or under construction in freshwater systems worldwide. We focus on very large
dams, major interbasin water-transfer and navigation projects, as well as on largescale restoration schemes. The main goal is to raise awareness about the dimension
of and the challenges associated with future megaprojects. We discuss opportunities
to mitigate the consequences of megaprojects based on the lessons learnt from projects in other infrastructure sectors.
4.2 Major Engineering Projects in the Water Sector
Major engineering projects are large-scale and complex projects that typically cost
much more than USD 1 billion, require years to decades to be developed and constructed, affect large areas – very often across political and geographical boundaries,
involve many public and private stakeholders, induce transformational processes, and
may impact millions of people (Flyvbjerg 2014 ). In the water sector, such megaprojects
encompass interbasin water-transfer projects, large-scale wetland drainage and irrigation schemes, navigation canals, drinking water facilities and sewage treatment plants
for large cities, large dams, fl ood control and coastal protection measures, and major
restoration schemes (Table 4.2 ). Furthermore, many small engineering projects may
have cumulative effects that are similar to the effects caused by individual
megaprojects.
The monetary scale of the investment is often inversely correlated with the
potential for future adaptation and modifi cation. Indeed, the lifespan of major water
infrastructure projects is a century, and more, therefore new ideas and creativity
now get “fi xed”. It means that the decisions we make now will heavily constrain the
options we will have later.
4.2.1 Interbasin Water-Transfer Projects
Interbasin transfer projects (IBTs) are considered as an approved engineering solution meeting the accelerating demands for water to secure food production, support
economic development and reduce poverty. To compensate for the increasingly
K. Tockner et al.
billion in 2006, to USD 772 billion in 2015, to USD 1,038 billion in 2025 (Ashley
and Cashman 2006 ). And the projected expenditure on water infrastructure as
percentage of GDP will increase too, from 0.75 % in 2015 to more than 1 % in
2025. These values do not include the major water engineering projects that are
either planned or under construction. For example, the construction of 3,700 future
hydropower dams may require an investment of about USD 2 trillion, excluding
operation costs as well as the costs caused by social and environmental damages
(Zarfl et al. 2015 ). A primary challenge in designing and operating major water
infrastructure projects will be to balance the economic benefi ts while preventing
social costs and the loss of natural ecosystem services.
In this chapter, we provide a comprehensive albeit in no case complete inventory
of future major engineering projects, so-called megaprojects, that are either planned
or under construction in freshwater systems worldwide. We focus on very large
dams, major interbasin water-transfer and navigation projects, as well as on largescale restoration schemes. The main goal is to raise awareness about the dimension
of and the challenges associated with future megaprojects. We discuss opportunities
to mitigate the consequences of megaprojects based on the lessons learnt from projects in other infrastructure sectors.
4.2 Major Engineering Projects in the Water Sector
Major engineering projects are large-scale and complex projects that typically cost
much more than USD 1 billion, require years to decades to be developed and constructed, affect large areas – very often across political and geographical boundaries,
involve many public and private stakeholders, induce transformational processes, and
may impact millions of people (Flyvbjerg 2014 ). In the water sector, such megaprojects
encompass interbasin water-transfer projects, large-scale wetland drainage and irrigation schemes, navigation canals, drinking water facilities and sewage treatment plants
for large cities, large dams, fl ood control and coastal protection measures, and major
restoration schemes (Table 4.2 ). Furthermore, many small engineering projects may
have cumulative effects that are similar to the effects caused by individual
megaprojects.
The monetary scale of the investment is often inversely correlated with the
potential for future adaptation and modifi cation. Indeed, the lifespan of major water
infrastructure projects is a century, and more, therefore new ideas and creativity
now get “fi xed”. It means that the decisions we make now will heavily constrain the
options we will have later.
4.2.1 Interbasin Water-Transfer Projects
Interbasin transfer projects (IBTs) are considered as an approved engineering solution meeting the accelerating demands for water to secure food production, support
economic development and reduce poverty. To compensate for the increasingly
K. Tockner et al.