Newsletter and Technical Publications
<Sourcebook of Alternative Technologies for
in Small Island Developing States>
PART A - INTRODUCTION
3. STRUCTURE OF THE SOURCE BOOK
The Source Book is in three major parts:
- - Part A provides an introduction to freshwater augmentation: what it
is and why it is necessary. Part A also outlines the purpose of the
Source Book; reviews the methodology used in this Source Book for the
classification of "small islands"; and, presents an overview
of how to use the Source Book.
- - Part B briefly describes a series of alternative technologies
available and used in Small Island Developing States (SIDS), and
presents a consistent and comparable set of data about the technologies
which can be used to compare their relative advantages for maximizing
water-use efficiency and augmenting existing water supplies in small
island states. The objective of these technology profiles is to provide
a reasonably comprehensive inventory, summarised in Table 1, that water
resources professionals can use when planning water development projects
- - Part C comprises case studies that highlight specific technologies
that have been adopted in the region, and summarizes the experiences
gained from their implementation.
For the purpose of this Source Book, the technologies applicable to
Small Island Developing States, discussed in Part B, are divided into four
- - The first subsection reviews those technologies that are generally
applicable to small islands regardless of their geological and
topographical configuration. These include technologies such as
alternative (dry) sanitation, water quality improvement, irrigation
systems, and water conservation and groundwater assessment technologies.
- - The second subsection reviews those technologies applicable to very
small, low coral islands. These include technologies such as rainwater
harvesting and groundwater abstraction techniques such as dug wells and
infiltration galleries, as these islands are not likely to have surface
water resources and moderate to low availability of groundwater
- - The third subsection reviews those technologies applicable to
small, high volcanic islands which are likely to have greater options
for water resources development. These include technologies for the
development of rainwater, surface water and groundwater resources.
- - The fourth subsection covers islands where specific problems or
circumstances make it necessary to pursue alternative (and not so
commonly used) technologies. These include technologies such as
desalination, dual water distribution systems, importation, and
Summary of Freshwater Augmentation Technologies Applicable
to Small Island Developing States.
Figure 1. Possible applications of water supply
technologies for small high islands.
Figure 2. Possible applications of water supply
technologies for small low-lying islands.
It should be noted that there are no fundamentally new technologies
available to resolve the difficulties imposed on SIDS by their limited
water resources. For very small, coral islands, either rainwater or
groundwater is available. Most SIDS cannot afford desalination as an
option, and importation of water by barge or submarine pipeline,
similarly, is not often feasible. Small volcanic islands often have
surface water as a third option, together with rainwater and groundwater.
However, desalination and importation, likewise, are rarely used and only
where there is no other feasible alternative and consumers can afford to
pay for it. For these reasons, emphasis is placed on conserving and
protecting the quality of the existing water resources. Pollution of
groundwater and surface water resources is increasing due to untreated
human waste discharges from individual households, hotels and industries,
and urgent steps need to be taken to halt or minimise pollution of these
water resources. Similarly, the water that is supplied to consumers is
often wasted, and/or lost through delivery system leaks and illegal
connections, and improved management of water resources and supply systems
is needed. Often water is supplied without charge, even though costs are
incurred in providing and maintaining the supply service. The technologies
described in Part B address many of these issues.