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Newsletter and Technical Publications

<Sourcebook of Alternative Technologies for Freshwater Augumentation
in Small Island Developing States>


PART B - ALTERNATIVE TECHNOLOGIES

1. TECHNOLOGIES GENERALLY APPLICABLE TO ISLAND STATES

1.4 Water Conservation

1.4.1 Water Resources Planning and Management

Planning and management of small island water resources and water development projects are closely linked to the issue of maximising and augmenting freshwater resources (UNESCO, 1991). This section provides an overview of the use of these practises in small island settings.

Technical Description

The assessment of water resources and their sustainable yields is a fundamental step in the planning of water resource development projects. Conventional water resources (e.g., surface water, groundwater, and rainwater) need to be thoroughly assessed and their use maximised before unconventional options (e.g., desalination and importation) are considered. Conjunctive use of different classes of water should always be considered in such assessments. Often rainwater catchments and shallow groundwater sources, either fresh or brackish, can be, and often are, used conjunctively, even on the smallest of islands. Rainwater may be a suitable option for the most basic of needs, such as drinking and cooking, leaving the more saline water for other uses, such as bathing and washing. Where existing or potential water supplies are scarce, the use of dual or multi-quality supplies are alternatives to be considered (e.g., using seawater for toilet flushing).

In the planning and design of water resource development projects for small islands, certain basic criteria should be adopted. Simple, proven designs, which have been used in similar conditions, should be promoted. However, it is important to recognize that technical criteria from other regions are only to be used as guidance, and must be adapted to suit local conditions, taking into account local environmental conditions, social customs, and community needs. Locally-available materials should be used where possible to minimise import costs, and materials and equipment should be standardised to minimise the level of knowledge or experience (and, more practically, the variety of spare parts required) for operation and maintenance. Diversification of technologies is a particular problem when materials and equipment is received from donor agencies. To avoid this problem, it may be necessary to specify preferred and well-tested equipment as a prior condition to receiving aid funding. In any event, corrosion-resistant materials should be used in water supply construction in SIDS due to their proximity to the sea and airborne salt spray. Wherever possible, operation and maintenance requirements should be such that they enable village-level operation and maintenance. Using renewable energy sources (e.g., solar- or wind-power), which are typically available in abundance in SIDS, for pumping should be considered as a means of minimizing operating costs.

Appropriate protection and management policies are essential for water resource development. Controls on abstraction must be introduced and backed by enforceable legislation to ensure that over-utilisation of water resources does not occur. Water resources also should be regularly monitored for quantity and quality and necessary remedial action taken to prevent over-utilisation or degradation. Appropriate water quality criteria should be set by each country. Guidelines (e.g., WHO, 1993) should be adapted to suit local conditions. For example, salinity criteria (e.g., chloride ion concentrations) need to be carefully considered in the knowledge that island populations are often accustomed to higher salinities in drinking water than are specified in many guidelines. Provided there are no adverse health or environmental effects, adapting guidelines to suit local conditions is often appropriate. Such actions help to conserve and manage available resources so as to make optimal use of conventional water resources.

Where freshwater resources are very limited, non-potable water use should be encouraged for bathing and washing where practicable. Dual piped systems, one with potable and the other with non-potable water (e.g., salt water), can contribute to reducing the demands on potable water reserves. Other conjunctive-use schemes (such as rainwater storage) may be considered where piped systems are not present (e.g., use of non-potable well water for bathing and washing). This is particularly appropriate in crowded areas where homes or living quarters may be located above or adjacent to water supply sources. Demand management is important for water resources management on small islands. In urban areas, in particular, demand management measures should include an appropriate pricing policy combined with consumer information on the need for reduction of waste. Waste reduction measures may include reducing water supply pressure to minimum levels, installing low-flow fixtures, and using water conserving devices. An active leak detection and repair program is also essential for both delivery systems and individual household systems, as many water supply systems often have substantial losses due to leaks. The savings in water can often have positive benefits in delaying the need for development of new, often more costly water resources.

Land management is very important for water resources protection, and especially so for protecting fresh, groundwater lenses from contamination. This is particularly important on islands with highly permeable soils and shallow water tables. Water reserves, or protection zones, should be established wherever possible, although such actions may result in conflicts over land ownership and can lack cultural acceptability. On atolls, it may be possible to reserve individual islands for water supply purposes (UNESCO, 1991; Falkland, 1991). Such reserves should disallow land uses which have the potential to pollute water resources, including such land uses as residential, commercial and industrial development. Where land resources are very scarce, an alternative approach would be to site such development on the edge of the island or as far as practicable from the centre of the freshwater lens. Transmigration, or resettlement of people from overcrowded islands to other locations, may be necessary in extremely serious situations (relocation has been effected in the past, and may be necessary in the future, in the event of major natural disasters such as earthquakes, volcanic eruptions, overtopping by waves, or extreme drought). Such disasters not only affect water supplies but also most of the other aspects of a small island community infrastructure.

To maximise the quantity of fresh, groundwater, it may be prudent to selectively clear vegetation, particularly coconut trees, to reduce transpiration. This selective process should be properly planned as coconut trees are a source of food and drink, shade and materials for building, as well as other purposes (likewise, other large trees, may also need to be assessed as to their suitability in groundwater abstraction areas). Similarly, to maximise the quality of fresh, groundwater, it is necessary to maintain adequate spacing between onsite sanitation systems (pit latrines and septic tanks) and water supply points (dug wells and boreholes), and to take into account groundwater flow directions. Because guidelines from non-small island states may not necessarily be applicable to the conditions prevailing in SIDS, specific guidelines should be adopted to suit local hydrogeological conditions. To this end, a UNESCO study is being carried out in Tonga to assess issues such as safe distances between wells and sanitation facilities on small islands. Where possible on small, coral islands, water supply extraction facilities should be located toward the middle of the island and sanitation and solid waste disposal facilities should be situated near the edge of the island. It might also be of benefit to review the current sanitation methods used on such islands in order to determine the relative advantages of alternative technologies in conserving water and protecting groundwater resources. In certain circumstances where land disposal of wastewater is not practical, it may be necessary to pipe sewage from the island via an ocean outfall, and, where environmental safeguards are paramount, extensive and costly sewage treatment may be necessary prior to such discharge (Gersekowski, 1992). To minimise other sources of pollution, restrictions on location of animals, such as pigs and poultry, and the siting of graveyards, bulk storage facilities and industrial facilities, may be appropriate. Potentially harmful chemicals and other substances should be located away from water supply sources.

Level of Involvement

The community should need and want the water resources development scheme. The desire for the scheme should be genuine and the community should have sufficient resources to operate and maintain the system once it is implemented. Project workers, if from outside the beneficiary community, should get to know the community and its leaders, helping them to learn how to implement and maintain the scheme, and learning from the community about their specific needs relative to the system design. There should be a management committee for the scheme ensuring that all groups are represented, particularly the women of the community

To achieve real community ownership, participation by the community at all stages is essential. Participation should begin as early as possible, and, ideally, the community should take the lead in the planning and implementation of the selected scheme. In some cases, this may require training to strengthen local capabilities for financial control and project management, and to create a degree of familiarity with the technology and its operation. The selected technology should be least complex technology that will meet immediate needs, capable of being expanded to accommodate future needs, and within the capability of the community to install and maintain. Time scales relating to project implementation should be flexible enough to allow the community to work at its own pace, using methods appropriate to the community.

Participation by the community is a fundamental component of any water resources development project; it is both the means by which projects are implemented and the essential ingredient for project success and community development. In this regard, cost recovery schemes should be considered in order to recover all or part of the capital cost of a project and foster the community=s sense of ownership. Whether or not a project can be sustained depends crucially on the community=s willingness to take responsibility for the operation and maintenance of selected system. This willingness is often apparent by the extent to which people participate during the planning and implementation of the project. Social scientists have devoted much attention to the study of community participation, and most agree that, while many programmes pay lip service to the concept, very few programmes realise or appreciate its full potential. Rather, community participation is often viewed, mistakenly, as some kind of injection which can be given to a programme at various points during the project cycle, and, more often than not, as a nuisance for the technical personnel geared to the more technical aspects of project design and implementation.

Further Development of the Technology

Training at technical, professional and managerial level is required as an ongoing requirement to improve the skills of local personnel in the assessment, development and management of their own water resources, and the selection of appropriate water supply technology. The training of women in the operation and maintenance of water and sanitation systems is essential as it is the women who are most affected by faulty water and sanitation systems. Recognition among water resources professionals of the important role of communities in the design, operation and maintenance of water supply systems is also critical and techniques for community-based decision-making should be developed and included in professional training programmes.

Information Sources

Anon. 1984. Proceedings of the Regional Workshop on Water Resources of Small Islands. Commonwealth Science Council, London.

Anon. 1991. Water Resources Management in Small Island Countries: Cost Recovery and Demand Management. Water Resources Journal, September, 8-12.

Beran, M.A. Rodier 1985. Hydrological Aspects of Drought : a Contribution to the International Hydrological Programme. Studies and Reports in Hydrology No. 39, UNESCO, Paris.

Buddemeier, R.W. and J.A. Oberdorfer 1986. Internal Hydrology and Geochemistry of Coral Reefs and Atoll Islands: Key to Diagenetic Variations. In: J.H. Schroeder and B.H. Purser (Eds), Reef Diagenesis. Springer-Verlag, Berlin. pp. 91-111.

Dale, W.R. (Ed.) 1985. A Bibliography of Hydrogeology of Small Islands: a List of Some Recent Publications with Particular Reference to Coral Reef Islands of the Pacific. Commonwealth Science Council Technical Publication Series 183.

Dale, W.R., and B.C. Waterhouse 1985. Pacific Islands'Hydrogeology and Water Quality. In: Environment and Resources in the Pacific. UNEP Regional Seas Reports and Studies 69: 57-67.

ECAFE Secretariat [Economic Commission for Asia and the Far East] s.d. Water Legislation and Management in Western Samoa. Economic Commission for Asia and the Far East, United Nations, New York.

ESCAP [Economic and Social Commission for Asia and the Pacific] 1983a. Water Resources in South Pacific Island Countries and the Trust Territory of the Pacific Islands. Water Resources Development in the South Pacific Working Paper No. 1, Water Resources Series No. 57, United Nations, New York. pp. 21-31.

ESCAP [Economic and Social Commission for Asia and the Pacific] 1983b. Water Resource Development Problems in South Pacific Island Countries and the Trust Territory of the Pacific Islands. Water Resources Development in the South Pacific Working Paper No. 2, Water Resources Series No. 57, United Nations, New York. pp. 33-40.

ESCAP [Economic and Social Commission for Asia and the Pacific] 1992. Towards an Environmentally Sound and Sustainable Development of Water Resources in Asia and the Pacific. Water Resources Series No. 71, United Nations, New York. p. viii.

Falkland, A.C. 1991. South Island Water Resources Study, Cocos (Keeling) Islands. Report No. 91/2, Hydrology and Water Resources Section, ACT Electricity and Water, Canberra.

Falkland, A.C. 1992. Small Tropical Islands: Water Resources of Paradises Lost. IHP Humid Tropics Programme Series 2, UNESCO, Paris.

Falkland, A.C. 1993. Hydrology and Water Management on Small Tropical Islands. In: Hydrology of Warm Humid Regions, IAHS Publication No. 216: 263-303.

Gersekowski, J.N. 1992. Sewage Treatment on Green Island. In: Proceedings of the National Conference on Environmental Engineering, Institution of Engineers, Australia, Gold Coast. pp. 175-179.

Goodwin, R.S. 1984. Water Resources Development in Small Islands, Perspectives and Needs. Natural Resources Forum, 8(1):63-68.

Hufschmidt, M.M. and J. Kindler s.d. Approaches to Integrated Water Resources Management in Humid Tropical and Arid and Semiarid Zones in Developing Countries. UNESCO Technical Documents in Hydrology. UNESCO, Paris.

Papua New Guinea Department of Environment and Conservation 1989. Review of Papua New Guinea Water Resource Legislation: Outline of Recommended Changes to Water Resources Act 1982. Department of Environment and Conservation, Boroko, PNG.

Pickford, J. 1991. The Worth of Water, Technical Briefs on Health, Water and Sanitation with an Introduction by John Pickford. Intermediate Technology Publications, London.

Pulea, M. 1983. An Overview of Environmental Protection Legislation in the South Pacific Countries. South Pacific Regional Environment Programme, Topic Review 13. United Nations Environment Programme, Nairobi. (updated version of 1981 by S. Venkatesh and S. Va'ai).

Roy, P. and J. Connell 1991. Climatic Change and the Future of Atoll States. Journal of Coastal Research, 7:1057-1075.

UNESCO [United Nations Education, Scientific and Cultural Organization] 1991. Hydrology and Water Resources of Small Islands, a Practical Guide. Studies and Reports on Hydrology No. 49, UNESCO, Paris. 435 pp.

United Nations 1981. Proceedings of the Seventh Session of the Committee on Natural Resources Committee on Natural Resources: United Nations, 1981. United Nations Water Resources Series No. 54, 284-293.

United Nations 1986. Water Resources Legislation and Administration in Selected Caribbean Countries. United Nations Natural Resources/Water Series No. 16, United Nations, New York.

United Nations Department of Technical Cooperation for Development 1990. Water Resources Management Techniques for Small Islands: a United Nations Interregional Seminar Convened in Cooperation with the Government of Fiji, Suva, Fiji, 26 June to 1 July 1989: Summary Report, Conclusions and Recommendation. United Nations Development Programme, New York.

United Nations Environment Programme 1990. Water-related Issues and Problems of the Humid Tropics and Other Warm Humid Regions. UNEP, Nairobi.

United Nations Department of Technical Cooperation for Development 1989. Interregional Seminar on Water Resources Management Techniques for Small Islands, Suva, Fiji, 26 June to 1 July 1989: Report of the Meeting. United Nations Development Programme, New York.

United Nations Department of Technical Co-operation for Development 1990. Water Resources Management Techniques for Small Islands. United Nations Development Programme, New York.

Waterhouse, B.C. and D.R. Petty 1986. Hydrogeology of the Southern Cook Islands, South Pacific. New Zealand Geological Survey Bulletin 98, DSIR Science Information Publishing Centre, Wellington.

Wheatcraft, S.W. and R.W. Buddemeier 1981. Atoll Island Hydrology. Ground Water, 19:311-320.

WHO [World Health Organization] 1989. Decade Progress and Problems in Pacific Island Countries. World Health Organisation Interregional Seminar on Water Resources Management Techniques for Small Island Countries Report No. ISWSI/SEM/23, WHO, Geneva.

WHO [World Health Organization] 1993. Guidelines for Drinking-water Quality. WHO, Geneva.

Wright, E.P. 1984. Water Law. In: Proceedings of the Regional Workshop on Water Resources of Small Islands. Commonwealth Science Council Technical Publication No. 154, Part 2, 55-66.

Wright, E.P. 1989a. Chapter 12. Small High Islands. In: M. Falkenmark and T. Chapman (Eds), Comparative Hydrology: an Ecological Approach to Land and Water Resources, UNESCO, Paris. pp. 295-322.

Wright, E.P. 1989b. Chapter 18. Small Low Islands. In: M. Falkenmark and T. Chapman (Eds), Comparative Hydrology: an Ecological Approach to Land and Water Resources, UNESCO, Paris. pp. 393-404.

Zhao, W., R. Liang, and Y. Zhou 1988. Application of Database Management System for Hydrological Data to Small Islands. In: Proceedings of the Southeast Asia and the Pacific Regional Workshop on Hydrology and Water Balance of Small Islands, UNESCO/ROSTSEA, Paris. pp. 95-106.

Zucker, W.H. 1985. Ecology and Environmental Health Implications of Water Resource Development in Small Islands. In: Water Resources of Small Islands: Technical Proceedings (Part 2) of the Regional Workshop on Water Resources of Small Islands, Commonwealth Science Council, London. pp. 520-523.

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