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Abbie Trayler-Smith / Panos Pictures / Department for International Development

Chapter 8.2 Communities and technology: choice and innovation

Appropriate technology

Photo: Abbie Trayler-Smith / Panos Pictures / Department for International Development

In the past, high-tech, large-scale technologies have tended to be prominent in DRR: for example, embankments, dams and dykes for flood control, advanced methods of securing buildings against earthquakes and cyclones, irrigation systems that deliver large quantities of water, and walls and banks to restrain volcanic debris. They are typically applied in wealthy countries and societies, or in poorer countries through large projects financed by international aid agencies.

An alternative approach encourages the development and use of what is often called ‘alternative’ or ‘appropriate’ technology. These terms can be defined and understood in different ways, but in practice they usually refer to smaller-scale technologies that can be owned and managed by households or communities, and that integrate environmental, economic and social sustainability. Appropriate technology has long featured in development programming, where there is a great deal of experience to draw upon.+I. Smillie, Mastering the Machine Revisited: Poverty, Aid and Technology (London: ITDG Publishing, 2002). There is also a growing body of knowledge about appropriate technologies in DRR, linked to better understanding of indigenous knowledge and coping strategies. At community level, both development and DRR initiatives can benefit from using appropriate technologies, because:

  • they are small-scale, and hence suitable for local-level application;
  • they are low-cost, and hence more affordable for poor households and communities, as well as technical assistance programmes;
  • they are likely to be suited to local people’s technical and managerial capacities;
  • they draw on indigenous knowledge and skills;
  • they are owned and controlled by local people; and
  • they offer poor and vulnerable communities a wider range of choice than expensive, complex, high-tech solutions.

There are many potential applications of smaller-scale and appropriate technologies to DRR, including making housing more secure against hazards such as floods, earthquakes and high winds; building local-level infrastructure (e.g. footbridges and tracks); and constructing small-scale hazard mitigation structures (e.g. flood or landslide defences, rainwater harvesting structures). Many of the best-known examples come from the fields of food security (see Chapter 14) and housing, where there is an extensive literature, but it is important for project managers to take a broad view of the opportunities for alternative technology.

Case Study 8.1 Floating gardens

In Bangladesh, where many people are landless and farmland is flooded for parts of the year, ‘floating gardens’ provide poor households with food and income. The gardens are relatively inexpensive, generally using aquatic weeds such as water hyacinths as a floating base, overlaid with bamboo topped with mulch, compost or other organic material. Once this material has rotted down, a range of vegetables can be grown. The rafts can be moved to sunnier or shadier spots, and can be re-used and their materials recycled.

The technology is traditional in the wetlands of southern Bangladesh. Since the late 1990s several NGOs have promoted it in other parts of the country. In one project in northern Bangladesh in 2010–12, 700 families built 1,500 floating gardens, which kept them supplied with vegetables during the monsoon season. In 2013 the government of Bangladesh launched a three-year programme to promote the technology in eight districts across the country.

N. Noble, Floating Gardens in Bangladesh (Rugby: Practical Action, 2000),; H. M. Irfanullah, ‘Floating Gardening: A Local Lad Becoming a Climate Celebrity’, Clean Slate, 88, 2013,

8.2.1 Cost and materials

While high-tech measures have helped to protect many people in wealthier societies, their high cost means that they are not applied or are even inapplicable to poor and vulnerable communities in the global South. Smaller-scale technological inputs are more likely to be affordable by less well-off households and communities. The materials that are used can often be found locally. For instance, stone is used in a wide variety of hazard-mitigating structures, including dams and water tanks, bunds that hold back water on fields and retaining walls and gabions (wire cages filled with rocks) to support unstable hillsides or protect gullies from erosion. In Bangladesh, earth mounds provide shelter for people and animals as the water rises. These can be built cheaply in most villages, using local labour. Hazard-resistant houses can be built from locally grown wood and bamboo. Recycled materials can also be used. For example, retaining walls made of old car tyres filled with compacted earth and tied together can stabilise slopes.

Outsiders often fail to appreciate that many poor people, who rely on day wages and have little or no savings, may not be able to afford even relatively simple technical improvements that will make them safer. This raises the question of how poor people are to pay for improvements that they cannot normally afford. Simply providing such things free of charge is ineffective: people are less likely to appreciate the usefulness of the donations, which means that they are less likely to use them efficiently, and they tend not to look after them properly. Some kind of financing mechanism is generally needed, such as soft loans and hire-purchase arrangements (Chapter 12 discusses financing DRR more generally). One commonly used non-financial alternative is to ask project beneficiaries to give their time and labour to a housing or community infrastructure project in return for benefiting from the project.

It can be cost-effective to use cheaper materials or structures that can be more easily replaced by local people. For instance, in irrigation systems in mountainous areas it may be better to build stone and brushwood dams than to install stronger steel and concrete structures. Seasonal rains and consequent landslides are likely to wreck the stone and brushwood dams every year, but they can be replaced using materials readily to hand. More sophisticated structures are unlikely to fail unless rainfall and landslides are exceptionally severe, but one never knows when exceptional weather will occur, and if they do collapse, the money, materials and skills to rebuild them may not be available. A similar argument can be used to justify retaining seemingly flimsy bamboo and thatch housing. Although such houses are much more vulnerable to floods than houses made of more resilient material such as brick, they can be replaced more easily. Parts can even be dismantled and carried away to safety if sufficient warning is given.

8.2.2 Effectiveness

Many disaster managers and their counterparts in development tend to feel that appropriate technologies are somehow second-rate: at best a compromise, at worst ineffective. Decades of development experience in poor and vulnerable communities have shown such views to be misguided.+Smillie, Mastering the Machine Revisited: Poverty, Aid and Technology. Appropriate technologies take a wide variety of forms and approaches, drawing on old and new ideas, and there is plenty of technical innovation in this area. Small-scale, low-cost alternative technologies can be highly effective in reducing risk, are highly replicable and can spread over a very wide area. Like indigenous knowledge generally, of which they are part, traditional technologies are often well adapted to prevailing hazards. Many societies have highly effective and sophisticated water capture, storage and irrigation systems which have been in operation for hundreds of years, including the Karez systems in China’s Xinjiang region and the connected ‘cascade’ reservoir systems in Sri Lanka. In the 2005 Kashmir earthquake, the flexibility of traditional timber buildings meant that they tended to stand up well to the shaking compared to other structures.+W. Fang et al., ‘Karez Technology for Drought Disaster Reduction in China’; A. A. Khan, ‘Earthquake Safe House Construction Practices in Kashmir’; C. M. Madduma Bandara, ‘Village Tank Cascade Systems: A Traditional Approach to Drought Mitigation and Rural Wellbeing in the Purana Villages of Sri Lanka’, in R. Shaw et al., Indigenous Knowledge for Disaster Risk Reduction: Good Practices and Lessons Learned from Experiences in the Asia-Pacific Region, European Union/UNISDR Regional Office for Asia and Pacific, 2008,, pp. 1–4, 5–8, 68–72.

Nevertheless, the attraction of what is thought to be ‘modern’ technology is very strong among poor communities. This can hinder the adoption of safe technologies that are perceived to be primitive; it can also lead to the use of unsafe technologies that are perceived to be modern. The chances of short-term success and long-term sustainability are greatly enhanced if technical innovations directly improve poor people’s livelihoods. This link is commonly seen in technical measures for mitigating drought, such as soil and water conservation, multi-cropping and growing indigenous drought-resistant crops. All of these are clearly linked to improving food security and hence livelihoods.