Stone Lines Or Earth Dikes
issue 183 - May 1988
Stone lines or earth dikes
Paul Harrison argues that development agencies willing to keep it
simple and learn from the ancient wisdom of Third World peasants have
a greater chance in the long run of meeting people's basic needs.
Nowhere in the world have conventional agricultural projects and policies failed as spectacularly as in Africa.
Among World Bank projects reviewed in 1985, almost one in three failed in West Africa. In East Africa, the figure jumps to more than half. And the long-term outcomes are even worse. The Bank made a special study of 17 African agriculture projects considered successful at completion. When these were followed up after another five and ten years, 13 failed to meet expectations.
Results like these have made the mighty Bank unusually humble when dealing with Africa. According to their own evaluations one of the major reasons for this startling lack of success was that those affected by the projects were not involved in designing them. This was made worse by the wholesale introduction of unfamiliar techniques that brought major upheavals in traditional ways of living. For example, nearly all African farmers grow their crops in mixed rather than single stands: they mingle in the same field millet and cowpeas, cassava and maize, coffee and bananas. Most visiting Western experts find this traditional practice of intercropping messy. They want so bring in tidy fields of single crops, where set amounts of fertilizer and pesticide for each crop can be easily applied and mechanization is easy to introduce. It is no surprise that most such attempts have failed.
The African farmer turned out to be right all along. Researchers are now finding that intercropping may produce less of each individual crop, but it gives a higher total output than monocropping. Pests are less of a problem. The soil cover is denser and erosion not as severe. And intercrops are less likely so fail disastrously in bad years than monocrops.
Agronomists love to talk about 'packages' of improved seeds, fertilizers and techniques they can offer to farmers. Yet the more changes these packages require, the less likely they will be accepted by peasants for whom failure may mean death. Attempts to make nomadic pastoralists behave like American ranchers, keeping their herds within fenced boundaries or rotating the areas on which they graze, have flopped miserably. So have efforts to replace natural forests that provide fuel, grazing, herbs, medicines and honey with plantations of exotic trees like conifers, which provide only timber or fuelwood.
So what is the answer? While I was researching The Greening of Africa I visited 20 projects that succeeded.
One of the most spectacular successes was Oxfam's program of stone lines for soil and water conservation in the northern part of she West African country of Burkina Faso. Vast areas in the northern half of the country have been turned into barren desert, hundreds of miles south of what not long ago was the edge of the Sahara. When the soil is partly eroded and cleared of vegetation cover it begins to form a crust as smaller particles wash off and clog the pores between larger ones. The crust prevents any further water from entering she soil. So even in wet years, when the rains are pouring down, they do not soak into the dry earth, leaving plant roots parched. Grasses die, then shrubs, and finally trees.
In the early 1960s, the European Development Fund tried to solve the problem of erosion and water conservation in the usual expensive large-scale fashion by building thousands of kilometres of low earth dikes in line with the natural contours of the land. The farmers were not consulted or even informed what these strange earth banks were for. Very quickly they pierced through them with cycle and cattle tracks or even flattened them out entirely.
After the drought of 1973 and 1974, local farmers began to try out a traditional solution: piling heavy stones in the path of the water. But their lines did not follow the contours. Water piled up as low points and poured through, causing worse erosion than before.
Taking his lead from the Burkinabe farmers, Oxfam project director Peter Wright began working together with peasants to look for ways of improving food production using the traditional stone dams. He found the peasants' own approach worked very well as a water-harvesting technology. If the dams were built more solidly and aligned with the natural contours of the earth, they slowed down the run-off water and dammed much of it back uphill, giving it time to sink into the dry earth. Soil erosion was slowed or halted, and crops got a lot more moisture. Millet yields increased by 50 per cent on average and up to 100 per cent in drier years.
Oxfam then held training sessions for peasants to teach them how to build the lines along the contours of the hills. Trendsetters built them immediately: their neighbours followed the very next year as soon as they saw the difference in millet yields. Only seven years after the first pioneer efforts, the lines are now almost everywhere in northern Burkina Faso. Not only do they prevent crusting, but they can also rescue desertified wastelands, as new soil, dead leaves and seeds come to rest against the lines, and water can once again soak in.
Improved wood stoves are another remarkable African success. After many failures, the Burkina Institute of Energy developed a simple stove design made from a mixture of clay, millet chaff and dung that Burkinabe women could easily make themselves. By the end of 1987, there were around 200,000 of these new stoves already in use. They not only help to reduce deforestation, they reduce the amount of time rural women need to spend searching for fuel - which can often be an hour a day or more.
These two projects have a lot of common lessons for other development programs in Africa and indeed in other poor rural areas.
They use free and easily available local materials. They cost nothing in cash to make. They do involve labour - quite a lot in the case of the stone lines - but it is work that can be done in the dry season when it does not conflict with crop production. They add no extra risk to lives that are already exposed to severe risks from climate and pests. They offer a handsome and rapid payback.
They are also simple to make and to maintain and both are based on an improvement of traditional techniques, familiar to and trusted by local people. They fit easily into existing patterns of activity - women can go on cooking in the same pots as before, and farmers can go on growing the same crop mixtures in between the lines as before.
They tie in well with local realities because they were not designed in isolation by far-away technical experts; instead they were developed in close consultation with the eventual users.
Because they use free local materials and emphasize self-help, they also avoid other traps into which large-scale aid projects often fall headlong: excessive reliance on imports, high-cost inputs and government backup. None of these are guaranteed in Africa where budgets and balance of payments are in permanent crisis.
Paul Harrison is author of The Greening of Africa, Penguin Books, 1987.