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International Programme for Technology and Research inIrrigation and Drainage

SMALLHOLDER IRRIGATION TECHNOLOGY:

PROSPECTS FOR SUB-SAHARAN AFRICA

Melvyn KayFAO/IPTRID Consultant

IPTRID SecretariatFood and Agriculture Organization of the United NationsRome, 2001

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© FAO 2001

The views expressed in this paper are those of the authors and do not necessarily reflectthe views of the Food and Agriculture Organization of the United Nations (FAO) or theInternational Programme for Technology and Research in Irrigation and Drainage(IPTRID). Mention of specific companies, their products or brand names does not implyany endorsement by FAO or IPTRID

Smallholder irrigation technology: prospects for sub-Saharan Africa iii

Summary

This report is a review of irrigation technologies for smallholders in the context of improving rural livelihoods,especially in regard to the prospects for sub-Saharan Africa. The role of traditional technologies is evaluatedand modern water distribution technologies, such as sprinkler and trickle irrigation, are reviewed. Low-costirrigation systems, including such innovations as the use of treadle pumps and drip-kits are then examined.The most appropriate technology to use varies from place to place depending on a wide range of circumstances.A broad classification has been made based on climate and the traditional agricultural background of the localpeople, which links technology options to specific places – to agricultural regions and to countries. Someideas are presented on the direction that might be taken by governments, aid donors, NGOs and the privatesector to support future development, with a special emphasis on the need to support a wide range ofeducation and training programmes.

THE CASE FOR SMALLHOLDER IRRIGATION

Irrigation has long been seen as an option for improving rural livelihoods by increasing crop production, butmassive investments throughout the 1970s and 1980s in sub-Saharan Africa have not borne fruit. Foodproduction targets were not met, development costs were extremely high in relation to returns and therewere many technical and management problems that remain unsolved. The decrease in real terms of worldcereal prices over the past decade has made it difficult to invest in and maintain irrigated agriculture for basicgrain crops.

Much of this criticism was directed at the more formally structured irrigation schemes usually under thecontrol of a government body. Because of this, attention turned in the 1980s to the informal sector, small-scale or smallholder irrigation, which is described as the ‘bottom-up’ or ‘grass-roots’ approach to development.There are many smallholder success stories, particularly where farmers have made the investments themselves.

However, all has not gone smoothly where donors have tried to stimulate development. Donors, fundingagencies and national governments, wishing to accelerate the development process, still tend to use a ‘topdown’ approach where only lip service is paid to farmer participation. The pace is forced to meet investmenttargets and market forces have been ignored.

AVAILABLE TECHNOLOGIES

Experience in sub-Saharan Africa has shown that successful smallholders generally use simple technologiesand have secure water supplies over which they have full control. The most successful technologies arethose that improve existing farming systems rather than those that introduce radically new ideas.

Traditional technologies

A wide range of well-established traditional technology options is available for use by smallholders includingof water harvesting, swamp irrigation, spate irrigation, flood plain irrigation using seasonal water and shallowaquifers, hill irrigation, and groundwater irrigation. There is still, however, considerable room to improve andadapt these traditional technologies to different circumstances.

Modern technologies

In recent years there has been a growing interest in new technologies to carry and apply water. Theseusually cost much more than traditional methods and rely very much on external specialist support from

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suppliers and distributors. Distribution technologies such as trickle and sprinkle irrigation and piped suppliesfor the more traditional surface methods, can help farmers to manage their water better as well as reducingwastage. All these technologies have the potential to raise the productivity of water and labour. But they arereally only accessible to those farmers who can afford to buy them and who are growing cash crops such asvegetables, fruits and flowers. They are unlikely to be taken up by poor farmers.

Low-cost technologies

This phrase refers to modern technologies that have been developed or modified in some way to bring downtheir cost. An excellent example is the treadle pump, which was developed specially as a low-cost pump forsmallholders and continues to be adapted for particular local needs and markets in the region. Low-costsystems of water conveyance and distribution have not been comprehensively tested and evaluated in theregion, with the exception of treadle pumps. The adoption by smallholders of treadle pumps to replace theonerous task of lifting and carrying water and the way in which the support services have developed offerslessons for the promotion of other irrigation technologies.

TECHNOLOGY UPTAKE

Low-cost, modern technologies can help smallholders move from subsistence farming into growing cashcrops. Success will be determined more by the capacity of smallholders to take risks and adopt new technologiesin situations where services are erratic, costs are high and markets are unpredictable. Factors influencingtechnology uptake are the existence of a market-driven demand for agricultural produce; a well-designedtechnology that is both appropriate and affordable for the local farming and manufacturing systems; a localprivate sector capable of mass production of reliable equipment; effective private sector distribution networksfor agricultural inputs and equipment including transport, infrastructure and retailers.

HOW FAST CAN IRRIGATION DEVELOP?

The average rate of irrigation development for the sub-Saharan Africa region (40 countries) over the past 12years is 43 600 ha/year – an average of 1 150 ha/year for each country. Some countries have average ratesof development over 2 000 ha/year (e.g. Tanzania, Nigeria, Niger, Zimbabwe and South Africa).

If the current rate continues over the next 25 years then an extra one million ha of irrigation could bebrought into production – increasing the total area presently under irrigation by 50 percent. Even at the mostoptimistic rate, the contribution that irrigation can make to increase food production in the region will bemodest unless some of the key constraints are removed.

Speeding up development does not necessarily mean building irrigation schemes faster but building manymore of them. An important lesson learned over the past 20 years is that smallholder schemes developthrough a slow incremental process of improvement, usually in response to farmer demand. Unfortunatelythis is at odds with the way in which most donor and government agencies work to specific time schedules.

A DEARTH OF EXPERIENCE

For irrigation to succeed, experienced and knowledgeable staff will be needed. Labour studies can assess thedemand and supply of trained people. Demand is based on the expected growth rates in irrigation and thesupply of trained people at all levels is based on the output from both the institutional and in-service trainingarrangements. Support will undoubtedly be required in order to establish appropriate institutional and in-service training programmes that properly equip people for the jobs they must do to address the fundamentalissues related to the improvement and adoption of appropriate irrigation technologies in sub-Saharan Africa.

Smallholder irrigation technology: prospects for sub-Saharan Africa v

Contents

SUMMARY ...................................................................................................................................................... III

ACKNOWLEDGEMENTS .................................................................................................................................... VI

INTRODUCTION ................................................................................................................................................ 1The case for smallholder irrigation .................................................................................................... 1Too many reviews? ............................................................................................................................... 2Technology – at the heart of irrigation .............................................................................................. 2The nature of smallholder irrigation .................................................................................................. 3

TRADITIONAL TECHNOLOGIES .......................................................................................................................... 5Water harvesting .................................................................................................................................. 6Communal scheme experiences ........................................................................................................ 9Role of traditional technologies in sub-Saharan Africa ................................................................. 11

MODERN TECHNOLOGIES .............................................................................................................................. 13Sprinkle irrigation............................................................................................................................... 14Trickle irrigation ................................................................................................................................. 17Improving traditional methods ......................................................................................................... 18A role for modern technologies in sub-Saharan Africa? ............................................................... 19

LOW-COST TECHNOLOGIES ........................................................................................................................... 21A new philosophy ................................................................................................................................ 21Irrigation kits ...................................................................................................................................... 21Treadle pumps..................................................................................................................................... 24Prerequisites for uptake .................................................................................................................... 25A role for low-cost technologies in sub-Saharan Africa? .............................................................. 25

MATCHING TECHNOLOGIES TO AGRICULTURAL REGIONS ................................................................................. 27Desert and semi-desert ..................................................................................................................... 27Dry savannah agriculture................................................................................................................... 27Humid savannah agriculture ............................................................................................................. 29Humid tropical forest agriculture ..................................................................................................... 29High tropical and subtropical plateau agriculture ......................................................................... 29

HOW FAST CAN SMALLHOLDER IRRIGATION DEVELOP? .................................................................................... 31Review of experience from sub-Saharan Africa ............................................................................. 31Existing situation ................................................................................................................................ 34Future potential .................................................................................................................................. 36

THE RIGHT DIRECTION: PROSPECTS FOR SUB-SAHARAN AFRICA ...................................................................... 39Developing human resources ........................................................................................................... 39

REFERENCES ................................................................................................................................................ 41

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The author would like to acknowledge and thank the following people for their valuable assistance during thepreparation of this report:

• Tom Brabben, Audrey Nepveu de Villemarceau, and Arumugam Kandiah, IPTRID, Land and WaterDevelopment Division, FAO, Rome

• Officers of the Water Resources Development and Management Service, FAO, Rome, particularly RetoFlorin, Martin Smith and Nico VanLeeuwen

• Michael Fitzpatrick, Amadou Soumaila and Abdul Kobakiwal, FAO, Rome

• Jean Payen, Irrigation Adviser, IFAD, Rome

• Ed Perry, Enterprise Works Worldwide, Washington DC, USA

• Peter Raymond, INPIM, Washington DC, USA

• Fernando Gonzalez, Geert Diemer and Itaru Minami of the Rural Development Department, World Bank,Washington DC, USA

• Jaap van de Pol and Volker Branscheid, World Bank, Washington DC, USA

• Richard Carter, Cranfield University, UK

• Gez Cornish, HR Wallingford, UK

Acknowledgements

This paper was prepared in response to a request from Fernando Gonzalez, Senior Irrigation Adviser in theWorld Bank. IPTRID gratefully acknowledges the financial support provided by the World Bank.

Smallholder irrigation technology: prospects for sub-Saharan Africa 1

Introduction

Irrigation has long been seen as an option to improveand sustain rural livelihoods by increasing cropproduction. It can reduce dependency on rainfedagriculture in drought prone areas and increasecropping intensities in humid and tropical zones by‘extending’ the wet season and introducing effectivemeans of water control. In the 1970s and 1980sinternational agencies and national governmentsinvested heavily in irrigation to intensify agricultureand reap the benefits of the high yield potential ofirrigated agriculture. The nature of donor-sponsoreddevelopment favoured large-scale projects ratherthan small ones and the majority of funding wentinto large-scale irrigation schemes. It is now widelyaccepted that this massive investment has not bornefruit. Food production targets were not met,development costs were extremely high, and therewere many technical and management problems thatremain unsolved. Over the past decade low worldcereal prices have not helped this situation makingit more difficult to maintain and invest in expensiveirrigated agriculture for basic food crops.

Much of this criticism of irrigation has beendirected at the more formally structured irrigationschemes usually under the control of a governmentbody. Because schemes were large, the approachwas almost exclusively ‘top-down’. Projectmanagement, to all intents and purposes, treatedsmallholders as labourers, and attempts were madeto carry out all major agricultural operations on alarge scale as a subsidized service. Dissatisfactionarose as a result of the inability of scheme managersto provide promised services such as cultivations,land grading, and harvesting on time.

THE CASE FOR SMALLHOLDER IRRIGATION

Because of the criticism, attention turned in the1980s to the informal sector. This was a significantshift from engineering led irrigation solutionstowards an interactive approach in which thefinancial, cultural and social circumstances of thebeneficiaries were to be taken into account. Thiswas irrigation practised by individual farmers orsmallholders, usually farming on a small scale (afew hectares) under their own responsibility; usually

at low-cost with little or no government support andusing technology they could understand and manageeasily themselves. It is often described as the‘bottom-up’ or ‘grass-roots’ approach todevelopment. Surprisingly, up to that point this kindof development had received very little attentionfrom the main aid donors in spite of the fact thatthis type of irrigation was already playing asignificant role in several countries.

Over the past 20 years this approach has beenthe main focus of attention. Ideas about how toincrease food production have been adjusted to takeinto account some of the physical realities of landand water use and resource allocation. For example,only five percent of the cultivated area in sub-Saharan Africa is irrigated and the rural poor aremore likely to be found on marginal land in non-irrigated and often non-irrigable agriculture. Therehas been an increased emphasis on poverty reductionand a renewed interest in alternatives to the moretraditional ways of irrigating using surface orgroundwater such as water harvesting.

In a review of a published report on smallholderirrigation for a journal it was stated that:

‘An outsider to African smallholder irrigation withfarming experience, would be amazed at the wayirrigated agriculture has been approached in theregion in recent decades. The manner in whichfarmers are given restricted and limited tenancies,told what to grow, charged for doubtful servicesand offered derisory prices for their produce wouldbe laughable to European farmers. The fact thatthis and many other documents make suchobvious statements shows how widely theexisting paradigm of development has beenaccepted.

‘The authors’ message is two-fold. First,governments and others should allow farmers tocontrol their own decisions and activities and helpthem to produce effectively. Second, the authorsstress that most African smallholders arepreoccupied with minimizing risk, and survival. Iffarming is too risky, then farmers may give priorityto other means of survival and income generation.

There are major obstacles to change that lie inthe enormous vested interests of those other thanfarmers who promote smallholder irrigation.’

Introduction2

There are many smallholder success stories butall has not gone smoothly. Too many internationalagencies and national governments wishing toaccelerate the development process still tend to usea ‘top-down’ approach. Some have grouped manyindependent smallholders together into a ‘project’for administrative convenience and created large-scale projects with their attendant problems. Therehave been too many instances of paying lip serviceto farmer participation, forcing the pace to meetinvestment targets and ignoring market forces. Themuch-used term of ‘low-cost engineering’ hasbecome a euphemism for poor engineering designand construction.

TOO MANY REVIEWS?

It is well established that the potential for irrigationin terms of land and water resources in the region issignificant. These resources do not constraindevelopment although many other factors do. Thereality is that smallholder irrigation does not meanit is simple.

Over the past 20 years a great deal has beenwritten about what has or has not been done forsmallholder irrigation. The literature available iscomprehensive, covering topics that includeappraisals of various technologies and socio-economic and anthropological studies. Much hasbeen published, but there is still much that is not inthe public domain, which may be of considerablebenefit to others and resides as ‘grey’ literature inthe archives of various organizations. Indeed, thereis a fear that a great deal of knowledge andexperience is ‘lost’ simply through changes ininternational agency and government staff, thusreducing ‘corporate memory’ to little more than adecade.

Unfortunately very little of this experience seemsto have found its way into current developmentpractice. The question remains as to how thispotential, in terms of the available natural resources,can be realized. Some argue that market forces willdrive development if the price of food crops isenough to encourage farmers to increase production.The rewards for meeting market demands can behigh but so too can be the risks of failure. Otherssuggest that development can be driven by aidsupport, particularly for subsistence farmers whoare more concerned with securing their basiclivelihoods than producing crops to sell. The realityis that both approaches play important roles. Thechallenge is to encourage more subsistence farmers

to move towards the market economy, throughreduction of risk to their basic livelihoods, so thatthey may be prepared to take the risks and rewardsthat the market offers.

If progress is to be made in smallholderdevelopment there is an urgent need to continuallyreview and update what is known and to put thisinformation before decision-makers in a way thatprovides them with the information to developcohesive strategies to support future development.

TECHNOLOGY – AT THE HEART OF IRRIGATION

It is well known and accepted that technology alonedoes not determine success and it is essential toassess its usefulness within a social and economiccontext for any intervention to have meaning. It isfor the individual farmer in each village, in eachcountry to assess the appropriateness of thetechnology within their own complex socio-economic circumstances. Technology provides auseful framework on which to build a strategy fordevelopment. Technology comes early in anyirrigation development and is always at the heart ofany irrigation scheme, large and small, and withoutit there is no irrigation scheme. Technology cansignificantly reduce the drudgery of lifting andapplying water and can help solve watermanagement problems faced by small-scale farmersmaking it easier and simpler to apply the rightamount of water to their crops at the right place atthe right time. The technology must be right for thesituation if irrigation is to have a chance of success.Putting in the wrong technology can mean that theseeds of failure are already well established beforea scheme has even had a chance to grow.

A wide range of well-established and well-documented traditional technology options isavailable for use by smallholders including waterharvesting, swamp irrigation, spate irrigation, floodplain irrigation using seasonal water and shallowaquifers, hill irrigation and groundwater irrigation.There is still, however, considerable room forimprovement and adaptation of these traditional

Technology provides a useful framework on whichto build a strategy for irrigation development. It isalways at the heart of any irrigation scheme.Without it there is no means of lifting or distributingwater


irrigation technologies so as to fit differentcircumstances.

In recent years there has been a growing interestin modern technologies. These usually cost muchmore than traditional methods and rely very muchon external specialist support from suppliers anddistributors. Small motor-driven pumps, forexample, can greatly reduce the drudgery of liftingwater. Distribution technologies such as trickle,sprinkle irrigation and piped supplies for the moretraditional surface methods, can help farmersmanage water better as well as reduce wastage,which in turn reduces the amount of water that needslifting. Modern technologies have gained favourwith farmers in the developed world allowing themto apply water more accurately and adequately andto increase yields and crop quality. Engineers andplanners often favour the use of these technologiesbecause water savings by some farmers means thatmore is available for others. As one irrigationspecialist stated; “Trickle irrigation can improvecrop yields, which is what farmers are interestedin, and significantly reduce water wastage, whichis what engineers are interested in”. A win-winsituation for people and the environment.

Low-cost technologies are being examined andevaluated. Most of the traditional technologies arelow-cost. However, the term ‘low-cost’ is usuallyreserved for modern technologies that have beendeveloped or modified to bring down the cost. Anexcellent example is the treadle pump, which wasdeveloped specially as a low-cost pump forsmallholders. It has been particularly successful inAsia in replacing the manual lifting and carrying ofwater. Its uptake in sub-Saharan Africa in recentyears is very encouraging.

Are these modern technologies as good as peoplesay, or are they just another quick fix promoted bythose who have a vested interest in selling theequipment? How successful have they been in thedeveloping world as opposed to the moresophisticated social and economic environments ofthe developed world? Are the traditionaltechnologies being ignored simply because it ispsychologically easier to invest in sprinkler andtrickle irrigation that are regarded as ‘efficient andmodern’ whereas traditional methods are regardedas ‘old and inefficient’?

THE NATURE OF SMALLHOLDER IRRIGATION

The term smallholder requires some clarificationas it means different things to different people. For

some, the large irrigation schemes in Egypt and theSudan are smallholder schemes. These schemes arelarge in terms of area but they are made up of manysmall farms (often less than 2 ha). They are designedand constructed by government agencies that thentake over the responsibility for managing the watersupply system. They are often described as formalor large-scale irrigation schemes and have borne thebrunt of much of the criticism of irrigationdevelopment in sub-Saharan Africa in the 1970s.Government management characterizes formalirrigation rather than size. For example, a 50 hairrigation scheme with 500 smallholders each with0.1 ha where the water supply is managed by agovernment agency might be thought of as asmallholder scheme. However, it would have all thecharacteristics of a ‘formal’ or ‘large’ irrigationscheme because of the way in which water and otherkey agricultural services are organizedindependently of the farmers.

For others, smallholder is synonymous with‘small-scale’ or ‘informal’ irrigation – small farms(often considerably less than 2 ha), privately ownedand under the complete control of the farmer withlittle or no input from external governmentresources. Such private farms have developed wherefarmers use their own initiative and respond eitherto their family’s food needs or to the market place.Farmers usually have direct access to surface wateror groundwater and make their own decisions abouthow and when they will irrigate and how much waterto apply. They practise a mix of commercial andsubsistence farming where the family provides themajority of the labour and the farm provides theprincipal source of income. This sector includessmall commercial enterprises growing high valuecrops such as cut flowers and produce for export.

Smallholders usually work on their own, but,because of the investment needed to gain access towater they sometimes need to work in groups. Anexample would be a scheme requiring a reservoiror a large pumping station on a river that one farmeralone could not afford. A 50 ha irrigation schemehaving 500 smallholders each with 0.1 ha managedby the farmers themselves without governmentsupport could equally be called a smallholderscheme. It would have quite different characteristicsto the similar sized scheme described above. Thefarmers themselves might manage such a schemeor commission a professional irrigation manager todo the job for them. The essential difference is thatmanagers are responsible to the farmers for theirperformance and should they fail to perform

Introduction4

properly the farmers have the ultimate power todismiss the manager and to hire an alternative. Thisis not usually the case when the government runsthe scheme.

The term smallholder is used in preference tosmall-scale as the latter is often confused with sizeas well as management style. Smallholder is also aterm now widely used by international agencies andincludes individual farms as well as groups wherethe farmers themselves or their representatives havetaken on the responsibility for managing thedistribution of water among the members of theirgroup.

The term irrigation needs clarification. Irrigationincludes any practice that stores, directs or exploitswater such as water harvesting, use of low-lyingwetlands and groundwater as well as the moretraditional techniques of diverting or lifting waterfor distribution using surface, sprinkle or trickleirrigation methods.


Some technologies are referred to as ‘traditional’because farmers have used them for many years, insome cases for centuries. Underhill (1984) firstsuggested a classification of traditional technologies,which is used here with some modifications, Table 1.

Brown et al. (1995) attempted to show how thesetechnologies were linked to farmer control, i.e. thelevel of control that a farmer would have over thedesign and investment decisions and over watermanagement, Figure 1.

Traditional technologies

Table 1. A physical classification of traditional smallholder irrigationClassification Description Some examplesWater harvesting Involves making better use of natural run-off.

Many approaches. Collecting run-off from acatchment and concentrating water in a smallercultivated area. Large schemes – several hectaresof catchment, small schemes may involveindividual plants. Success depends on having rightratio of catchment to cropped area.New developments applying chemicals, plastics tocatchment to increase run-off.

Ancient agricultural areas, Negev Desert,Israel. Pasture improvement by floodwater retention, Niger.Micro-catchments for fruit trees, Botswanarice cultivation, Gambia.

Swamp irrigation Fresh water swamps protected from salineseawater by bunds/dykes. Used for growing rice.Also tidal swamps planted after rains leach soil.

Gambia River, Gambia.

Inland valley swamps – small valleys (1–100 ha)where season/perennial streams can beused/controlled for paddy rice cultivation.

Sierra Leone, Burundi

Bolilands and dambos – depressions in swampgrasslands.

Rokel River, Sierra Leone, Guinea, Mali,Burkina Faso, Côte d’Ivoire, Ghana,Malawi and Zambia.

Lake swamps – large areas of flat plain flooded aslake level rises.

Lake Victoria, Tanzania

Spate irrigation Water spreading – spreading floodwater in riversand wadis across cultivated land in a controlledmanner.

Lower Omo Valley, Ethiopia, food andfodder crops

River flood plain irrigation

¶ Wet season Flooded lands. Usually rice grown in floodwaters.Many techniques.Controlled irrigation — controlling the rise infloodwater using dykes, canals and sluice gates.Used for both deep water and paddy rice.

Niger and Bani Rivers, Mali.

¶ Dry season Recessional irrigation. Impounding recedingfloodwaters with earth bunds.

Rice cultivation along most large rivers inWest Africa.

Residual moisture. Similar to recessional, water isstored in soil rather than on the surface.

Dry season cultivation of dambos or vleisin Malawi, Zambia, and Zimbabwe.

Pumped irrigation. Large areas of flood plainwhere surface water storage and shallow groundwater can be exploited using lifting devices, oftenfor vegetables.

Increasingly common in Nigeria also alongmost large river flood plains. River Omo,Ethiopia

Shadufs – traditional technique of lifting smallquantities of water using the ‘lever principle’.Usually low lift 1–2 m.

Most large river flood plains in West Africa,Niger, Bani Senegal, common along Nile.Tana River, Kenya.

Hill irrigation Land irrigated some distance from water source,supplied by canal or pipe. Source may be astream, small dam storage, gravity or pumped.

Traditional cultivation by the Chagga tribeon the slopes of Mount Kilimanjaro,Tanzania, Malawi, Ethiopia

Groundwater irrigation Involves exploitation of groundwater down to 15m. Exploited for small gardens, e.g. BurkinaFaso, Niger, Togo, Benin, Zimbabwe,Botswana

Traditional technologies6

WATER HARVESTING

Water harvesting is a method that has been aroundfor centuries but is not widely exploited in sub-Saharan Africa. It is ideally suited to arid and semi-arid areas where rain-fed crops cannot be grown withany certainty because the rainfall is both unreliableand highly variable (FAO 1994). The rainy seasonis often short with no assurance of when it will startand finish and there may be frequent long dry spells.Rainfall is collected from surrounding areas andchannelled as run-off onto farms to add to the rainthat falls directly onto the crops. Interestingly, noone doubts the critical importance of rainfall,although few policy-makers recognize theimportance of run-off, which is the inevitableproduct of excessive rain. It is a curious paradoxthat farmers recognize and exploit the naturalconcentration of rainwater in valley bottoms andlocal depressions, yet the overriding perceptiondriving policy is that run-off is a hazard. This viewis fuelled by the prominence given to the concernsabout soil erosion, which is one product of run-offand has been the focus of research and extension

efforts to curb it since the 1930s. Water harvestingrecognizes the potential value of run-off as aresource and aims to control the process in order tomitigate the hazard.

Run-off is collected from a large catchment areaand channelled to increase the water available in asmaller growing area. There are micro-catchmentsystems, which are modest in size, where water iscollected from land adjacent to the farm andchannelled directly onto the fields. On an evensmaller scale micro-catchments can be constructedaround individual plants (often trees). There aremacro-catchment systems that have large watercollecting areas. These are often a considerabledistance from the farming areas and can serve manyfarms. Substantial quantities of water can becollected from barren and fallow land andchannelled into the cropped fields.

In sub-Saharan Africa, although there areexamples of water harvesting, it occupies a neglectedmiddle ground between soil and water conservationand irrigated agriculture. Both these extremes havereceived far greater attention.

Figure 1: Farmer control of irrigation schemes (Brown et al. 1995)

WaterHarvesting Hill irrigation

Large scale Govt.(e.g. Gezira)

Groundwater

- deep wells Small StorageDams

SpateIrrigation

traditional

uncontrolled “improved”

state assisted

Groundwater

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farmer owned

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Farmer Control over Water Management

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Swamp irrigation

Swamps have been traditionally used for irrigationthroughout the region. In mangroves and coastalswamps earth banks or bunds are built to excludeseawater and allow fresh water from inland to enterthe cropped area, which is then planted with rice.The main areas for mangrove and coastal swampirrigation stretch from The Gambia round toLiberia.

Inland valley swamps are naturally occurringswampy valley bottoms (up to 100 ha) used to grow

rice. Small weirs and channels are constructed todivert natural drainage water around a swamp. Thearea is then divided into paddy fields, sluices areused to control the flow of water into the fields anda central drain allows excess water to escape backinto the natural drainage (FAO 1984). This is verycommon in the humid parts of West Africa such asSierra Leone and Liberia and in Burundi.

In the wet season many of the African lakes floodlarge areas of flat plains and these are used for ricecultivation. Examples of this type of irrigation existin Tanzania beside Lake Victoria and Lake Malawi,in Malawi by Lake Chilwa and in the countriesbordering Lake Chad. Also important are thetraditional irrigation practices found in bolilands anddambos. These are low, saucer-shaped depressionsin swamp grasslands such as those associated withthe Rokel River in Sierra Leone. There are similarareas in Burkina Faso, Ghana, Guinea, Côted’Ivoire, Mali, Malawi and Zambia.

Spate irrigation

This is a method of spreading water usually fromflash floods in wadis (FAO 1987), which is acommon practice in some arid countries such asSaudi Arabia and Yemen. It is not commonlypractised in sub-Saharan Africa, although there areinstances of its use in the Lower Omo Valley inEthiopia for both food and fodder crops. Thetechnology requirements need not be great thoughconsiderable skill is required to successfully divertand spread the water.

Flood plain irrigation

Flood plains are principally used for growing riceduring the wet season. There are a variety oftechniques involving different amounts of watercontrol that overlap to a greater or lesser degree.Some of the more distinct types of wet seasonirrigation include:• Deep-water rice grown on the flood plains of the

Niger and Bani rivers in Mali. Holdings are 1.5ha with earth dykes constructed to prevent thefields being flooded while the rice plants are stillimmature. Problems arise if the floods arrive toolate or too early or if they rise too fast andsubmerge the rice. Because of the high risk offailure, this technique tends to be secondary torainfed subsistence crops cultivated above floodplain level.

WATER HARVESTING IN TANZANIA

In Tanzania water harvesting is used successfullyon a large scale for growing rice (Hatibu 1999).Indian migrants are believed to have introducedthe so-called majaluba rainfed rice system in the1920s. It is used in the lowlands of Tanzania whereseasonal rainfall can be as much as 600-900 mmand runoff naturally collects in the valley bottomsmaking it ideal for paddy rice. Its adoption was notled by external change agents and was not fosteredby external subsidies, but nevertheless it hasspread steadily since the 1930s. Official data nowshow that the majaluba systems contribute 35percent of total rice production in Tanzania. Recentresearch has been carried out to try and introducemicro systems in the drier areas for maizeproduction. The idea is that micro systems wouldgive smallholders more control over their farms.However, when they were invited to evaluate themicro-catchment trials, farmers understood thebenefits of rainwater harvesting but were reluctantto adopt the system. They were more interested inthe greater potential of using macro-catchmentsystems and argued in favour of more ambitiousattempts to harvest runoff on a larger scale. So farthe limited trials with macro systems for maize aremixed. Proper control over distribution of harvestedrunoff within the cropped area is more problematicfor deficit-irrigated crops than is the case withmajaluba rice systems. There is also clear evidencethat failure to provide proper control over thedistribution of runoff can lead to serious erosion.Too much water can be as big a problem as toolittle. The need for cooperative group action canalso give rise to disputes over water sharing. Sowhether farmers will continue to prefer macro-systems to micro-systems as they acquire moreexperience in using them for maize productionremains to be seen.

However, one significant outcome of the researchis that government sees runoff as a benefit ratherthan just a hazard and the cause of soil erosion.Development of rainwater harvesting is to beincluded in the Tanzania National Water ResourcesManagement Policy.


• Flood irrigation involving the control offloodwaters to 50 mm/day for deep-water riceand 30 mm/day for paddy rice. Various levels oftechnology are possible from simple earth banksto dykes, canals and sluice gates.

In the dry season, shallow groundwater or openwater left after the floods is used through a varietyof gravity and water lifting techniques for:

• Recessional irrigation. Areas recently inundatedby floods are used by impounding the recedingwater with small earth bunds. This type ofirrigation is found in all the major flood plainsin West Africa for rice irrigation and close tolakes (e.g. Lake Chad) for growing maize andsorghum.

• Residual moisture. This is similar to recessionalirrigation but uses the water stored in the soilrather than water retained on the surface. It is avery common form of agriculture on all majorflood plains. In East Africa it is found on manysmall dambos or vleis (seasonally wet areas insmall catchments).

• Pumped irrigation. Pumping from rivers,streams and lakes is a simple activity and canusually be managed on an individual basis. Theadditional cost of pumping usually means thatfarmers are growing high value crops for sale inmarkets rather than low value subsistence crops.

The shallow depth aquifers that are scattered overmore than 100 000 ha of Niger as well as northernNigeria, Mali, and other Sahelian countries, alsoprovide possibilities for successful smallholderschemes. The aquifers must be rechargeable (as theyare in Niger and Nigeria). An obvious limitation tothe expansion of irrigation on this basis is the limitedarea where such aquifers exist, and the possibilityof overtaxing the recharging capacity of these areas.A wide variety of water lifting methods are usedcovering a range of traditional types such asarchimedian screws and the shaduf to the modernpetrol and diesel driven pumps. There has been agrowing interest in treadle pumps throughout sub-Saharan Africa since their introduction fromBangladesh and India (Kay and Brabben 2000).Generally motorized pumps are most common inthe richer countries that have ready access to spareparts and fuel, e.g. Nigeria. In water-scarce areasthere is also a growing interest in the use of moderndistribution equipment such as trickle and sprinkleirrigation for cash cropping.

Hill irrigation

There are many small, irrigated areas that aresituated some distance from their water source andsupplied by mainly open channels and low-pressurepipe systems. The water source may be a stream ora small dam supplying water by gravity or use ofsome type of simple lifting equipment. An individualfarmer or a group of farmers working together toshare the water resource can practise this type ofirrigation. Such systems are common in the hillyareas of central Ethiopia, Tanzania and Malawi.

Groundwater irrigation from medium to deepaquifers

Medium to deep aquifers (>30 m) can be exploitedall year and usually require more sophisticatedpumping than is commonly found in traditionallyirrigated areas. Usually submersible pumps drivenby electric motors or diesel engines are needed.There are numerous examples of this type of waterlifting and the agriculture based upon it throughout

INDIVIDUAL PUMP SCHEMES IN NIGERIA

Farmers in northern Nigeria lost their traditionaluse of the fadamas along the rivers following theconstruction of dams to control the river floods forurban water supply and irrigation. As an alternativethey turned to small-scale irrigation using shallowgroundwater recharged by the river and lifting itby shaduf or calabash in the dry season to growvegetables for local and city markets. In the early1970s a few farmers, with help from relatives,bought small pumps from private traders. In 1982-83 an agricultural development programme basedin Kano sold over 2 000 pumps for cash toindividuals or small farmer groups. Engineersintroduced low-cost well technologies from India,which reduced well construction by two thirds witha commensurate increased return on tubewellinvestment.

This has been one of the most successful irrigationdevelopments in Nigeria with many thousands ofpumps being used by private farmers.Maintenance is well established and so farmershave confidence in the technology. However,external monitoring was necessary to avoiddepletion of the aquifer.

Interestingly in the 1980s some farmers started togrow wheat on the fadamas in response to thehigh wheat prices in the country. A useful exampleof the way in which private farmers can and willrespond to the market if the price is right.


Africa and other parts of the world, notablyBangladesh, Pakistan and India. This type ofirrigation is only feasible for cash cropping becauseof the high cost of well construction and pumpingor when it is subsidized in some way.

COMMUNAL SCHEME EXPERIENCES

All the methods described above can be practisedby individual farmers on their own or by severalfarmers working together and sharing a commonwater supply. Once farmers group together themanagement of the supply system needs to be re-examined. If the scheme is small enough, the farmersmay choose to operate it themselves. As the sizeincreases a manager may need to be hired full timeto undertake management of the irrigation scheme.Either way there is a significant shift in themanagement of the irrigation from individuals whocan irrigate as and when they please to a group whomust work to an agreed schedule of sharing in termsof quantity and timing.

This communal approach is most favoured byaid agencies and national governments because it isseen as a way to help many farmers at the sametime. Agencies often step in, with the best ofintentions, to satisfy a need or to act as a catalyst fordevelopment. In so doing the aid agency orgovernment brings its own set of rules, which maynot be compatible with what is required on theground. Agencies need to disperse funds in line withtheir targets and are often constrained by time. Thetemptation to speed the process of development isalways present and, as a result, so is the risk of killingthe very thing that the agency is trying to foster bypouring in too much support too quickly. If thecommunity cannot absorb the funds fast enough anddo not have the institutional framework, farmers mayquickly lose any sense of ownership of the projectas they rely on a culture of handouts and supportfrom outside. In such situations the project has ahigh risk of failure. The challenge is to provide thecorrect amount of support over the right time periodto foster successful development. Underhill (privatecommunication) once said that if you ‘interfere’ ina privately initiated irrigation development byinjecting more than ten percent of the total cost thenyou are in danger of killing it. This is not an accuratefigure but it does give some order of magnitude ofwhat can be done.

There are many examples of communal schemesin sub-Saharan Africa ranging from the very large

(e.g. schemes in Nigeria, Kenya) to the moremodest (e.g. Senegal, Zimbabwe, Tanzania). Mosthave run into serious problems, although there aresome successes. They tend to be top-down inapproach and the technologies used are not alwaysconducive to simple water management practicesand often add to the problems of sharing availablewater resources rather than helping to solve them.

For example, open channels are the mostcommon system of supply and these are usuallyfitted with upstream control structures. This is oneof the most complicated systems of watermanagement available and so it is little wonder thatfarmers and scheme managers find it difficult todistribute water properly. There is no easy way ofknowing if too little or too much water has been putinto the canals without some sophisticated waterindenting procedures and flow measuring devices.The hydraulic structures can favour those at the topend of the canals and there is usually a constant needto adjust the control gates. In contrast, pipe supplysystems are much less common but are much simplerto operate and respond rapidly to changes in waterdemand. They can be less wasteful of water becauseit is easier to turn off a pipe supply when it is notneeded. It is not possible to turn off a canal withoutdraining it down.

When looking to the future it is vitally importantto review past experience of similar developmentsto see what lessons can be learned about what andwhat not to do. Several comprehensive reviews ofthe Sahel region have been made in recent years(e.g. Moris 1984 and 1987, Brown and Nooter1992). The two types of development are recognizedin the reviews: those in which farmers have fundedirrigation themselves using their own resources andthose that have received external support from anagency, either in the form of direct aid or through aspecial loan arrangement. The former are usuallybased on the farmers’ perceptions of family needsand those of the local markets. Investment is likelyto be made with great care to minimize the risk offailure. The latter have a much higher risk of failurefor a range of reasons, and the fact that they are forsmallholders (as opposed to large-scale irrigation)is no guarantee of success.

Review of the Sahel experience

Both Moris and Brown and Nooter’s studiesconcentrated on the Sahel region. The authors foundthat there were some strikingly successful privately


operated smallholder schemes in Mali, Mauritania,Niger and northern Nigeria as well as in BurkinaFaso, Chad and Senegal. In some cases, thesedevelopments were entirely spontaneous, and inothers, they were supported by NGOs or with

minimal government assistance. Some farmers tookadvantage of earlier investment and used theinfrastructure from earlier, failed large-scaleprojects. In some cases, expansion was facilitatedby the use of new low-cost construction techniquesthat reduced the cost of installing tubewells andhence the costs of irrigation.

The reasons for success varied from country tocountry and depended on a range of technical andsocio-economic circumstances. For example, inNiger private sector development had expanded welland responded to market forces. In Nigeria therewas a similar story but it had been helped along bysubsidised prices for equipment and farm inputs.Improved rural roads enabled farmers to market theirsurplus production and gain access to traders anddecentralized food-processing plants. Malidemonstrated the extremes of success and failure.Where there is success in the private smallholdersector and failure in public sector large-scaleirrigation. The Office du Niger, a parastatalcorporation, concentrated to such an extent on‘public services’ that it eventually had two staffmembers for every three farmers and for every 11ha of irrigation. Only 20 percent of farmers’ feeswent for actual inputs. Chad, although sufferingfrom civil strife for more than a decade, has seensuccess built on simple low-cost techniques fundedby non-governmental organizations.

Senegal exemplified the changing focus ofirrigation. This shifted from large, publicly managedirrigation systems with the farmer as labourer, tounsuccessful attempts to make parastatal irrigationagencies more efficient, to government assistedsmallholder irrigation, to experimenting with non-public sector irrigation. The early phases of thisexperience suffered from the inappropriateconstruction of irrigation perimeters and fromselecting crops that were not economically viable.Project design, operations and reform attempts byboth the Government and donors were carried outfrom the top-down, ensuring a low level of farmerenthusiasm. An attempt by the Government tostimulate smallholder irrigation failed when the plotsize determined by the Government was too smallto encourage farmer participation.

Successful projects in Burkina Faso have beenthe result of a relatively encouraging macro-economic framework. Farmers have often been ableto use the irrigation infrastructure from “failed”projects and the migration of men looking for workmade irrigation a profitable and necessary channelof agricultural development for women.

COMMUNAL IRRIGATION IN SENEGAL

Although communal schemes present a higher riskthan individual schemes there are examples wherethey work well. In Senegal small village schemesof 20 ha or less have been constructed along theSenegal River. These usually comprise 40–80plots of equal size supplied by an open channelsystem fed by 15 kW (20hp) engine pumps fromthe river.

It was important for farmers to find a way to stabilizerice production in areas where they no longer hadeasy access to the flood recession fields along theriverside. In most cases farmers all lived in thesame village and worked together on the commonobjective of solving the rice problem with irrigation.The farmers, who invested labour in clearing bushand digging canals, constructed the schemes inpart. They usually requested assistance from thelocal government irrigation agency and this usuallyresulted in the provision of a pump-set, pipes, sitesurvey and equipment for construction using fundsfrom aid donors. There was resistance to thisfarmer-initiated idea at first because of governmentplans for large-scale schemes in the area. Apresidential decree recognized the benefits oftechnical assistance for irrigation and theimportance of meeting farmer demands rather thanimposing a solution. Over the past 15 years at least700 schemes have been built.

Production has remained predominantlysubsistence oriented even though attempts weremade to extend irrigation to cash crops. Increasingfarmer holdings did not encourage farmers to growcash crops and they continued to grow rice in therainy season and maize for cattle food in the dryseason.

All infrastructure on the schemes is co-owned byfarmers. Rotation of water supplies is a recognizedway of sharing out the available supply. Repair andmaintenance is handled in the same way asconstruction. The elements that make theseschemes work well include:

• Construction through investment of labour byfarmers, albeit using donor-funded equipment.

• Selection of sites not usually used foragriculture.

• Pursuit of an economic objective – in this caserehabilitating a farming system under duress.

• Full autonomy for each village scheme –hydraulically, operationally and managerially.

(Diemer and Huibers 1996)


Cameroon has been an exception. Large-scaleirrigation has been successful but mainly becauseof strong expatriate management using farmers aslabourers rather than decision-maker. Farmers haveaccepted this situation because of the high financialreturns and because of the lack of otheropportunities.

From their comprehensive review, Brown andNooter (1992) suggested several characteristics thatare common to successful schemes:

• Technology is usually simple and low-cost (mostfrequently small pumps drawing water fromshallow aquifers or rivers and streams).

• The institutional arrangements are private andindividual.

• The supporting infrastructure permits access toinputs and to markets for the sale of surplusproduction.

• There is a high financial (cash) return to farmersat the times when they most need cash.

• Farmers are active and committed participantsin project design and implementation.

The authors found the perception of ‘success’was different for irrigation technicians, donors,governments and farmers. Their view was thatsuccess could only be assessed in terms of thefarmers’ definition.

The most effective arrangements for schemesthat were larger than individual ownership werefound to be (in decreasing order of success):extended family groups; private voluntary groups;water users’ associations and then cooperatives.They concluded that project design should be basedon the following concepts:

• Encourage smallholder, private and individualinvestment in irrigation and implement projectswith many small components, where NGOsfrequently are effective implementingintermediaries.

• Employ methods that ensure early and full farmerparticipation in project design and operations,devoting as much staffing and funding tostudying the farmers’ economic and socialsituation.

• Identify and disseminate low-cost small pumptechnology and tubewell construction techniquesand include provision of soil and water surveysbeyond the purview of individual farmers butessential for sustainable irrigation.

• Ensure a macro-economic framework that willreward the farmers’ and merchants’ desires for

low costs and high returns based on real costs.Both financial and economic rates of return mustbe satisfactory on a sustained basis and avoidunsustainable subsidies, since their removalcould lead to a project’s collapse.

• Ensure the availability of foreign exchangeneeded to secure supplies of spare parts, inputsand adequate repair facilities and ensure thatthere is the essential infrastructure needed foraccess to imports and markets.

• Make provision for training in maintenance andirrigation techniques for farmers, preferablythrough private sector suppliers; and ensure thatenvironmental considerations are provided for,such as the effect of irrigation on health, drainageand erosion control, which may not be evidentto the farmer.

ROLE OF TRADITIONAL TECHNOLOGIES IN SUB-SAHARAN AFRICA

A wide range of established and well-documentedtraditional technologies is available for use bysmallholders. These clearly play a significant rolein the region and will continue to do so. There isstill considerable room to adapt traditionaltechnologies to different circumstances, whichbecause of their low cost and simplicity can be usedand maintained by smallholders with little or noexternal support. They are particularly suited tosubsistence farming and equally have an importantrole to play in the transition to cash cropping. Forthis reason they have attracted much interest fromaid donors and governments wishing to supportsubsistence farming. Many lessons learned aboutwhat needs to be done have been concerned morewith the ways in which such technologies can beintroduced into farming systems rather than thetechnologies per se. However, there are stillconcerns about the technology and the ability ofpeople to design and construct good engineeringworks that will provide lasting service. There is alsoa danger that ‘low-cost’ solutions, which may beattractive to aid donors, may become a euphemismfor poor engineering.


Modern technologies

The term ‘modern technology’ in relation toirrigation usually refers to on-farm irrigation systemssuch as sprinkler and trickle irrigation. It can alsomean the introduction of piped distribution systemsfor surface irrigation as well as the use of treadlepumps (a recent innovation in Africa) or the use ofpetrol and diesel driven pumps in areas where suchtechnology is not normally used. Some professionalsand policy-makers perceive modern technologies asan intervention that can improve crop yields andquality and, at the same time, reduce water wastage(a better term to use than irrigation efficiency whichcan be misleading).

Most modern technology developments havebeen driven by the needs of the developed world toreduce labour inputs, keep energy costs as low aspossible and reduce water wastage, whilemaintaining operational reliability. In the irrigationsector it is the large commercial agriculturalenterprises that have driven such developments andthe results have been impressive. Production costshave fallen and crop yields and quality haveimproved.

Can similar benefits be realized by smallholdersin developing countries? Cornish (1998)summarizes the issues. He quotes Hillel (1989) whoexpressed concerns about the way in whichmanufacturers, and farmers as customers for theirproducts, in the developed world are fascinated bysophisticated technology and eager to have morespecialized and intricate hardware to use. He statesthat; “In the non-industrial countries, the importantattributes are, low-cost, simplicity of design andoperation, reliability, longevity, few manufacturedparts that must be imported, easy maintenance andlow energy requirements”. Hillel also suggests thatgenerally the ‘labour economy is less important.’Plusquellec et al. (1988) also argued that one of thedriving forces for sprinkle and trickle irrigationdevelopment has been the interest and investmenton the part of private sector manufacturers ofirrigation equipment. For the majority ofsmallholders in developing countries growing staplecrops with existing surface irrigation schemes andlow labour costs, returns can seldom justify thecapital expenditure associated with equipment.

Keller (1990) says that modern technology canresult in less water wastage because water isconveyed in pipes and irrigators can control theamount of water applied and its timing more easilywhich can increase productivity per unit of water.He suggests that traditional methods have limitedproductivity and are dependent on farmers’willingness to invest in land preparation and incoaxing water to spread evenly over the land. Buyingmodern irrigation equipment is trading money forlabour and skill. Keller also stresses that theopportunity cost of money for smallholders is veryhigh whilst that of labour and traditional skills islow. Farmers will make the investment in modernequipment only when the financial return is clearand relatively assured. For many poor farmers, theidea of a cash investment is inconceivable withoutcredit and institutional support that ensures success.Very few farmers in Europe and the USA survivewithout subsidies and financial support fromgovernments yet poor farmers in Africa are expectedto stand on their own feet with little or no support.

Modern technologies are unlikely to be taken upby poor subsistence farmers because they are mostlyconcerned with food security and minimizing risk.These technologies are more likely to be adoptedby farmers that have been able to diversify farmingincome beyond basic food crops and who are ableto consider marketing produce outside the home.The issue here is how to help farmers move into theincome-generating category through thedevelopment of a range of coping strategies.

How successful have these technologies been inthe developing world as opposed to the moresophisticated social and economic environments ofthe developed world? Are the traditionaltechnologies being ignored because it ispsychologically easier to invest in sprinkler andtrickle irrigation, which are perceived as ‘efficientand modern’, whereas surface irrigation is regardedas ‘old and inefficient’? Most important, are the newtechnologies, which are supposed to improveirrigation and reduce risk, only introducing newproblems that might expose farmers to a higher levelof risk than before?

Modern technologies14

Some useful sources of information includeCornish (1998) who provided a thorough review ofmodern technologies for smallholders in developingcountries. He points out that many moderntechnologies are not suited to smallholder irrigation.Cornish lists available technologies and identifiesfeatures making them suitable for use bysmallholders. Kay (1983) provides practical detailsof a wide range of sprinkle irrigation equipment andKeller and Bleisner (1990) describe both sprinkleand trickle irrigation systems in detail as well asproviding design examples. Kay and Brabben (2000)have recently published a review of the potentialfor the use of treadle pumps in Africa. Bentum andSmout (1994) produced a report, which reviews theuse of buried pipelines for surface irrigation and theirpotential to improve water management and reducewater wastage.

SPRINKLE IRRIGATION

Sprinkle irrigation is used on approximatelyfive percent of irrigated land throughout the world,the majority of which is in developed countries. Itis unlikely to replace the large areas under surfaceirrigation, (essentially the remaining 95 percent,except for a small amount of trickle). Sprinkleirrigation has a distinct advantage, because goodwater management practices are built into thetechnology. Sprinkle irrigation technology canprovide the flexibility and simplicity required forsuccessful operation, independent of the variable soiland topographic conditions. Pumps, pipes and on-farm equipment can all be carefully selected toproduce uniform irrigation at a controlled waterapplication rate and, provided simple operatingprocedures are followed, the irrigation managementskills required of the operator are minimal. This putsthe responsibility for successful irrigation in thehands of the designer rather than leaving it entirelyto the farmer. Sprinkle can be much simpler tooperate and requires fewer water management skills.However, it requires sophisticated design skills andon-farm support in terms of maintenance and thesupply of spare parts.

Sprinkle is potentially less wasteful of water anduses less labour than surface irrigation. It can beadapted more easily to sandy soils subject to erosionon undulating ground, which may be costly to re-grade for surface methods. There are many types ofsprinkle systems available to suit a wide variety ofoperating conditions. The most common forsmallholders is a system using portable pipes

(aluminium or plastic) supplying small rotary impactsprinklers. Because of the portability of sprinklesystems they are ideal for supplementary as well astotal irrigation.

At the forefront of sprinkle developments is thecentre pivot machine, which can irrigate up to l00 haat a time. These machines are very adaptable. In theUnited Kingdom they have been used on small andirregular shaped fields crossing field boundaries toirrigate several fields growing different crops at thesame time. One machine was used to irrigate severalfarms where the farmers decided to cooperate. Herethe farmers’ role in irrigating large areas havingmultiple ownership and minimal inputs should notbe underestimated. Libya is a well-known exampleof their use for irrigating large desert areas. As faras the farmers under the pivots were concerned itrained once a week as the pivot rotated. From amanagement point of view sprinkle irrigationprovided a relatively simple system to operate andallowed farmers to do the farming. Although theskills needed to operate these machines and tomaintain them must not be underestimated, they areno more than those required to keep motorcarsrunning. In most developing countries techniciansdo this very successfully in the private sectors. Thisis not so much to advocate the widespread use ofcentre pivot machines for smallholders but to pointout that technology can be very adaptable and canbe used in innovative ways when the conditions areright.

Table 2 provides a summary of the differentsprinkle systems available.

Sprinkle for smallholders?

Sprinkle irrigation was mainly developed for largerfarms. The system is not very flexible and adaptableto the multitude of small plots usually found on smallfarms. In some cases there are ways around theproblem, such as using the same equipment inimaginative ways as can be seen in the followingsection, which is based on experience gained inZimbabwe. New ideas are being developed forequipment specifically suited for use by the smallfarmer both in terms of technology and cost.

Cornish (1998) lists several countries wheresprinkle irrigation has been used to supportsmallholder development in countries outside of sub-Saharan Africa such as Jordan, Israel, Cyprus andothers. The problem is that most reports do notusually answer such important questions as whopays for the equipment, who owns and runs the


schemes and just how successful they have been inmeeting users aspirations?

Zimbabwe experience

Zimbabwe is special when it comes to irrigationequipment because it has a history of largecommercial farming (200 ha and more) on which asprinkle and trickle irrigation manufacturing,distributing and support network has grown.Zimbabwe also has a large smallholder farmingcommunity and attempts have been made to adaptthese same systems to their needs. Satisfying onelarge farm having a single crop is rather differentfrom satisfying 200 farmers on the same land areagrowing many different crops at different times. Thetechnical problems of adaptation can beconsiderable. Diemer (2000) looked at a sprinklescheme where the layout normally used for largecommercial farms was transferred without changeto the smallholder situation. It created endlessmanagement problems that were eventually solvedby re-arranging the same equipment in a differentlayout. By using flexible hoses to supply water tosprinklers rather than the rigid aluminium pipelayout, this system was found to be much moreadaptable to the needs of smallholders.

The government irrigation design andconstruction service, Agritex, has been at theforefront of developing new schemes forsmallholders. A recent, comprehensive study (FAO2000) of ten smallholder schemes (six sprinkler andfour surface) has highlighted some of the successesand failures. The schemes are all typical smallholderdevelopments that were initiated and financed by a

government agency to stimulate development. Allhave several farmers sharing the same water sourceand distribution system. All have been handed overto the farmers for them to operate and maintain. Twoexamples, a success and a failure, are highlightedin the box Chitora, Zimbabwe – a success; NgeziMamina, Zimbabwe – a failure.

Except in one or two cases where there wasreference to poor design of layouts and equipment,the technology used was not a major determinant inthe success or failure of the schemes, although itmay have played a role. Sprinklers can simplifyirrigation management and although it was notdiscussed, the long history of sprinkle irrigation inthe country is likely to have created confidenceamong farmers that the technology would work welland if not then it would not be difficult to get it fixed.

What is clear from the study are the complexsocial, economic, technical and institutional issuessurrounding smallholder irrigation schemes makingeach one unique and demonstrating the importanceof getting the mixture right. It also emphasizes thepoint made by others that small-scale does not meansimple.

The FAO study has some general conclusions:

• It is essential for farmers to truly participatethroughout the project planning, implementationand evaluation phases and be treated as “owners”and not just beneficiaries of projects.

• Consultants engaged to implement such schemesshould have experience in participatory ruralappraisal and smallholder irrigationdevelopment.

• Only projects that are technically sound shouldbe handed over to farmers.

Table 2. Summary of sprinkle irrigation systemsSystem Use

Conventional systems Portable Hand-move

Roll move

Tow line

Uses small rotary impact sprinklers

Widely used on all field and orchard crops

Labour intensive

Semi permanent Sprinkler hop

Pipe grid

Hose pull

Similar to portable. Lower labour input but highercapital cost

Mobile gun systems Hose pull

Hose drag

Large gun sprinklers that can be replaced by boom.Good for supplementary irrigation

Mobile lateral systems Centre pivot

Linear move

Large automatic systems. Ideal for large farms with lowlabour availability

Spray lines Stationary

Oscillating

Rotating

Fixed spray nozzles. Suitable for small gardens andorchards


• It is important to help farmers with inputs forthe first season so that they can build a cash baseto ease cash flow.

• Farmer managed irrigation schemes can reducethe financial burden on the government in termsof operation and maintenance.

• Government needs to produce a clear andsystematic strategy for handing over governmentmanaged schemes to farmers.

• The issue of inheritance as it affects land tenureshould be decided in the planning andmanagement of smallholder irrigation schemes.

One interesting fact, which is not raised by otherinvestigators, is the age profile of the farmers onthe Chitora irrigation scheme. It is well recognized

throughout the world that younger people tend tobe more receptive to new ideas, particularly to newtechnology, and may also be in a position to takegreater risks than their elders who have more familyresponsibilities. Targeting young farmers may beone strategy that is worthy of further attention.

South Africa experience

An interesting development has been underwaysince 1981 using large mobile irrigation machinesas part of the Taung project in South Africa. Centrepivots and linear move machines were installed withthe aim of providing income and livelihoods forsmallholders on farms varying in size up to 10 ha,

CHITORA, ZIMBABWE – A SUCCESS

This is a small scheme irrigating only 9 ha with drag-hose sprinklers. It is one of the most successful farmer-managed irrigation schemes in the country. In operation since 1994, it is run by young people aged 22 to 27years who were without jobs and were dependent on their parents for everything. The parents felt they weretoo old to engage in irrigated agriculture and so 18 of their children accepted the offer of irrigation support fromAgritex, the government irrigation development agency. Agritex provided all the inputs for the scheme includingthose for the first growing season. From then on the young farmers had to finance the scheme themselves.They were involved at every stage of development from planning to implementation and now have fullresponsibility for operation and maintenance.

The cropping programme is essentially for high value horticultural crops grown for the markets on the outskirtsof Harare where there is a demand for good quality vegetables. Grain maize is not grown because farmersargue that it is cheaper to buy it elsewhere than to produce it themselves. The argument is based on theprinciple of opportunity cost.

Farmers’ income averages Z$60 000 per year compared with that of Z$16 800 for unskilled labour wages inthe town. The farmers see no reason to migrate into the towns where they are well aware that their costs ofliving would be much higher.

The scheme is entirely farmer-managed through a system of bye-laws enforced by an Irrigation ManagementCommittee that is responsible for coordinating all scheme activities including payment of bills for electricity,maintenance work, monthly subscriptions from farmers, maintaining discipline in the scheme and reallocatingplots.

The farmers continue to receive support from Agritex in the form of training and extension services. Thesuccessful performance of the scheme is reportedly a result of the farmers’ sense of ownership and their beliefthat the scheme belongs to them. It is not possible to say what role technology played in this success. Undoubtedlywater management was made easier to deal with and the availability of spare parts and technical support inZimbabwe must add to the security of farmers using such systems.

NGEZI MAMINA, ZIMBABWE – A FAILURE

This is a communal scheme built at the same time as Chitora but on a larger scale as part of an aid projectassociated with dam construction. It is typical of a government built and run irrigation scheme that has run intodifficulties in getting farmers to ‘own’ the scheme originally constructed for their benefit. The scheme covers216 ha with 154 plots ranging from 0.5 to 1.5 ha. Irrigation is by sprinklers fed by gravity therefore avoiding theproblems of pumping. Low value crops are grown with very few high value vegetables. Since its inception in1994 the scheme has not run well. Farmers claimed they were never consulted about the scheme and wereafraid they would lose their land. It continues to be run by the Government, which also pays for electricity, waterand services. This leads to scant regard for the use of water and electricity by the farmers. Farmers arereluctant to take over the responsibility of running and maintaining the scheme themselves and complain thatthe infield designs are inadequate, which leads to regular disputes between the farmers and governmentinstitutions.


cropping wheat, barley, corn, peanuts and cotton(Valmont personal communication). The project,which was originally installed to settle farmers inthe former ‘homelands’, so far has 73 pivots installedeach irrigating 40 ha. The operation and maintenanceservices are all contracted out to an independentcontractor whose role is to keep the irrigation systemrunning. Government supports the farmers througha full range of extension services. The installationcosts were estimated to be around US$1 000/ha.Unfortunately there is very little informationavailable about how successful and sustainable thiskind of development can be. There are worryingsigns that the approach may be too ‘top-down’.

TRICKLE IRRIGATION

Trickle or drip irrigation comprises a system of pipesand emitters that can deliver small frequentirrigations to individual plants. This technology can

provide farmers with a method of precise controlover the timing and amount of irrigation and so theycan easily meet the crop water demand withoutwasting water. Wastage can only occur if the systemis left running for too long or there are leaks in thepipes.

Trickle irrigation is not yet widely used on aworld scale, and covers less than 0.1 percent ofirrigated land. Even in Israel, where much of theearly research and development was done and wateris very scarce, trickle has not flourished as much asmight be thought. Sprinkle irrigation still providesmore than 70 percent of Israel’s irrigation becausethis is still considered to be a most efficient methodof irrigation and one that is financially viable.

Claims made about crop yields and water savingneed to be judged with care. Sales people often implythere is something magic about trickle irrigationwhen they refer to substantial increases in yield andsavings in water use. There is no magic. Cropsrespond primarily to water and not so much to themethod of application. They need the same amountof water to grow properly whether this is appliedwith trickle irrigation or with surface floodingmethods. If the right amount of water is applied tothe crop at the right time it will flourish. Similarly,water savings can only be made by reducing wastageand not by reducing the amount of water the cropneeds. Ironically many farmers end up applyingmore water when using trickle irrigation becausethe system allows them to apply water more easilythan with other methods.

A major technical problem with trickle irrigationis emitter and lateral blockage from sand and silt,chemical precipitation from groundwater and algaefrom surface water. Each of the problems takes theuse of trickle into a level of technology and supportthat can be difficult to sustain in a developingcountry. On a small scale the farmer can simply goaround and clean the system regularly, which canovercome these problems but on a larger scale thiswould not be practicable.

However, there are conditions that make thismethod of irrigation a very attractive option. It isideally suited to areas where water is scarce orexpensive, where water may be saline, where labourcosts are high and where soils are poor. An importantadvantage is the ease with which nutrients can beapplied with the irrigation water. This is much moredifficult to do with other irrigation methods.

A distinct advantage of trickle for smallholdersis the way in which it can be adapted to small andvaried plots of land. This is how trickle is being used

EXPERIENCE FROM OUTSIDE THE REGION

Mexico has a history of irrigated agriculture havingover 6 million ha under irrigation (Manuel andMaldonado 1999). Sprinkle irrigation has long beenused to support smallholder irrigation developmenton a large scale and in particular by FIRCO (TrustFund for Shared Risk) which is part of theSecretariat of Agriculture, Livestock, and RuralDevelopment of the Government of Mexico.

A recent development was undertaken in a hillyregion of the country. During the three years ofthis programme it was reported that 1 000 sprinklerirrigation modules (each of 0.1 ha) were installedin 60 communities belonging to 35 differentmunicipalities. The reason given for usingsprinklers and trickle was water scarcity and theproblems related to using more traditional methodsof irrigation. The cost of materials was US$500/ha. Installation costs were borne by the farmerswho contributed their labour and governmentengineers provided technical assistance. The maincrops grown included corn and beans mainly forself-consumption as both staple crops areexpensive for isolated communities who are distantfrom markets. Farmers were reported to be seekingto change their cropping pattern to satisfy both theirhome needs and to grow vegetables for the citymarkets.

Although there were no indications of the extentof farmer funding and involvement in the scheme,Mexico has a well-developed irrigation sector andit is likely that this scheme will build on this tradition.Whether it is ultimately successful remains to beseen.


in India where farmers have gone from surfaceirrigation to trickle and have bypassed sprinklebecause it is considered an inflexible system for useon small plots. Local manufacture of trickle partshas encouraged Indian farmers to take up the methodwhere they are assured of spare parts.

A further advantage of trickle is the ease withwhich it can be operated. It is a pipe system and socan be switched on and off easily. The potential formaking timely and adequate irrigations as well asfor reducing water wastage is good. The challengeis to realize that potential.

Trickle for smallholders?

A critical issue for smallholders is the cost of trickleirrigation. It does tend to require a larger capitaloutlay than most other methods of irrigation. Thecost may well be justified by improved cropproduction and hence financial returns for farmers.The high initial cost is a result of the set nature ofthe system, its reliance on precision-engineeredcomponents and need for water filtration, all ofwhich can be expensive.

The cost of a trickle system is determined by croptype, row spacing and the total field area irrigated.System costs can range from US$1 000–3 000 perha (Cornish 1998). In addition the systems requireskilled management for effective operation andmaintenance – filters require regular cleaning,systems may require periodic flushing to preventbuild-up of slime. Equipment must be regularlyinspected to identify and replace damagedcomponents. The combination of high cost anddemanding technical management means that

conventional trickle technologies are normallyconsidered to be inappropriate for resource poor,smallholder farmers.

Trickle experience from outside the region

Little has been reported on the use of trickleirrigation in sub-Saharan Africa. There is, however,a growing experience of its use in other developingcountries. In India, trickle irrigation has beenintroduced for high value crops (vegetables, flowers,spices) in some of the more arid parts of the countrywhere water is scarce. In 1993 it was reported (Singhet al) that over 50 000 ha were being irrigated bytrickle irrigation, this has now risen to over 225 000ha. This substantial increase in the use of tricklemethods is not so much a result of market demandbut the low-cost of the systems, which are heavilysubsidized by the Indian Government. Over the pastten years more than 100 companies have been setup to produce trickle equipment. Claims of watersavings as high as 30-60 percent and yield increasesof 20-40 percent have been made. Success was,however, masked by heavy subsidies. Even withsubsidies the systems were too expensive for mostsmall farmers. Trickle systems were also thought tobe too complicated to operate and maintain and noteasily divisible to fit small plots (Polak andSivanappan 1998).

IMPROVING TRADITIONAL METHODS

Most smallholders in sub-Saharan Africa use surfaceirrigation methods and distribute water using openchannels. When several smallholders use the samewater source and distribution system there aregreater risks of failure. The result all too often ispoor water distribution and unreliable andinadequate water supplies to the field.

Most smallholder irrigation schemes use openchannels to supply water because they areconsidered cheap and simple to use. In reality, froma management point of view, this type of irrigationis the most complex and inflexible of supplysystems. Open channels can only be used for fixedschedules, flows are often unreliable and inadequateand distribution between the various canals is oftendifficult to manage. Even the choice of gates (weirsand sluices) for discharge and water level controlcan exacerbate the problems leading to the classic“top-end versus tail-end” problems of waterdistribution along canals.

FARMERS SOLVE THEIR OWN PROBLEMS IN GHANA

A small-scale irrigation project was establishedon the outskirts of Khumasi for a group of womengrowing vegetables for the local markets. Thescheme uses open irrigation channels supplyingmany plots, less than 0.1 ha each owned by adifferent person. The scheme was designed andbuilt to supply water on a rotational basis and eachwoman was given an allotted time when she wouldreceive water. The women objected to the schemeand said that the rotation was unworkable becausethey had lots of other household and family dutiesthat took priority over irrigation. They solved theproblem themselves by building small storagetanks on their farms. This allowed them to receivewater when it was available and to irrigate theircrops when it was convenient to them.


Canal management can be simplified through useof relatively simple technologies, such as fixedregulators (e.g. solid weirs), or by building smallstorage reservoirs along the canals or replacingcanals with pipes.

Storage reservoirs

Constructing small storage reservoirs along a canalsystem or on farms means farmers can take wateras and when they need it and suppliers can supplyas and when it is convenient to them. The reservoirswork in very much the same way as domestic waterstorage. The simplest example of this is waterstorage in dams, where water is held back in timesof flood for use in the drier seasons. Storing waterunderground is much the same idea. The groundconveniently holds the water so that it is availablefor pumping when the farmer chooses to irrigate.

Storage in the supply system itself has beenwidely exploited in the Sudan and in schemes innorthern Nigeria. This is usually storage over a shortperiod of 24 hours. Although it adds to the cost of ascheme the benefits in terms of reduced waterwastage can be significant.

Buried pipelines

Burying pipelines to replace canals offers anopportunity to simplify water management andreduce wastage (Bentum and Smout 1994). Theyuse examples in Bangladesh for much of theirconclusions on the benefits of pipe systems. Similarbenefits were reported in India (Campbell 1984) andin Sri Lanka (Merriam 1987). Merriam has alwaysargued that buried pipe distribution systems forsurface irrigation represent an intermediate solutionbetween lower-cost earthen channels and the moreexpensive sprinkle and trickle systems.

Benefits include:

• Systems become demand rather than supplyoriented when pipes are used. Pipe systemsrespond rapidly to changes in water demand.

• There is reduced wastage, greater flexibility andreliability of supply.

• Short water transit times enable water to bemoved around a command area more rapidly thanwith channels.

• Less land is taken up with the irrigation system.

Pipe systems are generally thought to beexpensive. This term is relative in terms of thesavings made in land and water. The simplificationof management practices means that the additionalcost may well be justified. However, there is littleevidence of these systems being used in sub-SaharanAfrica.

A ROLE FOR MODERN TECHNOLOGIES IN SUB-SAHARAN

AFRICA?

Modern technologies undoubtedly have the potentialto raise the productivity of water and labour.Technically, they are best suited to conditions wherewater is scarce and the opportunity costs of labourare high. Modern technologies have yet to beseriously tested and evaluated in the region. Thereis also concern that their introduction intodeveloping countries is driven more by commercialinterests rather than need. This can lead toinappropriate use.

Experiences in Zimbabwe are of particularinterest. Success in this country is clearly linked tothe long history of sprinkle irrigation and supportthroughout the country by the private sector. Thesuccess of the small Chitora scheme, Zimbabwe,may be due in part to young people who are willingto accept new methods of working. This may be animportant point to be borne in mind by developerswhen persuading farmers to change or take upmodern systems.

What is clear is that modern systems are onlyaccessible to farmers who can afford to buy themand who are growing cash crops such as vegetables,fruits and flowers providing sufficient returns to payfor the investment. Farmers will make theinvestment in modern equipment only when thefinancial return is clear and relatively assured.Modern systems have little to offer poor subsistencefarmers and so are unlikely to be taken up by them.


Low-cost technologies

A NEW PHILOSOPHY

If the investment costs and the inherent risks ofconventional trickle and sprinkle irrigation are toohigh for most smallholders, are there any low-costalternatives? Most of the innovations in this directionhave been in trickle and to some extent sprinkleirrigation. India, Nepal and China stand out ascountries that have sought to promote the use of low-cost systems by smallholders. These countries haveestablished national manufacturing capacity andplaced emphasis on ‘simple’ systems that do not relyon automatic control or other labour-saving devices.

Low-cost systems attempt to retain the benefitsof conventional systems whilst removing the factorspreventing their uptake by poor smallholders:purchase cost, the requirement of a pressurizedsupply, the associated pumping costs and complexityof operation and maintenance.

Low-cost systems are not widely reported in theliterature, although this could be a consequence ofthe nature of the organizations and agencies involvedin their development and promotion, which aremainly development NGOs, rather than a reflectionof their potential value for smallholders. Someequipment has been developed and tested by NGOsand church affiliated groups but such centres areoften not well resourced to engage in wide-scaleproduction and marketing of their products.

IRRIGATION KITS

Several low-cost trickle technologies and somesprinkle systems have been developed, which arenow in use in several countries. In most cases theseare aimed at improving distribution and applicationof water. Attempts have been made to make themas simple as possible so that they can bemanufactured at lower cost and operated andmaintained easily. Systems are usually sold in kitform for relatively small areas of land (e.g. 25 m2).This too helps to keep the cost down and the idea isthat farmers can add to the kits as they receive cashfrom the increased profits on their crops. Thisincremental development is not easily accomplishedwith normal commercial systems, particularly when

pumps are needed to pressurize the systems. Low-cost can mean low initial capital outlay rather thanlow-cost per hectare. Some recent innovations aregiven in the following sections.

Bucket kits (developed by Chapin)

These are manufactured by Chapin Watermatics,USA. Each kit supplies water to two 15 m lateralslaid on a 1 m raised bed, cropping just 15 m2.

Chapin estimates that his company has donated15 000 – 20 000 bucket kits to different programmesin Africa. These kits are given to the projects andsold to the users for US$7. When the cost is workedout for a hectare it comes to US$4 660/ha, which isnot so low. However, it is the low incremental costthat enables farmers to begin using this system. EvenUS$7 per kit is a subsidized price and it is arguedthat this is not sustainable development. Equipmentis imported and distributed at this price by missionstations and aid programmes. USAID has alreadyfunded the distribution of Chapin’s kits and KARI(Kenya Agricultural Research Authority) isevaluating the equipment. Chapin has also promotedlarger one-quarter acre (0.1 ha) kits whichInternational Development Enterprises replicateswith its low-cost, locally manufactured kits.

Wagon wheels

The ‘wagon wheel’ systems are found in WesternCape, South Africa. They comprise a central watertank with laterals radiating as spokes to a length ofabout 5 m. Each wheel irrigates a circle of about8 m2.

Irrigation kits (developed by IDE)

International Development Enterprises (IDE) is aninternational NGO that first started to develop low-cost irrigation kits in India and Nepal in 1995. Fieldtests are now being conducted in Sri Lanka,Bangladesh, and Viet Nam.

Various kits have been produced to meetdifferent circumstances:

Low-cost technologies22

• Bucket kits. These are for home gardens andwere based on the Chapin Bucket System andcost approximately US$5. Each comprises a20 litre household bucket installed on a pole atshoulder height. The bucket is fitted with a 10 mlateral line and is filled two to four times a day.The single lateral line has 26 micro-tubesattached and each waters four vegetable plants,irrigating 50 m2, enough to provide vegetablesfor a family.

• Drum kits use a 200-litre drum made of steel orplastic and costs around US$25 and irrigates a125 m2 plot. Water is supplied through a simplefilter and supplies five 10 m-laterals each fittedwith 26 micro-tubes.

• Micro sprinkler kits are suitable for farmerswith access to a pressurized water supply. Eachcomprises 15 micro sprinklers with laterals andcan irrigate up to 250 m2 at a cost of US$25. It iswell suited to a small garden growing a range ofvegetables.

• Overhead sprinkler kits comprise twosprinklers on tripods with pipes and rely on theavailability of a pressurized water supply, e.g. adomestic 0.4 kW (0.5 hp) pump. The cost isUS$30, with the pump it is estimated to costUS$120. It is well suited to field crops such aswheat, green gram and soybeans.

The kits were all designed to be incremental,allowing farmers to start with a small kit and thenexpand by investing profits derived from the cropsales. The divisibility of the systems as a means ofreducing the initial and subsequent capitalinvestment is a vital part of making such systemsavailable to poor farmers who cannot affordsignificant capital expenditure. Laterals are designedto be moved, which can significantly reduce theamount of equipment needed.

In Nepal, a typical trickle user has invested aboutUS$26 for the trickle system, US$15 for otherinputs, uses family labour (idle in the off-season),and increases his/her income from cash croppingfrom around $10 to around $100 (per capita GNP inNepal is around $200).

IDE typically works with two types of farmers:those who are already growing commercial crops,and subsistence farmers. In most cases, thecommercial farmers are able to take immediateadvantage of the system benefits. Subsistencefarmers can benefit through the possibility of havingtheir resources go further and gaining access to acash economy. The extent to which this is asuccessful strategy is not known.

IDE fully recognize that coming up with anappropriate technology is a small part of the solution.Focus is on reducing costs by using locally availablematerials, involving local manufacturers and dealersand placing emphasis on sustained marketing anddemonstration so that the manufacture and supplyof the equipment is commercially attractive.

IDE has developed a highly effective strategyfor mass marketing of low-cost income-generatingtechnologies in developing countries.

The basis of this is that:• technology must be affordable to the farmer and

must have a very high return on investment overthe short term;

• manufacturing should be done locally by private,non-profit entities;

• a dealership network should be developed withthe manufacturers that can deliver goods toremote areas of the country for a reasonableprofit;

• local expertise in installation and repair needs tobe developed through training;

• a massive public information campaign needs tobe conducted to stimulate demand for the productup to a sustainable level.

By following this strategy, a sustainable deliveryinfrastructure can be put in place. Demand for thetechnologies has a chance of increasing togetherwith income that can support this infrastructure.

Using this strategy IDE has already had a greatdeal of success with the marketing of treadle pumpsin Africa. The intention now seems to be to promotethe same model for low-cost irrigation systems.

Family kits (developed by Netafim)

Netafim, an Israeli trickle irrigation manufacturer,has developed what it calls the Family Drip Systemthat can be adapted to variable plot sizes. This wasdeveloped in China and comprises their standardemitters, pipes and filter equipment. The kit worksat low head and is pressurized from a tank ratherthan by pumping. It has the appearance of a large-scale system that has been scaled down for use bysmallholders rather than a system that has beendesigned specially for this market.

The costs of the system range from US$150–240 for 1 000 m2 (US$1 500–2 400 per ha). Havingintroduced these systems in China, Netafim plansto replicate this experience in 50 other countries.There is as yet little evidence of how successful thesesystems are for smallholders.


West Africa experience

An FAO/Japanese funded programme isinvestigating the potential for smallholder irrigationusing a combination of surface irrigation methodsand water distribution using pipes (FAO 2000). Awide range of ideas is under evaluation at a trainingschool in Ouagadougou, Burkina Faso, whichincludes the use of low head tanks, simple drippersfor applying water and the use of hose pipes. Theintention is to find suitable systems that help toreduce water wastage in water short areas, andwhich at the same time are low in cost and simpleto use. Local materials such as PVC piping is beingused with simple connections so that componentscan be resourced locally rather than relying onimported materials. The tests are still at an earlystage and it will be some time before they are testedand evaluated in the field.

Many other examples of various technologiesbeing adapted for use by smallholders are listed inthe report of a workshop organized in Ouagadougouby IPTRID and FAO in 1998.

Some common characteristics of low-costsystems

Low-cost systems have several characteristics incommon:• These systems are designed specifically for small

plots, which can be added to as and when thefarmer chooses. Low-cost systems are aimedspecifically at smallholders. They are usually inkit form for small plots from just 15 m2 up to1 000 to 2 000 m2.

• They use low pressure (or head). Loweringpressure reduces the energy needed to lift thewater and lessens the burden on farmers,particularly if the water is lifted by hand.

Whereas commercial systems operate around10 m head, low-cost systems usually workaround 2–4 m head. A raised bucket, oil drumor other storage tank may provide enoughpressure and could be filled manually. Lowoperating heads means that any head loss alongthe lateral is a larger percentage of the totaloperating pressure and has a direct effect onemitter flow rates. This can be overcome to someextent by keeping laterals short.

• Some irrigation precision is lost. Operating atlow pressure can mean a loss of irrigationprecision. This can also happen using low-costemitters. Many manufacturers have chosen to usesimple emitters, such as orifices or holes punchedinto the lateral. It is not always possible to formthe holes accurately. The result can be largevariations in discharge along a lateral as a resultof different sized holes. Changes in pressurealong a lateral exacerbate this problem. Somemanufacturers supply their normal emitters (e.g.Chapin’s bucket kit) that tend to be more costly.This can increase the cost of the system becausethe emitters are built into the pipe wall and anymanual cleaning of clogged emitters is notpossible.

• Precise irrigation may not be as important tosmallholders as it is to farmers in the developedworld. This depends on how much precision islost and it may well be that low-cost systems,although not perfect, are far better at applyingwater than the other methods used by farmers.The farmer’s ability to manage the irrigationapplication properly is more important thanworrying about some of the system’s technicalshortcomings.

• They use simple filtration. Clogging of the verysmall flow paths in the individual emitters is thesingle greatest problem of any trickle system. Tominimize this risk, conventional trickle systemsrely on a primary fine wire-mesh filter and insome cases (depending on water source)additional filtration through a sand medium isnecessary. The filters are a high-cost item. Theyrequire careful routine maintenance and imposea head loss, and therefore need additional energyinput.

• Low-cost systems use simple cloth or wire-meshfilters to prevent large particles entering laterals.In addition the systems using simple holes in thelateral rely on the farmer using a pin or fine wireto clear any emitter that becomes blocked. Thisis practicable on a farm of 0.1 ha, which may

SOME EARLY EXPERIENCES

Technical studies were reported by Miller andTillson (1989) in Sri Lanka and Batchelor et al.(1993) in Zimbabwe on the use of low-cost tricklesystems for smallholders. In both cases thesystems evaluated relied on imported, high-cost,commercial trickle tapes although both systemswere low head and had very simple filtration.Batchelor et al conclude that even with thesesimplifications the equipment was too expensiveand difficult to obtain. Neither study led on toprogrammes of wide-scale promotion or adoption.

Low-cost technologies24

have 2 500 emitters to maintain, but would beunrealistic on larger systems. Cleaning by handis not possible on most commercial trickle tapebecause of the way it is manufactured.

• Movable laterals are often used. Sometechnologies reduce the cost of equipmentthrough use of a single lateral to irrigate ten rowcrops, the lateral being moved by hand betweeneach row. IDE uses this idea to reduce costsalthough early Israeli use of trickle systems usedthe same approach.

TREADLE PUMPS

Over the past decade, a small, but significantrevolution has been taking place in smallholderirrigation in the developing world with theintroduction of the treadle pump. This simple,human-powered device can be manufactured andmaintained at low-cost in rural workshops indeveloping countries. Acceptance of these pumpsin Bangladesh, where it was first developed in theearly eighties, has been described as extraordinary.Over 1.3 million pumps are now in daily use in thatcountry. Farmers have spent US$40 million ontreadle pumps at approximately US$35 each (IWMI2000). Their use in Africa is growing and a recentappraisal of their potential has just been published(Kay and Brabben 2000). Some 10 000 pumps arereported to have been sold across West, East andsouthern Africa since 1997 at a cost of US$50–120.Most are used for vegetable production and enablesmallholders to enter the market economy.

The experience of introducing treadle pumps intoAfrica serves as a useful model for the introductionof other irrigation technologies.

Treadle pumps work on the principle of suctionlift using a cylinder and piston to draw water from aresource below ground level, e.g. a river or shallowgroundwater. It was originally developed for thehand pumping of domestic water and has beenskilfully adapted for use in irrigation, where a muchgreater volume of water is needed, by changing thedriving power from arms and hands to feet and legs.These are more powerful muscles and are capableof lifting much more water. Two pistons are used,each connected to a treadle on which the operatorstands and presses them up and down in a rhythmicmotion.

The pumps were initially imported. Now mosttreadle pumps are manufactured locally althoughthey do need special tooling to produce good quality

pumps. The emphasis is on selling pumps to farmerson a commercial basis rather than supplying themas gifts. For this reason the supply chain is a vitalaspect of the pump’s success. These have been setup in Kenya, Zambia and in countries in WestAfrica. The supply chain must also function as aconduit for spare parts, maintenance services andfeedback to manufacturers. The poor uptake ofpumps in Zimbabwe is undoubtedly linked to thelack of an effective supply chain. Although treadlepumps are well known in the country, no agencyhas taken on the responsibility of wide-scalemarketing, and production is not continuous.

The economic benefits of introducing treadlepumps have been significant. In Zambia incomeshave risen more than six fold from US$125,achieved with bucket irrigation on 0.25 ha of land,to US$850–1 700 using treadle pumps. This wasattributed not only to increased crop yields but alsoto being able to increase the area of land irrigated.Cropping intensity rose in some cases up to 300percent (three crops a year) with noticeable increasesin the variety of crops grown. Because of theincrease in water availability, farmers were morewilling to take risks with new crops. Similar benefitshave been reported in other countries where treadlepumps have been introduced.

Problems have also been created through theincrease in crop production. Higher yields can bringabout the problem of a market glut when supplyexceeds demand. This is a particular problem withcommon household crops and it is exacerbated bythe tendency of farmers to grow the same crops atthe same time of year. Exploiting more distantmarkets increases transport costs and highlights theproblem of poorly developed feeder roads in remoterural areas.

Attempts to use treadle pumps in Africa in theearly 1990s were less successful than inBangladesh, because conditions in Africa are verydifferent. The groundwater is much deeper and theirrigated land much more hilly. Water must bepushed further from its source to the point of use.The development of pressure pumps has helped toovercome this constraint in many countries thusresulting in significant sales of pumps over the pastfew years.

Combining treadles with low-cost deliverysystems

Attempts are underway to combine the use of treadlepumps with low-cost water distribution systems such


as trickle kits and hosepipes in Zimbabwe, Kenyaand in countries in West Africa where treadle pumpsare used. The argument is that once water has beenlifted by treadling there is every incentive to use itas effectively as possible. Water is usually pumpedinto tanks for distribution, although there is no reasonwhy it cannot be pumped directly into thedistribution system. The output from a treadle pumptends to be intermittent yet this should not pose toomuch of a disadvantage. However, it is still early tosay if such combinations will be useful.

PREREQUISITES FOR UPTAKE

Enterprise Works, an NGO working in Niger,looked into the prerequisites for uptake of treadlepumps. Many of their findings would apply equallyto other low-cost technologies. In order for atechnology to be commercialized and adopted itshould be produced as close to the end user aspossible. It must be affordable for the buyer andprofitable to the producer. The technology must alsofunction reliably and the purchaser must be satisfied.It only takes a few dissatisfied customers to ruin themarket for a new product. No technology can beconsidered appropriate for all conditions. This iswhere the identification of appropriate sites becomesimportant. Appropriate site criteria include:• a market for vegetable products, usually of higher

value;• a reliable and adequate water source;• a concentration of market gardeners amenable

to innovation;• adequate land available for garden expansion.

The setting up of supply chains and ensuring thatthere is sufficient manufacturing capacity of a highenough quality to meet the demand is also essential.As demand is something that usually needs to bestimulated when new technologies are introduced,there is the opportunity to balance marketingactivities with the development of the supply chains.In this way it may be possible to balance the levelof expectation created among farmers with themeans of satisfying it.

To be profitable a technology must have a lowoverall cost that does not expose the owner to debt.It must then make money. Fear of failure has oftendriven people towards high tech solutions to avoidthe problems of breakdown. All machinery failseventually and in developing countries, failure tendsto occur sooner because maintenance is poor andconditions more hostile. The result is machinerygraveyards that can be seen surrounding many townsand villages. For this reason the need for strongsupply chains to support the supply of spare partsand maintenance must not be underestimated.

A ROLE FOR LOW-COST TECHNOLOGIES IN SUB-SAHARAN AFRICA?

Comments about the role of low-cost irrigationsystems in sub-Saharan Africa are similar to thosemade for modern technologies. Low-cost systemshave the potential to raise productivity and enhancerural livelihoods. Even though costs for thesetechnologies may be relatively low they are still onlyaccessible to farmers who can afford to buy them.Usually they are growing cash crops such asvegetables, fruit and flowers that provide sufficientreturns to pay for the investment. They have little tooffer poor farmers and so are unlikely to be takenup by them without appropriate financial andtechnical support.

Low-cost systems have yet to be tested andevaluated properly in the region. There are alsoconcerns about commercial interests encouragingfarmers to use modern technologies when other lessexpensive options may be appropriate.

One exception to this is treadle pumps, whichhave been undergoing various evaluations in thelaboratory and in the field over the past five years.So far the results in terms of uptake and benefitshave been encouraging. Their adoption bysmallholders and the way in which support serviceshave been developed is undoubtedly a model thatthe developers of other technologies might emulate.


Matching technologies to agricultural regions

The most appropriate technologies to use will varyfrom place to place depending on a wide range ofcircumstances. A broad classification may be madebased on climate, Figure 2, and the traditionalagricultural background of local people. Table 3links technology options to agricultural regions andTable 4 links them to countries.

Irrigation has been associated with the floodplains of large perennial rivers. Major examplesinclude the Niger River in Niger, Mali and northernNigeria, the Senegal River in Mauritania andSenegal and the Juba and Shebelli Rivers inSomalia. Outside the region the Nile in Sudan andEgypt is famously associated with irrigation. Theseareas have always been prime sites for large-scaleirrigation schemes and have long traditions ofsmallholder irrigation. For instance, in Niger, duringthe wet season, floating rice is planted in the riverbed at the beginning of the rains and is flooded asthe river rises. Later, from November to April, smallvegetable gardens are cultivated on the river banksand alluvial terraces that are not flooded during peakflow in January-February. When the floods recedecrops such as sweet potatoes, maize and onions areplanted and irrigated from shallow groundwater.Small pumps are gaining increasing acceptance inmany countries wherever spare parts and fuel arereadily available.

DESERT AND SEMI-DESERT

This zone is characterized by very low, erraticrainfall (less than 500 mm per annum), whichrenders purely rainfed agriculture impossible. Themajor agricultural activity is nomadic stock raisingwith camels, goats, sheep and cattle being theprincipal stock. In this zone the most important formof smallholder irrigation development is likely tobe water harvesting. Spate irrigation could also bepractised in occasional watercourses as well asshallow groundwater development.

In some places such practices are traditional. Forexample, in the Lower Omo Valley in Ethiopia,(rainfall 300 mm/year), fodder and food cropproduction depends almost entirely on seasonalfloodwater from the River Omo and recessionfarming in the old river channels. Successful systems

of run-off farming have also evolved in the adjacentWoito Valley.

The techniques of runoff agriculture are still atan experimental stage in Africa (see Tanzania box).The success of smallholder schemes in these regionsis to a large extent dependent on the acceptabilityof settlement to the nomadic tribes who generallypopulate this area. Without their cooperation anyirrigation development is likely to be unsuccessful.

Water harvesting is the only alternative to makinga living through semi-nomadic stock raising orfamine relief. Where these semi-nomadic peoplehave become destitute, as is happening in vast areasof Ethiopia and Somalia, they may be prepared tosettle on permanent smallholder irrigation schemes.The future prospects for this zone are not promisingbecause of the increasingly tight definitions ofboundaries and territories and continuingencroachment of agriculture into traditional pastures.

An example of the establishment of waterharvesting by semi-nomadic tribes was in Turkanain northern Kenya in the early 1980s. There werereports of local resistance in the form of apatheticattitudes and inherent scepticism towards the ideathat crops could be produced on what wastraditionally regarded as grazing land. Once therewas demonstrable success in increasing fodderproduction the level of participation grew rapidlyand a large number of fields were under regularcultivation producing grain, fodder and wood.

DRY SAVANNAH AGRICULTURE

This zone extends over large areas of Africa. Itdiffers from the desert and semi-desert zone inhaving a higher annual rainfall of 500–600 mm(occasionally up to 1 000 mm) which falls in a singlethree to six month long rainy season. The main formof agriculture is sedentary stock raising in someareas and arable farming in others. The types ofirrigation likely to succeed in these areas are waterharvesting and irrigation of river flood plains andother extensive plains, either in the wet season withbunds to control occasional floodwaters or withexploitation of shallow groundwater throughout theyear.

Matching technologies to agricultural regions28

Figure 2. Agricultural regions of Africa in relation to smallholder irrigation

Table 3. Relative importance of small-scale irrigation in agricultural regionsRegion River flood plains

Wetseason

Dryseason

GroundwaterSwamp

irrigationHill

irrigationRainwaterharvesting

Desert and semi-desert 2 1Dry savannah agriculture 2 2 1Humid savannah agriculture 2 1 3 3Humid tropical forest agriculture 3 1 3 1Pastoral stock raising 1Semi-nomadic stock raising 1High tropical and sub-tropical Plateau agriculture 1Irrigated agriculture 2 1 3

Note: 1 very important, 2 fairly important, 3 less importantSource Kay et al. 1985


An example of successful runoff agriculturecomes from Burkina Faso where an NGO initiateda combined agro-forestry and water-harvestingproject. In 1979 a small experimental area of microcatchments for fuelwood trees was established withfarmer participation. The farmers involvedsubsequently adopted these runoff-farmingtechniques and used them to improve theirtraditional erosion control methods, thus increasingtheir normal agricultural production. Fields longabandoned are being reclaimed and farmers areincreasing infiltration through the construction ofsimple contour bunds.

HUMID SAVANNAH AGRICULTURE

In this zone the annual rainfall is normally, 1 000–2 000 mm, falling either in two rainy seasons closeto the equator, or as one long rainy season furthernorth or south. This is sufficient to grow two rainfedcrops in countries close to the equator (e.g. Rwanda,Burundi, Central African Republic) and onerainfed crop in a more northerly or southerly area.The role of irrigation in this zone is therefore to (a)improve the yields of existing crops, such as maize,groundnuts and cotton, (b) to reduce risks byextending the length of the growing season orallowing a second (or third) crop to be produced inthe dry season, and (c) to allow new areas of landto be developed for crop production throughdrainage of swampy areas for dry season croppingor water control for wet season rice growing.

In general, in countries with adequateagricultural land reserves, the main emphasis shouldbe on the development of improved agronomictechniques in rainfed agriculture. However, wherethe available agricultural land is scarce and thepopulation is high there will be an inevitableacceleration in the development of irrigation.Rwanda is a prime example of this with an averagepopulation density over 200 persons/km2.

The physical types of irrigation will largelydepend on the topography of the areas but mostirrigation will be on river flood plains or extensiveplains. Emphasis will be on supplementary irrigationin the dry season, followed by control of water inthe wet season for rice cultures. Irrigation of smallareas from channels and non-seasonal irrigation inflood plains and extensive plains will be importantin localized areas.

HUMID TROPICAL FOREST AGRICULTURE

This zone is the wettest region with annual rainfallin excess of 1 500 mm, usually falling in two mainwet seasons. This zone therefore differs from othersin that it is wet throughout most of the year and hasno major constraints to rainfed agriculture, exceptduring the short intervening dry season. The majorirrigation issues will be concerned with water controland drainage rather than with irrigation per se,although supplementary irrigation can be practisedparticularly for crops, such as vegetables grown inthe short dry season as in parts of Nigeria. The mostimportant will be small areas commanded fromweirs and channels, such as the inland valleyswamps of Sierra Leone, Liberia and Guinea. Inthe wet season, deep-water rice may be grown inthe same small swamps. In Togo and Benin the mainform of irrigation will involve small to medium-sized earth dams commanding the downstream areasby channels and with various lifting techniques, forirrigating upstream of the dams. In coastal regionsthere are large areas of rice grown in the mangroveswamps and in river estuaries during the wet season.Sierra Leone has 20 000 ha of mangrove swampscropped with a potential for 74 000 ha.

HIGH TROPICAL AND SUBTROPICAL PLATEAU

AGRICULTURE

The high tropical and subtropical plateaus, whichare greater than about 1 500 m above sea level arecharacterized by low temperatures, particularly inthe cool seasons away from the equator, which canrestrict the choice of crops. Rainfall varies from 500mm/year upwards.

The most suitable form of irrigation will varydepending on topography and rainfall but willgenerally involve small areas commanded bychannels. In the high veld of Zimbabwe many smallfarm dams have been constructed in smallcatchments that are used for smallholder irrigationand stock watering. The techniques employed inZimbabwe tend to use modern technology withsprinkler irrigation being very important. In theRumphi district of Malawi small channels lead awayfrom streams to suitable areas for irrigation, whichmay be several kilometres away. In many of theareas (e.g. South Tanzania, Zambia, Malawi),supplementary irrigation of cash crops such as teaand coffee during the extended dry season ispractised commercially and opportunities exist toextend this to smallholder schemes.


How fast can smallholder irrigation develop?

It is important that agencies wishing to supportirrigation development have some idea of how fastfuture irrigation development can take place so thatthe agencies can plan for the labour and technicalresources they will need to provide. Given thecurrent socio-economic constraints on smallholdersthe question is a difficult one to answer. Removingconstraints can encourage farmers to move intoirrigation and speed up the process but this is noteasy and so major changes are unlikely in theforeseeable future.

One option is to look at what has happened inthe past decade as an indicator of what might happenin the future.

REVIEW OF EXPERIENCE FROM SUB-SAHARAN AFRICA

A recent review of IFAD’s smallholder projects(Internal review 2000) is of particular interest notonly because of its wide geographical spread butbecause it highlights the challenges that face anyinternational agency wishing to support smallholderirrigation in what is essentially the private sector.As the majority of such investments tend to go tothe larger schemes involving communities, ratherthan to support individuals, they have inherentlyhigher risks built into them. Past experience hasshown that individual farmers developing irrigationon their own or with family have a much lower riskof failure than those who work in groups orcommunities requiring collective responsibility anda sharing of the assets.

In 1986 IFAD launched its special programmefor countries affected by drought and desertificationin sub-Saharan African in response to the devastatingdroughts of the 1980s with a sub-programme, Small-scale Irrigation and Water Control. The principalobjectives were to increase smallholder productivecapacity, improve household food security and buildthe capacity of farmers to take over schemeoperation and maintenance responsibilities byinvolving local communities. This was to beachieved through the development of a widespectrum of simple low-cost technologies. Theadoption of a participatory demand-driven approachwas considered essential for ensuring sustainability.

Under this approach, it was assumed thatbeneficiaries would be key partners involved in theselection of activities, their design and subsequentimplementation.

In all, more than 80 000 were to benefit,including an appreciable number of women headsof households, and an area of 20 000 ha would beirrigated. The schemes included:• Individually owned systems (7 percent of

schemes). Small mobile pump schemes orvarious lift systems using seasonal river flow,stored water in ponds, or shallow aquifers.

• Community-based schemes with partialcontrol of water (21 percent). Water harvesting,inland bottom valley schemes, and floodrecession and control in West Africa.

• Communal gravity or pumping schemes(46 percent). Pumping systems operated by thevillagers, mostly developed in West Africa;gravity smallholder irrigation schemes based onthe diversion of water stored in small dams(Ghana); and collective tube-wells withsubmersible pumping systems using deepgroundwater (Senegal, Niger).

A review of the projects has produced somevaluable insights into the challenges that this kindof intervention faces. Many of the projects were stillbeing implemented and so a full assessment of theirimpact was premature. It was possible to see theprogress made and identify the constraints that hadhampered their implementation. Some of the keyfindings of the review included:

Impact on smallholder living conditions

In most cases the projects had a favourable impactin that they generally expanded the irrigated area,increased water availability and improved its use.

In regions where water supplies are dependablethey enabled producers to use water forsupplementary irrigation in the rainy season, tomitigate the effects of erratic rainfall on theirtraditional crops and, in the dry season, to producehigh-value cash crops, (Ghana, Ethiopia, Sudanand Niger). In Niger about 400 smallholders, who

How fast can smallholder irrigation develop?32

had difficulty in making the initial investment fromtheir own resources, benefited significantly.Smallholders were able to buy small mobile pumpsand in this way avoid being dependent on privatewealthy pump owners, to whom they formerly hadto pay one third of their harvests in exchange forrental of similar equipment. In Senegal, farmerswere able to increase their irrigated plots and thequality of construction was improved makingmaintenance easier. In Ghana, farmers benefitedfrom irrigation during the dry season and saw thisas the single most important factor in theachievement of household food security.

Impact on women’s access to natural resources

Almost all projects had as a goal the introduction ofincreased equity and security in access to developedland, especially by women. In Tanzania andGhana, about a third of the irrigated plots wereallocated to women. In addition, women reportedlycontributed much of their labour towards schemeconstruction in order to assure themselves of a plotor extra income. However, it was mainly men whodecided on land tenure issues rather than women(The Gambia, Mali, Senegal and Ghana). This stillcontinues to be the case and the projects have notchanged this.

Farmers’ participation

Conventional wisdom calls for farmers to becomethe principal partners and decision-makers in aproject because this is perceived as the best way ofensuring ownership and development success. Forthis reason participatory approaches were a centralplank of the planning phase. In practice, however,the projects were implemented under a project-ledrather than a demand-driven approach. Participationwas sacrificed in favour of speeding constructionactivities in order to develop as many schemes aspossible. Even in cases where participatoryprocesses were used, schemes were usually designedin response to requests received by ProjectManagers. These were often based on the perceptionof landowners and village chiefs had of priorities,rather than those of the direct beneficiaries.

Generally, people implementing the projects didnot have enough experience of participativetechniques or were not convinced of theirimportance and paid only lip service to the process.Farmers were not always willing to contribute their

labour for free, preferring instead to work on theirfarms or for off-farm income-generating activities.This was contrary to the early expectations thatpeople would be willing to invest their labour andthis would engender a feeling of ownership. In manycases labour had to be paid for, which madetranslating theory into practice difficult. Time wasalso a major constraint. The demands of farmerparticipation, which require time to evolve, did notfit with the short time constraints that agenciesnormally place on project investment andconstruction possesses. The result was that the paceof development was much slower than originallyanticipated.

Many projects failed to get farmers to participate.They were not convinced of the need to take fullresponsibility for bringing land into production,which in most cases they did not own. They wouldnot take on the responsibility for operation andmaintenance, which was viewed by farmers as agovernment provided source of employment andincome rather than a self-help activity. Increasinglyfarmers are becoming aware that substantial supportand subsidies can no longer be expected from thegovernment and that they must begin to rely on theirown efforts.

Suitable technologies

When dealing with communities living in harshenvironments, existing production systems givefarmers some basic security from starvation, evenif they have low yields. Any external interventionshould be developed around existing systems ratherthan bringing in new technologies. Expectations ofcropping intensity, yield and reduced water wastage

THE CHALLENGES OF PARTICIPATION

An engineer-agronomist told the anthropologistthat he worked in close collaboration with thefarmers every time he went out in the field. Bythis he actually meant that he was accompaniedby the manager of the perimeter and the head ofthe county government.

In another instance, at an introductory meetingof experts, who were going to work together onan irrigation project, the anthroplogist wasintroduced for the first time to the irrigationengineer who said, as they shook hands, ‘Whatare you doing here, we don’t need you. We knoweverything we need to know about the farmers’.

From Brown and Nooter (1992)


need to be realistic. The outcome is determined moreby the capacity of small-scale farmers to adopt newtechnologies where services are erratic and marketprices are high, rather than on what is potentiallypossible.

Although irrigation is meant to reduce risk, newtechnology introduces other risks that might exposefarmers to a higher level of risk than before. Projectreviews have shown that this extra risk fallsexclusively on the farmers without being shared bythe government. This has resulted in conflictsbetween farmers and credit institutions, and infarmers abandoning projects.

The most successful technologies proved to bethose initiated to improve existing farming systemsand which continue to be under the full control ofthe communities or individuals, such as floodrecession improvement, individual low-lift pumpingsystems, and abstraction and diversion of water fromrivers. The risks increased considerably whenlarger-scale pumping from tubewells for wholecommunities was introduced.

The idea of using ‘low-cost technology’ isattractive to donors and farmers alike although itcan and does create problems. There is usually anassumption that once a scheme has been planned,the design and construction is a straightforwardprocess and the outcome is a well-engineeredsystem of supply that farmers can use withconfidence. This is not always the case and thephrase ‘low-cost technology’ is in danger ofbecoming a euphemism for poor engineering designand construction. Canal embankments are often notcompacted properly and so they do not last verylong. Concrete is not prepared properly andcompacted during placement with the result that itcrumbles during use and so structures do not giveadequate service. If the technology does not workproperly, the seeds of failure are already sown.

The principal reason for much of the poorengineering was a serious shortage of suitablytrained irrigation engineers and technicians whocould undertake design work and supervizeconstruction properly so as to produce soundengineering works.

Prospects for development

Many countries south of the Sahara are becomingincreasingly dynamic in response to more liberalmarketing and pricing policies and greatercompetition between private sector interests. Thereare concerns that while the state may withdraw from

a number of functions that may be better handledby the private sector, assistance for smallholderirrigation schemes targeting the poorest of the ruralpopulation can be expected to remain an importantarea for public sector investment and support.Without targeted assistance, at least during atransition period, the rural poor will becomeincreasingly vulnerable to the new emphasis on an‘open economy’ environment, and hopelesslymarginalized.

Simple and appropriate water controltechnologies are becoming better known, and somedecline in unit costs of development can be expectedas smallholder irrigation systems gain greatercredibility and farmers’ awareness of their role andresponsibilities in relation to water managementincreases. The institutional capacity of governments,NGOs and the private sector to work together is alsoimproving. These factors would support continuedinvestments in smallholder irrigation, especiallysince without investment in water infrastructure theprospects for increasing food production andimproving food security are remote in manycountries. Table 5 summarizes the technical andinstitutional issues and gives an indication of costs.

Summary of IFAD review

The following summarizes some of the key lessonslearned from the IFAD review:• The identification of local community

representatives or farmers’ organizations capableof acting as responsible partners is a prerequisitefor any smallholder irrigation development.Beneficiary involvement should be a partnershipprocess where each partner has the right to agreeor not and therefore has the capacity to influencethe decision and to share in the responsibility. Inaddition, attention should be given to matchingthe scale and scope of a project with theimplementation capacity of local institutions andthe farmers’ capacity to participate.

• A detailed plan and procedures should beestablished so that implementers are wellprepared for the tasks expected of them. Thiswould not be a simple detailed list of physicalactivities, but rather a plan of who should dowhat, when and how.

• A distinction should be made between projectsaiming to improve existing practices under theresponsibility of traditional communities/villagesfrom those introducing new ideas andtechnologies.


• More attention should be paid to the criteria forsite selection, targeting and implementingprocedures. Several rounds of project design andconsultation are needed if the trust and assistancefrom groups of farmers is to be forthcoming.Time is needed to apply a participatory approachand to create necessary capacities at the locallevel.

• The free labour that beneficiaries are expectedto contribute should be no more than theequivalent of 15 percent of the total costs. It isessential that this contribution is recognized asbeing at the expense of other demands on theirtime.

• Appropriate methods of construction appear tobe those that optimize the use of small localcontractors and the labour of the beneficiaries,combined with independent professional checkson the design and construction standards toensure these conform to specifications.

• It is essential to prepare an agreement betweenthe sponsoring agency and the beneficiariesspecifying their respective roles, contributionsand obligations during construction and later foroperation and maintenance. Cost recovery and

financing mechanisms and procedures are still amajor problem in many countries and still needto be worked out. Agreement must be reachedon appropriate mechanisms based on thetechnologies used, the cropping system and theorganizational features of farmers.

• Forming Water Users’ Associations (WUAs) andtransferring project assets to them proved to bea long and difficult process incompatible withthe short period of project implementation. Thishas administrative, financial and legalimplications. Therefore, adequate support isneeded for the creation of WUAs and for trainingmembers and office holders sufficiently early inthe course of a project to ensure they are properlyprepared to assume operation and maintenanceresponsibilities.

• It should be taken into account that effectivebeneficiary involvement and development of asense of ownership is not always achievable forevery type of scheme.

• Other support services (agricultural extension,input supplies, market access, rural finance, landallocation, etc.) must also be in place. A realisticassessment of the institutional viability of

Table 5. Summary of IFAD funded smallholder developmentsTraditional Community based

schemesIndividuals and private

schemesInter-village and

communities schemesType and nature ofsystems

Water harvesting. Inland valleybottom. Flood recession

Small mobile petrol pumps.Various lift systems (treadlepumps, wind pumps, etc. Smallcollective pumps

Village irrigated. Diversionfrom rivers and small dams.Deep tubewells

Water usersassociation

Not necessary/communitymatters

Not necessary, individuals orsmall groups responsibility

Necessary

Water management Necessary because of impact onother communities

External monitoring necessaryto avoid depletion of aquifers

Necessary for sustainability

Risks Limited risk Medium risk. No sharing of risk High risk. Sharing mechanismneeded

Average cost (US$/ha) 600 to 1 000 1 500 to 3 000 3 000 to 8 000

Figure 4. Rates of irrigation development in selected countries

0

5 0

1 0 0

1 5 0

2 0 0

1960

1965

1970

1975

1980

1985

1990

1995

1997

E th io p iaM a liZ im b a b w eZ a m b iaS . L e o n eB u rk in a F a s o


securing these services during implementationis essential.

EXISTING SITUATION

No recent and accurate information is available onthe full extent of smallholder irrigation in sub-Saharan Africa. In this section an attempt is made,based on available data, to look at what has alreadybeen achieved and at future possibilities on acountry-by-country basis. The speed of pastdevelopment may hold clues as to how fast we canrealistically expect developments to be made in thefuture.

The extent of irrigation development and how ithas changed over the period 1960 to 1997 issummarized by Gleick (2000) on a country-by-country basis using FAO data sources. What is notreadily available, however, is the current extent ofsmallholder irrigation relative to larger-scaledevelopments. For this it is necessary to go back to1986 when FAO estimated the split between the two.For this reason the FAO 1986 data are used to showthe extent of smallholder irrigation in relation to thetotal developed in 1986. A comparison is made ofthe estimated potential for irrigation based onavailable land and water resources (Table 6). Inaddition to this, data from 1985 to 1997 (a 12 yearperiod) quoted by Gleick have been used to calculatethe average rate of irrigation development(smallholder plus large scale) in each country (seelast column in Table 3). As this information providesan important insight into the capacity of each countryto expand irrigation development in the future, thecountries have all been ranked according to this rateof development.

The FAO consultation in 1986 concluded that in32 of the 40 countries in sub-Saharan Africa, thefirst priority was for rainfed agriculturaldevelopment. In eight countries Botswana, BurkinaFaso, Kenya, Niger, Mali, Mauritania, Senegaland Somalia, irrigation is an essential part of anyfood security strategy because of the populationpressures and the lack of rainfed capacity.

FAO data also show that sub-Saharan Africaincludes 11 of the 16 nations of the world havingless than 1 000 m3/head/year of water, a situationdescribed as ‘absolute water scarcity’ where foodshortages are a constant threat and water shortagecan only increase (FAO 1995).

What is clear from the data is that the potentialfor further irrigation development in terms of landarea and, to a lesser extent, water availability is very

significant even allowing for the development thathas taken place over the past 14 years (since 1986).Although there may be some differences over thedefinition of smallholder irrigation, the table clearlyshows some 66 percent of irrigation developmentis in this sector. Since the emphasis in the intervening14 years has also been on smallholder irrigation thetrue percentage may be even higher.

The average rates of development of irrigationover the past 12 years (1985-97) provide aninteresting insight into what has been achieved ineach country and what might be achieved in thefuture. Of the eight countries identified by FAO asbeing dependent on irrigation, the rate ofdevelopment in Botswana, Mauritania andSenegal has been zero, whereas Burkina Faso,Kenya, Niger, Mali and Somalia are in the top 14best performing countries.

Unfortunately, even in the countries most activein irrigation the rates of development are still verymodest and over 50 percent have a rate less than500 ha/year. In fact 13 countries show no growth atall. It may well be that irrigation is not as importantin those countries. There are some on the listhowever that would clearly benefit from someresurgence of interest in irrigation. The totalestimated rate for the whole region is 43 600 ha/year – an average of 1 150 ha/year for each country.

Some countries appear to have encouraging ratesof development (e.g. Tanzania, Nigeria, Niger,Zimbabwe and South Africa – the latter two arespecial as they have substantial private irrigationsectors). The question is, can this rate be sustainedor increased in the future? Many developmentprocesses follow a classic ‘S’ curve and irrigationis no exception. The curve usually has three distinctphases:

• A preliminary lag phase at the start of a newinitiative when the ideas and technologies arerelatively unknown and untried.

• An intermediate, rapid growth phase which takesplace when the area under irrigation is beingexpanded very fast with active farmerparticipation using by now well tried and testedtechniques.

• A tailing off into a flatter section when theavailable land or water is nearly used up and anyfurther developments are on marginal areas withless potential benefit to the farmer.Data from five countries over the period 1960 to

1997 demonstrate this, see Figure 4. Two countriesare in the lower development rate group and three


are in the higher group. In each case it is apparentthat development has past through the rapid growthphase and is in the tailing off phase. These data aretypical of all the countries listed in Table 6, whichall exhibit a similar trend.

The realities of these development curves add tothe view that it is factors other than natural resourcesthat constrain development. These includemarketing, infrastructure, availability of fuel andspare parts, social background, labour availability,pricing policy, population density and land

availability as well as the knowledge and expertisein irrigation technology.

FUTURE POTENTIAL

If the above data foretell the future then rates ofdevelopment are likely to be slower than over thepast 12 years unless the key constraints are identifiedin each country and steps taken to remove them.

Table 6. Irrigated areas in sub-Saharan Africa in 1982Country Potential

(000ha)

Large-scale

(000ha)

Smallholder

(000ha)

Total

(000ha)

% developed Rate ofdevelopment

(ha/yr)Angola 6 700 0 10 10 < 1 0Botswana 100 0 12 12 12 0Burundi 52 2 50 52 100 0Cameroon 240 11 9 20 8 0Congo 340 3 5 8 2 0Guinea Bissau 70 na na na na 0Lesotho 8 0 1 1 13 0Liberia na 3 16 19 na 0Mauritania 39 3 20 23 59 0Rwanda 44 0 15 15 34 0Senegal 180 30 70 100 56 0Togo 86 3 10 13 15 0Uganda 410 9 3 12 3 0Gambia 72 6 20 26 36 83Mauritius na 9 5 14 na 83Sierra Leone 100 5 50 55 55 83Congo DemocraticRepublic

4 000 4 20 24 1 167

Gabon 440 0 1 1 < 1 250Namibia na na na 4 na 250Ghana 120 5 5 10 8 333Guinea 150 15 30 45 30 417Swaziland 7 55 5 60 >100 583Chad 1 200 10 40 50 4 833Malawi 290 16 4 20 7 833Burkina Faso 350 9 20 29 8 1 083Benin 86 7 15 22 26 1 167Mozambique 2 400 66 4 70 3 1 167Zambia 3 500 10 6 16 <1 1 500Cote d’Ivoire 130 42 10 52 40 1 583Kenya 350 21 28 49 14 2 083Mali 340 100 60 160 47 2 167Somalia 87 40 40 80 92 1 667Ethiopia 670 82 5 87 13 2 333Tanzania 2 300 25 115 140 6 2 333Nigeria 2 000 50 800 850 43 2 750Niger 100 10 20 30 30 3 000Zimbabwe 280 127 3 130 46 5 000South Africa 11 833Central AfricanRepublic

1 900 0 4 4 <I na

Equatorial Guinea na na na na na naTotal 29 141 778 1 531 2 313 16.6 43 583

Source: FAO 1986 and Gleick 20001

1Countries are ranked in terms of their rate of irrigation development over the past 12 years


If the current rate is sustained then an extraone million ha of irrigation could be brought intoproduction in the next 25 years – only a 50 percentincrease on what has already been achieved. Tosustain this rate, let alone increase it, would requirenot only massive investment but also a considerableleadtime of several years to build the infrastructureand the absorptive capacity to support it. In view ofthis, perhaps a more realistic estimate might be halfthis – say 0.5 million ha.

Many leading experts recommend thatdevelopment should be a slow, incremental processrequiring low investment sustained over a long

RATES OF DEVELOPMENT

In general, areas with small reserves of land and high populations are likely to show the fastest change asfarmers will be under pressure to intensify their agricultural production in the face of falling land availability. InBurundi the first record of the use of valley swampland appeared in 1936. By 1959 this had risen to 200 haunder dry season cultivation and by 1975 had increased to 4 000 ha. By 1979 a survey recorded 5 700 ha ofswamp irrigation, an increase of nearly 43 percent in four years (Gerard 1982 in Hekstra 1983).

A similar growth curve was observed in Nigeria with an increase in traditional fadama irrigation from 120 000ha in 1958 to 800 000 ha in 1978. This has gone on with little or no support from the Government. This growthin smallholder irrigation contrasts strongly with the actual development of formal large-scale irrigation inNigeria. The lag phase has lasted more than 30 years. This is contrary to the predictions of both the FederalDepartment of Agriculture and the World Bank, that predicted areas of 320 000 ha and 125 000 ha respectivelywould be under irrigation by 1982. By contrast the actual total area under formal irrigation in 1982 was only30 000 ha. The declared total irrigation in Nigeria in 1995 was 2.3 million ha and the majority of this is likely tobe in the smallholder sector.

Carter et al. (1983)

period. Some argue that low world grain prices arethe main cause of irrigation stagnation, put simply,irrigation does not pay well at the moment. Increasesin grain prices would stimulate the markets andencourage farmers to produce more. The messageis clear; it is not the availability of physical resourcesthat is likely to constrain the development ofirrigation in Africa but economic, social andinstitutional constraints that could hamper progress.Unless radical steps are taken to ease theseconstraints the result will be only a modest reductionof Africa’s food problems over the next 25 years.


The right direction: prospects forsub-Saharan Africa

For smallholder irrigation development to succeedin sub-Saharan Africa experience shows that severalbroad issues must be addressed.

• Technology plays a central role in irrigationdevelopment. It can reduce the drudgery of liftingand distributing water and in the process makemore effective use of limited water resources.Selecting the most appropriate technology is anessential pre-requisite for success.

• Smallholder irrigation should be a slowincremental process of improvement with lowinvestment over a sustained period (perhapsgreater than five years).

• Assistance given to farmers should be of a self-sustaining nature, which does not requirecontinuous support from an external agency overan extended period.

• Any system set up to respond to farmer demandis more likely to succeed than one which isimposed, however well meaning this might be.

• National and local NGOs are more likely toreflect local needs for irrigation than governmentand so there is a need to link more strongly theactivities of NGOs with the developmentprogrammes of government and aid donors forthe benefit of all.

• In the current climate of public sectorretrenchment it will be important to ensureprivate sector involvement in the manufacture,promotion, supply and support of irrigationtechnologies.

• Access to credit, particularly informal systems,will continue to be important to ensure thatirrigation equipment and inputs are sufficientlyaffordable and accessible to farmers.

Of particular importance is the need to strengthenand sustain the education and training ofprofessionals, technicians and ultimately farmingcommunities. Only by developing the skills andbroadening the experience of the farmers and theinstitutions created to support them, can the benefitsoffered by technological innovation be takenadvantage of.

DEVELOPING HUMAN RESOURCES

Training in irrigated agriculture is a wide andcomplex issue. It is raised here in the context ofirrigation technology, i.e. as it concerns the planning,design, construction and maintenance of irrigationschemes. FAO (1985) identified the problems ofhuman resources development in irrigation and thedearth of experienced people across the irrigationsector that can put plans into action. Moris (1984)also refers to the lack of suitable training at thesmallholder level, particularly in water control andmanagement and emphasizes the need for trainingboth farmers and government personnel. A reviewof IFAD’s experience over the past 20 years or sohighlights a serious shortage of suitably trainedirrigation engineers and technicians. It cites this lackof people who could undertake design work,supervize the construction properly and to producesound engineering works, as the principal reasonfor much of the poor engineering on schemes. Itwould appear that the situation has not generallyimproved over the past 15 years.

It is difficult to attract people into irrigation fora variety of reasons and it can take many years forindividuals to build up sufficient experience for thiswork. There are not enough people having thetechnical skills and experience to design and buildschemes properly and who have sufficientexperience in participatory methods. There are alsotoo many examples of inappropriate training oftechnicians. Many are still learning aboutsophisticated technologies practised in the UnitedStates because this is what their teachers learned.Too many instructors are more concerned aboutshowing what they know rather than getting goodideas across. Too much training is done in theclassroom and not enough in the field. Too manytechnicians lack the skills to work closely withfarmers and assume that communication is abouttelling farmers what to do rather than listening.

For smallholder irrigation to develop it will beessential for each country to undertake a study oflabour requirements to assess the supply and demandfor trained people. Demand is based on the expected

The right direction: prospects for sub-Saharan Africa40

A LACK OF SKILLS

This is not an overstatement of affairs. An engineer-agronomist told the anthropologist that he worked in closecollaboration with the farmers every time he went out in the field. By this he meant that he was accompanied bythe manager of the perimeter and the head of the county government. In another instance, at the introductorymeeting of experts who were going to work together on an irrigation project, the anthropologist was introducedfor the first time to the irrigation engineer who said, as they shook hands, ‘What are you doing here, we don’tneed you. We know everything we need to know about the farmers’.

Anthropologists or sociologists hired for project teams are often either geographic specialists who know thearea but not irrigation and are unaware of the precise information technicians need to make decisions, or theyknow irrigation but not the geographical area and so they do not understand the local farmers’ interests andsocial, economic and agronomic constraints. Both options give disappointing results. Technicians andgeographically specialized sociologists need to work more closely together so that the sociologists understandclearly the kinds of information that will be useful to the technicians.

From Brown and Nooter (1992

growth rates in irrigation and the supply of trainedpeople, at all levels, is based on the output fromboth the institutional and in-service trainingarrangements. Curriculum support is needed toestablish appropriate institutional and in-servicetraining programmes that properly equip people for

the jobs they must do. With wider acceptance andapplication of appropriate irrigation technologiessmallholders in sub-Saharan Africa may then be ina position to increase crop production and in thisway improve their rural livelihoods.


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