Cover Image
close this bookDesign and Operation of Smallholder Irrigation in South Asia (WB, 1995, 134 p.)
View the document(introduction...)
View the documentForeword
View the documentAbstract
View the documentChapter 1 - Introduction
close this folderChapter 2 - Profile of the smallholder
View the documentFractionation and consolidation of the smallholding
View the documentSmallholder attitude toward farmer-owned and government systems
View the documentCultivator willingness to undertake more intensive cultivation
View the documentSmallholder attitude toward credit
View the documentTheft and vandalism of control structures
close this folderChapter 3 - Land shaping and water distribution at the field level
View the documentLand shaping by the cultivator vs. institutionally
View the documentLand shaping and water management in smallholder irrigation
View the documentLand shaping as a project component
close this folderChapter 4 - Water supply and demand
View the documentDegree of storage regulation
View the documentIntensity of irrigation
View the documentCrop water requirements and crop water response
View the documentEffective rainfall
View the documentThe particular case of water requirements for paddy
close this folderChapter 5 - Cropping patterns in irrigation design
View the documentThe degree of control of selection of crops
View the documentCropping pattern design and project formulation
close this folderChapter 6 - Irrigability
View the documentSoil surveys and land classification
View the documentSoil constituents
close this folderSoils problems on irrigation
View the document(introduction...)
View the documentSaline and alkaline soils
View the documentExpansive days
View the documentGypsiferous soils
View the documentAcid sulphate soils (cat clays)
View the documentPodzols
View the documentLateritic soils
View the documentDune sands
close this folderChapter 7 - Canal systems for smallholder irrigation
close this folderIntroduction and definitions
View the document(introduction...)
View the documentDesigning for variable supply
View the documentVarying demand within the service area
View the documentAllocation of water and establishing water charges
View the documentCapacity of primary and secondary canals and size of irrigation area
close this folderDistribution at the tertiary level
View the documentBackground
View the documentTertiary system design for non-paddy crops
View the documentTertiary system design for areas primarily under paddy
View the documentTertiary system design for mixed cropping
View the documentLayout of tertiary channels
close this folderChapter 8 - Hydraulics of canal regulation and types of control structures
View the documentBackground
View the documentDownstream control with limited demand
View the documentUpstream control with rotational delivery
close this folderHydraulic controls on secondary and tertiary canals
View the documentDownstream control
View the documentUpstream control
View the documentHydraulic controls on primary canals
View the documentProduction of small hydraulic structures
close this folderChapter 9 - Operation and maintenance
View the documentIntroduction
View the documentInadequate budget for O and M
View the documentDesilting of canals
View the documentWeed control in canals
View the documentOperation of partially completed systems
View the documentNight irrigation
View the documentMonitoring of project performance
View the documentApplication of computers to irrigation system operation
View the documentSocial and political pressures in system operation
close this folderChapter 10 - Durability of canal linings
View the documentReasons for lining
View the documentCauses of deterioration canal linings
View the documentConstruction materials for primary and secondary canal linings
View the documentConstruction materials and production methods of tertiary canal linings
close this folderChapter 11 - Construction and maintenance problems of drainage works
View the documentDrainage and the cultivator
View the documentFormal and informal tertiary drainage systems
View the documentSubsurface field drainage
View the documentPrimary and secondary drainage
close this folderChapter 12 - Cultivator organizations
View the documentCultivator organizations in irrigation system operation
View the documentTraditional organization in village-level irrigation schemes
View the documentProjection from the village-level organization to cultivator organizations in public systems
View the documentExperience and problems with water user groups in public irrigation systems
close this folderChapter 13 - Village schemes and small tank projects
View the documentBackground
View the documentFarmer-constructed diversion systems
View the documentVillage schemes with storage
close this folderChapter 14 - Groundwater development
View the documentIntroduction
View the documentSmall, individually-owned, suction-mode wells
View the documentIndividually owned and group owned force-mode wells
View the documentLarge capacity public tubewells
View the documentTechnical problems in design and construction of medium and large tubewells
View the documentWater distribution from medium tubewells
View the documentFunctions of the tubewell operator
View the documentPower supply problems
View the documentComparison of medium and large wells
close this folderChapter 15 - Conjunctive use of surface and groundwater
View the documentDefinitions
View the documentDirect conjunctive use
View the documentIndirect conjunctive use
close this folderChapter 16 - Pumped lift irrigation distribution
View the documentBackground
View the documentThe application of individually owned small pumping units
View the documentCentralized pumped-lift systems
close this folderChapter 17 - Technical and operational improvements in rehabilitation of irrigation projects
View the documentIntroduction
View the documentThe dam and reservoir
View the documentThe canal system
View the documentDrainage
View the documentIntroduction of high technology irrigation methods
close this folderChapter 18 - Ecological and riparian factors in irrigation development
View the documentIntroduction
View the documentEcological issues in groundwater development
View the documentSurface water development
View the documentRiparian issues
View the documentReferences
View the documentDistributors of world bank publications

Chapter 1 - Introduction

Most of the problems of smallholder irrigation involve not only technology but also sociological and economic factors. It is particularly unfortunate that practitioners in these specialties generally have a communication problem, even within the same agency. The answer to the frequently expressed plea for a more multi-disciplinary approach (usually aimed at irrigation engineers) is a better understanding by each specialty of the constraints which the others face in this area. The irrigation engineer needs to be familiar with the basic socio-economic problems of smallholder development, and the agro-economist and sociologist need to be better acquainted with the technical constraints on water distribution in circumstances of varying supply and demand.

In the following pages the principal factors entering into the design and operation of smallholder irrigation are discussed, with main emphasis on problems. Where the subject is contentious, which is often the case in this field, issues and options are presented. The targeted audience includes those working in the areas of irrigation engineering, agricultural economics, sociology, and development planning. As is appropriate to such a range of interest, the degree of technical detail has been kept to a minimum, with references added for those who wish further reading on particular subjects.

The aim is to define the problems, without necessarily acknowledging any obligation to present solutions. As yet, there are no entirely satisfactory solutions to many of the problems of smallholder irrigation. However, the available expedients are described, and the possible direction of further development is suggested.

The text draws upon two decades of experience in project development in South Asia, notably in India, in the service of international organizations. It is emphasized that the comments and opinions expressed are those of the author, and do not reflect the policies of any particular institution.