IRRIGATION DEVELOPMENT IN THE LOWER GWYDIR VALLEY

Chapter 1. Introduction 1.1 Project planning 1.2 Objectives of the study 1.3 Decision making and water resources 1.4 The study area 1.5 Approach taken in the study 1.5.1 Aspects examined 1.5.2 survey 1.5.3 Literature review 1.5.4 Synthesis Chapter 2. Conclusion 2.1 Synthesis 2.1.1 Development to date 2.1.2 Adoption of irrigation by Riparian landholders 2.1.3 Institutional constraints on irrigation development 2.1.4 Planning 2.1.5 Conflict 2.1.6 Future irrigation development 2.2 Conclusions 2.2.1 Irrigation development 2.2.2 Licensing policy 2.2.3 Water quality monitoring 2.2.4 Flood hazard zoning 2.2.5 Stream behaviour 2.2.6 Planning future development 2.2.7 Drainage basin authority Chapter 3. The environmental setting 3.1 Surface morphology 3.2 Drainage patterns 3.2.1 The Gwydir raft 3.3 Structural setting and geology 3.3.1 Structural framework and environment 3.3.2 General geology 3.3.3 Nature of cainozoic sediments 3.4 Soils of the Lower Gwydir Valley 3.4.1 Soils West of Moree 3.4.2 Soils of East Moree 3.4.3 Soils of North and South of Moree 3.5 Soils and irrigation potential 3.5.1 Soil structure stability 3.5.2 Soil salinity 3.5.3 Water-logging of soils 3.5.4 Soils suitable for irrigation 3.6 Lands of the Lower Gwydir Valley suitable for irrigation 3.6.1 Class 1 lands 3.6.2 Class 2 lands 3.7 Climate and water deficit 3.7.1 Rainfall 3.7.2 Temperature 3.7.3 Frosts 3.7.4 Sunshine 3.7.5 Wind 3.7.6 Evaporation and potential evapotranspiration 3.8 Water resources - Groundwater 3.8.1 Occurrence of aquifers 3.8.2 Piezometric surface and groundwater quality 3.8.3 Hydraulic yields 3.8.4 Groundwater quality 3.8.5 Suitability of groundwater for irrigation 3.8.6 Use of groundwater for irrigation 3.9 Water resources - Natural flow 3.9.1 Average annual run-off 3.9.2 Stream-flow characteristics 3.9.3 Periodicity of flow 3.9.4 Flood flows 3.10 The impact of flooding on irrigation development 3.10.1 January 1974 floods in the Gwydir 3.10.2 February 1976 floods in the Gwydir 3.10.3 Man-made structures and flooding 3.10.4 Changes in the distributary channels Chapter 4. Water resource development in the Lower Gwydir Valley 4.1 Early history 4.1.1 Groundwater 4.1.2 Surface water 4.2 Water storage construction 4.2.1 Early local interest 4.2.2 Site investigations 4.2.3 Copeton dam 4.3 Distribution of regulated flow 4.3.1 Plan A 4.3.2 Plan B 4.3.3 Opposition to the plan 4.3.4 Plan C 4.3.5 Continuation of conflict 4.4 The response of landholders 4.4.1 Survey findings 4.5 Current developments 4.5.1 The Gwydir raft 4.5.2 Water hyacinth 4.6 Synthesis Chapter 5. The agricultural setting 5.1 Resource appraisal and the land-use pattern of the Lower Gwydir Valley 5.1.1 The establishment of pastoralism 5.1.2 The growth of dry-land farming 5.1.3 Reappraisal of the role of water resources 5.2 Land use on Riparian properties 5.2.1 Location of Riparian properties 5.2.2 Size of Riparian properties 5.2.3 Enterprise on Riparian properties 5.2.4 Livestock enterprises 5.2.5 Crop enterprises 5.2.6 Relative importance of enterprises 5.3 The pattern of irrigation farming 5.3.1 Location of irrigated areas 5.3.2 Irrigation systems used 5.3.3 The growth of intensive irrigation farming 5.4 The scale of farming and grazing Chapter 6. The economics of irrigation 6.1 Project economics 6.1.1 The economic analysis 6.1.2 Assumptions underlying the analysis 6.1.3 Conclusion drawn in analysis of internal rate of return 6.1.4 Revision of the initial analysis 6.1.5 Conclusions drawn in revised analysis 6.2 Farm level economics 6.2.1 Variations in farm level economics 6.2.2 The farm level analysis 6.2.3 Border check irrigation systems 6.2.4 Centre pivot irrigation systems 6.2.5 Travelling irrigators 6.2.6 The model adopted for detailed analysis 6.2.7 Indirect costs 6.2.8 Opportunity costs 6.2.9 Direct costs 6.2.10 Relative profitability of irrigated and Dryland Enterprises 6.3 Implication arising from economic analyses Chapter 7. Decision making and the diffusion of irrigation agriculture 7.1 Decision making and diffusion processes 7.1.1 Decision making 7.1.2 Diffusion 7.2 Decision making and diffusion on Riparian properties 7.2.1 Research strategy 7.2.2 Comparison between groups 7.2.3 Personal attributes and situations of Decision makers 7.2.4 Review - Personal attributes and situations of decision makers 7.2.5 The decision environment 7.2.6 Information sources 7.2.7 Interpersonal communications networks 7.2.8 Review - The decision environment 7.2.9 Perception of and attitudes towards irrigation 7.2.10 Review - Perception of advantages and disadvantages of irrigation 7.3 Synthesis

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