Note: Intro -- Contents -- 1 Preface: Rainwater-Smart Agriculture in Arid and Semi-arid Areas -- References -- General Approaches and Methods -- 2 Using Rainwater for Off-Season Small-Scale Irrigation in Arid and Semi-arid Areas of Sub-Saharan Africa: Key Working Principles and Best Practices -- Abstract -- 1 Introduction -- 2 Methodology -- 3 Key Working Principles of Off-Season Rainwater Harvesting Irrigation Management -- 3.1 Off-Season Rainwater Harvesting Irrigation Management -- 3.2 Advantages and Disadvantages -- 4 Best Practices for Collecting and Storing Rainwater for Off-Season Small-Scale Irritation -- 4.1 Upgraded Road Runoff On-Farm Ponds -- 4.2 Low-Cost Roof Catchments -- 4.3 Climate-Resilient Seasonal Sandy Streams and Cost-Efficient Groundwater Dams -- 4.3.1 Tapping into the Natural Capacity of Alluvial Shallow Reservoirs -- 4.3.2 Implementing Cost-Efficient Subsurface Dams -- 4.3.3 Implementing Smart Sand Storage Dams -- 4.4 Self-replicable Hillside Small Earth Dams -- 4.5 Irrigation-Smart Rock Catchment Systems -- 5 Best Practices on Reusing Rainwater for Off-Season Small-Scale Irrigation -- 6 Discussion -- 6.1 Constraints -- 6.2 Impacts -- 6.3 Cost-Efficiency -- 7 Conclusions -- Acknowledgements -- References -- 3 Fostering Food Security and Climate Resilience Through Integrated Landscape Restoration Practices and Rainwater Harvesting/Management in Arid and Semi-arid Areas of Ethiopia -- Abstract -- 1 Introduction -- 2 Characteristics of Tigray Region and Study Approach -- 2.1 Characteristics of Tigray Region -- 2.2 Study Approach -- 3 Results and Discussion -- 3.1 Major Trends in Sustainable Land and Water Management in Ethiopia -- 3.2 Key Impacts of Interventions in the Selected Sites -- 3.2.1 Impacts of LRWH Practices in the Abreha Weatsbeha Watershed -- 3.2.2 Impacts of LRWH Practices in the Sero Watershed. , 3.2.3 Impacts of LRWH Practices in the Dibdibo Watershed -- 3.2.4 Impacts of LRWH Practices in the Mariam Shewito Watershed -- 3.2.5 Impacts of LRWH Practices in the May Demu Watershed -- 3.3 Key Factors for Successful LRWH in Tigray -- 3.3.1 Technical Aspects -- 3.3.2 Community Engagement and Mobilizations -- 3.3.3 Institutional and Governance Issues -- 4 Conclusion and Recommendations -- Acknowledgements -- References -- 4 Towards Optimizing the Performance and Cost-Effectiveness of Farm Pond Technology for Small-Scale Irrigation in Semi-arid Farming Systems -- Abstract -- 1 Introduction -- 2 Methodology -- 2.1 Study Area and Spatial Coverage -- 2.2 Research and Development Process -- 2.3 Agro-hydrological Evaluation of Farm Pond -- 3 Results and Discussion -- 3.1 Quantification of Water Losses -- 3.2 Adaptive Research and Technology Development -- 3.3 Scaling Up Upgraded Farm Pond in Kenya -- 4 Conclusions -- References -- 5 The Promise of Flood-Based Farming Systems in Arid and Semi-arid Areas -- Abstract -- 1 Introduction -- 2 Results -- 2.1 Flood-Based Farming Systems -- 2.1.1 Floodplain Agriculture -- 2.1.2 Spate Irrigation -- 2.1.3 Inundation Canals -- 2.1.4 Depression Agriculture -- 2.2 Potential for FBFS Strengthening Through Knowledge Transfer -- 2.2.1 Water Distribution -- 2.2.2 Field Water Management -- 2.2.3 Groundwater Use and Mapping -- 2.2.4 Agronomic Practices -- 2.2.5 Multi-functional Use -- 2.2.6 Internal Governance -- 3 Discussion -- 4 Conclusion -- Acknowledgements -- References -- 6 Adaptations in Water Harvesting Technologies for Enhancing Food Security and Livelihood: A Multi-country Study in Sub-Saharan Africa -- Abstract -- 1 Introduction -- 2 Methodology -- 2.1 Study Area -- 2.1.1 Climatic Conditions -- 2.1.2 Water Harvesting Technologies -- 2.2 Methods -- 2.2.1 Case Study of Household Ponds in Ethiopia. , 2.2.2 Case Study of Ndiva Systems in Tanzania -- 2.2.3 Case Study of Combinations of Mechanized Zaï, Grass Strips and Bunds in Burkina Faso -- 3 Results -- 3.1 Household Ponds in Ethiopia -- 3.1.1 Current Status -- 3.1.2 Impact on Food Security and Livelihood -- 3.1.3 Pond Improvement: Use of Different Lining Materials -- 3.2 Ndiva Systems in Tanzania -- 3.2.1 Current Status -- 3.2.2 Impact on Food Security and Livelihood -- 3.2.3 Ndiva Improvement: The Lining of Conveyance Canals -- 3.3 Combinations of Mechanized Zaï, Grass Strips and Bunds in Burkina Faso -- 3.3.1 Current Status -- 3.3.2 Impact on Food Security and Livelihood -- 3.3.3 WHT Improvement and Impact on Soil Quality and Crop Yield -- 3.3.4 Costs and Benefits of Water Harvesting, Fertilization and Bunding (WTH+) -- 4 Discussion -- 5 Conclusions -- Acknowledgements -- References -- 7 Roads: Instruments for Rainwater Harvesting, Food Security and Climate Resilience in Arid and Semi-arid Areas -- Abstract -- 1 Introduction -- 2 Methodology -- 2.1 Study Area -- 2.2 Methods -- 3 Results -- 3.1 Collecting Water from Roads and Road Catchments -- 3.2 Adapting to the Road: Using Runoff and Water Flows Generated by Roads -- 3.2.1 Spreading Water from Road Surface and Culverts into Farmland -- 3.2.2 Harvesting Water from Culverts, Side Drains and Depressions -- 3.2.3 Gully Plugging for Recharge -- 3.2.4 Spring Capture -- 3.3 Adjusting the Road: Improving Road Design for Multiple Functions -- 3.3.1 Fords Combined with Sand Dams -- 3.3.2 Carefully Planning Road Alignment and Culvert Location -- 3.3.3 Permeable Road Foundations -- 3.4 Case Study in Tigray Region, Ethiopia -- 3.5 Case Study in Yemen -- 4 Discussion -- 4.1 Enhancing the Resilience of Roadside Communities -- 4.2 Impacts on Food Security and Poverty Alleviation -- 5 Conclusions -- Acknowledgements -- References. , Case Studies and Field Experiences -- 8 Fostering the Use of Rainwater for Off-Season Small-Scale Irrigation in Arid and Semi-arid Areas of Ethiopia -- Abstract -- 1 Introduction -- 2 Methodology -- 3 Results and Discussion -- 3.1 Rainwater Harvesting Technologies in Ethiopia -- 3.2 RWH and SSI Best Practices -- 3.3 Barriers to Adoption of RWH and SSI by the Smallholder Farmers -- 4 Conclusions and Recommendations -- Acknowledgements -- References -- 9 Fostering the Use of Rainwater for Off-Season Small-Scale Irrigation in Arid and Semi-arid Areas of Kenya -- Abstract -- 1 Introduction -- 1.1 Background -- 1.2 Objectives of the Study -- 1.3 The Principle of Rainwater Harvesting -- 2 Methodology -- 2.1 Study Area -- 2.2 Methods -- 3 Results -- 3.1 Rainwater Harvesting Systems in Kenya -- 3.1.1 Micro-catchment RWH Systems -- 3.1.2 Macro-catchment RWH Systems -- 3.1.3 In Situ RWH Systems -- 3.2 Rainwater Harvesting Irrigation Technologies in Kenya -- 3.2.1 On-farm Pond Systems -- 3.2.2 Earth Dams and Water Pans -- 3.2.3 Groundwater Dams (Sand Dams and Subsurface Dams) -- 3.2.4 Roof Water Catchment Systems -- 3.2.5 Rock Outcrop Catchment Systems -- 3.2.6 Flood Diversion and Spreading (Spate Irrigation) Systems -- 3.2.7 Small External Catchment Systems -- 4 Discussion -- 5 Conclusions and Recommendations -- Acknowledgements -- References -- 10 Rainwater Harvesting Options to Support Off-Season Small-Scale Irrigation in Arid and Semi-arid Areas of Zimbabwe -- Abstract -- 1 Introduction -- 2 Methodology -- 2.1 Study Area -- 2.2 Study Approach -- 3 Current RWHI Practices and Technologies in Zimbabwe -- 3.1 In-Field RWHI Systems -- 3.1.1 Infiltration Pits -- 3.1.2 Fanya Juu -- 3.1.3 Tied Contours -- 3.1.4 Dead-Level Contours -- 3.1.5 Ridging/Tied Ridging -- 3.1.6 Planting Basins -- 3.2 Ex Situ RWHI Systems -- 3.2.1 Roof Catchments -- 3.2.2 Rock Catchments. , 3.2.3 Small-Scale Surface Dams -- 3.2.4 Ground Catchment Systems -- Sand Dams -- 4 RWHI Technologies and Their Link to Small-Scale Irrigation Development -- 4.1 Ex Situ RWHI Systems and Small-Scale Irrigation -- 4.1.1 Rock and Roof Water Harvesting Structures and Small-Scale Irrigation -- 4.1.2 Small-Scale Surface Dams and Small-Scale Irrigation -- 4.1.3 Groundwater Systems and Small-Scale Irrigation -- 4.2 Challenges of RWHI Upscaling in Zimbabwe -- 5 Conclusions and Recommendations -- Acknowledgements -- References -- 11 Improving the Efficiency of Runoff Pond System for Supplementary Irrigation in Arid and Semi-arid Areas of Kenya -- Abstract -- 1 Introduction -- 2 The Advent of Trapezoidal Runoff Ponds in Kenya -- 3 Assessment and Improvement of Efficiency for the Runoff Pond Components -- 3.1 Conveyance Mechanisms -- 3.1.1 Road Channels and Waterways -- 3.1.2 The Mini-Wetlands -- 3.1.3 The Automated Silt Trap -- 3.2 Storage Mechanisms -- 3.3 Abstraction and Application Mechanisms -- 3.3.1 The Bucket and Rope -- 3.3.2 The Rope-and-Washer Pump -- 3.3.3 The Brazilian Pump -- 3.3.4 The MoneyMaker Pumps -- 4 Conclusion -- References -- 12 Low-Tech Irrigation Strategies for Smallholder Vegetable Farmers in Kenya -- Abstract -- 1 Introduction -- 2 Material and Methods -- 2.1 Study Area -- 2.2 Data Collection in Kenya -- 2.3 Green River Principle -- 3 Rainwater Management Methods Used in Kajiado -- 4 Resource Efficiency of GRP -- 5 Cost Efficiency of GRP -- 6 Local Adoption of Rainwater Smart Management and Irrigation -- 7 Outlook -- 8 Conclusions -- References -- 13 Rainwater Harvesting Irrigation-A Strategic Measure for Integrated Rural Development in the Dry Mountainous Areas of Gansu Province, China -- Abstract -- 1 Introduction -- 2 Description of the RWH Irrigation Systems -- 2.1 The Rainwater Catchment -- 2.2 Rainwater Storage Tank. , 2.3 High-Efficiency Irrigation Equipment.