Water-related adaptation to climate change

1. Water-related adaptation to climate change Alemseged Tamiru Haile (Ph.D.) 28 January 2014

2. Water scarcity • Physical scarcity: Not enough water. • Economic Scarcity: Not infrastructure to make water available to people • Both scarcities should be managed

3. Distribution of the percentage of area under irrigation Ample room for development

4. Climate change: change in the statistical properties of the climate system Fossil fuel, GW pumping, Land use change, Livestock Economy, Population, Technology Increased GHGE Anthropogenic Global warming Regional Changes Precipitation, Temperature, sea level Average condition, Variability, Extremes Impact Water, Agriculture, Energy, etc. Measures Mitigation, Coping, Adaptation Demand, Supply, Reservoir evaporation, Infrastructure damage Loss and damage Adapt to (i) less soil moisture and higher evaporation, (ii) Increased floods

5. Climate change adds new challenges

6. Source: Maartin de Wit and JacekStankiewicz www.scienceexpress.org/2March2006/Page1/10.1126/science1119929 African Scenarios – uncertainty is the keyword! Changes in surface water supply across Africa with Predicted Climate Change Increases and decreases: Small changes in temperature will see average river flows and water availability increase by 10-40% in some regions, while in others there will be a decrease of 10-30% Example: Blue Nile GCM Downscaling Precipitation Potential ET Runoff Actual ET 10 models show likely decrease of runoff 7 shows like increase of runoff

7. Climate change: Ethiopia • Studies show impact of CC on Sectors • By 2050 climate change could cause [Robinson et al., 2013]: • GDP to be 8–10 percent smaller than under a no-climate change baseline; • a two-fold increase in variability of growth in agriculture; • it would affect more severely the poor and certain parts of the country. • ADAPTATION IS THE PRIORITY

8. Barriers to adaptation (Based on Deressa et al., 2009 and Haile et al., 2014) • Farmers’ perception is there is long-term temperature and precipitation change • The least practiced adaptation strategy by HHs in the Nile basin is - Irrigation • Barriers to adaptation • Not knowing which kind of measures to take • Insufficient financial means • Shortage of labor

9. Water-related adaptation to climate change Despite its high productivity, irrigation is under growing pressure to reduce its environmental impact, including soil salinization and nitrate contamination of aquifers

10. Water-related adaptation to climate change • Inadequate storage leaves farmers vulnerable to CC • Store water for use in times of shortage • Continuum of storage: Reservoirs, Ponds and tanks, aquifer, soil moisture • The best option is to focus on • Combining a variety of storage types • Consider CC in planning, design and operation • Types of storage – tailored to specific conditions

11. Household Irrigation Technology (HIT) to transform Ethiopian agriculture sector • Agricultural intensification - “Save and Grow” - requires • Target households • Knowledge-based precision irrigation • Use of improved, drought tolerant varieties and management practices that save water • Reliable and flexible water application • Deficit irrigation • Estimates over the next 5 years indicate HIT could enable: • Over 500,000 ha could be irrigated - Doubling existing irrigation • >650,000 farming households to become agricultural entrepreneurs, • increasing family income and food security for almost 5 million Ethiopians • Adding $600 million USD and 30,000 jobs to the national economy

12. 7 major bottlenecks in the Household Irrigation sector of Ethiopia (Source: ATA) • Lack of readily available information on groundwater resource potential • to recommend technically feasible water lifting and saving technologies • Lack of data on high value crops for specific agroecology of the woredas • Absence of well-trained manufacturers to produce quality manual and mechanized HITs for smallholders, and lack of clear standards for HITs • Lack of reliable and interdependent HITs and other irrigation agriculture input supply chain • Absence of credit access to smallholder farmers to purchase HITs and other agriculture inputs during irrigation season • Smallholders are not getting the right training and advisory support on irrigated agriculture and the agriculture research system offers limited attention to high value crops • Frequent HIT failures and absence of locally available maintenance services or spare parts

13. Adaptive management of groundwater (AMGRAF) • Aim: to enable sustainable development of accessible (shallow) groundwater for small-scale irrigation • Assessment of groundwater resource and use • Development of tools for adaptive groundwater management • Research into scenarios of water management • Socio-economic: Livelihood impact, governance, institutions • Working definition of ‘accessibility’ • The depth to GW should be less than 30m

14. Adaptive management of groundwater (AMGRAF) Key findings include (eg): • There is some experience of GW use • GW resource is not evenly distributed among households • How to break Hard rocks to access water below 10-15 metres? • Overexploitation??? • Limitations to expanding use of irrigation include: water lifting mechanisms; wells dry out, scarcity of land; shortage of seedlings • If more irrigation available, would grow vegetable crops (onions, cabbage, pepper, garlic etc)

15. Spate irrigation “Floods are not always a hazard. They may also sustain aquatic life and riverine biodiversity, recharge aquifers, enrich soils and in some of the world’s poorest areas they are the main source of irrigation.” Global Water Partnership (2000) ‘Toward water security: a framework for action’ • Expansion of Spate Irrigation due to • Physical reasons • Lowlands: extensive flat, fertile surrounded by hills with high rainfall • The expansion of agriculture to the mountains • land degradation, reduced base flow, increased drought • Socio-economic reasons • Increased population in the lowland areas - increased demand • provides the livelihoods for economically marginal people

16. Spate irrigation Farmers observations over the last decade • Climatic factor for use of SI: • Reduced rainfall • Increased dry spells • Increased temperature • Challenges: • Unpredictable floods • Frequent damage of structures • Increased floods • Encourage SI How to properly to divert and manage the flood water for crop production?

17. IMPACT2C • Several reservoirs planned in Blue Nile • Target ensuring food security at households-E.g. Upper Beles:~20000 HHs • What is the link between these reservoirs? • Upstream-downstream trade-offs and opportunities • Hydropower, irrigation, environment • Water allocation • CC impact on • Demand and supply • Role of reservoirs - adaptation • Variability vs supply • Flood control • Water allocation

18. IMPACT2C • Quantifying projected impacts under 2°C warming • Global climate modeling (GCM), dynamic regional downscaling (RCM), and bias correction • Set of models and approaches can be used to assess impact • SWAT, HBV • WEAP, • CROPWAT, Mendlik and Gobiet (2013)

19. Conclusion • Better communicate CC uncertainty • Adapt to less soil moisture and increased floods • Invest in R&D to enhance adaptation • Accessibility is more important than potential – infrastructure • RWH (in-situ soil moisture maximization, ponds) • Shallow GW wells • Provide more and diverse physical storage infrastructure • Consider CC in planning, design & operation of storage schemes • “Save and Grow” • Irrigation technologies (treadle pumps, hand pumps, drip irrigation) and water saving

20. THANK YOU!!!