CGIAR Initiative on Fragility, Conflict, and Migration Technical Report Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges in Dolo Ado and Bokolmayo Districts, Somali Regional State, Ethiopia Tewodros T. Assefa, Meron Teferi Taye, Girma Yimer Ebrahim and Sandra Ruckstuhl October 2024 Author affiliations Dr. Tewodros T. Assefa, Associate Professor, Bahir Dar University, Bahir Dar, Ethiopia. (ttaffese@gmail.com) Dr. Meron Teferi Taye, Researcher – Transitioning Landscapes, International Water Management Institute (IWMI), Addis Ababa, Ethiopia. (meron.taye@cgiar.org) Dr. Girma Yimer Ebrahim, Researcher – Hydrogeology and Water Resources, IWMI, Addis Ababa, Ethiopia. (g.ebrahim@cgiar.org) Dr. Sandra Ruckstuhl, Senior Researcher, IWMI, Giza, Egypt. (s.ruckstuhl@cgiar.org) Suggested citation Assefa, T. T.; Taye, M. T.; Ebrahim, G. Y.; Ruckstuhl, S. 2024. Status report on water resources availability, accessibility and technology needs for addressing water security challenges in Dolo Ado and Bokolmayo districts, Somali Regional State, Ethiopia. Colombo, Sri Lanka: International Water Management Institute (IWMI). CGIAR Initiative on Fragility, Conflict, and Migration. 28p. Acknowledgements This work was supported by the Norwegian Government under the project titled ‘Learning Support for a Sub-Saharan Africa Multi-Country Climate Resilience Program for Food Security,’ and by the donors who fund the CGIAR Research Initiative on Fragility, Conflict, and Migration (FCM), through their contributions to the CGIAR Trust Fund: https://www.cgiar.org/funders/ The authors thank Dr. Wolde Mekuria (Senior Researcher - Environment and Development, IWMI, Addis Ababa, Ethiopia), Dr. Darshini Ravindranath (Research Group Leader - Climate Policies, Finance and Processes [CPFP], IWMI, New Delhi, India), and Daniel Ocom (Resilience and Livelihood Specialist, World Food Programme [WFP], Dolo Ado, Somali Region, Ethiopia) for reviewing and providing comments on earlier versions of this report. The authors are also grateful to WFP staff (Abdiwahid Ibrahim, Mohamed Mohamud and Asho Gedi) for supporting and facilitating the fieldwork. CGIAR Initiative on Fragility, Conflict, and Migration The CGIAR Initiative on Fragility, Conflict, and Migration aims to enhance the resilience of food, land, and water systems in fragile and conflict-affected settings, where migration-related challenges are prevalent. By taking a systems approach and working in partnership with local stakeholders, the initiative seeks to generate evidence to inform effective policies and programs that promote social and gender equity, climate resilience, conflict mitigation, and peace building in these settings. Learn more about the initiative here: https://www.cgiar.org/initiative/fragility-conflict-and-migration/ Cover photo: Production of annual and pernnial crops using irrigated agriculture, Bokolmayo, Somali Region, Ethiopia (Photo: Wolde Mekuria). Disclaimer This publication has been prepared as an output of the CGIAR Initiative on Fragility, Conflict, and Migration and has not been independently peer-reviewed. Responsibility for opinions expressed and any possible errors in the publication lies with the authors and not the institutions involved. The boundaries and names shown in the maps and the designations used do not imply official endorsement or acceptance by IWMI, CGIAR, our partner institutions, or donors. mailto:ttaffese%40gmail.com?subject= mailto:meron.taye%40cgiar.org?subject= mailto:g.ebrahim%40cgiar.org?subject= mailto:s.ruckstuhl%40cgiar.org?subject= https://www.cgiar.org/funders/ https://www.cgiar.org/initiative/fragility-conflict-and-migration/ Contents List of Figures ................................................................................. 4 List of Tables ................................................................................... 4 Abbreviations and Acronyms ...................................................... 5 Summary 6 1. Introduction 7 2. Study Area Description 8 3. Materials and Methods 10 3.1. The Framework of the Study ................................................ 10 3.2. Description of the Hydrologic Model ................................ 11 3.3. Data and Sources ................................................................. 12 3.4. Hydrologic Model Setup ..................................................... 13 3.5. Model Performance Evaluation Criteria ........................... 14 3.6. Assessing Water Availability in the Dolo Ado and Bokolmayo Districts .................................................................... 14 4. Results and Discussion 15 4.1. Model Parameter Sensitivity Analysis ............................... 15 4.2. Model Calibration and Validation ...................................... 16 4.3. Hydrologic Response of Dolo Ado and Bokolmayo Districts ......................................................................................... 17 4.4. Water Availability ................................................................. 19 4.5. Water Accessibility ............................................................... 21 4.6. Technology Needs ...............................................................21 5. Conclusion and Recommendations 22 References 23 Ph o to g ra p hy b y W o ld e M ek ur ia October 2024 | Status Report on Water Resources Availability, October 2024 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | 3 List of Figures List of Tables List of Figures Figure 1. Location of Dolo Ado and Bokolmayo districts within the Genale Dawa River Basin. ....................................................... 8 Figure 2. Spatial maps of the Dolo Ado and Bokolmayo districts in the Somali Regional State of Ethiopia: Land use (A), slope classes (B), (C) soil texture, and (D) mean annual rainfall, from 1981 to 2023. ......................................................................... 8 Figure 3. Mean monthly rainfall (A), and annual rainfall (B) for the Dolo Ado and Bokolmayo districts based on The Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS), 1981–2023. .................................................................... 9 Figure 4. Deviation of annual rainfall from the long-term mean of the baseline period of 1981–2022 based on CHIRPS rainfall data. .............................................................................................. 10 Figure 5. Framework to assess the status of water resource availability, accessibility, and technology needs in the Dolo Ado and Bokolmayo districts. .................................................... 11 Figure 6. Sub-watersheds of the Halwen sub-basin and districts in the Genale River Basin. ............................................ 13 Figure 7. Comparison of monthly observed and simulated stream flow during the calibration (1985 to 1987) and validation (1988 to 1989) periods. ............................................. 17 Figure 8. Hydrologic responses of Dolo Ado and Bokolmayo districts. PCP, ET, Q, PERC, and SSF were precipitation, evapotranspiration, surface runoff, percolation, and sub- surface flow, respectively. All units are in mm. ........................ 18 Figure 9. Water availability; surface water availability from streamflow and irrigation water availability for Dolo Ado and Bokolmayo districts. ................................................................... 19 Figure 10. The long-term (2004–2023) mean monthly recharge. ......................................................................................20 Figure 11. Locations of groundwater wells, depth to groundwater spatial map during wet season and the Dawa transboundary aquifer. ...............................................................20 List of Tables Table 1. Data types and their sources used for water availability assessment. ............................................................. 12 Table 2. Calibration parameters for the SWAT model, their descriptions, and parameter space used in SWAT-CUP automated calibration and sensitivity analysis. ...................... 13 Table 3. Parameter sensitivity analysis result for Halwen sub- basin. ............................................................................................ 15 Table 4. Parameter sensitivity analysis results for Halwen sub- basin. ............................................................................................ 16 4 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | October 2024 Abbreviations and Acronyms CFSR .......................................Climate Forecast System Reanalysis CHIRPS ...................Climate Hazard Group InfraRed Precipitation with Station Data DEM ..............................................................Digital Elevation Model ECMWF ................European Centre for Medium-Range Weather Forecasts ERA5.......................... Atmospheric Reanalysis for Global Climate (Fifth Generation) ESA ........................................................... European Space Agency FAO ..............................Food and Agriculture Organization of the United Nations FDC ...................................................................Flow Duration Curve HRUs ......................................................Hydrologic Response Units IDPs ...................................................... Internally Displaced People SWAT .............................................Soil and Water Assessment Tool SWAT-CUP ..............Soil and Water Assessment Tool Calibration and Uncertainty Program USGS .......................................United States Geographical Survey UNHCR ...........United Nations High Commissioner for Refugees Q90 ..................Flow in the stream that was equaled or exceeded by the mean monthly flow 90% of the time. WFP ............................................................World Food Programme Ph o to g ra p hy b y W o ld e M ek ur ia October 2024 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | 5 Summary Adapting to and mitigating the impacts of extreme weather and climate change in fragile environments requires addressing key questions on the status of water availability, accessibility, and technology needs. The primary goal of this research is to provide comprehensive data and actionable insights to support organizations such as the World Food Programme (WFP) and other stakeholders in developing effective strategies for water management, enhancing resilience, and ensuring water access for host communities, refugees, and internally displaced people (IDPs). This study focused on the Dolo Ado and Bokolmayo districts of Ethiopia, which are parts of the Genale Dawa River basin and the Somali Regional State that are categorized as fragile environments with a high degree of sensitivity to climate extremes. To quantify the water availability in the districts, a hydrologic model, Soil and Water Assessment Tool (SWAT), was set up and calibrated at watershed scale. Using this calibrated model, the surface water and groundwater availability were estimated. Surface water availability for Dolo Ado and Bokolmayo districts is estimated to range from 26 million cubic meters (MCM) in February to 843 MCM in May. From the hydrological modeling, it is evident that surface runoff is the lowest water balance component for the districts. This indicates that the major water sources in Dolo Ado and Bokolmayo are derived mainly from the rivers passing adjacent to the districts. Communities living close to the rivers have more access to water, with the challenge of the high cost of pumping river water for domestic and irrigation use. The water for irrigation was quantified from the low flow of streamflow simulation and annual recharge in the districts. After considering the environmental flow, 0.5 to 14.5 MCM can be considered available for irrigation in dry and wet months, respectively. Water availability for irrigation from recharge estimates can range from 1.1 MCM in September to 94.5 MCM in December. With the available water, the potential irrigable area is estimated to be around 5,900 ha and 5,300 ha for two irrigation seasons common in the districts. The results show that there is more surface water potential — mainly from the river — for irrigation in the districts compared to groundwater sources from the shallow aquifers. The status of water accessibility and technology needs was evaluated using a review of the literature and information obtained from stakeholder consultations. Existing challenges in water accessibility in the districts include inadequate infrastructure for water storage, damage to irrigation canals, seasonality of ponds, salinity of groundwater, inadequate access to clean water, and the high cost associated with pumps, fuels, and spares. Appropriate technology interventions are required to address the challenges in water availability and accessibility by the local host communities, refugees, and IDPs. The potential water users in the districts are farmers, herders, households, and the ecosystem. Integration of innovative technologies and practices is key to supporting resilience against climate extremes. This study recommends the need to switch from basin irrigation to water-saving technologies such as drip and sprinkler irrigation systems. Additionally, diversification of the source of water supply is needed, such as the conjunctive use of groundwater and surface water, and the use of different water sources. Investing in the rehabilitation and maintenance of existing water infrastructure, such as wells, boreholes, and irrigation canals, is essential to improve water availability and distribution. The promotion of efficiency through water- saving technologies is vital, using efficient water application techniques through wetting front detector tools and Chameleon soil water sensors. Emphasis should be given to maximizing productivity while conserving water through the adoption of innovative cropping patterns and agronomic practices. This includes choosing crop varieties that are drought-resistant as well as those that are not water intensive. Watershed management practices must be promoted to increase the recharge of water into groundwater. This includes reforestation, soil and water conservation measures, and proper land-use planning and management. Integrated water storage mechanisms will bridge water availability during dry seasons and droughts and therefore should be promoted for these districts. In addition, promoting community-based initiatives and fostering stakeholder collaboration can empower local communities to actively engage in sustainable water management practices and build resilience to future water-related challenges. 6 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | October 2024 1. Introduction 1 https://www.worldbank.org/en/news/feature/2021/09/13/millions-on-the-move-in-their-own-countries-the-human-face-of-climate-change 2 UNHCR, August 31, 2021. 3 https://reliefweb.int/report/ethiopia/financial-services-market-assessment-dollo-ado-and-bokolmayo-refugee-camps-somali 4 CSA, July 2023. 5 CSA, July 2020. Climate change and weather extremes pose significant challenges worldwide, particularly for vulnerable communities such as refugees, internally displaced people (IDPs), and their host communities. According to the World Bank1, increasing intensity and frequency of extreme weather events — abnormally heavy rainfall, prolonged droughts, desertification, environmental degradation, sea-level rise, cyclones, etc. — will cause 86 million internal climate migrants by 2050 in sub-Saharan Africa alone. Such persons typically live in climate “hotspots” that lack the resources to adapt to an increasingly hostile environment (UNHCR n.d.). The African continent faces increasing occurrence of prolonged droughts and flooding after drought, threatening agricultural productivity and livelihoods as crops and livestock struggle to survive harsh climate conditions (Haile et al. 2019; Ibe and Amikuzuno 2019; Nkomo et al. 2006). This is one of the reasons forcing the migration of large groups of people. Ethiopia in particular faces complex obstacles at the crossroads of population movement and growth and climate change immersing pressure on water and food security across the country (Giller 2020; Shankar 2018). With the alarming rise in population and hosting over 900,000 refugees countrywide (Betts et al. 2019), the demand for food and drinking water is escalating rapidly (Walker 2016). The adverse climate effects intensify vulnerabilities in regions like Somali Regional State, which is naturally hot and dry. The region experiences drought that jeopardizes agricultural productivity, livestock death and economic stability of mainly host communities (Destrijcker et al. 2023; Sultan and Gaetani 2016). With the adverse effects on the economy, there is an impact on the job availability for refugees rendering them vulnerable to the changes. The pastoralist community with limited economic opportunities is particularly vulnerable to these changes in a climate which becomes too hot and dry or too wet at unexpected times (Leal Filho et al. 2020; Serdeczny et al. 2017). The Dolo Ado and Bokolmayo districts of the Somali Regional State of Ethiopia host 172,384 refugees2; the communities are vulnerable to the impacts of climate change [United Nations High Commissioner for Refugees (UNHCR) 20213]. Water scarcity and environmental degradation are the main challenges in the districts (Shigute et al. 2022). In Ethiopia, refugees have the right by law to engage in wage- earning employment (UNHCR n.d.). However, in these two districts, the refugees and host communities are deprived of resources and have limited economic opportunities (PfR and UN Environment 2020). The population of Dolo Ado and Bokolmayo districts are 170,3174 and 90,0005, respectively. Thus, the proportion of refugees to host communities is about 66%. The failure of consecutive rainy seasons aggravates water scarcity, crop production, livestock conditions, and livelihoods (Krampe et al. 2020; Mekuria 2022; Mohamed 2017). This situation adversely affects both refugees and host communities. To effectively mitigate the impacts of extreme weather in Dolo Ado and Bokolmayo districts through informed decisions, assessing the status of water availability, water accessibility, and technology is imperative. The main objective of this study was, therefore, to assess the status of water availability, accessibility, and technology needs for Dolo Ado and Bokolmayo districts through the support from the World Food Programme (WFP). Thus, the following key questions are addressed in this report: { What is the status of water resources availability in the districts? This covers surface water and groundwater availability. { What is the current accessibility of water for livelihood? With a focus on irrigation water availability. { What kind of technology needs are there to address water security challenges? At the district level, the water available for various uses often comes from the upstream catchment (Figure 1). Similarly, distractive flooding originates from the uplands of the catchment. This indicates the need for watershed or basin-level modeling to understand the underlying hydrology. Such studies, which are not available at the district level, would help to examine the potential expansion of smallholder irrigated agriculture from dry season streamflow and annual recharge. This study fills the gap by examining water availability, combining surface and groundwater sources for various uses in the districts. It also enables us to understand where most of the water comes from during flooding. The findings from this study would serve as a baseline to decision-makers on water resource planning, and humanitarian organizations that plan to focus more on resilience building, disaster risk management and the sustainable use of water resources. The findings of this study could be a starting point for further research on optimized water use that leads to improved water management and agricultural productivity on a larger scale. October 2024 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | 7 2. Study Area Description This study was conducted in Dolo Ado and Bokolmayo districts, located in the Genale Dawa River Basin (Figure 1). Geographically the districts are located between 3O57’ and 4O09’ N and 40O48’ and 42O06’ E. Based on a 30 m SRTM digital elevation model (DEM), elevation in the districts ranges from 169 m to 974 m above sea level. The two districts cover an area of 8,135 km2. The land cover of Dolo Ado and Bokolmayo districts (Figure 2A) is dominated by shrubland (~78%) followed by grassland (~20%). The slope of the two districts (Figure 2B) is mostly between 2 to 8% (~45.2%). About 34% and 21% of these districts exhibit below 2% and above 8% slope, respectively. The entire districts are covered by loam texture and with four soil types — Fluvisols, Gypsisols, Leptosols, and Solonchaks (Figure 2C). Loam soils are under hydrologic soil groups C and D (de Trincheria et al. 2017), which are characterized by low infiltration rates and high runoff. The spatial mean annual rainfall over the districts from 1981 to 2023 varied between 219 mm at the Somalia border and 381 mm upstream of the districts (Figure 2D). Livelihood in the region depends on pastoralism and mixed farming, crop cultivation, and livestock (Shigute et al. 2023); it is nearly 80% pastoralist in the Dolo Ado and Bokolmayo districts (Ugas and Eggenberger 1999). The average land holding size in the districts is 1.5 ha with few people practicing irrigation from rivers (Tekola 2016). The dominant irrigated crops in the districts are maize, onion, tomato, pepper, cabbage, mango, and banana (Tekola 2016). Figure 1. Location of Dolo Ado and Bokolmayo districts within the Genale Dawa River Basin. Source: Authors’ creation. Figure 2. Spatial maps of the Dolo Ado and Bokolmayo districts in the Somali Regional State of Ethiopia: Land use (A), slope classes (B), (C) soil texture, and (D) mean annual rainfall, from 1981 to 2023. Source: Authors’ creation. 8 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | October 2024 The temporal district’s average annual rainfall variation is from 106 mm to 609 mm with a mean value of 273 mm. The monthly rainfall has a bimodal pattern with the highest rainfall occurring in April and the second highest in October (Figure 3A). The highest annual rainfall, 585 mm, occurred in 2019. No considerable annual trends were observed (Figure 3B). R ai nf al l ( m m ) 40 20 60 100 140 160 0 80 120 180 Month (A) Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec R ai nf al l ( m m ) 200 100 300 500 0 400 600 700 Year (B) 19 81 19 82 19 83 19 84 19 85 19 86 19 87 19 88 19 89 19 90 19 91 19 92 19 93 19 94 19 95 19 96 19 97 19 98 19 99 20 00 20 01 20 03 20 04 20 02 20 05 20 06 20 07 20 08 20 09 20 10 20 11 20 12 20 13 20 14 20 15 20 16 20 17 20 18 20 19 20 20 20 21 20 22 20 23 Figure 3. Mean monthly rainfall (A), and annual rainfall (B) for the Dolo Ado and Bokolmayo districts based on The Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS), 1981–2023. The deviation of annual rainfall from the long-term mean value (Figure 4) showed that most of the years (60%) are dry. There are more consecutive dry years; however, there is no consistent deviation with the cyclical pattern during both dry and wet years. The highest above average rainfall was observed in 1997 followed by the years 2019 and 2006 while the highest below average rainfall occurred in 1984 followed by 2001 and 1983. This variability highlights the district’s vulnerability to irregular rainfall patterns, emphasizing the need for adaptive strategies to manage water resources effectively. October 2024 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | 9 D ev at io n fr o m lo ng -t er m m ea n an nu al R ai nf al l ( m m ) -200 -100 100 300 0 200 400 Year 19 81 19 82 19 83 19 84 19 85 19 86 19 87 19 88 19 89 19 90 19 91 19 92 19 93 19 94 19 95 19 96 19 97 19 98 19 99 20 00 20 01 20 03 20 04 20 02 20 05 20 06 20 07 20 08 20 09 20 10 20 11 20 12 20 13 20 14 20 15 20 16 20 17 20 18 20 19 20 20 20 21 20 22 20 23 Figure 4. Deviation of annual rainfall from the long-term mean of the baseline period of 1981–2022 based on CHIRPS rainfall data. 3. Materials and Methods 3.1. The Framework of the Study In the areas where frequent drought and flash floods occur, effective mitigation efforts from water-related risks hinge upon a comprehensive understanding of the underlying hydrology at the watershed level. The floods in the districts originate from the upstream watershed, flowing to downstream areas that are commonly affected. Similarly, the water sources for multiple uses in the downstream areas (i.e., the study districts) originate from the upstream areas. Therefore, a thorough understanding of the hydrological process is indispensable to devising effective mitigation strategies. It enables local authorities to anticipate, prepare, and respond to droughts and floods in a manner that considers the interconnectedness of upstream and downstream areas. The framework used to assess the status of water resource availability, accessibility, and technology needs to address water scarcity challenges in Dolo Ado and Bokolmayo districts is given in Figure 5. A hydrologic model was used at the sub-basin level to understand the underlying hydrology and estimate water availability and localize results to the district level. The SWAT model was chosen to analyze the underlying hydrology in the districts and beyond at the watershed scale. The SWAT model is commonly used to evaluate the impacts of various management practices on hydrology (Arnold et al. 2012; Gassman et al. 2005). It uses inputs such as weather, DEM, soil, and land uses to simulate the hydrology of a catchment. Streamflow data was used to calibrate the hydrology model. Literature values on water balance components were used to compare the results. The SWAT-Calibration and Uncertainty Program (SWAT- CUP) was used to calibrate the model until a reasonable performance was obtained. The hydrologic balance of the districts was estimated by identifying dominant hydrologic response units (HRUs), in the district and taking its equivalent water balance proportions in the catchment. Surface water availability in the districts was quantified based on the Genale Dawa River observed streamflow. Surface water availability was quantified using low-flow analysis on a monthly basis after deducting environmental flow, which can be considered to be the water available for food production. Similarly, water availability for irrigation from recharge to the groundwater was estimated after considering the ecosystem and other consumptive water uses. To understand the status of water accessibility and the associated technology needed to access the water, a literature review was conducted and used in conjunction with the output from a stakeholder consultation workshop. The stakeholder consultation workshop output was integrated into the review to gain insights into effective strategies for improving water accessibility and identifying appropriate technologies. 10 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | October 2024 Hydrological modeling using SWAT Stream flow data Surface: Environmental flow Stakeholder consultation Review Recharge: Ecosystem and other consumptive uses Status of water accessibility, and technology needs Literature Weather DEM Soil Land use Water availability for irrigation Status of water availability Model calibration using SWAT-CUP Model performance evaluation Figure 5. Framework to assess the status of water resource availability, accessibility, and technology needs in the Dolo Ado and Bokolmayo districts. Source: Authors’ creation. 3.2. Description of the Hydrologic Model SWAT model is a globally recognized hydrological model used for water resource assessment (Jayakrishnan et al. 2005; Krysanova and White 2015) and evaluation of watershed management practices such as irrigation (Uniyal et al. 2019). In SWAT, a watershed is divided into sub-basins based on topography, and then each sub-basin is conceptually divided into HRUs, based on slope, soil, and land use (Worqlul et al. 2018). The HRUs have a unique combination of land use, soil, and slope. SWAT model simulates the soil water content, surface runoff, evapotranspiration, sediment yield, plant growth, and the impacts of management practices at the HRU level and then aggregated at the sub-basin level (Neitsch et al. 2011). The general water balance equation used in SWAT is shown in Equation (1). A detailed description of the model conceptual framework and simulation strategies can be found in (Arnold et al. 2012; Arnold et al. 1998). SWt = SWt−1 + ∑1(Pi − Qsurf, i − ETi − Qloss, i − Qgw, i ) ..... (1) t October 2024 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | 11 Where, SWt-1, Pi, Qsurf,i, ETi, Qloss,i, Qgw,i are soil water content above the wilting point at the end of day t, amount of precipitation on the day i, the daily amount of surface runoff, evapotranspiration, percolation into the deep aquifer, and lateral sub-surface flow, respectively. All components are estimated in the units of mm. 3.3. Data and Sources Hydrological modeling using SWAT relies on a wide range of time series and spatial data to understand and simulate the various components of the hydrological cycle (Arnold and Fohrer 2005). The spatial data inputs include the DEM, soil characteristics, and land use/cover information. The time series data inputs are the weather data, which include precipitation, maximum and minimum air temperature, relative humidity, wind speed, and solar radiation. In addition, the model requires streamflow records, groundwater level measurements, evapotranspiration, or combinations of these data to calibrate and validate the various hydrological components. Remote sensing data such as satellite imagery, satellite rainfall, and temperature reanalysis enable hydrological studies to create a comprehensive model with reasonable accuracy for sustainable water resource management (Abate et al. 2023; Mebrie et al. 2023). This study used observed streamflow records at Halwen station for SWAT model calibration and validation of the hydrological water balance. Table 1 presents the data types and their sources used to set up the SWAT model and calibrate/validate it for hydrology. Table 1. Data types and their sources used for water availability assessment. Data Source Resolution (m/time) Land use and land cover European Space Agency (ESA), land covers 2020 10 Soil characteristics Food and Agriculture Organization of the United Nations (FAO), through ISRIC-World Soil Information 250 Digital Elevation Model (DEM) United States Geographical Survey (USGS), 2000 30 Rainfall (mm) Climate Hazard Group InfraRed Precipitation with Station data (CHIRPS) 5,000 Temperature (ºC) European Centre for Medium-Range Weather Forecasts (ECMWF), Atmospheric Reanalysis for Global Climate (ERA5) 24,000 Relative humidity, solar radiation, wind speed Climate Forecast System Reanalysis (CFSR) 55,000 Stream flow Data Basin Development Authority of Ethiopia Daily Groundwater wells Genale Dawa River Basin Integrated Resource Development Master Plan Point data The Climate Hazard Group InfraRed Precipitation with Station data (CHIRPS) rainfall, and the fifth generation European Centre for Medium-Range Weather Forecasts (ECMWF) and Atmospheric Reanalysis for Global Climate (ERA5) temperature datasets were used due to the inaccessibility of ground meteorological station records. CHIRPS combines satellite infrared data with ground-based rain gauge observations, blending the strength of both sources. It offers long-term rainfall data with a high spatial resolution of 5 km (Cepeda Arias and Cañon Barriga 2022; Gao et al. 2018). ERA5 assimilates a vast amount of observation data — including satellite measurements and weather station data — into the model to produce reliable temperature estimates. The ERA5 long-term temperature estimates are with a spatial resolution of 24 km. Both CHIRPS rainfall and ERA5 temperature have undergone extensive validation against independent observation data and have shown promising results in various regions worldwide (Dinku et al. 2018; Gleixner et al. 2020). In addition, the Climate Forecast System Reanalysis (CFSR) datasets were used as weather generators in SWAT to simulate other weather variables such as wind speed, relative humidity, and solar radiation. Likewise, the CFSR dataset has undergone thorough validation against ground-based observation and showed reasonable performance (Dile and Srinivasan 2014). At the same time, it is worth noting that no reanalysis product is perfect, and limitations and uncertainties do exist (Condom et al. 2020; Thejll and Gleisner 2015). 12 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | October 2024 3.4. Hydrologic Model Setup The hydrological modeling setup was started by preparing the input datasets such as weather, DEM, soil, and land use based on the SWAT format. Given the river outlet location at Halwen station, the 30 m DEM was used to delineate the watershed, generate drainage patterns, and associated topographic characteristics. Land use and soil data in combination with DEM were used to create hydrologic response units. Weather data such as rainfall, temperature, wind speed, relative humidity, and solar radiation, from 1981 to 2023, were supplied to the model to set up a hydrologic model using SWAT. Observed streamflow data, from 1984 to 1989, was used to calibrate the hydrology, and the Genale Dawa River Basin Master Plan (Ministry of Water Resources Ethiopia 2005) were used to compare model results. The simulation period was divided into three; warm-up (1981 to 1984), calibration (1985 to 1987), and validation periods (1988 to 1989), based on stream flow data availability. During the SWAT model setup, the Halwen sub-basin was classified into 7 sub-watersheds and 86 HRUs (Figure 6). To quantify the hydrologic responses of the districts, the dominant HRU was considered. The dominant HRUs of the districts are identified by manually assessing soil, land use, and slope maps in GIS. An HRU with loam soil texture, between 2% to 8% landscape slope, and dominantly covered by shrub land was found to be the dominant HRU. The same HRU was identified from sub-watershed ‘1’ to quantify water balance components for the district by re-running the model with district weather. The weather was extracted by the boundary of the districts. This study used 16 calibration parameters for the SWAT model based on literature and expert opinion. The description of the parameters and their ranges are given in Table 2. A global sensitivity analysis was applied to identify the parameters that significantly influence the streamflow. In the global sensitivity analysis, all parameters are allowed to change at the same time followed by the estimation of the standard regression coefficient. The t-stat and p-value were used to evaluate the significance of the relative sensitivity. A p-value close to zero and a relatively small absolute value of t-stat represent higher significance (Nazari-Sharabian et al. 2020). Figure 6. Sub-watersheds of the Halwen sub-basin and districts in the Genale River Basin. Source: Authors’ creation. Table 2. Calibration parameters for the SWAT model, their descriptions, and parameter space used in SWAT-CUP automated calibration and sensitivity analysis. Parameter Name Parameter range Soil Conservation Service (SCS) runoff curve number CN2.mgt ±0.35 Soil evaporation compensation factor ESCO.hru 0.01 – 1.0 Average slope length SLSUBBSN.hru ±0.5 Manning’s “n” value for overland flow OV_N.hru 0.01 – 0.3 Surface runoff lag time SURLAG.bsn 0.0001 – 1.0 Depth to impervious layer for modeling perched water tables DEP_IMP.hru 0.0 – 6000 Base flow alpha factor (days) ALPHA_BF.gw 0.0 – 1.0 Threshold depth of water in shallow aquifer required for return flow to occur (mm) GWQMN.gw 0.0 – 5000 Groundwater “revap” coefficient GW_REVAP.gw 0.02 – 0.2 Manning’s “n” value for the main channel CH_N(2).rte 0.01 – 0.3 Average slope of main channel CH_S(2).rte ±0.5 Continued > October 2024 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | 13 Parameter Name Parameter range Available water capacity of the soil layer SOL_AWC.sol ±0.25 Depth from soil surface to bottom of layer SOL_Z.sol ±0.25 Saturated hydraulic conductivity SOL_K.sol ±0.25 Average slope of tributary channels CH_S(1).sub ±0.5 Manning’s “n” value for the tributary channels CH_N(1).sub 0.001 – 0.3 3.5. Model Performance Evaluation Criteria The performance of the calibrated SWAT model flow and predicted flow during the validation period were evaluated using commonly used statistics, R-squared (R2), and Nash- Sutcliff Efficiency, NSE. R-squared in Equation (2) varies from zero to one, where a value of one represents a perfect correlation and the reverse refers to no correlation. NSE in Equation (3) varies from negative infinity to one, where a value of one represents a perfect model simulation of the observed flow. A negative NSE value refers to the average of observed time series performing better than the model predictions. √[n(∑ Qobs(i)) 2 − (∑ Qobs(i) 2] [n(∑ Qsim(i) 2) − (∑ Qsim(i) 2] n ∑ Qobs(i) Qsim(i) − (∑ Qobs(i))(∑Qsim(i))R 2= 2( ) ..... (2) ∑i=1 (Qsim(1) − Qobs(i))2 ∑i=1 (Qobs(1) − Qobs(i))2 −NSE = 1− ..... (3) n n 3.6. Assessing Water Availability in the Dolo Ado and Bokolmayo Districts The SWAT model was used to simulate streamflow (last 20 years) from 2004 to 2023 using the obtained optimized parameters. This was done by providing up-to-date weather data, to derive the recent long-term average hydrology of the Halwen sub-basin. The hydrological responses used to characterize the districts include evapotranspiration, catchment water yield, surface runoff, percolation, and soil moisture. The simulated flow was considered the source of surface water for the districts; groundwater availability was estimated based on recharge to groundwater in the districts. Flow Duration Curve (FDC) was used to identify 90-percentile flow (Q90) available for irrigation during the dry season. The long-term monthly flows, from 2004 to 2023, were used to construct the FDC of the river at Halwen station for each month. The flows were arranged in descending order and ranked accordingly to compute the probability of exceedance. The low flow was fixed at the 90-percentile flow (Q90) as suggested in various studies that estimate the water available for dry season irrigation (Worqlul et al. 2015; Yimam et al. 2021). From the Q90, 20% of the flow is left for environmental flow requirements and downstream needs and the remaining 80% is assumed to be available for irrigation. Similarly, the annual recharge was considered as potential for irrigation after deducting groundwater flow to rivers (Yimam et al. 2023) and a certain percentage (30%) for other consumptive use withdrawals (Siebert et al. 2010). There are two irrigation seasons in the districts. The first irrigation season is from August to December and the second is from January to July. The major crops in the first season are maize, sesame, and beans. The major crops in the second season are onion, sesame, and watermelon. Considering two major crops from each season, the crop water requirements were estimated using the FAO CROPWAT computer program. Parameters required in CROPWAT, such as the number of days for different stages of crop development, crop coefficient (Kc) values, rooting depth, depletion fraction, and yield response fraction, were taken from FAO Irrigation and Drainage Paper 56 (Allen et al. 1998). The potential irrigated area was calculated considering the local irrigation practice — basin irrigation — with the assumption of 50% irrigation efficiency and irrigation water application time of 8 hours. This was computed as a quotient of the mean Q90 flow during the irrigation seasons and irrigated duty (l/s/ha) obtained from the CROPWAT estimates for the selected crops. 14 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | October 2024 4. Results and Discussion 4.1. Model Parameter Sensitivity Analysis The sensitivity analysis result for the Halwen sub-basin (Table 3) depicted that the t-value (absolute) ranged from 9.84 (most sensitive) to 0.09 (least sensitive), and the p-value ranged from 0 (most sensitive) to 0.97 (least sensitive). The most sensitive parameters, with their order of sensitivity, were found to be depth to impermeable layer, groundwater re-evaporation coefficient, curve number, saturated hydraulic conductivity, and soil depth. All parameters (Table 3) were used to calibrate the SWAT model for a reasonable estimate of streamflow. Overall, streamflow was found to be most sensitive to soil/aquifer (i.e., depth to impervious layer, saturated hydraulic conductivity, soil depth), land and soil management (runoff curve number), and groundwater parameters (groundwater re-evaporation coefficient). Sensitive parameters can be considered from two perspectives. Firstly, such parameters are important to improve the model simulation performance. Hence, more effort is needed to understand the spatial and temporal variability of these parameters. If monitoring is planned, priority should be given to the most sensitive parameters. The second perspective is from a management viewpoint: these parameters provide insight as to how management practices are planned and designed. For instance, runoff curve number is a factor by land use and soil hydrologic group. The sensitivity of this parameter underscores the significance of land use planning and management practices. The sensitivity of groundwater evapotranspiration parameters signifies the need to focus on planting crops that are not water intensive as the parameter is the function of depth to groundwater, root depth, and soil type. Table 3. Parameter sensitivity analysis result for Halwen sub-basin. Parameter t-stat p-value Rank DEP_IMP.hru 9.845 0.000 1 GW_REVAP.gw 4.23 0.000 2 CN2.mgt -3.659 0.000 3 SOL_K.sol -3.364 0.001 4 SOL_Z.sol 1.982 0.048 5 CH_N(2).rte -1.146 0.157 6 ALPHA_BF.gw 1.252 0.211 7 ESCO.hru -1.098 0.273 8 OV_N.hru 0.631 0.528 9 SOL_AWC.sol 0.437 0.662 10 CH_S(2).rte -0.392 0.695 11 SLSUBBSN.hru 0.369 0.712 12 GWQMN.gw 0.348 0.728 13 SURLAG.bsn -0.073 0.942 14 CH_N(1).sub 0.063 0.949 15 CH_S(1).sub -0.090 0.968 16 October 2024 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | 15 4.2. Model Calibration and Validation The SWAT model calibration and uncertainty analysis were conducted using SWAT-CUP. The fitted parameters are provided in Table 4. Figure 7 shows the observed and simulated flow at Halwen station. The model was able to reproduce the temporal dynamics of the observed flow pattern. However, the model underestimates the recession flow part of the observed streamflow. This could be the result of the poor quality of observed streamflow after rainy seasons. Despite this, the performance statistics of the model calibration and validation are “satisfactory” based on Moriasi et al. (2007). The NSE of 0.63 and R2 of 0.75 were obtained during calibration and the NSE of 0.51 and R2 of 0.68 during validation periods. The overall model simulation showed a slight underestimation of the observed flow. The mean monthly observed discharge during the calibration and validation period was 120.9 m3/s, whereas it was 95.2 m3/s for simulated flow. However, the model performance was acceptable and can be used to generate reasonable results for the sub-basin and districts. It is important to note that the quality of streamflow data is a limiting factor when conducting water balance assessments using modelling approaches. This study used old and short periods of observed flow due to a lack of long-term and recent streamflow data. We used remote sensing products on weather data to extend the flow simulation to recent years. The need to improve streamflow data measurements in this basin is recommended for better characterization of the water availability of the districts. Ethiopia is a data-scarce country in need of better streamflow data observations (Taye et al. 2023). Table 4. Parameter sensitivity analysis results for Halwen sub-basin. Parameter Fitted value Actual watershed average value DEP_IMP.hru 3689.11 0.391767 GW_REVAP.gw 0.141694 0.141694 CN2.mgt -0.305367 54.25 SOL_K.sol -0.166527 ** SOL_Z.sol 0.009279 ** Community consultation at Bokolmayo,Somali Region, Ethiopia. Photography by Wolde Mekuria Continued > 16 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | October 2024 Parameter Fitted value Actual watershed average value CH_N(2).rte 0.170570 0.170570 ALPHA_BF.gw 0.419594 0.419594 ESCO.hru 0.998256 0.998256 v_OV_N.hru 0.242557 0.242557 r_SOL_AWC.sol 0.219011 ** r_CH_S(2).rte -0.279924 0.002053 r_SLSUBBSN.hru 0.020378 * v_GWQMN.gw 1465.55 1465.55 v_SURLAG.bsn 0.604284 0.604284 v_CH_N(1).sub 0.163720 0.163720 r_CH_S(1).sub -0.345117 0.005908 Note: * and ** refer to values that vary per HRU and soil depth, respectively. Fl o w (m 3 / s) 100 300 200 500 400 600 Year Obs NSE = 0.63 R2 = 0.75 Calibration Validation NSE = 0.51 R2 = 0.68 Sim Jan-85 Feb-86 Mar-87 Apr-88 May-89 Figure 7. Comparison of monthly observed and simulated stream flow during the calibration (1985 to 1987) and validation (1988 to 1989) periods. Source: Authors’ creation. 4.3. Hydrologic Response of Dolo Ado and Bokolmayo Districts The mean annual rainfall, 2004 to 2023, of Dolo Ado and Bokolmayo districts was 302 mm. It is evidenced that evapotranspiration is the dominant hydrologic balance component in the districts (Figure 8). Evapotranspiration accounts for 76% (270 mm) while percolation accounts for 20% (60 mm). Surface runoff and sub-surface flow account for 3% and 1% of the annual rainfall in the districts, 9 mm and 6 mm, respectively. According to the Genale Dawa River Basin Master Plan, Ministry of Water Resources Ethiopia (2005), the mean annual runoff depth was below 20 mm for most of the district area, which is consistent with our findings. October 2024 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | 17 The hydrologic balance result showed that a high proportion of rainfall is lost in the form of evapotranspiration. Surface runoff and sub-surface flow are the smallest component of the overall water balance. The limited contribution of surface runoff from the districts indicates challenges in accessing and harnessing surface runoff from rainwater harvesting. The need for innovative approaches to store water when available should be considered. This can be both surface and ground storage mechanisms to increase the water supply side. The two major rivers, Genale and Dawa, flow across the boundaries of the districts. Even if surface water runoff generation is limited in the districts, the two major rivers provide reliable water sources for communities close to the rivers. The communities that are far away from the rivers have water access challenges due to inadequate infrastructure to access surface water and technology needs to withdraw groundwater from deep aquifers. In the districts, the refugee camps and towns are close to the river (Figure 6). In addition, from the water demand perspective, measures are needed to improve efficiency and reduce evapotranspiration losses, for example through water-saving irrigation techniques and land use practices that optimize water resource usage. 302 230 9 60 3 0 50 100 150 200 250 300 350 PCP ETSSF PERC Q Figure 8. Hydrologic responses of Dolo Ado and Bokolmayo districts. PCP, ET, Q, PERC, and SSF were precipitation, evapotranspiration, surface runoff, percolation, and sub-surface flow, respectively. All units are in mm. Genale River crossing the study sites, Somali Region, Ethiopia. Photography by Wolde Mekuria 4.4. Water Availability 6 TWAP Transboundary Aquifer Information sheet AF43-Dawa, version September 2015 (www.unigrac.org) 7 https://blogs.worldbank.org/en/water/digging-deep--groundwater-in-the-horn-of-africa-s-fragile-border Total surface water availability for Dolo Ado and Bokolmayo districts based on the simulated streamflow varied between 10.7 m3/s in February and 348 m3/s in May (Figure 9). This is equivalent to 26 MCM in February and 843 MCM in May. The available flow for irrigation in seasons 1 and 2 is 28.3 m3/s and 31.0 m3/s respectively. The average irrigation duty for the two crops (maize and sesame) in the first season is 0.8 l/s/ha and for the second season with onion and sesame is 0.98 l/s/ ha. Considering irrigation efficiency and 8hr irrigation time, the duty will be 4.8 l/s/ha and 5.9 l/s/ha for seasons 1 and 2, respectively. The potential irrigated area is estimated to be around 5,900 ha and 5,300 ha for seasons 1 and 2, respectively. Fl o w (m 3 / s) 100 50 150 250 350 0 200 300 400 Date Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Streamflow Q90 flow Figure 9. Water availability; surface water availability from streamflow and irrigation water availability for Dolo Ado and Bokolmayo districts. Source: Authors’ creation. The mean annual recharge for the districts was estimated to be 58 mm. It varies between 0.2 mm in September and 16.6 mm in December, equivalent to 1.6 MCM in September and 135 MCM in December considering 50% of the recharge for irrigation (Figure 10). The result indicated that there is more surface water potential for irrigation in the districts than groundwater. The research team developed a groundwater level map based on boreholes and hand-dug wells data as shown in Figure 11. The total borehole depths range from 40 m to 319 m, and the depth of hand-dug wells ranges from 1.6 m to 24 m below the surface. The depth to groundwater in the districts ranges from 2 m to 72 m below the ground surface. Comparing the two districts, depth to groundwater in the Dolo Ado district is relatively shallow. Dolo Ado district is located toward the outlet of Genale Dawa River Basin with a gentle slope, mostly less than 2%. Groundwater potential is relatively good along the rivers. Given the spatial distribution of groundwater (Figure 11), communities that are far from the river can use this resource as their primary water source. Aquifer yields are low at shallow depth ranging from 0.2 L/s to 2.3 L/s. The Dawa transboundary aquifer shared by Ethiopia, Kenya, and Somalia has an estimated area of 31,000 km2 and only a small portion of the available resource has been used6. The aquifer is under investigation through the Horn of Africa Groundwater for Resilience Project to increase water access for the fragile community7 such as the Dolo Ado and Bokolmayo districts. The aquifer underneath the districts could potentially play a vital role in the future. There is information that the depth to groundwater in the Ethiopian side of the Dawa transboundary aquifer is deep (around 100 m) with the problem of ensuring salinity as per drinking water standards, while in the Kenya side the depth is reported to be less than 10 m. October 2024 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | 19 R ec h ar g e (m m ) 4 2 6 10 14 16 0 8 12 18 Date Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Figure 10. The long-term (2004–2023) mean monthly recharge. Figure 11. Locations of groundwater wells, depth to groundwater spatial map during wet season and the Dawa transboundary aquifer. Source: Authors’ creation. 20 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | October 2024 4.5. Water Accessibility The Dolo Ado and Bokolmayo districts and the region in general face significant challenges, primarily due to water scarcity in quantity and quality (Olana and Abegaz 2023; Yussuf and Mohamed 2022). One of the most pressing issues is the limited access to water resources, exacerbated by erratic rainfall patterns and prolonged droughts (Demelash 2017). Several water accessibility challenges were reported in the literature and during the stakeholder consultation. These includes a lack of water storage (Osman 2015), technologies to access water (GebreMichael and Kifle 2009), financial resources to buy technologies (Tekola 2016), and groundwater quality issues such as salinity in shallow wells and boreholes (Mekuria et al. 2023). In addition, the high fuel cost of pumps, lack of spare parts for pumps, and canal damage due to siltation were issues that further aggravated water accessibility challenges in the area (Tekola 2016). However, communities living close to the river (refugee camps and some of the host communities) are reported to have better access to water. Studies such as Demelash (2017), Handzel (2018), and Mekuria et al. (2023), and revealed that lack of proper water storage facilities and distribution networks hampers efforts to effectively manage available water resources and mitigate the impacts of water scarcity on local communities. In addition, the seasonality of ponds which run out of water quickly and groundwater salinity issues were raised during stakeholder consultation (Mekuria et al. 2023). This impacts agricultural productivity, as farmers struggle to secure sufficient water for irrigation, livestock watering, and domestic use (Shigute et al. 2023). Furthermore, inadequate access to clean water, sanitation facilities, and hygiene aggravates the high risk of waterborne disease in local communities (Rickart et al. 2020). Shigute et al. (2023) explained that the outbreak of human and livestock diseases in the area was associated with inadequate access and improper usage of water. Efforts to address water accessibility/security challenges must account for the need for more investment in infrastructure such as water storage (Levine et al. 2021; Osman 2015) and water harvesting structures (Olana and Abegaz 2023; Shigute et al. 2023). Similarly, investing in water lifting technologies or pumps, for instance, would provide access to water from groundwater and rivers during dry spells (Mekuria et al. 2023). These are essential steps in enhancing the resilience of local communities against future drought. For the sustainability of this approach, various factors have to be considered such as environment, energy requirement, and resource management. In addition, community engagement and capacity-building aimed at promoting water conservation practices can contribute to sustainable water access (Negewo and Sarma 2021). 4.6. Technology Needs In the drought-prone regions of Dolo Ado and Bokolmayo districts, interventions with context-specific technologies are crucial for ameliorating water access and/or availability and building resilience in the face of recurring drought. This can be done in two ways: improving access to water through technologies and infrastructure and improving water availability using efficient technologies and practices. For instance, the use of water-lifting pumps would sustain water supply to the farming community and their livestock (Tekola 2016). To reduce the fuel cost of pumps, expansion of the existing solar pump use is paramount for ensuring ease of water access. Similarly, investing in community-level water storage mechanisms (Levine et al. 2021) and groundwater wells would improve water availability and access for the community. Diversification of water supply is an approach that can be used to increase water availability. Diversification entails the use of combinations of water sources as opposed to a single water source for different uses. As the siltation of canals limits water accessibility for irrigation, the continuous cleaning of the canals through dredging using local techniques will increase uninterrupted water accessibility. Various technologies and practices can be employed to save water and consequently improve water availability. These include, for instance, the adoption of climate-smart agriculture that uses precision agriculture techniques such as drip and sprinkler irrigation (Mekuria et al. 2023) to maximize crop yield while minimizing water usage. In this context, studies in the region suggested the use of efficient water application technologies (Shigute et al. 2023; Demelash 2017). To accurately estimate the efficient water amount that is applied to crop, technologies such as wetting front detector tools (Magombeyi et al. 2021) and Chameleon soil water sensors (Stirzaker et al. 2017) can be used. In addition, the use of drought-tolerant crop varieties (GebreMichael and Kifle 2009) and agroforestry systems (Worku et al. 2014) can enhance water-saving and the resilience of farming communities. Similarly, the implementation of conservation improves water-savings and crop productivity (PfR and UN Environment 2020). Furthermore, access to impact-based weather forecasting tools and mobile applications or calls that provide timely agricultural advisories would also empower farmers to make proactive decisions in effective water management (Levine et al. 2021). Harnessing the potential of water storage, water- lifting, and water application technologies, forecasting tools, and water-saving practices would help the local community to adapt to the challenges posed by drought in the districts. October 2024 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | 21 5. Conclusion and Recommendations This study provides insights into the status of water availability, accessibility, and technology needs in Dolo Ado and Bokolmayo districts. The following points summarize the main findings: { From the hydrological modeling it is evident that surface runoff is the lowest water balance component for the districts. This indicates that the major water sources for the districts are mainly derived from the rivers that are passing adjacent to the districts. { Communities living close to the rivers have more access to water while there is a challenge of high cost to lift water from the rivers to domestic and irrigation use. { Groundwater accessibility is limited due to water quality issues, e.g., salinity. { Based on the available water, the potential irrigated area is estimated to be around 5,900 ha and 5,300 ha for irrigation season 1 and 2, respectively. { The results show that there is more surface water potential for irrigation in the districts than groundwater. { There is awareness and use of solar pumps for irrigation water accessibility which needs to be expanded to alleviate the burden of high fuel cost of diesel pumps. The findings reveal the need for a multiphased approach that integrates short-term and long-term strategies to address water scarcity challenges. This comprises immediate interventions on infrastructure improvement for water access and promotion of water use efficiency; efforts in long-term approaches of integrated water management should also be undertaken. This study recommends the following actions: { The need to shift from basin irrigation to water-saving technologies such as drip and sprinkler irrigation systems. { Diversification of water supply sources such as conjunctive use of groundwater and surface water, and use of different water sources. { Investing in the rehabilitation and maintenance of existing water infrastructure, such as wells, boreholes, and irrigation canals is essential to enhance water availability and distribution. { The promotion of efficiency through water-saving technologies such as efficient water application techniques through wetting front detector tools and Chameleon soil water sensors. { Emphasis needs to be given to maximizing productivity while conserving water through the adoption of innovative cropping patterns and agronomic practices. This includes choosing crop varieties that are drought tolerant and those that are not water intensive. { Watershed management practices should be promoted to increase the recharge of water to groundwater. This includes reforestation, soil conservation, and proper land- use planning and management. { Integrated water storage mechanisms to bridge water availability during dry seasons and droughts should be promoted for these districts. Addressing water availability and accessibility challenges in the Dolo Ado and Bokolmayo districts requires synergies and collaborative efforts among government agencies, humanitarian organizations, local communities, and other stakeholders. A diverse range of demographics in the districts must be considered in addressing water-related challenges. This includes host communities comprised of local residents, refugees, and IDPs. To address the differing risks and needs, follow-up work should prioritize inclusivity and tailored approaches. For instance, engaging representatives from host communities, refugees, and IDPs in decision-making processes related to water resources management is a key step. Gender considerations are also critical, as women within these groups often bear unique responsibilities and vulnerabilities regarding water access. In addition, capacity-building initiatives should empower all community members to actively participate in water resources management. Long-term sustainability efforts should extend beyond immediate humanitarian assistance, for instance, and focus on infrastructure development and natural resource management that benefit all demographics. These integrated efforts are essential to creating a sustainable and resilient future, ensuring equitable access to water resources while conserving the ecosystem. 22 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | October 2024 References Abate, B.Z.; Assefa, T.T.; Tigabu, T.B.; Abebe, W.B.; He, L. 2023. Hydrological Modeling of the Kobo-Golina River in the Data- Scarce Upper Danakil Basin, Ethiopia. Sustainability 15(4): 3337. https://doi.org/10.3390/su15043337 Allen, R.G.; Pereira, L.S.; Raes, D.; Smith, M. 1998. Crop evapotranspiration-Guidelines for computing crop water requirements. FAO Irrigation and Drainage Paper No. 56. Food and Agriculture Organization of the United Nations (FAO) 300(9): D05109. Rome, Italy: FAO. Available at https://www.researchgate.net/publication/235704197_Crop_evapotranspiration-Guidelines_ for_computing_crop_water_requirements-FAO_Irrigation_and_drainage_paper_56 (accessed on September 28, 2024). Arnold, J.G.; Fohrer, N. 2005. SWAT2000: current capabilities and research opportunities in applied watershed modelling. Hydrological Processes 19(3): 563–572. https://doi.org/10.1002/hyp.5611 Arnold, J.G.; Moriasi, D.N.; Gassman, P.W.; Abbaspour, K.C.; White, M.J; Srinivasan, R.; Santhi, C.; Harmel, R.; Van Griensven, A.; Van Liew, M.W.; Kannan, N.; Jha, M.K. 2012. SWAT: Model use, calibration, and validation. Transactions of the ASABE 55(4): 1491–1508. https://doi.org/10.13031/2013.42256 Arnold, J.G.; Srinivasan, R.; Muttiah, R.S.; Williams, J.R. 1998. Large area hydrologic modeling and assessment part I: model development 1. JAWRA Journal of the American Water Resources Association 34(1), 73–89. https://doi. org/10.1111/j.1752-1688.1998.tb05961.x Betts, A.; Bradenbrink, R.; Greenland, J.; Omata, N.; Sterck, O. 2019. Refugee economies in Dollo Ado: development opportunities in a border region of Ethiopia. Oxford: Refugee Studies Centre, Oxford Department of International Development, University of Oxford. Available at https://ora.ox.ac.uk/objects/uuid:ca7b9d74-03be-4c64-a1aa-1bdbf1eb38b4 (accessed on April 1, 2024). Cepeda Arias, E.; Cañon Barriga, J. 2022. Performance of high-resolution precipitation datasets CHIRPS and TerraClimate in a Colombian high Andean Basin. Geocarto International 37(27): 17382–17402. https://doi.org/10.1080/10106049.2022.2129816 Condom, T.; Martínez, R.; Pabón, J.D.; Costa, F.; Pineda, L.; Nieto, J.J.; López, F.; Villacis, M. 2020. Climatological and hydrological observations for the South American Andes: in situ stations, satellite, and reanalysis data sets. Frontiers in Earth Science 8. https://doi.org/10.3389/feart.2020.00092 de Trincheria, J.; Oduor, A.; Ngigi, S.; Oremo, F.O.; Ngondi, J.; van Steenbergen, F.; Nyawasha, R.W.; Dawit, D.; Mussera P.V.; Woldearegay, K.; Koelman, E.M.; Malesu, M.; Famba, S.; Simane, B.; Wuta, M.; Oguge, N.O.; Leal Filho, W. 2017. Advanced Training Materials on Rainwater Harvesting Irrigation Management in Arid and Semi-arid Areas of Sub-Saharan Africa: Technical Capacity Building on the Use of Rainwater for Off-season Small-scale Irrigation in Ethiopia, Kenya, Mozambique and Zimbabwe. Hamburg, Germany: Hamburg University of Applied Sciences. Available at https://tapipedia.org/content/ advanced-training-materials-rainwater-harvesting-irrigation-management-arid-and-semi-arid (accessed on April 1, 2024). Demelash, A. 2017. Assessment of Land Suitability for Surface Irrigation Development in Weiyb Sub Basin, Genale-Dawa River Basin, Ethiopia. Haramaya, Ethiopia: Haramaya University. Destrijcker, L.; Yishak, M.; Thomson, M.; Traore, A.; Xu, Y.A.; Kurnoth, H. 2023. Climate, Peace and Security Study: Somali Region, Ethiopia. Berlin, Germany: Adelphi Research Gemeinnützige GmbH. Available at https://weatheringrisk.org/sites/ default/files/document/Climate_Peace_Security_Study_Somali_Region_Ethiopia.pdf (accessed on April 1, 2024). Dile, Y.T.; Srinivasan, R. 2014. Evaluation of CFSR climate data for hydrologic prediction in data‐scarce watersheds: an application in the Blue Nile River Basin. JAWRA Journal of the American Water Resources Association 50(5): 1226–1241. https://doi.org/10.1111/jawr.12182 Dinku, T.; Funk, C.; Peterson, P.; Maidment, R.; Tadesse, T.; Gadain, H.; Ceccato, P. 2018. Validation of the CHIRPS satellite rainfall estimates over eastern Africa. Quarterly Journal of the Royal Meteorological Society 144(S1): 292–312. https://doi. org/10.1002/qj.3244 October 2024 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | 23 https://doi.org/10.3390/su15043337 https://www.researchgate.net/publication/235704197_Crop_evapotranspiration-Guidelines_for_computing_crop_water_requirements-FAO_Irrigation_and_drainage_paper_56 https://www.researchgate.net/publication/235704197_Crop_evapotranspiration-Guidelines_for_computing_crop_water_requirements-FAO_Irrigation_and_drainage_paper_56 https://doi.org/10.1002/hyp.5611 https://doi.org/10.13031/2013.42256 https://doi.org/10.1111/j.1752-1688.1998.tb05961.x https://doi.org/10.1111/j.1752-1688.1998.tb05961.x https://ora.ox.ac.uk/objects/uuid:ca7b9d74-03be-4c64-a1aa-1bdbf1eb38b4 https://doi.org/10.1080/10106049.2022.2129816 https://doi.org/10.3389/feart.2020.00092 https://tapipedia.org/content/advanced-training-materials-rainwater-harvesting-irrigation-management-arid-and-semi-arid https://tapipedia.org/content/advanced-training-materials-rainwater-harvesting-irrigation-management-arid-and-semi-arid https://weatheringrisk.org/sites/default/files/document/Climate_Peace_Security_Study_Somali_Region_Ethiopia.pdf https://weatheringrisk.org/sites/default/files/document/Climate_Peace_Security_Study_Somali_Region_Ethiopia.pdf https://doi.org/10.1111/jawr.12182 https://doi.org/10.1002/qj.3244 https://doi.org/10.1002/qj.3244 Gao, F.; Zhang, Y.; Ren, X.; Yao, Y.; Hao, Z.; Cai, W. 2018. Evaluation of CHIRPS and its application for drought monitoring over the Haihe River Basin, China. Natural Hazards 92: 155–172. https://doi.org/10.1007/s11069-018-3196-0 Gassman, P.W.; Reyes, M.R.; Green, C.H.; Arnold, J.G. 2005. SWAT peer-reviewed literature: a review. In: 3rd International SWAT Conference, Zurich, Switzerland. Vol. 13. Available at https://swat.tamu.edu/docs/swat/conferences/2005/PDF/Session_I/ Gassman.pdf (accessed on April 1, 2024). GebreMichael, Y.; Kifle, M. 2009. Local innovation in climate-change adaptation by Ethiopian pastoralists. Addis Ababa, Ethiopia. PROLINNOVA–Ethiopia and Pastoralist Forum Ethiopia (PFE). pp.1–25. Available at https://prolinnova.net/ wp-content/files/documents/thematic_pages/climate_change_pid/2009/Ethiopia%20pastoral%20climate-change%20 adaptation%20FINAL%20_2_.pdf (accessed on April 1, 2024). Giller, K.E. 2020. The food security conundrum of sub-Saharan Africa. Global Food Security 26: 100431. https://doi. org/10.1016/j.gfs.2020.100431 Gleixner, S.; Demissie, T.; Diro, G.T. 2020. Did ERA5 improve temperature and precipitation reanalysis over East Africa? Atmosphere 11(9): 996. https://doi.org/10.3390/atmos11090996 Haile, G.G.; Tang, Q.; Sun, S.; Huang, Z.; Zhang, X.; Liu, X. 2019. Droughts in East Africa: Causes, impacts and resilience. Earth- science reviews 193: 146–161. https://doi.org/10.1016/j.earscirev.2019.04.015 Handzel, T. 2018. Water, Sanitation, and Hygiene (WASH). Health in Humanitarian Emergencies: In: Principles and Practice for Public Health and Healthcare Practitioners. Cambridge, U.K.: Cambridge University Press. pp.136-160. Available at https:// www.cambridge.org/core/terms. https://doi.org/10.1017/9781107477261.012 (accessed on April 1, 2024). Ibe, G.; Amikuzuno, J. 2019. Climate change in Sub-Saharan Africa: A menace to agricultural productivity and ecological protection. Journal of Applied Sciences and Environmental Management 23(2): 329–335. https://doi.org/10.4314/jasem. v23i2.20 Jayakrishnan, R.; Srinivasan, R.; Santhi, C.; Arnold, J. 2005. Advances in the application of the SWAT model for water resources management. Hydrological Processes: An International Journal 19(3): 749–762. https://doi.org/10.1002/hyp.5624 Krampe, F.; Van De Goor, L.; Barnhoorn, A.; Smith, E.; Smith, D. 2020. Water security and governance in the Horn of Africa. SIPRI Policy Paper 54. Stockholm International Peace Research Institute. Available at https://www.diva-portal.org/smash/get/ diva2:1424710/FULLTEXT01.pdf (accessed on April 1, 2024). Krysanova, V.; White, M. 2015. Advances in water resources assessment with SWAT—an overview. Hydrological Sciences Journal 60(5): 771–783. https://doi.org/10.1080/02626667.2015.1029482 Leal Filho, W.; Taddese, H.; Balehegn, M.; Nzengya, D.; Debela, N.; Abayineh, A.; Mworozi, E.; Osei, S.; Ayal, D.Y.; Nagy, G.J. 2020. Introducing experiences from African pastoralist communities to cope with climate change risks, hazards and extremes: Fostering poverty reduction. International Journal of Disaster Risk Reduction 50: 101738. https://doi.org/10.1016/j. ijdrr.2020.101738 Levine, S.; Humphrey, A.; Weingärtner, L.; Sheikh, M. 2021. Understanding the role of anticipatory action in Somalia. SPARC Issue Brief. pp.3–8. Available at https://www.sparc-knowledge.org/sites/default/files/documents/resources/ Understanding%20the%20role%20of%20anticipatory%20action%20in%20Somalia%20Hi%20Res.pdf Magombeyi, M; Lautze, J.; Schmitter, P. 2021. Agricultural Water Solutions in the Tuli Karoo Aquifer Area. United States Agency for International Development (USAID) and the CGIAR Research Program on Water, Land and Ecosystems (WLE). Available at https://conjunctivecooperation.iwmi.org/wp-content/uploads/sites/38/2021/02/AgWaterTuliJan21.pdf (accessed on April 1, 2024). Mebrie, D.W.; Assefa, T.T.; Yimam, A.Y.; Belay, S.A. 2023. A remote sensing approach to estimate variable crop coefficient and evapotranspiration for improved water productivity in the Ethiopian highlands. Applied Water Science 13: 168. https://doi. org/10.1007/s13201-023-01968-5 24 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | October 2024 https://doi.org/10.1007/s11069-018-3196-0 https://swat.tamu.edu/docs/swat/conferences/2005/PDF/Session_I/Gassman.pdf https://swat.tamu.edu/docs/swat/conferences/2005/PDF/Session_I/Gassman.pdf https://prolinnova.net/wp-content/files/documents/thematic_pages/climate_change_pid/2009/Ethiopia%20pastoral%20climate-change%20adaptation%20FINAL%20_2_.pdf https://prolinnova.net/wp-content/files/documents/thematic_pages/climate_change_pid/2009/Ethiopia%20pastoral%20climate-change%20adaptation%20FINAL%20_2_.pdf https://prolinnova.net/wp-content/files/documents/thematic_pages/climate_change_pid/2009/Ethiopia%20pastoral%20climate-change%20adaptation%20FINAL%20_2_.pdf https://doi.org/10.1016/j.gfs.2020.100431 https://doi.org/10.1016/j.gfs.2020.100431 https://doi.org/10.3390/atmos11090996 https://doi.org/10.1016/j.earscirev.2019.04.015 https://doi.org/10.1017/9781107477261.012 https://doi.org/10.1017/9781107477261.012 https://doi.org/10.4314/jasem.v23i2.20 https://doi.org/10.4314/jasem.v23i2.20 https://doi.org/10.1002/hyp.5624 https://www.diva-portal.org/smash/get/diva2:1424710/FULLTEXT01.pdf https://www.diva-portal.org/smash/get/diva2:1424710/FULLTEXT01.pdf https://doi.org/10.1080/02626667.2015.1029482 https://doi.org/10.1016/j.ijdrr.2020.101738 https://doi.org/10.1016/j.ijdrr.2020.101738 https://www.sparc-knowledge.org/sites/default/files/documents/resources/Understanding%20the%20role%20of%20anticipatory%20action%20in%20Somalia%20Hi%20Res.pdf https://www.sparc-knowledge.org/sites/default/files/documents/resources/Understanding%20the%20role%20of%20anticipatory%20action%20in%20Somalia%20Hi%20Res.pdf https://conjunctivecooperation.iwmi.org/wp-content/uploads/sites/38/2021/02/AgWaterTuliJan21.pdf https://doi.org/10.1007/s13201-023-01968-5 https://doi.org/10.1007/s13201-023-01968-5 Mekuria, T. 2022. The effects of Flooding and Drought on Clean Water Accesibility in Ethiopia. Hydrolink 2022/1. Madrid: International Association for Hydro-Environment Engineering and Research (IAHR). pp.18–21. Available at https://hdl.handle. net/20.500.11970/109536 (accessed on April 1, 2024). Mekuria, W.; Dessalegn, M.; Yimer, G.; Tamiru, A.; Tegegne, A.D. 2023. Nature-based and other Solutions for Human Resilience. Unpublished. Mohamed, A.A. 2017. Food security situation in Ethiopia: a review study. International journal of health economics and policy 2(3): 86–96. Available at https://www.sciencepublishinggroup.com/article/10.11648/j.hep.20170203.11 Moriasi, D.N.; Arnold, J.G.; Van Liew, M.W.; Bingner, R.L.; Harmel, R.D.; Veith, T.L. 2007. Model evaluation guidelines for systematic quantification of accuracy in watershed simulations. Transactions of the ASABE 50(3): 885–900. https://doi. org/10.13031/2013.23153 MoWR (Ministry of Water Resources Ethiopia). 2005. Genale Dawa River Basin Integrated Resources Development Master Plan and Study Project. Unpublished. Nazari-Sharabian, M.; Taheriyoun, M.; Karakouzian, M. 2020. Sensitivity analysis of the DEM resolution and effective parameters of runoff yield in the SWAT model: a case study. Journal of Water Supply: Research and Technology—AQUA 69(1): 39–54. https://doi.org/10.2166/aqua.2019.044 Negewo, T.F.; Sarma, A.K. 2021. Spatial and temporal variability evaluation of sediment yield and sub-basins/hydrologic response units prioritization on Genale Basin, Ethiopia. Journal of Hydrology 603(D): 127190. https://doi.org/10.1016/j. jhydrol.2021.127190 Neitsch, S.L.; Arnold, J.G.; Kiniry, J.R.; Williams, J.R. 2011. Soil and water assessment tool theoretical documentation version 2009. Texas Water Resources Institute Technical Report No. 406. Agricultural Research Service (USDA) and Texas Agricultural Experiment Station, Texas A&M University, Temple. Available at https://oaktrust.library.tamu.edu/server/api/ core/bitstreams/14750fbe-4b68-4f36-bcee-baac526f13ee/content (accessed on April 1, 2024). Nkomo, J.C.; Nyong, A.; Kulindwa, K. 2006. The impacts of climate change in Africa. Final draft submitted to the Stern Review on the Economics of Climate Change. pp.1–51. Available at https://www.researchgate.net/publication/253698396_The_ Impacts_of_Climate_Change_in_Africa (accessed on September 28, 2024). Olana, A.B.; Abegaz, F. 2023. Impacts Of Climate Change On Hydro-Meteorological Drought On Dawa Watershed, Genale Dawa River Basin, Ethiopia. haramaya, Ethiopia: Haramaya University. Available at http://ir.haramaya.edu.et/hru/ handle/123456789/6994 (accessed on April 1, 2024). Osman, A.A. 2015. Livelihood Diversification as Coping Strategy for Climate Change Affected Pastoralist Communities in Liban Zone of Ethiopian Somali Regional State (ESRS): The Case of Filtu and Dollo-ado Districts. Thesis. Addis Ababa, Ethiopia: Addis Ababa University, College Of Development Studies (CDS), Center for Regional and Local Development Studies (RLDS). Available at https://www.academia.edu/78011632/ (accessed on April 1, 2024). PfR (Partners for Resilience) and UN Environment. 2020. Regional Baseline of Dolo Ado Woreda, Somali Region, Ethiopia. An assessment towards building resilience through Ecosystem-based Disaster Risk Reduction. Gouda, The Netherlands. Available at https://acaciadata.com/doc/2020%20Dolo%20Ado%20Woreda%20Regional%20Baseline%20Mapbook.pdf (accessed on April 1, 2024). Rickart, A.J., Rodgers, W.; Mizen, K.; Merrick, G.; Wilson, P.; Nishikawa, H.; Dunaway, D.J. 2020. Facing Africa: describing noma in Ethiopia. The American journal of tropical medicine and hygiene 103(2): 613–618. https://doi.org/10.4269/ajtmh.20-0019 Serdeczny, O.; Adams, S.; Baarsch, F.; Coumou, D.; Robinson, A.; Hare, W.; Schaeffer, M.; Perrette, M.; Reinhardt, J. 2017. Climate change impacts in Sub-Saharan Africa: from physical changes to their social repercussions. Regional Environmental Change 17: 1585–1600. https://doi.org/10.1007/s10113-015-0910-2 Shankar, S. 2018. Impacts of climate change on agriculture and food security. In: Singh, R.S.; Mondal, S. (eds.) Biotechnology for Sustainable Agriculture Emerging Approaches and Strategies. Woodhead Publishing. pp.207–234. https://doi.org/10.1016/ B978-0-12-812160-3.00007-6 October 2024 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | 25 https://hdl.handle.net/20.500.11970/109536 https://hdl.handle.net/20.500.11970/109536 https://www.sciencepublishinggroup.com/article/10.11648/j.hep.20170203.11 https://doi.org/10.13031/2013.23153 https://doi.org/10.13031/2013.23153 https://doi.org/10.2166/aqua.2019.044 https://doi.org/10.1016/j.jhydrol.2021.127190 https://doi.org/10.1016/j.jhydrol.2021.127190 https://oaktrust.library.tamu.edu/server/api/core/bitstreams/14750fbe-4b68-4f36-bcee-baac526f13ee/content https://oaktrust.library.tamu.edu/server/api/core/bitstreams/14750fbe-4b68-4f36-bcee-baac526f13ee/content https://www.researchgate.net/publication/253698396_The_Impacts_of_Climate_Change_in_Africa https://www.researchgate.net/publication/253698396_The_Impacts_of_Climate_Change_in_Africa http://ir.haramaya.edu.et/hru/handle/123456789/6994 http://ir.haramaya.edu.et/hru/handle/123456789/6994 https://www.academia.edu/78011632/ https://acaciadata.com/doc/2020%20Dolo%20Ado%20Woreda%20Regional%20Baseline%20Mapbook.pdf https://doi.org/10.4269/ajtmh.20-0019 https://doi.org/10.1007/s10113-015-0910-2 https://doi.org/10.1016/B978-0-12-812160-3.00007-6 https://doi.org/10.1016/B978-0-12-812160-3.00007-6 Shigute, M.; Alamirew, T.; Abebe, A.; Ndehedehe, C.E.; Kassahun, H.T. 2022. Understanding Hydrological Processes under Land Use Land Cover Change in the Upper Genale River Basin, Ethiopia. Water 14(23): 3881. https://doi.org/10.3390/w14233881 Shigute, M.; Alamirew, T.; Abebe, A.; Ndehedehe, C.E.; Kassahun, H.T. 2023. Analysis of rainfall and temperature variability for agricultural water management in the upper Genale river basin, Ethiopia. Scientific African 20: e01635. https://doi. org/10.1016/j.sciaf.2023.e01635 Siebert, S.; Burke, J.; Faures, J.-M.; Frenken, K.; Hoogeveen, J.; Döll, P.; Portmann, F.T. 2010. Groundwater use for irrigation–a global inventory. Hydrology and earth system sciences 14: 1863–1880. https://doi.org/10.5194/hess-14-1863-2010 Stirzaker, R.; Mbakwe, I.; Mziray, N.R. 2017. A soil water and solute learning system for small-scale irrigators in Africa. International Journal of Water Resources Development 33(5): 788–803. https://doi.org/10.1080/07900627.2017.1320981 Sultan, B.; Gaetani, M. 2016. Agriculture in West Africa in the twenty-first century: climate change and impacts scenarios, and potential for adaptation. Frontiers in Plant Science 7: 211434. https://doi.org/10.3389/fpls.2016.01262 Taye, M.T.; Zimale, F.A.; Woldesenbet, T.A.; Kebede, M.G.; Amare, S.D.; Tegegne, G.; Mekonnen, K.; Haile, A.T. 2023. Priority research topics to improve streamflow data availability in data-scarce countries: the case for Ethiopia. Hydrology 10(12): 220. https://doi.org/10.3390/hydrology10120220 Tekola, S. 2016. Comparison of irrigation based agro-pastoralists with pastoralists livelihood in case of Dolo Ado and Dolo Bay Woredas, Somali Region, Ethiopia. Thesis. Addis Ababa, Ethiopia: St. Mary’s University. Available at http://repository.smuc. edu.et/bitstream/123456789/6751/1/Sisay%27s%20Final%20thesis%202016.pdf (accessed on April 1, 2024). Thejll, P.; Gleisner, H. 2015. Reanalysis data. In: Lilensten, J.; Dudok de Wit, T.; Matthes, K. (eds.) Earth’s climate response to a changing Sun. EAS Publication Series. Available at https://www.researchgate.net/publication/311107863_Reanalysis_data (accessed on April 1, 2024). Ugas, M.; Eggenberger, W. 1999. Drought and floods stress livelihoods and food security in the Ethiopian Somali region. Addis Ababa, Ethiopia: United Nations Development Programme Emergencies Unit of Ethiopia (UNDP-EUE). Available at https:// reliefweb.int/report/ethiopia/drought-and-floods-stress-livelihoods-and-food-security-ethiopian-somali-region (accessed on September 28, 2024). UNHCR (United Nations High Commissioner for Refugees). n. d. Climate change and disaster displacement. Available at https:// www.unhcr.org/africa/what-we-do/how-we-work/environment-disasters-and-climate-change/climate-change-and-disaster (accessed on April 1, 2024). Uniyal, B.; Dietrich, J.; Vu, N.Q.; Jha, M.K.; Arumí, J.L. 2019. Simulation of regional irrigation requirement with SWAT in different agro-climatic zones driven by observed climate and two reanalysis datasets. Science of the total environment 649: 846–865. https://doi.org/10.1016/j.scitotenv.2018.08.248 Walker, R.J. 2016. Population growth and its implications for global security. American Journal of Economics and Sociology 75(4): 980–1004. https://doi.org/10.1111/ajes.12161 Worku, A.; Pretzsch, J.; Kassa, H.; Auch, E. 2014. The significance of dry forest income for livelihood resilience: The case of the pastoralists and agro-pastoralists in the drylands of southeastern Ethiopia. Forest Policy and Economics 41: 51–59. https:// doi.org/10.1016/j.forpol.2014.01.001 Worqlul, A.W.; Ayana, E.K.; Yen, H.; Jeong, J.; MacAlister, C.; Taylor, R.; Gerik, T.J.; Steenhuis, T.S. 2018. Evaluating hydrologic responses to soil characteristics using SWAT model in a paired-watersheds in the Upper Blue Nile Basin. Catena 163: 332–341. https://doi.org/10.1016/j.catena.2017.12.040 Worqlul, A.W.; Collick, A.S.; Rossiter, D.G.; Langan, S.; Steenhuis, T.S. 2015. Assessment of surface water irrigation potential in the Ethiopian highlands: The Lake Tana Basin. Catena 129: 76–85. https://doi.org/10.1016/j.catena.2015.02.020 Yimam, A.Y.; Assefa, T.T.; Sishu, F.K.; Tilahun, S.A.; Reyes, M.R.; Prasad, P. 2021. Estimating surface and groundwater irrigation potential under different conservation agricultural practices and irrigation systems in the Ethiopian highlands. Water 13(12): 1645. https://doi.org/10.3390/w13121645 26 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | October 2024 https://doi.org/10.3390/w14233881 https://doi.org/10.1016/j.sciaf.2023.e01635 https://doi.org/10.1016/j.sciaf.2023.e01635 https://doi.org/10.5194/hess-14-1863-2010 https://doi.org/10.1080/07900627.2017.1320981 https://doi.org/10.3389/fpls.2016.01262 https://doi.org/10.3390/hydrology10120220 http://repository.smuc.edu.et/bitstream/123456789/6751/1/Sisay%27s%20Final%20thesis%202016.pdf http://repository.smuc.edu.et/bitstream/123456789/6751/1/Sisay%27s%20Final%20thesis%202016.pdf https://www.researchgate.net/publication/311107863_Reanalysis_data https://reliefweb.int/report/ethiopia/drought-and-floods-stress-livelihoods-and-food-security-ethiopian-somali-region https://reliefweb.int/report/ethiopia/drought-and-floods-stress-livelihoods-and-food-security-ethiopian-somali-region https://www.unhcr.org/africa/what-we-do/how-we-work/environment-disasters-and-climate-change/climate-change-and-disaster https://www.unhcr.org/africa/what-we-do/how-we-work/environment-disasters-and-climate-change/climate-change-and-disaster https://doi.org/10.1016/j.scitotenv.2018.08.248 https://doi.org/10.1111/ajes.12161 https://doi.org/10.1016/j.forpol.2014.01.001 https://doi.org/10.1016/j.forpol.2014.01.001 https://doi.org/10.1016/j.catena.2017.12.040 https://doi.org/10.1016/j.catena.2015.02.020 https://doi.org/10.3390/w13121645 Yimam, A.Y.; Sishu, F.K.; Assefa, T.T.; Steenhuis, T.S.; Reyes, M.R.; Srinivasan, R.; Tilahun, S.A. 2023. Modifying the water table fluctuation method for calculating recharge in sloping aquifers. Journal of Hydrology: Regional Studies 46: 101325. https://doi.org/10.1016/j.ejrh.2023.101325 Yussuf, B.A.; Mohamed, A.A. 2022. Factors Influencing Household Livelihood Diversification: The Case of Kebri Dahar District, Korahey Zone of Somali Region, Ethiopia. Advances in Agriculture 2022. https://doi.org/10.1155/2022/7868248 October 2024 | Status Report on Water Resources Availability, Accessibility and Technology Needs for Addressing Water Security Challenges | 27 https://doi.org/10.1016/j.ejrh.2023.101325 https://doi.org/10.1155/2022/7868248 Meron Teferi Taye, Researcher, International Water Management Institute (IWMI), Addis Ababa, Ethiopia (meron.taye@cgiar.org) CGIAR is a global research partnership for a food-secure future. CGIAR science is dedicated to transforming food, land, and water systems in a climate crisis. Its research is carried out by 13 CGIAR Centers/Alliances in close collaboration with hundreds of partners, including national and regional research institutes, civil society organizations, academia, development organizations and the private sector. www.cgiar.org We would like to thank all funders who support this research through their contributions to the CGIAR Trust Fund: www.cgiar.org/funders. To learn more about this Initiative, please visit this webpage. To learn more about this and other Initiatives in the CGIAR Research Portfolio, please visit www.cgiar. org/cgiar-portfolio © 2024 International Water Management Institute (IWMI). Some rights reserved. This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 International Licence (CC by 4.0). | | | mailto:meron.taye@cgiar.org https://www.cgiar.org/initiative/fragility-conflict-and-migration/ https://www.youtube.com/channel/UCYuSEwWKAsoNwg6MJEI-qeA _GoBack _GoBack _GoBack List of Figures List of Tables Summary 1. Introduction 2. Study Area Description 3. Materials and Methods 3.1. The Framework of the Study 3.2. Description of the Hydrologic Model 3.3. Data and Sources 3.4. Hydrologic Model Setup 3.5. Model Performance Evaluation Criteria 3.6. Assessing Water Availability in the Dolo Ado and Bokolmayo Districts 4. Results and Discussion 4.1. Model Parameter Sensitivity Analysis 4.2. Model Calibration and Validation 4.3. Hydrologic Response of Dolo Ado and Bokolmayo Districts 4.4. Water Availability 4.5. Water Accessibility 4.6. Technology Needs 5. Conclusion and Recommendations References Abbreviations and Acronyms Figure 1. Location of Dolo Ado and Bokolmayo districts within the Genale Dawa River Basin. Figure 2. Spatial maps of the Dolo Ado and Bokolmayo districts in the Somali Regional State of Ethiopia: Land use (A), slope classes (B), (C) soil texture, and (D) mean annual rainfall, from 1981 to 2023. Figure 3. Mean monthly rainfall (A), and annual rainfall (B) for the Dolo Ado and Bokolmayo districts based on The Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS), 1981–2023. Figure 4. Deviation of annual rainfall from the long-term mean of the baseline period of 1981–2022 based on CHIRPS rainfall data. Figure 5. Framework to assess the status of water resource availability, accessibility, and technology needs in the Dolo Ado and Bokolmayo districts. Figure 6. Sub-watersheds of the Halwen sub-basin and districts in the Genale River Basin. Figure 7. Comparison of monthly observed and simulated stream flow during the calibration (1985 to 1987) and validation (1988 to 1989) periods. Figure 8. Hydrologic responses of Dolo Ado and Bokolmayo districts. PCP, ET, Q, PERC, and SSF were precipitation, evapotranspiration, surface runoff, percolation, and sub-surface flow, respectively. All units are in mm. Figure 9. Water availability; surface water availability from streamflow and irrigation water availability for Dolo Ado and Bokolmayo districts. Figure 10. The long-term (2004–2023) mean monthly recharge. Figure 11. Locations of groundwater wells, depth to groundwater spatial map during wet season and the Dawa transboundary aquifer. Table 1. Data types and their sources used for water availability assessment. Table 2. Calibration parameters for the SWAT model, their descriptions, and parameter space used in SWAT-CUP automated calibration and sensitivity analysis. Table 3. Parameter sensitivity analysis result for Halwen sub-basin. Table 4. Parameter sensitivity analysis results for Halwen sub-basin.