Nafn Amdar

Jordan’s Amman-Zarqa (AZ) basin faces increasing water scarcity due to increasing demands and persistent groundwater over-abstractions for irrigation. To address this issue, water conservation has been set as a national strategy, and several initiatives aiming to conserve water in irrigated agriculture have been implemented in the basin’s highlands. This study evaluates the impact of water conservation technologies (WCTs) on irrigation water savings in the AZ basin highlands. Monthly data on irrigation application were collected from 22 farms over three crop seasons (2019–2022) for four dominant orchards. Farm-scale water savings were calculated and projected to the basin scale under two scenarios: a sustainability scenario aligning groundwater abstraction with irrigation needs under WCTs and an economic scenario expanding irrigated areas using the saved water. Results show that irrigation efficiency before the influence of WCTs was below 55%, with farmers applying an average of 1277 mm/year. After implementing WCTs and farmers fine-tuning their irrigation practices, irrigation application decreased to an average of 795 mm/year, resulting in 38% water savings. Projecting these savings basin-wide, WCTs could conserve 44 Mm³/year of water under the sustainability scenario. The results provide a solid basis for informing water conservation targets in this region. However, successful water conservation using WCTs depends on farmer-led testing to ensure reduced irrigation does not compromise crop yields. Pilot programs supported by trusted technical advice through farmer field schools and appropriate incentives can achieve sustainable water conservation in this region. Concurrently, monitoring is required to regulate irrigation expansion as it could undermine water savings.

The interplay between water and agriculture is central to transboundary regions' socio-economic stability and food security, especially under the intensifying impacts of climate change. This study focuses on the water-food-energy-environment (WEFE) nexus between Syria and Jordan in the transboundary Yarmouk River Basin, highlighting the challenges, opportunities, and cooperative strategies required to address a warming climate. Water resources in the Yarmouk River Rasin are critical to both countries as they contribute massively to agricultural production. However, climate variability, political instability, and unsustainable resource management have exacerbated water scarcity, threatening agricultural resilience and regional stability.This study utilizes the Excel-based IGain4Gains nexus model alongside data on near-future (2025-2050) water resources, usage, and consumption to analyze WEFE synergies and trade-offs in the Yarmouk Basin. Three scenarios for river basin management are explored: business as usual, climate-intensified competition (focused on improving irrigation efficiency and expanding irrigated areas), and climate-resilient cooperation (emphasizing enhanced irrigation efficiency, maintaining current irrigated areas, and increasing transboundary water flows to Jordan). The scenario outputs were validated through stakeholder consultations, providing insights into sustainable transboundary cooperation pathways based on equitable nexus benefits and trade-offs between upstream and downstream users.The findings highlight that climate-resilient cooperation is the most effective approach to mitigating risks and promoting stability. Key recommendations include implementing water-saving technologies like precision irrigation and wastewater reuse, alongside strengthening institutional frameworks for joint water governance. Advancing adaptation efforts requires regional and international collaboration through targeted funding, capacity building, and knowledge exchange, ensuring policies are aligned with climate-resilient priorities for sustainable resource management.

This paper introduces and applies iGain4Gains, an Excel-based model, to reveal how changes to water conservation and allocation, and irrigation technology, can produce four nexus gains. These gains are; reduced aggregate water consumption, sustained crop production, lower carbon emissions, and enhanced water availability for nature. We developed the model with limited data and hypothetical future scenarios from the Amman–Zarqa basin in Jordan. Given its significant irrigation and urban water demands and difficult decisions regarding future water allocation and nexus choices, this basin is a highly appropriate case study. The paper’s primary aim is to demonstrate the iGains4Gains nexus model rather than to build an accurate hydrological model of the basin’s water resources. The model addresses two critical questions regarding increased irrigation efficiency. First, can irrigation efficiency and other factors, such as irrigated area, be applied to achieve real water savings while maintaining crop production, ensuring greenhouse gas emission reductions, and ‘freeing’ water for nature? Second, with the insight that water conservation is a distributive/allocative act, we ask who between four paracommoners (the proprietor irrigation system, neighbouring irrigation systems, society, and nature) benefits hydrologically from changes in irrigation efficiency? Recognising nexus gains are not always linear, positive and predictable, the model reveals that achieving all four gains simultaneously is difficult, likely leading to trade-offs such as water consumption rebounds or increased carbon emissions. Demonstrated by its use at a workshop in Jordan in February 2024, iGains4Gains can be used by students, scientists and decision-makers, to explore and understand nexus trade-offs connected to changes in irrigation management. The paper concludes with recommendations for governing water and irrigated agriculture in basins where large volumes of water are withdrawn and depleted by irrigation.

Water resources assessments are essential for effective planning in water-scarce regions such as Jordan. Such assessments require sufficient data in space and time. The WaPOR-based Water Accounting Plus (WA +) framework is relevant as it integrates remote sensing data and the Pixel-Based Soil Water Balance model to simulate a basin’s water balance. However, since it relies on remote sensing, this framework only tracks water consumption in irrigated agriculture and does not consider non-irrigation water use and its return flow. This paper modifies the WaPOR-based WA + framework to include non-irrigation manmade consumption and its return flows. The modified framework provides a more comprehensive water budget for the Amman-Zarqa (AZ) basin, presented in a modified WA + resource base sheet for 2018 through 2021. The results show that water availability in the AZ basin is highly responsive to precipitation changes. Average precipitation was approximately 926 Mm³/year between 2018 and 2020, corresponding to an average available water of 485 Mm³/year. However, a reduction in average precipitation by 28% in 2021 corresponded to a reduction in available water to 243 Mm³/year. Nevertheless, substantial groundwater outflows to neighbouring basins may indicate that available water is being overestimated. Manmade consumption increased by 18% from 2018 to 2021, and the total demand exceeded the available supply by 150%. This underscores the pressing need to investigate supply augmentation and conservation methods. Future studies could focus on improving the representation of groundwater dynamics in the modified framework by improving groundwater dynamics in PixSWAB and testing the modified framework with other remote sensing datasets.