An integrated perspective offers novel entry points for a more fertile engagement between hydrological and social sciences across different scales ranging from the plot level to entire watersheds. Its interdisciplinary nature encompasses (and integrates) various methodological approaches, epistemologies, and disciplines.
We welcome contributions from researchers from social and natural sciences who are keen to look beyond their research perspective and who like to discuss their research findings in a broader context of coupled human water systems. Papers should
1) contribute to the understanding of complex human-water interactions and their management,
2) discuss the benefits and shortcomings of different inter- and disciplinary perspectives based on empirical, conceptual or model-based research; and
3) shed light on the added value of socio-hydrological modelling and hydro-social analysis for water resources management, risk management and adaptation design.
We specifically welcome contributions which reflect how the hydro-social and socio-hydrological research approach supports the new IAHS decade HELPING Science for Solutions aim.
Hydrological models, with or without social components, do not just represent social-hydrological systems but they afford particular ways of thinking about, deliberating on and intervening in the world. It is thus important to reflect critically on modelling practices, models and their use in water resources management.
Hydrology has a long tradition of engaging critically with models from an uncertainty perspective. I here complement this perspective with several entry points originating from the social sciences, particularly practice-theoretic and political ecology approaches.
Building on a recent special issue (Alba et al. 2025), I discuss what is special about models, how models establish authority and how models make worlds. I pay particular attention to the role of critical engagements with models in times of post-truth politics. Throughout, I connect the discussion to the ambitions of IAHS’ HELPING decade and draw out lessons for inter- and transdisciplinary water research.
References
Alba, R., T. Krueger, L. Melsen and J. P. Venot (2025). "Modelling water worlds." Water Alternatives 18(2): 214-239.
How to cite: Krueger, T.: How models intervene in the world: different entry points for engaging critically with hydrological modelling, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-20052, https://doi.org/10.5194/egusphere-egu26-20052, 2026.
Framed through an ecocritical–political ecology lens, this article examines the 2025 Pakistan floods as a socio-natural event in which rivers and floodplain ecologies act back against extractive designs. We integrate critical discourse analysis of state, media, civil-society, and community texts with GIS/remote sensing of flood dynamics, a review of policies and institutions, and semi-structured interviews (n≈20–30). Operationalizing “nature’s resistance” (hydrological, geomorphic, biological, social) against “axes of exploitation” (intensification, enclosure, hardening, neglect), we map lateral spill and avulsion near embanked reaches, backwater accumulations above major barrages, breach clustering around curvature and extractive hotspots, and wetland rebound that stores and slows flows.
Discursively, state sources privilege “act of nature” and encroachment frames, while civil society and community media emphasize infrastructural failure, governance responsibility, and climate justice. Triangulation shows how control-first paradigms concentrate risk, whereas wetland buffers and room-for-river orientations diffuse it and command local support. The study contributes a conceptual synthesis that treats the Indus as an agentive system, a mixed-methods template for socio-natural disaster research, and practical guidance for flood governance: expand floodplain room, manage sediment as infrastructure, invest in nature-based buffers, and align finance with just transitions. These insights inform equitable recovery and adaptive planning across Pakistan’s riverine provinces today.
Keywords: ecocriticism, political ecology, Indus Basin, flood governance, nature-based solutions, disaster discourse, Pakistan 2025 floods
How to cite: Riaz, M.: Ecocritical Perspectives on the 2025 Pakistan Floods: Nature’s Resistance to Human Exploitation , EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-1444, https://doi.org/10.5194/egusphere-egu26-1444, 2026.
Individual protective responses, such as preparing emergency devices and retrofitting homes, can help reduce flood damage. Risk perception is often assumed to lead to individual protective behaviour in popular theories, e.g., the Protection Motivation Theory. Yet, empirical studies show weak positive, no, and even negative correlations between risk perception and protective behaviour. This inconsistent relationship is often attributed to a reverse feedback effect, assuming that the implementation of protective measures leads to a reduction of risk perception. The feedback effect has been used in various studies to explain the weak relation between flood risk perception and protective behaviour. However, the existence of the feedback has not been statistically proven in the flood risk domain, yet. Investigating this gap is challenging due to a lack of longitudinal studies, which observe individuals over time, thus being able to establish a temporal relationship between adopted behaviour and risk perception. This study thus explores the reverse feedback effects of protective responses on risk perception, using data from a three-wave longitudinal survey over 1.5 years in Vietnam. With the same reasoning, we further investigate the feedback effects of protective and non-protective responses, e.g., wishful thinking, on other cognitive factors, such as perceived social norms and coping appraisals.
Using structural equation modelling, we do not detect significant reverse feedback effects of protective responses on risk perceptions in our dataset. Neither do we find a feedback effect on social norms and coping appraisals, except for retrofitting homes: this measure increases perceived financial capacity and perceived expectation of the general society on doing so. Given the sample size and the very high retention rate of our dataset (401 initial respondents with a retention rate of 94%), it is highly unlikely that we would not detect a feedback effect with a high or medium effect size. We thus conclude that there is no medium or strong feedback effect on risk perception in our sample. Hence, other explanations should be tested, including the most basic of all: perhaps risk perception is not (always) an important driver of protective behaviour.
By contrast, the adoption of non-protective responses has a highly significant influence on many cognitive factors. Specifically, delaying and denial reduce perceptions of risk, social norms, and coping appraisals, in line with our hypotheses. Wishful thinking, by contrast, increases perceived flood consequences, social norms, and coping appraisals, but reduces perceived flood probability. Fatalism increases the perceived flood consequences and probability, but reduces perceived coping appraisals. We thus recommend that risk communication focuses also on other cognitive factors, such as coping appraisals and social norms, and not only on risk perceptions. More research on the role of non-protective responses in flood risk adaptation and communication is needed to eventually inform policy interventions. The predictive power of behavioural theories may be improved if the relationships between non-protective responses and cognitive factors are better understood. Future studies on other flooding contexts are highly recommended to contextualise our findings.
How to cite: Luu, T., Thieken, A. H., Haer, T., and Bubeck, P.: Flood adaptation: feedback effects of (non-)protective behaviour on risk perception and other cognitive factors, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-7007, https://doi.org/10.5194/egusphere-egu26-7007, 2026.
Access to water supply and sanitation services is widely recognized as a fundamental human right and a central component of human–water systems. In countries marked by persistent socioeconomic inequality, however, the provision of these services remains unevenly distributed across space, reflecting long-standing territorial and institutional disparities. Brazil represents a critical case in this regard, combining ambitious universalization targets with significant differences in access to water and sanitation infrastructure across municipalities.
This study investigates the spatial relationship between average household income and access to urban water supply and sanitation services in Brazil’s Southeast Region. The regional focus is justified by the higher completeness and consistency of sanitation data available for the year 2020, which allows for a more robust spatial analysis. Municipal-level income data from the Fundação Getulio Vargas (FGV) were combined with urban service coverage indicators from the National Sanitation Information System (SINISA), specifically the urban water supply coverage index (IN023) and the urban sewerage coverage index (IN047). The analysis was conducted in a GIS environment (ArcGIS Pro). Spatial dependence was first assessed using Global Moran’s I statistics, followed by Local Indicators of Spatial Association (LISA) to identify clusters and spatial outliers. To further explore the interaction between socioeconomic conditions and service provision, income and sanitation LISA results were overlaid, enabling the identification of municipalities where low income and limited access to services coexist spatially.
The results indicate statistically significant positive spatial autocorrelation for income, water supply coverage, and sewerage coverage, suggesting that municipalities with similar socioeconomic and infrastructure characteristics tend to cluster geographically. The combined cluster analysis highlights territorially structured inequalities, including areas characterized by the simultaneous presence of low income and deficient access to water and sanitation services, as well as spatial mismatches where service coverage and income levels diverge. These patterns indicate that disparities in access are not randomly distributed, but instead reflect broader socio-spatial dynamics shaping human–water interactions in the region.
By adopting a human–water systems perspective, this study emphasizes that access to water and sanitation services is closely linked to territorial and socioeconomic conditions. The findings reinforce the importance of incorporating spatial and socioeconomic criteria into water and sanitation planning and demonstrate how spatial statistical approaches can support more equitable and evidence-based public policy design.
How to cite: Taroco, M. Z., Lima, C. H. R., and Almeida, V. N.: Socioeconomic inequality and access to urban water and sanitation services in Brazil’s Southeast Region: a spatial analysis from a human–water systems perspective, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-3166, https://doi.org/10.5194/egusphere-egu26-3166, 2026.
Traditional socio-hydrology models often simplify the human domain, treating populations as homogenous and overlooking disparities that shape real-world flood vulnerability and recovery. This work introduces a socio-hydrology modeling framework that explicitly incorporates community-level differences in adaptive capacity, defined as the degree to which communities can cope with flood events. In this framework, a city is treated heterogeneously, with individual communities having their own characteristics. Using empirical socioeconomic data from diverse metropolitan areas, we parameterize a new Resilience domain to represent inter-community variation in flood recovery, economic growth, and disaster response. Results reveal that disparities in economic conditions between communities can shape resilience outcomes—consistent with Kuznets curve dynamics, where early economic growth may widen recovery gaps before eventual convergence. Additionally, we differentiate between inter- and intra- community inequalities that exacerbate recovery trajectories from temporally compounding flood events. Our results emphasize how empirically based metropolitan socio-economic characteristics shape causal relationships in social-hydrological systems. We show that by incorporating community specific characteristics, city-wide adaptive capacity performance follows the Kuznets curve hypothesis, where increasing economic productivity may unintentionally widen flood resiliency disparities. We further identify how flood resiliency inequalities stem from inter-city, intra-city, and exposure disparities, highlighting how community specific information influences human-flood interactions. Additionally, our model includes an adaptive disaster relief mechanism to simulate the impacts of different resource allocation and response strategies, highlighting how equitable disaster relief policies can reduce resource gaps without compromising overall city growth. By embedding adaptive human behavior, inequality, and policy levers into a systems modeling framework, this study advances socio-hydrology as a tool for assessing coupled human-natural systems in multi-sector dynamics contexts. Our findings underscore the importance of moving beyond average or fixed representations of human systems to inform more equitable and effective urban flood resilience strategies.
How to cite: Preisser, M. and Passalacqua, P.: Adaptive Capacity Disparities: Capturing Resiliency Inequalities in Socio-Hydrological Systems, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11114, https://doi.org/10.5194/egusphere-egu26-11114, 2026.
Agricultural insurance is promoted as a drought-risk management tool, yet evidence on its long-term socio-hydrological impacts and its interactions with other adaptations is mixed, with studies reporting both increased and decreased adaptation uptake due to insurance. We extend the Geographical, Environmental and Behavioural model (GEB)—a fully distributed hydrological model coupled with an agent-based model (ABM), a process-based crop model, and a dynamic farmer adaptation module—by adding two adaptation options (well adoption, crop switching) and two insurance products (traditional indemnity, index insurance). We calibrate the model to an Indian river basin and compare outcomes across hydrological, economic, and risk-oriented metrics. Traditional insurance increases well adoption and profits, but induces lock-in to wells and higher-water-use crops, resulting in 20–50% higher annual water use and 30–60% lower groundwater levels. Index insurance avoids this lock-in, shifts production toward lower-water options, and delivers higher profits with lower basin-wide water use. However, traditional insurance sustains greater crop diversity and a more diffuse irrigation portfolio via groundwater, reducing drought risk: profit variability and losses during consecutive droughts are smaller than under index insurance (~0.039 vs ~0.085 USD m⁻²; ~20% vs ~28%). Spatial patterns indicate that insurance interacts with reservoir effects: uptake is lower in surface-water command areas, whereas index insurance shows relatively higher uptake in these zones, suggesting potential to offset reservoir effects. Finally, we find that the level of available irrigation, rather than simple access, determines whether reservoir effects emerge. Overall, the results show a design trade-off: hydrological and economic outcomes favor index insurance, while risk outcomes can favor traditional insurance, illustrating how ABMs can make these trade-offs explicit.
How to cite: Kalthof, M., Di Baldassarre, G., Aerts, J., De Moel, H., and De Bruijn, J.: Beyond Profit: Modelling the Socio-Hydrological Impacts of Agricultural Insurance and Drought Adaptation, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-10977, https://doi.org/10.5194/egusphere-egu26-10977, 2026.
Safe and reliable drinking water underpins health, livelihoods, and water security. The way in which water is accessed is an integral component of human-water systems, influencing multiple aspects of water security such as reliability, contamination risk, accessibility, and cost, and influencing hydrological dynamics through patterns of abstraction. Understanding the diversity of water sources is particularly important in low and middle income countries (LMICs), where many households obtain water through direct abstraction that is often unregulated and forms an “unseen” demand within hydrological systems.
To enable global progress tracking, international monitoring has largely classified drinking water sources into two broad groups: “improved” and “unimproved.” While useful for benchmarking access and supporting cross-country comparison, this binary categorisation conceals major functional differences in how and where water is accessed, and obscures distinct vulnerabilities that influence both human wellbeing and hydrological systems. For example, piped networks, boreholes, tanker delivery, and rainwater collection exhibit fundamentally different abstraction patterns and vulnerabilities yet are grouped as “improved,” limiting functional understanding of complex human-water interactions. Despite the importance of drinking water access as the most foundational interface between people and hydrological systems, spatially explicit information on water source types remains limited.
Using geolocated household survey data from Demographic and Health Surveys (DHS) for 53 countries (2010–2024), we produce high resolution (5km) maps of nine functionally meaningful water source groups for LMICs. A multivariate random forest model with spatial cross-validation and global biophysical and socioeconomic covariates is then used to generate 5 km gridded probability estimates of water source use. Model performance is evaluated using hold-out validation and national-level comparisons to Joint Monitoring Programme (JMP) estimates to support validation in countries lacking geolocated data.
Our results reveal large subnational variability in drinking water source types that is masked by improved/unimproved metrics. Notably, while the improved/unimproved dichotomy broadly reflects microbial contamination risk, it fails to capture vulnerabilities related to other dimensions of water security such as reliability, accessibility, and affordability. Maps also highlight hotspots of direct groundwater and surface water abstraction, illustrating where household-level abstraction is particularly important for understanding hydrological systems. By moving beyond the improved/unimproved dichotomy, this work provides new evidence to support hydrological modelling, exposure and vulnerability assessment, and strengthens the basis for integrating human water use into water security assessments.
How to cite: Hinton, R., Fridman, D., Willaarts, B., and Kahil, T.: Source matters: spatial modelling of drinking water sources and vulnerabilities in LMICs, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-9742, https://doi.org/10.5194/egusphere-egu26-9742, 2026.
Global groundwater sustainability is a grand challenge that requires diverse approaches to account for local contexts. Yet, global groundwater assessments often focus solely on aggregate physical trends in storage, levels, and fluxes, overlooking the diversity of social and ecological functions provided by groundwater and their associated sustainability challenges.
Here, we introduce groundwater sustainability puzzles as a concept and approach to identify distinct configurations of human-groundwater system sustainability challenges within heterogeneous landscapes. We apply this new concept and synthesize 17 global datasets on groundwater functions in social-ecological systems (e.g., groundwater-dependent ecosystems, irrigation, climate coupling, etc.) and groundwater system management problems (e.g., depletion, land subsidence, land use change, gender inequality, etc.) through a leading high-dimensional spatial data classification methodology that implements self-organising maps. This data-driven synthesis represents the most comprehensive integration of current data relevant to the global challenge of groundwater sustainability, and generates a refined portrait of the multi-dimensional composition, spatial organization, heterogeneity, and variance of groundwater sustainability challenges worldwide.
In total, we identify and map over 200 groundwater sustainability puzzles worldwide. Each puzzle represents a unique configuration of system functions and management problems, corresponding to a specific setting in which sustainability transformations must take root. Notably, half of global land area, population, and crop production situate within fewer than 20 puzzles respectively, indicating a more tractable problem space than the mapping might initially suggest.
Groundwater sustainability puzzles help to articulate a coherent system-of-systems problem statement for global groundwater sustainability, bridge the narratives and patterns of global groundwater analyses with local groundwater realities, and strengthen solution networks among researchers and practitioners working in similar contexts. More broadly, the approach offers a new tool for socio-hydrological and hydro-social research to compare systems across regions, facilitate cross-regional learning and network formation, and support context-appropriate pathways to sustainability across freshwater systems.
How to cite: Huggins, X., Gleeson, T., Famiglietti, J. S., Moore, M.-L., and Villholth, K. G.: Global groundwater sustainability puzzles: a coupled human–groundwater systems approach to identify distinct management challenges, strengthen solution networks, bridge global and local scales, and enable pathways to sustainability, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-13202, https://doi.org/10.5194/egusphere-egu26-13202, 2026.
India is the world’s largest consumer of groundwater for irrigation. Census data reveal an increasing trend in the number of deep tubewells being constructed, raising concerns for the sustainability of groundwater resources. Where regulatory limits on the number of wells or extraction volumes are absent, energy policies governing the availability of electricity for pumping may present an alternative tool for groundwater management, but their effectiveness remains unclear. Eastern India, a region that historically lacked groundwater development despite being touted as possessing great potential for irrigation expansion, has witnessed a recent increase in deep-well drilling even in the absence of electricity subsidies that promoted irrigation expansion in other parts of the country. Here, we study this paradox and its potential implications for sustainability using a novel longitudinal dataset combining hydrogeological and socioeconomic data. We study the growth in irrigation infrastructure between 2000 and 2018, its impact on current and future groundwater stocks and accessibility, and the influence of energy pricing mechanisms for groundwater management. We also examine the geographic distribution of well expansion and its impact on the spatial extent and intensity of cropping activities. Drawing insights from physically based groundwater modeling and econometric analysis, our results underscore the tension between irrigation development to support food security, livelihoods, and the threat of runaway groundwater depletion. Our results also highlight the limitations of using energy pricing as the primary lever for groundwater governance. Lastly, we find that the expansion of wells is uneven across lines of existing socioeconomic inequities in caste and land ownership, emphasizing the need for groundwater governance policies to be anchored not just on hydrogeological factors but on socioeconomic drivers as well.
How to cite: Gupta, I., Ray, S., and Soriano Jr., M.: Between groundwater sustainability and irrigation expansion: Evidence from eastern India, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-18350, https://doi.org/10.5194/egusphere-egu26-18350, 2026.
Dowsing is an ancient practice that employs rods or pendulums to locate groundwater and other subsurface features. Although it dates back several millennia and remains widely used today—by private individuals and, in some cases, by municipalities to locate the most easily accessible groundwater sources—dowsing relies largely on intuition and experiential knowledge rather than controlled scientific experimentation. This contrasts with hydrogeology, which emerged as a scientific discipline in the 19th century and is based on empirical observation, modeling, often complemented by other scientific disciplines, which involves significant costs. Field demonstrations of dowsing can appear convincing and are often viewed as cost-effective methods of selecting a location for drilling a new well; however, in regions characterized by sufficient rainfall and favorable geological conditions, groundwater is often ubiquitous. This raises questions about what constitutes a genuine “detection” and complicates meaningful comparisons between traditional and scientific approaches.
In addition to general groundwater, dowsers frequently claim the ability to detect underground drains or pipes. These discrete, well-defined targets provide a more suitable basis for controlled experiments and statistical evaluation. In this context, we present the final results of a controlled dowsing experiment co-designed by a multidisciplinary team of scientists in collaboration with an experienced dowsing practitioner, with the aim of ensuring both methodological rigor and acceptance by the dowsing community.
The experimental setup consisted of a grid divided into 25 cells, within which various objects were buried in selected locations. These objects included iron and plastic pipes, either empty or filled with water. When present, the water varied in composition and conditions, including saline or fresh water, as well as stagnant or flowing water. Participants were asked to scan the grid using either wooden or metal rods and to indicate the cells in which they believed an object was buried.
A total of 54 participants took part in the experiment: 27 with intermediate to extensive prior experience in dowsing, and 27 novices who received basic training before participation. Several participants completed multiple trials to assess reproducibility. The results are analyzed and discussed as a function of object type, dowsing instrument, and prior experience level, providing a quantitative assessment of dowsing performance under controlled conditions.
How to cite: Bordeleau, G., Lévesque, M., Gloaguen, E., and Giroux, B.: Testing Tradition: A Controlled Study on Dowsing Accuracy, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-3985, https://doi.org/10.5194/egusphere-egu26-3985, 2026.
Socio-hydrological and hydro-social research seeks to understand how water-related risks emerge from dynamic interactions between hydrological processes and social systems. In coupled human–flood systems, resilience-relevant dynamics include processes of long-term social learning and forgetting, the persistence and decay of adaptive capacity, and shifts in societal sensitivity that shape social vulnerability. While human–flood feedback models have improved the representation of non-stationary flood risk, adaptation dynamics are often treated implicitly or as static attributes, limiting insight into these long-term social processes.
We advance a conceptual socio-hydrological modelling framework in which adaptation as part of social vulnerability is explicitly represented as a dynamic system property, consistent with the IPCC AR6 risk framework. By foregrounding vulnerability, the framework enables exploration of resilience-relevant dynamics in coupled human–water systems. The approach highlights the added value of socio-hydrological modelling for interpreting long-term flood-risk dynamics and adaptation pathways, in line with the IAHS HELPING Science for Solutions agenda.
How to cite: Garcia-Santos, G., Wickramasinghe, R., Chetia, A., and Nakamura, S.: Advancing conceptual modelling to explore resilience-relevant dynamics in coupled human–flood systems, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-15519, https://doi.org/10.5194/egusphere-egu26-15519, 2026.
Despite tremendous progress in water resources research, technologies, and management, the world is still facing a worsening water crisis. Over 4 billion people lack access to safe drinking water and to safely managed sanitation. Water quality problems due to emerging pollutants, diffuse source pollution, and the spread of invasive species persist globally, and floods and droughts continue to cause huge economic losses and loss of life. Scholars have suggested that the global water crisis is largely a crisis of governance, and that the missing links are effective interactions between researchers and decision makers and systems thinking at multiple scales that are actionable across multiple governances. Here, we promote the integration of systems thinking to couple science, technology, society, politics, policy and management to tackle global water challenges. We identify four key governance priorities to enable the systems approach:1) leadership across multiple institutions; 2) organizations with nested structures and functions to foster long-term institutional capability to implement, monitor and assess solutions, compatible cross agency, sector, and boundary planning and management; 3) platforms for regular, effective, and dynamic discussion, exchange, and interaction among stakeholders for shaping water issues, goals, solutions, methods, and schedules; and 4) multi-level education to promote sustainable value, recognize inequality, and facilitate water saving and protection. Integration and institutionalization of these four key elements across scales, systems, sectors, and boundaries holds the promise to address the global water crisis and ensure a safe, just, and sustainable human-water system for all.
How to cite: He, C., Holden, J., Tillotson, M. R., Mitchell, G., Paavola, J., JOrtega-Martin, J., MacDonald, G., Brown, L., and Mdee, A.: Integration of Systems thinking to Couple Science, Technology, Society, Politics, Policy and Management for Sustainable Water Resources Management, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-3191, https://doi.org/10.5194/egusphere-egu26-3191, 2026.
Large-scale ecological restoration represents a profound human-driven land-use and water management change in semi-arid environments, reshaping coupled human–water systems through complex feedbacks among land use, hydrology, and ecosystem productivity. However, the integrated socio-hydrological consequences of such changes remain insufficiently quantified at regional scales. Here, we synthesize recent empirical evidence from the Loess Plateau and the Mu Us Sandyland in northern China to assess how ecological restoration and related human activities alter soil erosion, water resources, carbon redistribution, and land productivity. Using multi-source remote sensing, socio-economic statistics, GRACE satellite observations, and process-based modelling frameworks, we quantify long-term changes in soil erosion, evapotranspiration (ET), terrestrial and groundwater storage, soil organic carbon (SOC) redistribution, and gross primary productivity (GPP) over the past four decades. Results show that vegetation restoration and ecological infrastructure have substantially reduced soil erosion and enhanced land productivity across the Loess Plateau, particularly since 2000. Concurrently, erosion-induced lateral SOC transport decreased by approximately 21%, indicating a strong coupling between erosion control and regional carbon dynamics. However, these ecological gains are accompanied by increasing water demand. Vegetation greening emerged as the dominant driver of rising ET and GPP, while ecological restoration, irrigation expansion, and mining activities jointly accounted for nearly 80% of observed terrestrial and groundwater storage decline in water-limited regions. These findings reveal reinforcing and counteracting feedbacks in human–water systems, where ecological restoration simultaneously improves ecosystem services and intensifies water stress. Our study highlights the necessity of integrating hydrological constraints into ecological restoration planning and provides socio-hydrological insights for balancing environmental recovery, water sustainability, and human development in semi-arid regions.
How to cite: Gou, F.: Integrated human–water–carbon feedbacks driven by large-scale ecological restoration in semi-arid northern China, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-4867, https://doi.org/10.5194/egusphere-egu26-4867, 2026.
Socio-hydrology has emerged as a critical framework for Integrated Water Systems (IWS) management, emphasising the need to bring governance, policy, and institutional dynamics alongside physical and technical processes. Achieving meaningful integration between social and technical domains presents both epistemological and methodological challenges, requiring the coexistence of quantitative and qualitative forms of knowledge and the development of hybrid, co-creative modelling approaches. Recent advances in Large Language Models (LLMs) offer new opportunities to address this socio-technical divide. These systems can process heterogeneous data sources such as text, images, and video, and translate qualitative information into representations that can be systematically analysed alongside numerical model outputs. LLMs can be embedded within agentic frameworks and be applied to emulate aspects of human reasoning, interaction, and decision-making. This enables the exploration of social behaviours and institutional responses within complex IWS contexts. Our study reviews existing applications of LLMs in IWS research and categorises them according to their use of LLM affordances, particularly in terms of agentic autonomy and the nature of simulated social interactions. Building on this review, we propose a novel approach that employs LLM-based agents as interpretative intermediaries between IWS simulation outputs, policy documents, and stakeholder relationships in decision-making scenarios. Applying such systems to real-world water management problems and conducting statistical and comparative analyses can reveal previously inaccessible relationships and dependencies between social and technical components of IWS, supporting more integrated and adaptive water governance.
How to cite: Rico Carranza, E. and Mijic, A.: The application of LLM agentic frameworks as a bridge between social and technical domains in Integrated Water Systems management., EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-11295, https://doi.org/10.5194/egusphere-egu26-11295, 2026.
Water storage systems are crucial for achieving several Sustainable Development Goals amidst evolving climatic and societal conditions. Today, over 58,000 large dams regulate about 46% of the world’s main rivers, which are shaped by both their inherent hydrologic patterns and the choices made by human sectors, who determine how much water to hold in reservoirs and how much to release for different stakeholders’ needs. While mathematical models for water resources processes benefited from centuries of study and development across spatial and temporal scales, the research on human behavioural models and their integration in socio-hydrology frameworks are less advanced. Thus, there is a pressing need to highlight the critical role of human behaviours concerning water systems with coexisting and conflicting water purposes, asking for more accurate and valid water balance simulations when exploring alternative, robust water management strategies able to satisfy competing and multisector societal needs.
In this context, the BERLIN project aims to construct innovative behavioural models of the human intentions and preferences by leveraging the recent advances in Machine Learning, which allow exploiting the full potential of the unprecedented availability of big observational data, with insights from Social Learning, incorporating stakeholders’ experiences and preferences from a triple-loop approach (risk awareness, risk perception, and risk adaptation) to reinforce the model-based exploration of adaptation policies. Their combination in different climate change hotspots representing semiarid regions, river deltas, and snow-dependent river basins will support the development of behaviourally explicit hydrologic models, providing rigorous retrospective assessments of observed decision-making processes and the generation of reliable and credible projections of the future co-evolution of complex water systems. At the same time, BERLIN will promote knowledge exchange by involving key stakeholders through co-creation processes, collaborative frameworks, and participatory indicators, ensuring that place-based knowledge and end-users’ priorities are embedded in global modelling efforts.
Particular emphasis will be dedicated to elucidating how water systems and societies co-evolve through feedbacks between hydrological dynamics, infrastructural operations and institutional/behavioral drivers. For this purpose, socio-hydrological modelling and hydro-social analysis become increasingly more important to unpack how policies, risk perceptions, inequality, and power-interest (im)balance shape water availability, hazards, and resilience over time. From a sociohydrology perspective, these approaches improve water resource allocation, sustainability, and conflict resolution by integrating human decision-making with physical processes. From a hydrosocial research angle, they support context-specific, equitable, and robust strategies that anticipate behavioral responses, unintended consequences, and long-term dynamics under uncertainty and change across scales and decision-making settings, thus supporting better water resource governance.
Against this background and aligned with the HELPING vision of the Science for Water Solutions Decade, BERLIN promotes anchoring hydrological science in real-world decision-making processes and integrating global datasets with national and local information sources, including in-situ observations. The integration of sociohydrology and hydrosocial research concepts and methods contributes to the understanding of the key interactions and potential loops between global drivers and locally specific water management and governance challenges, explicitly accounting for human responses, non-linear dynamics, feedbacks, and evolving system trajectories.
How to cite: Tagliacozzo, S., Al-Khasawneh, L., Jin, S., Ricart, S., and Giuliani, M.: The BERLIN project: Delving into behavioral modelling for evidence-based adaptation policies under complex human-water interactions, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-6465, https://doi.org/10.5194/egusphere-egu26-6465, 2026.
Unequal water access will be a major driver of increasing water insecurity in the 21st century, exacerbating the impacts of climate change. An estimated one billion people in cities in low- and middle-income countries currently face varying degrees of public water supply interruptions, subjecting them to unequal water access. This number is expected to grow, as water scarcity intensifies and supply infrastructure deteriorates. Yet, insights into the quantitative effect of water supply intermittency on urban water access inequality are so far limited. Here, we assess insights from hydro-economic multi-agent modeling case studies in South Asia and in the Middle East to analyze the effects of intermittent public water supply on the water security of heterogeneous urban household populations. We find that public water supply interruptions lead to severe disparities in household water consumption across cases. This also leads to household reliance on costly alternative water sources, jeopardizing water affordability. By 2050, climate change and population growth exacerbate the effects of water supply intermittency, causing severe deterioration in water security and increasing water access inequality. The results indicate that improved monitoring of water access inequality and reducing supply intermittency are key to mitigating urban water insecurity in the coming decades.
How to cite: Klassert, C., Yoon, J., Wang, A., Zhu, Y., Reyes Vásquez, J., Talozi, S., Hernández Suarez, J. S., Khan, H. F., and Gorelick, S. M.: Public water supply intermittency and unequal urban water access: Insights from hydro-economic multi-agent modeling case studies in the Global South, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-15377, https://doi.org/10.5194/egusphere-egu26-15377, 2026.
Urban drainage networks (UDNs) constitute essential infrastructure for mitigating urban flooding hazards and public health risks by collecting and conveying stormwater and wastewater. Accordingly, much of the existing literature has focused on improving UDN functional performance, typically through detailed process-based modeling approaches. While these methods have substantially advanced UDN design and operational analysis, their intensive data requirements and high computational costs have highlighted the need for complementary perspectives that can infer UDNs’ functional characteristics directly from network topology. Flows within UDNs are predominantly gravity-driven and organized along converging drainage paths, analogous to those observed in natural river networks. This physical resemblance implies fundamental commonalities in the structural organization of UDNs and rivers, motivating the characterization of UDN topology using scaling laws originally found from river networks in a concise and physically grounded manner. Building on this perspective, recent studies have shown that UDNs exhibit self-similarity analogous to that of natural river networks. These findings naturally prompt further inquiry into: (1) To what extent do scaling properties represent a homogeneous feature of UDN topologies? (2) If not, how should heterogeneity in scaling properties be interpreted through functional or physical perspectives? To address these questions, we analyzed ~220 UDNs (~4,000 km) constructed in Seoul (~605 km², ~9.7M people), South Korea, a representative megacity in Asia. Three classical scaling features identified in river networks were applied to UDNs: (i) power function in the area-length relationship (scaling exponent h), (ii) power function in the area exceedance probability distribution (scaling exponent ε), and (iii) a set of Hortonian scaling ratios (i.e., bifurcation, length, and area ratios). For the interpretation of scaling properties in UDNs, we considered ~20 descriptive indicators covering topographic, geometric, structural, and socio-economic domains. We found heterogeneity in the studied UDNs’ scaling properties. First, the power-law scaling exponents, h and ε, exhibited broader distributions and smaller values (0.2 < h < 0.9; 0.05 < ε < 0.41), respectively, compared to those typically reported for natural river networks (0.5 < h < 0.7; 0.40 < ε < 0.46). This reflects the influence of urban constraints, including road layouts and building distributions. Moreover, only about half of the analyzed UDNs simultaneously satisfied the three Hortonian scaling ratios, indicating that hierarchical scaling is not a universal property for UDNs. This heterogeneity in hierarchical scaling is closely linked to network size, drainage efficiency, structural maturity, and specific socio-economic characteristics. Our findings are expected to not only provide a fundamental basis for coupling the structural and functional characteristics of UDNs but also offer a conceptual foundation for bridging the gap between network topology and functional resilience in UDNs.
Acknowledgements
This work was supported by the Creative-Pioneering Researchers Program through Seoul National University and by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (No. RS-2025-00523350).
How to cite: Kim, H. and Yang, S.: Deciphering Heterogeneous Scaling Properties in Urban Drainage Networks, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-2902, https://doi.org/10.5194/egusphere-egu26-2902, 2026.
Urban drainage networks (UDNs) are essential public infrastructure systems responsible for the conveyance of stormwater and wastewater. With intensifying urbanization, UDNs have evolved into structurally complex systems whose functional organization is not adequately resolved by conventional graph-based representations. This limitation necessitates a conceptual shift from structure-centric analyses toward functionality-informed topological approaches. One such approach represents UDN layouts within a dual-mapping domain, in which pipe segments conventionally treated as edges are redefined as nodes, while their intersections are encoded as edges. Transformations into the dual-mapping domain enable network-scale comparisons, and facilitate to uncover emergent features of diverse individual complex networks, even further co-evolutionary self-similar characteristics among various networks. These features are captured in the power-law relationship between the dual-node degree k and its probability P(k) with an exponent γ, i.e., P(k) ~ k -γ. Nonetheless, little is known about the physical and mechanistic interpretation of the scaling exponent γ, although its values have been extensively reported across different infra-networks. In addition, dual-mapped representation commonly relies on the Hierarchical Intersection Continuity Negotiation (HICN) method; however, as this method was originally designed for road networks, it fails to capture the convergent and flow-directed nature of UDNs. Consequently, unmodified application of the HICN method can result in unintended merges, disconnections and non-reproducible dual representations. To address these conceptual and methodological limitations, this study adopts the Horton-Strahler order as a constant hierarchical criterion and integrates flow-aligned continuity criterion for merging pipe segments. We further elaborate the understanding of the UDNs’ dual-degree distribution by (1) analytically deriving γ as a function of Horton’s bifurcation and segment ratios in ideal Hortonian networks and (2) interpreting this relationship through fractal dimension to enable quantitative links between scaling and topology. Our analytical results are validated using ~ 200 UDNs in Seoul, Republic of Korea, alongside synthetic drainage networks simulated by Gibbs-model. We find two distinct topological architectures of the dual-mapped UDNs that exhibit either a single or double power-law scaling. While ~50% of the Seoul UDNs and the synthetic networks exhibited self-similarity consistent with ideal Hortonian networks, the dual-node degree distributions of the remaining networks were better described with double power-law characteristics. This double power-law behavior serves as a critical indicator of network heterogeneity, quantitatively reflecting engineering factors such as variations in pipe-type composition, sub-catchment density, and redundancy in critical conduits. Overall, the proposed method significantly improves reproducibility and strengthens the physical interpretability of complex-network indicators, offering a robust tool for monitoring UDN evolution under the pressures of urban expansion.
Acknowledgements
This work was supported by the Creative-Pioneering Researchers Program through Seoul National University and by the National Research Foundation of Korea (NRF) grant funded by the Korean government (MSIT) (No. RS-2025-00523350).
How to cite: Lim, J. and Yang, S.: Emergent heterogeneous scaling regimes in the functional topology of urban drainage networks, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-6422, https://doi.org/10.5194/egusphere-egu26-6422, 2026.
Anticipating future water security is essential for sustainable development, food security, and economic stability across regions and sectors. Water scarcity and abundance are increasingly shaped by the combined effects of socio-economic development and climate change, yet their spatial patterns under deep uncertainty have not yet been systematically explored, particularly for regions such as Thuringia in Germany, which has historically been considered water abundant. Previous studies have typically assessed water scarcity using single-sector models or limited scenario frameworks, neglecting sectoral and regionally specific patterns of change. This limits our ability to identify regions that may remain water abundant despite profound change.
This study examines where and to what extent water scarcity and abundance emerge under combined socio-economic and climatic change, and how robust these outcomes are under deep uncertainty. We show that explicitly representing interacting water users within a multi-agent hydro-economic framework fundamentally alters the projected spatial distribution of future water stress and surplus.
Using a high-resolution multi-agent system (MAS) that integrates industrial, household, and agricultural water demands within a large-scale model of Thuringia, we construct an ensemble of water-use trajectories coupled with soil moisture projections from mHM as well as groundwater and surface water projections. These trajectories combine policy adjustments with regionalized SSP–RCP scenarios of population development, GDP, agricultural prices, and climate impacts. We employ econometric water demand functions for industrial water use across 19 districts and household demand across 800 water supply areas. Agricultural water use is represented through the coupled hydro-economic model DroughtMAS, comprising more than 1000 representative agricultural agents calibrated via Econometric Mathematical Programming (EMP) and driven by projected yield anomalies under droughts and hydro-climatic extremes, which are derived from a LASSO-regression–parametrized yield model.
Our results reveal that despite overall declining water use, localized changes—such as urban growth, increasing irrigation demand, and regional declines in water availability —can intensify potential water scarcity. In a broader context, these findings demonstrate that future water risk is not solely climate-driven but driven by a combination of socio-economic development pathways and policy choices. Accounting for these dynamics is therefore critical for identifying resilient regions and developing robust water governance under uncertainty, and provides a framework to explicitly quantify water abundance alongside scarcity within a coupled socio-economic and hydro-climatic system.
How to cite: Werner, S., Klassert, C., Wijenaykae, D., Heileman, J., Digman, E., Klauer, B., and Gawel, E.: Capturing Water Scarcity and Abundance under Change: A Multi-Sector Hydro-Economic Scenario Ensemble Approach for Thuringia, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-19699, https://doi.org/10.5194/egusphere-egu26-19699, 2026.
Numerical models play a critical role in socio-hydrology, influencing decisions that impact coupled human-water systems. For instance, policy decisions on the allocation of water increasingly rely on hydrological and hydro-economic models that structure the framing of scarcity, priority uses, and the acceptable trade-offs. This, in turn, has wider-reaching effects on both economic uses and hydrological systems as well as biophysical processes in the affected areas. In all of this, models are often seen as neutral entities providing objective information. However, subjectivity arises from assumptions of what is important to model, theories of human behaviour, technical model choices, and uncertainties. Understanding the socio-natural feedback between biophysical states, the assumptions that influence models, and the models’ roles in shaping water governance is crucial to improving transparency and, ultimately, in highlighting potentially more just and sustainable allocations of water that better meet the needs of people and the environment. This research examines the socio-hydrological role of models in the allocation of water resources by understanding models as socially constructed and therefore non-neutral tools that engender or favour certain types of outcomes over others. It takes as a case study the semi-arid Piancó-Piranhas Açu (PPA) Basin in Northeast Brazil, in which allocation of water is an ongoing, negotiated process. This process has been made more complex by a large-scale inter-basin transfer project bringing water to the PPA, resulting in overlapping authority (federal, state, basin committee) interacting to allocate and manage water. It also fundamentally alters hydrological processes in both basins. This study explores the development, characteristics, and uses of models in the PPA basin during the formation of allocation rules, and how these rules have impacted coupled human-water systems. Through a social construction of technology (SCOT) framework, a grey literature analysis, and semi-structured interviews with modellers, water managers in key institutions at multiple geographic scales, and stakeholders, we reconstruct the development, configuration, and uses of key models. Challenging the notion of models as neutral decision-support tools by examining their implicit role in the framing of scarcity and the legitimisation of particular governance decisions on water allocation, the study aims to support more reflexive, transparent, and socially robust approaches to water allocation.
How to cite: Frolich, E., Whaley, L., and Orieschnig, C.: A socio-hydrological understanding of the use of models in water allocation: the case of the Piancó-Piranhas Açu (PPA) Basin in Northeast Brazil, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-12827, https://doi.org/10.5194/egusphere-egu26-12827, 2026.
The propagation of anthropogenic drought is shaped by patterns of human consumption, in turn influenced by water restrictions and public awareness. In this study, we develop a sociohydrological model to investigate how social dynamics interact with anthropogenic drought in Cape Town, South Africa, with a focus on the Day Zero water crisis. In particular, we examine how different drivers influence urban water consumption, focusing on: (1) water-use restrictions, (2) emotional narratives expressed in drought-related news media, and (3) the combined effects of water restrictions and media-driven emotional responses. By integrating hydrological dynamics with behavioral responses to policy interventions and media sentiment, the model captures feedbacks between water shortage, public awareness, and water consumption behavior. The interactions between water restrictions and media-driven emotions produce nonlinear and time-varying awareness, which in turn influence the dynamics of urban water consumption. This study underscores the role of news media narratives in influencing public behavior during drought and demonstrates the value of sociohydrological approaches for understanding urban drought risk.
How to cite: Choi, S., Di Baldassarre, G., and Kam, J.: How do drought news, emotions, and restrictions influence patterns of water consumption? The case of Cape Town and the Day Zero crisis, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-1860, https://doi.org/10.5194/egusphere-egu26-1860, 2026.
Posters virtual: Fri, 8 May, 14:00–18:00 | vPoster spot A
EGU26-14286 | Posters virtual | VPS11
How Much Water Is Embedded in Trade? A Systematic Review and Research Roadmap for Morocco under Climate ChangeFri, 08 May, 14:24–14:27 (CEST) vPoster spot A
Water scarcity across the Mediterranean is increasingly forcing economies that are deeply integrated into global markets to balance export performance with long-term water sustainability. Research on “virtual water” and trade-related water footprints has grown rapidly, yet it remains fragmented: studies rely on diverse frameworks (physical accounting, MRIO, life-cycle assessment, and hybrids), use non-uniform scarcity metrics, and often treat climate projections and adaptation only implicitly. This review asks: which methods are currently used to estimate the water footprint of trade under climate constraints, what limits their comparability, and what methodological protocol is needed for a robust, policy-relevant application to Morocco? By framing trade-related water footprints as part of coupled human–water systems, the review highlights how economic structures, trade choices, and climate-driven water scarcity interact and generate feedbacks relevant for water governance and policy design.
We follow a PRISMA-type workflow based on systematic searches in Scopus and Web of Science, with explicit inclusion/exclusion criteria and standardized data extraction. Studies are coded along five dimensions: (i) data type (monetary vs. physical); (ii) modelling approach (IO/MRIO, LCA, hybrid); (iii) treatment of scarcity (stress factors, availability indicators, scarcity-adjusted footprints); (iv) integration of climate change (scenarios, downscaling, hydrological modelling); and (v) potential to inform policy (efficiency improvements, reallocation options, abstraction caps, and economic or trade-related instruments). Institutional sources are used in a complementary way to document indicator frameworks and datasets, without replacing the peer-reviewed evidence base.
The review delivers (1) an operational typology of methods used to quantify trade-related water footprints under climate stress; (2) a diagnosis of key comparability barriers (spatial resolution, upstream embodied water through inputs, and the limited use of dynamic approaches); and (3) a practical empirical agenda linking hydrological projections, water-extended input–output frameworks, and decision-relevant scarcity metrics. Outputs will be shared through a reusable coding grid and an analytical framework diagram to support country studies and comparative work across the Mediterranean.
How to cite: Tasra, F. and Mafamane, D.: How Much Water Is Embedded in Trade? A Systematic Review and Research Roadmap for Morocco under Climate Change, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-14286, https://doi.org/10.5194/egusphere-egu26-14286, 2026.
