Valuing Groundwater Impacts for Sustainable Urban Planning in Coastal Cities

Valuing Groundwater Impacts for Sustainable Urban Planning in Coastal Cities | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Research Article Valuing Groundwater Impacts for Sustainable Urban Planning in Coastal Cities Taher Osman This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7846108/v1 This work is licensed under a CC BY 4.0 License Status: Under Revision Version 1 posted 12 You are reading this latest preprint version Abstract Groundwater is a critical yet often invisible resource underpinning the resilience of urban areas, particularly in coastal zones facing climate change. Despite its importance, groundwater is systematically undervalued and poorly integrated into urban planning and policy, leading to unsustainable development pathways. This paper introduces a novel Integrated Hydro-Economic Valuation Framework designed to make the economic consequences of groundwater changes visible and actionable for urban decision-makers. The framework links physical hydrogeological changes to impacts on urban systems and quantifies them in monetary terms. We apply this framework to a comprehensive case study of Egypt's Mediterranean coast, a rapidly urbanizing region representative of many coastal zones in the Global South. Using a high-emissions climate scenario (RCP8.5), we project rising groundwater levels due to sea-level rise and value the subsequent damages to agriculture and road infrastructure across 16 coastal units through 2100. The results reveal substantial and escalating economic costs, projected to reach billions of L.E., with over 98% of the damage concentrated in the densely populated urban and economic hubs of the Nile Delta, including Alexandria. These findings demonstrate that failing to account for groundwater changes creates a massive, unfunded liability that threatens municipal solvency and long-term sustainability. The paper concludes by providing concrete policy recommendations for integrating these valuation outcomes into risk-informed urban planning, infrastructure investment, and climate adaptation strategies. This research provides a robust, replicable methodology for cities worldwide to quantify the hidden costs of groundwater degradation and recalibrate their development trajectories for a water-secure future. groundwater urban resilience economic valuation sustainability ecosystem services climate adaptation urban planning Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 1. Introduction Groundwater, accounting for approximately 99% of all liquid freshwater on Earth, is a foundational resource for global human development and urban sustainability (IOM, 2025). It supplies nearly half of all drinking water worldwide, 43% of water for irrigation, and a substantial portion for industrial processes, supporting the livelihoods of billions (The World Bank, 2023; Jasechko & Perrone, 2018). In an era of increasing climate variability, the vast storage capacity of aquifers provides a unique natural buffer against shocks such as drought and unpredictable surface water flows (IOM, 2025; IAH, 2019). This buffering capacity has led to groundwater being described as "nature's insurance," a critical asset for enhancing the climate resilience of cities and protecting economies from water-related shocks (The World Bank, 2023; IAH, 2019). Despite this vital role, a profound paradox lies at the heart of urban development: the more cities grow, the more they depend on this invisible resource, yet the very processes of urbanization—such as surface sealing from construction, increased abstraction, and pollution from industrial and domestic waste—degrade and deplete the groundwater systems beneath them (USGS, 2025; Singh, 2012; Carreón-Freyre et al., 2022). This is particularly acute in the rapidly urbanizing Global South, where institutional and financial capacities to manage this interplay are often limited (Shrestha et al., 2020; Foster et al., 2002). Groundwater is frequently characterized by open access and is often poorly understood, leading to it being systematically undervalued and mismanaged in policy and public discourse (IOM, 2025; Foster, 2022; UN-Water, 2022). This undervaluation is not merely a conceptual issue; it has tangible and severe consequences for urban planning. The "invisibility" of groundwater is as much economic and political as it is physical. Because its services are not traded in conventional markets, groundwater is often assigned a default value of zero in the cost-benefit analyses that drive urban infrastructure investment and land-use zoning decisions (Tsur, 2000). When a city planner evaluates a new coastal development, the long-term costs of saltwater intrusion, land subsidence from over-extraction, or, as this paper explores, damage from rising groundwater levels, are typically absent from the balance sheet. This absence of a clear financial signal encourages maladaptive development patterns, exposing populations and high-value economic assets to foreseeable but un-costed risks. Furthermore, a fundamental mismatch exists between the temporal scales of urban planning, which often operates on 5- to 10-year cycles, and the slow-onset nature of groundwater system changes, which can unfold over decades or centuries (IAH, 2019). While a growing body of literature critiques the policy disconnect between water resource management and urban planning, particularly in the Global South (Shrestha et al., 2020; Garduño & Foster, 2011; Morris et al., 2000), it often lacks the quantitative, decision-relevant metrics needed to bridge this gap. This paper addresses this critical knowledge gap by developing and applying an Integrated Hydro-Economic Valuation Framework . The novelty of this framework lies in its ability to translate complex, long-term hydrogeological changes into tangible economic costs that are spatially explicit and directly relevant to urban planners, finance ministries, and infrastructure managers. By monetizing the physical damage, the framework makes the "invisible" costs of inaction visible, providing a common language—money—to facilitate dialogue and integration across traditionally siloed policy domains. This research aims to answer the following key questions: How can the economic impacts of climate-induced groundwater changes on critical urban and peri-urban systems be systematically valued? What is the potential scale and spatial distribution of these economic impacts in a representative, rapidly urbanizing coastal region under a high-emissions climate scenario? How can these valuation outcomes be translated into actionable urban planning, sustainable water management, and climate adaptation policies? To answer these questions, this paper first reviews the literature on groundwater valuation and its intersection with urban policy. It then details the Integrated Hydro-Economic Valuation Framework and its specific methodological application. Subsequently, it applies this framework to a comprehensive case study of Egypt's Mediterranean coast, a region characterized by high population density, significant economic assets, and acute vulnerability to climate change-induced sea-level rise and associated groundwater impacts. The results quantify the projected economic damage to agriculture and road networks through 2100. The paper concludes by discussing the profound implications of these findings for urban planning and policy, not only in Egypt but for vulnerable coastal cities worldwide. 2. Literature Review Understanding the economic impacts of groundwater changes on urban systems requires an interdisciplinary approach that bridges environmental economics, hydrology, and urban policy. However, the literature in these fields has often evolved in parallel, creating significant knowledge gaps. This review critically examines three key areas: the established methods for water resource valuation, the emerging frontier of valuing groundwater's ecological role, and the well-documented governance failures that prevent valuation from influencing urban policy in the Global South. 2.1 The Economic Valuation of Water Resources The economic valuation of water seeks to quantify its contribution to human welfare in monetary terms, providing a basis for efficient allocation and management (Ghosh & Bandyopadhyay, 2009; FAO, 2004). The guiding conceptual model is Total Economic Value (TEV), which categorizes value into several components. Use values derive from the direct or indirect use of the resource, such as water for irrigation (direct use) or the flood control functions of a wetland (indirect use). Non-use values capture the value people hold for a resource independent of their own use, including bequest value (for future generations) and existence value (the value of knowing a resource exists) (Arthur D. Little, 2025; FAO, 2004). To estimate these values, economists have developed three main families of methods (Abdrabo & Hassaan, 2024; IWRM Toolbox, 2025; EPA, 2018). Market-Based Approaches : These methods use market data or engineered costs to infer value. The dose-response function links a change in an environmental variable (e.g., water level) to a change in a marketed output (e.g., crop yield), valuing the impact at market prices. The replacement cost or avoided cost method values an environmental service based on the cost of replacing it with man-made technology (e.g., valuing water purification by the cost of a treatment plant) (EPA, 2018; Zhang et al., 2020). These methods are often favored for their reliance on observable data but can only capture a subset of total value. Revealed Preference Methods : These techniques infer value from observed behavior in related markets. Hedonic pricing , for instance, analyzes property values to determine how environmental amenities, such as proximity to a clean water body, are capitalized into housing prices (IWRM Toolbox, 2025; Business Case Studies, 2025). The travel cost method estimates the recreational value of a site by analyzing how much people are willing to spend to visit it (EPA, 2018). These methods are powerful for valuing specific amenities but are limited to contexts where such related market behavior can be observed. Stated Preference Methods : When no market behavior exists to reveal values (especially for non-use values), these methods use carefully constructed surveys to create a hypothetical market. The most prominent is the Contingent Valuation Method (CVM) , which directly asks individuals their willingness-to-pay (WTP) for an environmental improvement or willingness-to-accept (WTA) compensation for a loss (Ghosh & Bandyopadhyay, 2009; Loomis, 2000). While CVM is theoretically capable of capturing TEV, it is subject to numerous biases, including hypothetical bias (what people say they would pay differs from what they actually would), strategic behavior, and embedding effects, where the value stated is insensitive to the scope of the good being valued (Duberstein, 2004; Venkatachalam, 2004; Whittington, 1998). These challenges are particularly pronounced in developing country contexts, where unfamiliarity with hypothetical markets and institutional mistrust can complicate survey administration (Whittington, 1998). The choice of valuation method is therefore not merely technical but strategic; complex, data-intensive methods like CVM may be impractical in data-scarce regions, inadvertently perpetuating the very problem of undervaluation they seek to solve (Morris et al., 2000; Duberstein, 2004; MacDonald et al., 2017). 2.2 The Frontier: Valuing Groundwater-Dependent Ecosystem Services (GDEs) A significant gap in the valuation literature concerns the ecological role of groundwater. Aquifers are not merely underground reservoirs; they are ecosystems that provide critical supporting and regulating services, such as water purification, nutrient cycling, and sustaining the baseflow of rivers and the health of wetlands and other groundwater-dependent ecosystems (GDEs) (Aziz et al., 2025; Griebler & Avramov, 2015). These services are foundational to the health of broader terrestrial and aquatic ecosystems and provide immense, albeit largely unquantified, economic value (Aziz et al., 2025; Anonymous, 2024). The scientific and economic challenges in this area are substantial. Quantifying the link between a change in a groundwater regime and the functioning of a dependent ecosystem requires sophisticated, integrated hydrogeological models that are rarely available (Aziz et al., 2025). Consequently, large-scale monetary estimates for GDEs are largely absent from major ecosystem service valuation studies, representing a critical assessment gap (Griebler & Avramov, 2015). While frameworks for GDE valuation have been proposed, they often remain conceptual or are applied at a very local scale (Eamus et al., 2008). This paper acknowledges this frontier by focusing on the more tractable, direct-use values associated with agriculture and infrastructure, framing its findings as a conservative, lower-bound estimate of the total economic costs of groundwater changes. The un-valued loss of GDEs remains a critical area for future interdisciplinary research. 2.3 The Governance Gap: Policy Fragmentation in the Urban Global South Even where valuation studies are conducted, their impact on policy is often muted by deep-seated governance challenges, particularly in the rapidly urbanizing Global South. A consistent theme in the literature is the profound disconnect between water resource management and urban land-use planning (Shrestha et al., 2020; Morris et al., 2000; Water in the West, 2025). Urban, water, and climate policies are typically formulated and implemented in institutional silos, with insufficient focus on urban water security and a lack of effective interlinkages between sectors (Shrestha et al., 2020; Van der Walt et al., 2023; Wolf et al., 2007). This policy fragmentation is a direct cause of the undervaluation problem. When the Ministry of Urban Planning and a Ministry of Water Resources operate independently, the costs incurred by one sector (e.g., long-term aquifer depletion or contamination) are not factored into the benefits pursued by the other (e.g., short-term economic growth from urban expansion). This leads to what has been termed a "silent revolution" of unplanned and unmanaged groundwater exploitation that accompanies urbanization, creating long-term vulnerabilities that are not reflected in current policy priorities (Foster et al., 2002; Garduño & Foster, 2011). Key constraints identified across numerous studies include a lack of hydrogeological data, weak institutional capacity, fragmented legal frameworks, and a general failure to integrate scientific understanding of groundwater systems into spatial planning and development control (Shrestha et al., 2020; Morris et al., 2000; Minea & Călin, 2022; La Vigna et al., 2022). The challenge, therefore, is not only to value groundwater but to embed that valuation within governance structures in a way that forces integrated, cross-sectoral decision-making. 3. Conceptual Framework and Methodology: An Integrated Hydro-Economic Approach To address the policy and valuation gaps identified in the literature, this paper proposes and applies an Integrated Hydro-Economic Valuation Framework. This framework provides a structured, replicable process for translating physical changes in groundwater systems into spatially explicit economic metrics that can directly inform urban planning and climate adaptation policy. Its strength lies in its modularity and its pragmatic focus on methods that are applicable in data-constrained environments, common in the Global South. 3.1 The Integrated Hydro-Economic Valuation Framework The framework consists of a four-step, interdisciplinary process designed to bridge hydrology, economics, and urban policy (Table 1 ). Step 1: Hydrogeological Scenario Analysis. The process begins with a clear definition of the physical stressor on the groundwater system. This requires input from hydrogeological models that project changes in key groundwater parameters (e.g., water table depth, salinity) over a defined time horizon and under specific drivers, such as climate change scenarios (e.g., RCPs), land-use change, or extraction patterns. Step 2: Impact Pathway Identification. This step maps the causal chain from the physical hydrogeological change to specific, tangible impacts on human systems. It requires identifying the key urban and peri-urban assets and economic activities that are sensitive to groundwater conditions. Examples include waterlogging of agricultural lands, saturation of road sub-bases, corrosion of subterranean infrastructure, damage to building foundations, and degradation of GDEs. Step 3: Economic Quantification. This step applies appropriate economic valuation techniques to monetize the physical impacts identified in Step 2. The choice of method depends on the impact pathway and data availability. The framework prioritizes pragmatic, data-driven methods such as dose-response functions and replacement cost analysis, which are more readily applicable in many developing country contexts than complex stated preference surveys. Step 4: Spatially Explicit Policy Analysis. The final step involves disaggregating the total economic costs and analyzing their distribution across relevant administrative and planning units (e.g., municipalities, coastal management zones). This spatial analysis is crucial for identifying hotspots of vulnerability, prioritizing investments, and tailoring policy interventions to the specific risk profiles of different urban and rural areas. Table 1 The Integrated Hydro-Economic Valuation Framework Step Description Key Inputs Key Outputs 1. Hydrogeological Scenario Analysis Define and model the physical change in the groundwater system over time. Climate projections (e.g., SLR), land use models, extraction data, hydrogeological models. Spatially explicit maps of projected changes in groundwater levels, quality, etc. 2. Impact Pathway Identification Link physical groundwater changes to specific impacts on urban assets and economic sectors. Asset inventories (infrastructure, buildings), land use maps, agricultural data. A matrix of assets at risk and the mechanisms of impact (e.g., waterlogging, subsidence). 3. Economic Quantification Apply valuation methods to monetize the physical impacts in a common unit (currency). Market prices (crops, construction), engineering cost data, dose-response functions. Monetary estimates of damage costs over time (e.g., agricultural losses, infrastructure repair costs). 4. Spatially Explicit Policy Analysis Analyze the spatial distribution of economic costs to inform targeted policy and planning. GIS data of administrative boundaries, valuation results from Step 3. Vulnerability maps, risk-based zoning recommendations, prioritized investment plans. 3.2 Valuation Methodology for the Case Study The application of this framework to Egypt's North Coast utilizes two primary valuation methods, as detailed in the technical assessment for the region (Abdrabo & Hassaan, 2024). These methods were selected for their robustness and reliance on available engineering and economic data as shown in Table 2 . 3.2.1 Valuing Agricultural Impacts (Dose-Response Function) The impact of rising groundwater levels on agricultural productivity is valued using a dose-response or production function approach. This method establishes a quantitative relationship between the environmental stressor (high groundwater table) and the economic output (crop yield). Principle : Optimal agricultural yield requires groundwater to be at a sufficient depth below the root zone. As the water table rises, it leads to soil saturation, poor aeration, root damage, and the growth of fungi, all of which reduce crop productivity and can ultimately cause plant death (Abdrabo & Hassaan, 2024). Methodology : The relationship between groundwater depth and yield reduction was calibrated using segmented polynomial regression based on data from various literature sources. This resulted in specific functions for two main agricultural categories: field crops and fruit trees (Abdrabo & Hassaan, 2024). For crops, the reduction rate in yield (y) as a function of groundwater level (x) is given by y = 6.6233x3 − 44.59x2 + 107.67x + 0.4618 For fruit trees, the function is: y = 7.42x3 − 51.481x2 + 119.81x − 0.7439 Damage Cost Calculation : The total damage cost to agriculture (Dc​) is then calculated by multiplying the projected yield loss by the value of the agricultural output in the vulnerable area. The formula applied is: Dc​=Pp​×Av​×100y​, where Pp​ is the average productivity per unit area of cultivated land (projected based on GDP growth), Av​ is the vulnerable cultivated area exposed to a given groundwater level, and y is the percentage reduction in yield derived from the functions above (Abdrabo & Hassaan, 2024). 3.2.2 Valuing Infrastructure Impacts (Replacement Cost Method) The damage to road networks is valued using the replacement cost method, which estimates the value of an asset based on the cost to replace it. Principle : High groundwater levels saturate the sand and gravel layers that form the road's sub-base, weakening its structural integrity and load-bearing capacity. This leads to accelerated degradation, such as cracking and potholing, and significantly shortens the effective lifespan of the road pavement (Abdrabo & Hassaan, 2024). Methodology : The core assumption, based on engineering assessments, is that persistent high groundwater levels (defined as a depth of less than 1.5 m) shorten the lifespan of roads by as much as 50%. This means that over a given period, the number of required full replacements of the road surface doubles compared to a business-as-usual (BAU) scenario where groundwater levels are not elevated (Abdrabo & Hassaan, 2024). Damage Cost Calculation : The damage cost (Dc​) is calculated as the additional replacement cost incurred due to the accelerated degradation. The formula is: Dc​=(Rc​×TGw​×Av​)−(Rc​×TBAU​×Av​), where Rc​ is the average replacement cost per square meter of road, TGw​ is the number of replacements required under the high groundwater scenario, TBAU​ is the number of replacements under the BAU scenario, and Av​ is the area of the vulnerable road network (Abdrabo & Hassaan, 2024). 3.3 Data and Assumptions Table 2 Data Sources Data Category Specific Data Type Spatial/Temporal Resolution Description & Application in Analysis Primary Source(s) Spatial & Demographic Coastal management unit boundaries 16 coastal sub-cells along Mediterranean coast Defined spatial units for disaggregated analysis of impacts and valuation Project GIS analysis; National Coastal Zone Management Plan Population distribution Unit-level, 2024 estimates Urban/rural population data for assessing exposure and social vulnerability CAPMAS (2024); Project socioeconomic baseline Land use/land cover (LULC) 30m resolution, 2023 Classification of built-up areas, agriculture, wetlands, barren land for exposure assessment Project remote sensing analysis; European Space Agency Sentinel-2 Economic & Infrastructure Regional GDP composition Governorate-level, 2020/2021 Sectoral contribution (primary, secondary, tertiary) to economic structure analysis MPED (2024); National Accounts Labor force statistics Unit-level, 2021 Employment by sector, unemployment rates for socioeconomic vulnerability assessment CAPMAS (2023); Labor Force Survey Agricultural productivity Crop-specific, per feddan Baseline yields for damage cost calculation of crop and fruit tree losses CAPMAS (2023); Ministry of Agriculture Road network inventory Type (highway/primary/secondary), length Infrastructure exposure assessment and replacement cost valuation National Transport Authority; Project GIS database Infrastructure replacement costs Unit costs (LE/m²) Economic valuation of road damage using replacement cost method Egyptian Ministry of Transportation; Construction cost manuals Hydro-climatic Current groundwater levels Unit-specific depth measurements Baseline conditions for impact assessment and model calibration Project Groundwater Report (2024); National Water Research Center Projected groundwater levels under RCP8.5 2030, 2050, 2080, 2100 scenarios Future exposure scenarios for damage cost projection Hydrological modeling (MODFLOW) forced by SLR projections Sea-level rise projections RCP8.5 scenario, 2100 horizon Climate driver for groundwater rise and saltwater intrusion IPCC AR6; Regional downscaling models Biophysical & Agricultural Crop response parameters Crop-specific waterlogging thresholds Calibration of damage functions linking groundwater depth to yield reduction Literature synthesis (Qureshi et al., 2013; Fawen et al., 2022); Experimental studies Soil characteristics Salinity, permeability, water retention Modifying factor for groundwater-crop productivity relationships National soil surveys; FAO Soil Portal Cultural Heritage Archaeological site inventory Point locations with attributes Exposure assessment of tangible cultural heritage to groundwater threats Supreme Council of Antiquities; Project field surveys (Abdrabo et al., 2023) Heritage vulnerability parameters Material susceptibility to salinity/moisture Qualitative risk assessment of heritage degradation Conservation science literature; ICOMOS guidelines The application of this methodology relies on a rich dataset compiled for Egypt's North Coast. This includes spatially explicit land use/land cover data, a complete GIS inventory of the road network classified by type, baseline socioeconomic data (population, GDP), and agricultural statistics as shown in Figs. 3 , 4 , 5 , 6 , 7 , 8 . Crucially, the analysis is driven by the outputs of a dedicated hydrogeological model that projects groundwater level changes for the years 2030, 2050, 2080, and 2100 under the RCP8.5 high-emissions scenario. A key methodological assumption is the careful avoidance of double counting: any land or infrastructure asset projected to be directly inundated by sea-level rise is excluded from the assessment of damages from rising groundwater, ensuring the two impacts are valued separately (Abdrabo & Hassaan, 2024). This focus on a dynamic, forward-looking climate scenario moves the analysis beyond a static assessment, creating a decision-support tool capable of grappling with the deep uncertainty inherent in long-term infrastructure planning. 4. Application: Valuing Groundwater Changes on Egypt's Mediterranean Coast 4.1 Case Study Context: A Vulnerable Urbanizing Coastline The Mediterranean coast of Egypt serves as a compelling case study for applying the Integrated Hydro-Economic Valuation Framework as shown in Fig. 1 . Extending for approximately 1,000 km, this region is a microcosm of the challenges facing many coastal zones in the Global South: rapid population growth, intense economic activity, and high vulnerability to the impacts of climate change. The region is not a monolith but a diverse mosaic of urban, peri-urban, and rural landscapes, making it an ideal "natural laboratory" to test how the economic impacts of a single physical stressor vary across different development contexts. The study area is administratively divided into 16 coastal sub-units, which can be grouped into three distinct zones: The Nile Delta (Units CU2, CU3, CU4, CU5) : This is the demographic and economic heartland of the region and the nation. It is home to the megacity of Alexandria (CU2-SUB1), with a population of 6.2 million, and a dense network of other cities and agricultural lands. This zone hosts intense industrial, port, and tourism activities and contributes the vast majority of the region's population (94%) and economic output. The total GDP of the coastal units was estimated at L.E. 1.3 trillion in 2020/2021, representing 19% of Egypt's total GDP. The delta's low-lying topography makes it exceptionally vulnerable to both sea-level rise and associated changes in groundwater. The Northwestern Coast (Unit CU1) : Stretching from Alexandria to the Libyan border, this area is characterized by a mix of tourism resorts (e.g., El Alamein), new city developments, and more sparsely populated rural and natural areas. Its economy is less diversified than the delta's, with a strong reliance on tourism and rain-fed agriculture. The Northeastern Coast (Unit CU6) : Located in North Sinai, this zone is more arid and less developed, with key urban centers at El Arish and Rafah. It contains significant protected areas, such as Lake Bardawil. This diversity allows for a nuanced analysis of how vulnerability is shaped not just by physical exposure but also by the concentration of population and economic assets. Table 3 , and Fig. 2 provide a snapshot of the key socioeconomic characteristics of selected representative coastal units, highlighting the stark contrasts within the study area. Table 3 Socioeconomic Profile of Key Coastal Units Coastal Unit Representative Area Population (2024 est.) GDP Contribution (2020/21) Dominant Economic Activities Cultivated Area (2023) CU1-SUB3 Marsa Matruh 286,951 Low Tourism, Resorts, Agriculture 444.0 CU2-SUB1 Alexandria 6,186,059 High (43.6% of total) Industry, Port, Services, Urban 190.9 CU3-SUB1 Behaira (West Delta) 3,179,590 Medium Agriculture, Gas/Petroleum 1102.6 CU4-SUB2 Damietta (East Delta) 1,742,500 High (17.1% of total with CU4) Port, Industry, Agriculture 439.8 4.2 Scenario Definition and Application of the Framework The analysis applies the framework to a single, critical scenario: the impact of rising groundwater levels caused by sea-level rise (SLR) under the Representative Concentration Pathway 8.5 (RCP8.5). This high-emissions scenario, commonly used in climate impact assessments, provides a plausible upper-bound estimate of risk for long-term planning. A dedicated hydrogeological model for the region projected the spatially explicit changes in the depth of the groundwater table for the years 2030, 2050, 2080, and 2100. These projections served as the primary input for Step 1 of the framework. The valuation methodology detailed in Section 3 was then systematically applied. For each of the 16 coastal units, the projected groundwater levels were overlaid with GIS data on agricultural land use and road networks as shown in Fig. 3 . This allowed for the quantification of the vulnerable area (A v ​) for each impact category in each time slice. The dose-response functions for agriculture and the replacement cost calculations for roads were then used to estimate the economic damages in monetary terms (L.E.), completing Steps 2 and 3. The results were kept disaggregated at the coastal sub-unit level, enabling the spatially explicit policy analysis in Step 4. 5. Results The application of the Integrated Hydro-Economic Valuation Framework yields stark quantitative evidence of the significant and escalating economic risks posed by rising groundwater levels along Egypt's Mediterranean coast. The results demonstrate not only the immense scale of the potential damage but also their highly concentrated spatial distribution, revealing a clear nexus of urban vulnerability. 5.1 Aggregate Economic Impacts Aggregating the projected damages across all 16 coastal units reveals a substantial and growing economic liability. The costs, representing a conservative lower-bound estimate focused only on agriculture and roads, escalate dramatically through the 21st century. As shown in Table 4 , the total combined damage costs are projected to increase significantly over time, driven predominantly by the accelerating costs of infrastructure degradation. While agricultural losses are considerable, they are dwarfed by the immense costs associated with the premature failure and required replacement of road networks, particularly in the latter half of the century. This finding highlights a critical shift in the nature of climate-related water risk in urbanizing regions, where the value of built assets at risk can far exceed the value of agricultural production. Table 4 Summary of Projected Economic Damages from Rising Groundwater Levels (Billion L.E.) Impact Category Damage Cost by 2050 Damage Cost by 2080 Damage Cost by 2100 Total Damage (2030–2100) Agricultural Losses 0.08 0.38 0.93 - Road Network Damage 77.26 131.18 212.42 420.86 Total 77.34 131.56 213.35 - Note: Costs for each period (e.g., 2050) represent the cumulative additional cost incurred during the preceding interval (e.g., 2030–2050). The total damage for roads represents the sum of these interval costs. Agricultural losses are annual projections for the specified year. 5.2 Spatial Disaggregation of Impacts: A Story of Urban Concentration The most critical finding of the analysis is the profoundly uneven spatial distribution of these economic risks. The damages are not spread evenly along the coast but are overwhelmingly concentrated in the densely populated, economically vital, and low-lying coastal units of the Nile Delta. The analysis reveals that the coastal units corresponding to the Nile Delta (CU2: Alexandria, CU3: Behaira-Kafr El Sheikh, and CU4: Dakahlia-Damietta) are projected to bear 98.8% of the total damage costs by the year 2100 (Abdrabo & Hassaan, 2024). In contrast, the more arid and less developed units of the Northwestern Coast (CU1) and North Sinai (CU6), along with Port Said (CU5), collectively account for just over 1% of the total damages (Table 5 ). This spatial concentration creates a clear vulnerability nexus where high-value infrastructure and dense populations coincide with acute hydrogeological susceptibility. The results for specific urban units are particularly illustrative: Alexandria (CU2-SUB1) : The projected damage to the road network in this single metropolitan unit is estimated to be L.E. 17.2 billion between 2030–2050, rising to L.E. 25.8 billion for 2050–2080, and a staggering L.E. 129 billion for 2080–2100. The total projected road damage for Alexandria alone amounts to L.E. 172 billion, representing a massive fiscal threat to the governorate (Abdrabo & Hassaan, 2024). Nile Delta Units (CU3 & CU4) : These units, which combine dense agricultural land with significant urban centers and infrastructure, also face enormous costs. For example, the West Burullus unit (CU3-SUB2) is projected to face total road damage costs of L.E. 77.7 billion, while the New Damietta-Ras El Barr unit (CU4-SUB2) faces costs of L.E. 63.6 billion through 2100 (Abdrabo & Hassaan, 2024). Western Desert Units (CU1) : In stark contrast, the damages in the less developed western units are orders of magnitude smaller. The total road damage cost for the entire Marsa Matrouh unit (CU1-SUB3) through 2100 is projected at L.E. 3.0 billion, while the Sallum unit (CU1-SUB1) faces a total cost of only L.E. 0.5 billion (Abdrabo & Hassaan, 2024). This dramatic spatial disparity underscores that while rising groundwater is a regional physical phenomenon, its economic consequences are fundamentally an urban problem, driven by the location and value of man-made assets as shown in Table 5 . Table 5 Spatial Concentration of Projected Total Economic Damages by 2100 Coastal Unit Group Description Total Damage Cost (Billion L.E.) Share of Total Damage (%) CU1 Northwestern Coast 4.96 0.25% CU2 Alexandria 210.02 10.97% CU3 West & Central Delta 984.51 51.43% CU4 East Delta 696.64 36.39% CU5 Port Said 14.71 0.77% CU6 North Sinai 3.58 0.19% Note: Total damage cost is the sum of projected agricultural losses in 2100 and cumulative road damage from 2030–2100. Percentages are derived from these totals. 5.3 Temporal Evolution of Risk The analysis demonstrates a clear temporal escalation of risk. The damage costs projected for the near term (2030–2050) are significant but are substantially lower than those projected for the latter half of the century. For example, the total road damage cost for the Behaira unit (CU3-SUB1) is L.E. 21.3 billion for the 2030–2050 period, but it nearly doubles to L.E. 41.2 billion for the 2050–2080 period (Abdrabo & Hassaan, 2024). This pattern is consistent across all high-risk units, indicating that the most severe economic consequences of climate-induced groundwater changes are a long-term liability. Current development decisions made without consideration for these future costs are effectively locking in massive, unfunded mandates for future generations as shown in Fig. 9 . 6. Discussion The results of the valuation exercise provide more than just a set of numbers; they offer a fundamental reframing of the relationship between groundwater, climate change, and urban development. By translating a complex hydrogeological threat into the universal language of economic cost, the analysis makes the invisible visible, with profound implications for policy and planning. 6.1 Interpreting the Scale of the Economic Threat The multi-billion L.E. damage projections represent a massive, unfunded contingent liability for the Egyptian state and its coastal municipalities. These figures are not abstract environmental costs but foreshadow future budgetary crises. The projected L.E. 172 billion in additional road replacement costs for Alexandria alone is a figure that would overwhelm any municipal capital improvement budget, threatening the city's fiscal solvency and its ability to provide basic services. This analysis fundamentally reframes the "problem" of rising groundwater. It is not merely a technical issue for hydrologists to monitor, but a critical fiscal and governance challenge for mayors, finance ministers, and national planners. By quantifying the "cost of inaction," the valuation provides a powerful economic rationale for proactive investment in adaptation, transforming the discourse from one of environmental protection to one of fiscal prudence and risk management. 6.2 The Contribution of an Integrated Framework This study's primary contribution lies in demonstrating a methodology that overcomes the disciplinary and policy silos identified as a key barrier in the literature (Shrestha et al., 2020; Morris et al., 2000). While previous research has critiqued the fragmentation between water management and urban planning, this paper provides a practical, quantitative tool to force their integration. The Integrated Hydro-Economic Valuation Framework serves as a "boundary object"—a common analytical platform where hydrologists, economists, and urban planners can bring their respective data and models to produce a shared, policy-relevant output. It moves beyond simply stating that a policy gap exists and demonstrates how to bridge it. The spatial concentration of risk revealed in the results illuminates a potential future political economy of adaptation. The overwhelming concentration of projected costs in the Nile Delta provides a rational basis for prioritizing national adaptation funds. However, this could also create political tensions with less-affected regions, highlighting the need for transparent, evidence-based allocation mechanisms that such valuation studies can provide. 6.3 Linking Hydrology, Economics, and Urban Form The findings underscore that economic vulnerability to groundwater changes is a product of the interaction between three distinct systems: the hydrogeological system (physical exposure), the economic system (valuation of assets), and the urban system (the spatial arrangement and density of those assets). The staggering costs for Alexandria are not simply because its groundwater is rising, but because it is a dense, high-value concentration of infrastructure and population located on a susceptible low-lying delta. In contrast, the western coastal units, despite similar physical exposure to SLR, face far lower economic damage due to their different urban form and lower asset density. This confirms the paper's central relevance to the field of urban development: managing hydrogeological risk is inextricably linked to managing urban form. Decisions about where and how to build have direct and quantifiable consequences for future climate-related economic liabilities. 6.4 Limitations and Avenues for Expansion It is crucial to acknowledge the limitations of this valuation, which reinforce the conclusion that the presented figures are conservative, lower-bound estimates. The analysis was intentionally focused on two impact pathways—agriculture and roads—for which robust data and clear dose-response relationships were available. Numerous other significant impacts were not quantified, including: Damage to Buildings and Foundations : Rising groundwater can cause structural damage to buildings through soil saturation, subsidence, and corrosion of foundations, a potentially enormous cost category in dense urban areas (Abdrabo & Hassaan, 2024). Subterranean Infrastructure : The accelerated corrosion and failure of water supply, sanitation, and utility networks buried underground represent another major un-costed liability (Abdrabo & Hassaan, 2024). Public Health Impacts : Higher water tables can lead to dampness in buildings, failure of on-site sanitation systems, and increased incidence of waterborne diseases, carrying significant public health costs (Abdrabo & Hassaan, 2024). Loss of Groundwater-Dependent Ecosystem Services (GDEs) : As noted in the literature review, the degradation of coastal wetlands and other GDEs due to changes in groundwater regimes represents a significant loss of ecological and economic value that remains unquantified (Aziz et al., 2025; Griebler & Avramov, 2015). These un-valued impacts suggest the true economic cost of inaction is likely far greater than estimated here. This highlights the urgent need for future research to expand the scope of valuation to create a more complete picture of the total economic risk. 7. Policy Implications The quantification of economic damages is not an academic exercise; its ultimate purpose is to inform and catalyze more effective policy and planning. The findings from this study have direct and actionable implications for decision-makers at the municipal, regional, and national levels. The valuation results provide the evidence base needed to move from a reactive to a proactive and spatially targeted approach to managing groundwater-related climate risks. 7.1 For Urban and Land-Use Planning The spatially explicit damage projections can serve as a powerful new data layer for urban and regional planners, enabling a shift towards risk-informed development. Risk-Informed Zoning and Development Control : The high-damage zones identified in the analysis (e.g., large parts of Alexandria and the Delta coast) should be designated as special planning areas. Stricter regulations should be applied, potentially prohibiting the construction of new critical infrastructure (hospitals, power plants, major transport links) in the most vulnerable locations and requiring climate-resilience measures for all new developments. Capital Improvement Planning : Municipalities can use the projected infrastructure damage costs to reprioritize their long-term capital improvement plans. The analysis provides a clear economic justification for directing investment towards proactive measures, such as upgrading urban drainage systems, retrofitting roadbeds with more resilient materials, and protecting existing infrastructure in high-risk zones, rather than waiting to incur much higher future repair and replacement costs. Building Codes and Standards : The findings support the case for revising national and municipal building codes to mandate standards for groundwater resilience in vulnerable coastal areas. This could include requirements for elevated foundations, use of water-resistant building materials, and integrated site-level water management systems. 7.2 For Sustainable Groundwater Management The immense "cost of inaction" demonstrated by the valuation provides a compelling economic argument for investing in sustainable groundwater management as a form of risk reduction as shown in Table 6 . Justifying Investment in Monitoring : The study underscores the value of robust data. The economic risks justify significant public investment in comprehensive, real-time groundwater monitoring networks to track changes in water levels and quality, which are essential for validating models and guiding adaptive management (Morris et al., 2000; La Vigna et al., 2022). Promoting Managed Aquifer Recharge (MAR) : The valuation makes a strong business case for proactive interventions like MAR. By investing in systems to capture and recharge aquifers with excess surface water or treated wastewater, authorities can help counteract rising water tables and saltwater intrusion, framing these nature-based solutions as cost-effective investments that avoid far greater future damages (C40 Knowledge Hub, 2025; van der Schyff et al., 2024; Hashemi & Berndtsson, 2022). Integrating Land and Water Governance : The framework itself provides a model for the integrated governance that is critically lacking (Shrestha et al., 2020). The results should be used to mandate joint planning committees between water resource agencies and urban planning authorities, using the shared language of economic risk to align their objectives and policies. 7.3 For National Climate Adaptation and Fiscal Policy At the national level, the valuation provides the macroeconomic data needed to elevate groundwater management on the national agenda. Quantifying National Adaptation Needs : The aggregated damage costs provide a credible, evidence-based figure for Egypt's National Adaptation Plan and its submissions to international climate finance mechanisms like the Green Climate Fund. It demonstrates the scale of funding required to adapt the nation's vulnerable coastal infrastructure. Informing National Fiscal Risk Assessment : The projected damages represent a significant contingent liability for the national government. These quantified risks should be formally incorporated into the Ministry of Finance's long-term fiscal risk registers, ensuring that future budgetary planning accounts for these escalating climate-related costs. Table 6 Policy Recommendations Matrix Valuation Finding Policy Domain Specific Recommendation Lead Agency/Level High projected road damage costs in Alexandria (> L.E. 170 billion). Urban Planning / Infrastructure Revise municipal capital improvement plan to prioritize drainage upgrades and roadbed retrofitting in vulnerable districts. Alexandria Governorate; Ministry of Planning Escalating agricultural losses in the Nile Delta. Water & Agricultural Policy Invest in research and extension services for waterlogging-resistant crop varieties and improved on-farm drainage systems. Ministry of Water Resources; Ministry of Agriculture Extreme concentration of risk in CU2, CU3, CU4. National Climate Adaptation Prioritize allocation of national and international adaptation funds to infrastructure resilience projects in the Nile Delta. Ministry of Environment; Ministry of International Cooperation Widespread infrastructure vulnerability across all coastal units. National Planning / Law Update national building codes for coastal zones to include standards for groundwater-resilient foundations and infrastructure design. Ministry of Housing, Utilities & Urban Communities Entire analysis predicated on modeled projections. Water Resource Management Expand and upgrade the national groundwater monitoring network along the Mediterranean coast for model validation and early warning. Ministry of Water Resources and Irrigation 8. Conclusion This paper began with the premise that groundwater, the invisible foundation of urban resilience, is systematically undervalued in policy and planning, leading to unsustainable and risky development pathways. By developing and applying an Integrated Hydro-Economic Valuation Framework to the case of Egypt's Mediterranean coast, this research has made a significant contribution toward rectifying this omission. The study's primary contribution is a robust, interdisciplinary, and replicable methodology that successfully integrates hydrology, economics, and urban planning to generate decision-relevant evidence. It provides a pragmatic blueprint for how the "invisible" costs of groundwater degradation can be made visible in the economic terms that drive policy. The application of this framework yielded a stark and urgent conclusion: failing to account for climate-induced changes in groundwater carries immense and quantifiable economic costs that threaten the long-term sustainability of coastal urban regions. The multi-billion L.E. damages projected for Egypt's coast are not a distant, abstract environmental problem; they are a looming fiscal crisis that will manifest in failing infrastructure, reduced economic productivity, and constrained municipal budgets. The highly concentrated nature of this risk in the urbanized Nile Delta underscores that groundwater vulnerability is fundamentally an urban development challenge, demanding solutions rooted in spatial planning, infrastructure management, and governance reform. The ultimate takeaway is that sustainable urban development and sustainable groundwater management are not separate objectives but two sides of the same coin. The long-term viability of our cities depends on recognizing and managing the hydrogeological systems upon which they are built. Ignoring this invisible foundation will lead to staggering and entirely foreseeable economic and social costs. This research opens several critical pathways for future inquiry. First, the scope of valuation must be expanded. Future work should aim to incorporate the significant non-market values and ecosystem services—such as damage to building foundations, public health impacts, and the degradation of GDEs—that were beyond the scope of this study, in order to capture the total economic cost more comprehensively. Second, the framework's versatility should be tested by applying it to different urban and hydrogeological contexts, such as inland cities facing groundwater depletion and land subsidence, to broaden its applicability. Finally, future research must integrate a social equity lens, analyzing the distributional impacts of both groundwater changes and proposed policy responses to ensure that adaptation measures do not disproportionately burden the most vulnerable populations within cities. By pursuing these avenues, the research community can continue to build the evidence base needed to recalibrate urban development for a truly resilient and water-secure future. Declarations Data Availability Statement: The data sets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request. Funding Declaration: No funding was received for conducting this study. Clinical Trial Number: Not applicable. Consent to Participate Declaration: Not applicable. Consent to Publish Declaration: Not applicable. Ethics Declaration: Not applicable. 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08:39:21","extension":"xml","order_by":21,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":106219,"visible":true,"origin":"","legend":"","description":"","filename":"ec6d36fdf34d447bbab382c97cd9941f1structuring.xml","url":"https://assets-eu.researchsquare.com/files/rs-7846108/v1/8461bba97476f8b74b926d07.xml"},{"id":96917007,"identity":"f9556ba9-09ab-4327-b461-4d1c707f632b","added_by":"auto","created_at":"2025-11-27 14:09:08","extension":"html","order_by":22,"title":"","display":"","copyAsset":false,"role":"acdc-reference","size":114946,"visible":true,"origin":"","legend":"","description":"","filename":"earlyproof.html","url":"https://assets-eu.researchsquare.com/files/rs-7846108/v1/c27c8906e4153889e4bfcb4d.html"},{"id":96801530,"identity":"dd1890f5-d470-4b4c-8440-83289ca2a2a5","added_by":"auto","created_at":"2025-11-26 08:39:20","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":315712,"visible":true,"origin":"","legend":"\u003cp\u003eThe coastal zone units in the study area\u003c/p\u003e","description":"","filename":"image1.png","url":"https://assets-eu.researchsquare.com/files/rs-7846108/v1/31030bd6a3a2259c6c728b71.png"},{"id":96801525,"identity":"3ace559d-5b65-4993-bc3c-1664c2ff6df8","added_by":"auto","created_at":"2025-11-26 08:39:19","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":41163,"visible":true,"origin":"","legend":"\u003cp\u003eThe relative distribution of population among different coastal units in the Mediterranean coastal zone in Egypt\u003c/p\u003e","description":"","filename":"image2.png","url":"https://assets-eu.researchsquare.com/files/rs-7846108/v1/5d6cd200e55beb3f27a592a5.png"},{"id":96918127,"identity":"2f59162c-a254-499f-8250-db0fdd251dc4","added_by":"auto","created_at":"2025-11-27 14:11:11","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":16381,"visible":true,"origin":"","legend":"\u003cp\u003eLand use/Land cover in the Mediterranean coastal zone in Egypt\u003c/p\u003e","description":"","filename":"image3.png","url":"https://assets-eu.researchsquare.com/files/rs-7846108/v1/24883d8a80f5450d6196c2f6.png"},{"id":96918164,"identity":"9de2fba1-5276-4d7f-978c-b863aaf098dd","added_by":"auto","created_at":"2025-11-27 14:11:14","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":54831,"visible":true,"origin":"","legend":"\u003cp\u003eLand use/Land cover in coastal unit (1)\u003c/p\u003e","description":"","filename":"image4.png","url":"https://assets-eu.researchsquare.com/files/rs-7846108/v1/b3b991822c67087ed3abda05.png"},{"id":96801546,"identity":"4d0e637c-6cbf-4254-abcc-b6f0ce24d03f","added_by":"auto","created_at":"2025-11-26 08:39:21","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":132896,"visible":true,"origin":"","legend":"\u003cp\u003eLand use/Land cover in coastal units (2), (3), (4), and (5)\u003c/p\u003e","description":"","filename":"image5.png","url":"https://assets-eu.researchsquare.com/files/rs-7846108/v1/8c322c6ee8bbd894c989a775.png"},{"id":96801548,"identity":"c6c0a8c4-cc7d-4958-8ad0-dd596f2b8e51","added_by":"auto","created_at":"2025-11-26 08:39:21","extension":"png","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":71916,"visible":true,"origin":"","legend":"\u003cp\u003eLand use/Land cover in coastal unit (6)\u003c/p\u003e","description":"","filename":"image6.png","url":"https://assets-eu.researchsquare.com/files/rs-7846108/v1/897586f45cdd0097ec94c8e1.png"},{"id":96801534,"identity":"d215207f-d1b4-48a5-8bce-582bbf820626","added_by":"auto","created_at":"2025-11-26 08:39:20","extension":"png","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":38396,"visible":true,"origin":"","legend":"\u003cp\u003eLand use/Land cover in the Mediterranean coastal units in Egypt\u003c/p\u003e","description":"","filename":"image7.png","url":"https://assets-eu.researchsquare.com/files/rs-7846108/v1/71beb06a03676c5ec92d7472.png"},{"id":96801526,"identity":"14662b93-a2e2-4463-911f-cd6194eb7484","added_by":"auto","created_at":"2025-11-26 08:39:19","extension":"png","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":103835,"visible":true,"origin":"","legend":"\u003cp\u003eRelative \u0026nbsp;\u0026nbsp;distribution of labor force in the Mediterranean coastal units\u003c/p\u003e","description":"","filename":"image8.png","url":"https://assets-eu.researchsquare.com/files/rs-7846108/v1/90572344c28b626313fffea7.png"},{"id":96801551,"identity":"a32bbd8a-1067-41ae-8811-ffec32366d7b","added_by":"auto","created_at":"2025-11-26 08:39:21","extension":"png","order_by":9,"title":"Figure 9","display":"","copyAsset":false,"role":"figure","size":19730,"visible":true,"origin":"","legend":"\u003cp\u003eRelative distribution of damage cost associated with high levels of groundwater per coastal unit by 2100\u003c/p\u003e","description":"","filename":"image9.png","url":"https://assets-eu.researchsquare.com/files/rs-7846108/v1/287390c9ff344453c3f09b2e.png"},{"id":96922845,"identity":"f466088a-b718-44e9-8ec0-d76ee08f4e9d","added_by":"auto","created_at":"2025-11-27 14:20:02","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2732438,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7846108/v1/adfdb473-027c-4f3d-877a-3989686c9e5d.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Valuing Groundwater Impacts for Sustainable Urban Planning in Coastal Cities","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eGroundwater, accounting for approximately 99% of all liquid freshwater on Earth, is a foundational resource for global human development and urban sustainability (IOM, 2025). It supplies nearly half of all drinking water worldwide, 43% of water for irrigation, and a substantial portion for industrial processes, supporting the livelihoods of billions (The World Bank, 2023; Jasechko \u0026amp; Perrone, 2018). In an era of increasing climate variability, the vast storage capacity of aquifers provides a unique natural buffer against shocks such as drought and unpredictable surface water flows (IOM, 2025; IAH, 2019). This buffering capacity has led to groundwater being described as \"nature's insurance,\" a critical asset for enhancing the climate resilience of cities and protecting economies from water-related shocks (The World Bank, 2023; IAH, 2019).\u003c/p\u003e\u003cp\u003eDespite this vital role, a profound paradox lies at the heart of urban development: the more cities grow, the more they depend on this invisible resource, yet the very processes of urbanization\u0026mdash;such as surface sealing from construction, increased abstraction, and pollution from industrial and domestic waste\u0026mdash;degrade and deplete the groundwater systems beneath them (USGS, 2025; Singh, 2012; Carre\u0026oacute;n-Freyre et al., 2022). This is particularly acute in the rapidly urbanizing Global South, where institutional and financial capacities to manage this interplay are often limited (Shrestha et al., 2020; Foster et al., 2002). Groundwater is frequently characterized by open access and is often poorly understood, leading to it being systematically undervalued and mismanaged in policy and public discourse (IOM, 2025; Foster, 2022; UN-Water, 2022).\u003c/p\u003e\u003cp\u003eThis undervaluation is not merely a conceptual issue; it has tangible and severe consequences for urban planning. The \"invisibility\" of groundwater is as much economic and political as it is physical. Because its services are not traded in conventional markets, groundwater is often assigned a default value of zero in the cost-benefit analyses that drive urban infrastructure investment and land-use zoning decisions (Tsur, 2000). When a city planner evaluates a new coastal development, the long-term costs of saltwater intrusion, land subsidence from over-extraction, or, as this paper explores, damage from rising groundwater levels, are typically absent from the balance sheet. This absence of a clear financial signal encourages maladaptive development patterns, exposing populations and high-value economic assets to foreseeable but un-costed risks. Furthermore, a fundamental mismatch exists between the temporal scales of urban planning, which often operates on 5- to 10-year cycles, and the slow-onset nature of groundwater system changes, which can unfold over decades or centuries (IAH, 2019).\u003c/p\u003e\u003cp\u003eWhile a growing body of literature critiques the policy disconnect between water resource management and urban planning, particularly in the Global South (Shrestha et al., 2020; Gardu\u0026ntilde;o \u0026amp; Foster, 2011; Morris et al., 2000), it often lacks the quantitative, decision-relevant metrics needed to bridge this gap. This paper addresses this critical knowledge gap by developing and applying an \u003cb\u003eIntegrated Hydro-Economic Valuation Framework\u003c/b\u003e. The novelty of this framework lies in its ability to translate complex, long-term hydrogeological changes into tangible economic costs that are spatially explicit and directly relevant to urban planners, finance ministries, and infrastructure managers. By monetizing the physical damage, the framework makes the \"invisible\" costs of inaction visible, providing a common language\u0026mdash;money\u0026mdash;to facilitate dialogue and integration across traditionally siloed policy domains.\u003c/p\u003e\u003cp\u003eThis research aims to answer the following key questions:\u003c/p\u003e\u003cp\u003e\u003col\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eHow can the economic impacts of climate-induced groundwater changes on critical urban and peri-urban systems be systematically valued?\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eWhat is the potential scale and spatial distribution of these economic impacts in a representative, rapidly urbanizing coastal region under a high-emissions climate scenario?\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003eHow can these valuation outcomes be translated into actionable urban planning, sustainable water management, and climate adaptation policies?\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003c/ol\u003e\u003c/p\u003e\u003cp\u003eTo answer these questions, this paper first reviews the literature on groundwater valuation and its intersection with urban policy. It then details the Integrated Hydro-Economic Valuation Framework and its specific methodological application. Subsequently, it applies this framework to a comprehensive case study of Egypt's Mediterranean coast, a region characterized by high population density, significant economic assets, and acute vulnerability to climate change-induced sea-level rise and associated groundwater impacts. The results quantify the projected economic damage to agriculture and road networks through 2100. The paper concludes by discussing the profound implications of these findings for urban planning and policy, not only in Egypt but for vulnerable coastal cities worldwide.\u003c/p\u003e"},{"header":"2. Literature Review","content":"\u003cp\u003eUnderstanding the economic impacts of groundwater changes on urban systems requires an interdisciplinary approach that bridges environmental economics, hydrology, and urban policy. However, the literature in these fields has often evolved in parallel, creating significant knowledge gaps. This review critically examines three key areas: the established methods for water resource valuation, the emerging frontier of valuing groundwater's ecological role, and the well-documented governance failures that prevent valuation from influencing urban policy in the Global South.\u003c/p\u003e\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003e2.1 The Economic Valuation of Water Resources\u003c/h2\u003e\u003cp\u003eThe economic valuation of water seeks to quantify its contribution to human welfare in monetary terms, providing a basis for efficient allocation and management (Ghosh \u0026amp; Bandyopadhyay, 2009; FAO, 2004). The guiding conceptual model is Total Economic Value (TEV), which categorizes value into several components. \u003cb\u003eUse values\u003c/b\u003e derive from the direct or indirect use of the resource, such as water for irrigation (direct use) or the flood control functions of a wetland (indirect use). \u003cb\u003eNon-use values\u003c/b\u003e capture the value people hold for a resource independent of their own use, including bequest value (for future generations) and existence value (the value of knowing a resource exists) (Arthur D. Little, 2025; FAO, 2004).\u003c/p\u003e\u003cp\u003eTo estimate these values, economists have developed three main families of methods (Abdrabo \u0026amp; Hassaan, 2024; IWRM Toolbox, 2025; EPA, 2018).\u003c/p\u003e\u003cp\u003e\u003col\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eMarket-Based Approaches\u003c/b\u003e: These methods use market data or engineered costs to infer value. The \u003cb\u003edose-response function\u003c/b\u003e links a change in an environmental variable (e.g., water level) to a change in a marketed output (e.g., crop yield), valuing the impact at market prices. The \u003cb\u003ereplacement cost\u003c/b\u003e or \u003cb\u003eavoided cost\u003c/b\u003e method values an environmental service based on the cost of replacing it with man-made technology (e.g., valuing water purification by the cost of a treatment plant) (EPA, 2018; Zhang et al., 2020). These methods are often favored for their reliance on observable data but can only capture a subset of total value.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eRevealed Preference Methods\u003c/b\u003e: These techniques infer value from observed behavior in related markets. \u003cb\u003eHedonic pricing\u003c/b\u003e, for instance, analyzes property values to determine how environmental amenities, such as proximity to a clean water body, are capitalized into housing prices (IWRM Toolbox, 2025; Business Case Studies, 2025). The \u003cb\u003etravel cost method\u003c/b\u003e estimates the recreational value of a site by analyzing how much people are willing to spend to visit it (EPA, 2018). These methods are powerful for valuing specific amenities but are limited to contexts where such related market behavior can be observed.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eStated Preference Methods\u003c/b\u003e: When no market behavior exists to reveal values (especially for non-use values), these methods use carefully constructed surveys to create a hypothetical market. The most prominent is the \u003cb\u003eContingent Valuation Method (CVM)\u003c/b\u003e, which directly asks individuals their willingness-to-pay (WTP) for an environmental improvement or willingness-to-accept (WTA) compensation for a loss (Ghosh \u0026amp; Bandyopadhyay, 2009; Loomis, 2000). While CVM is theoretically capable of capturing TEV, it is subject to numerous biases, including hypothetical bias (what people say they would pay differs from what they actually would), strategic behavior, and embedding effects, where the value stated is insensitive to the scope of the good being valued (Duberstein, 2004; Venkatachalam, 2004; Whittington, 1998). These challenges are particularly pronounced in developing country contexts, where unfamiliarity with hypothetical markets and institutional mistrust can complicate survey administration (Whittington, 1998). The choice of valuation method is therefore not merely technical but strategic; complex, data-intensive methods like CVM may be impractical in data-scarce regions, inadvertently perpetuating the very problem of undervaluation they seek to solve (Morris et al., 2000; Duberstein, 2004; MacDonald et al., 2017).\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003c/ol\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec4\" class=\"Section2\"\u003e\u003ch2\u003e2.2 The Frontier: Valuing Groundwater-Dependent Ecosystem Services (GDEs)\u003c/h2\u003e\u003cp\u003eA significant gap in the valuation literature concerns the ecological role of groundwater. Aquifers are not merely underground reservoirs; they are ecosystems that provide critical supporting and regulating services, such as water purification, nutrient cycling, and sustaining the baseflow of rivers and the health of wetlands and other groundwater-dependent ecosystems (GDEs) (Aziz et al., 2025; Griebler \u0026amp; Avramov, 2015). These services are foundational to the health of broader terrestrial and aquatic ecosystems and provide immense, albeit largely unquantified, economic value (Aziz et al., 2025; Anonymous, 2024).\u003c/p\u003e\u003cp\u003eThe scientific and economic challenges in this area are substantial. Quantifying the link between a change in a groundwater regime and the functioning of a dependent ecosystem requires sophisticated, integrated hydrogeological models that are rarely available (Aziz et al., 2025). Consequently, large-scale monetary estimates for GDEs are largely absent from major ecosystem service valuation studies, representing a critical assessment gap (Griebler \u0026amp; Avramov, 2015). While frameworks for GDE valuation have been proposed, they often remain conceptual or are applied at a very local scale (Eamus et al., 2008). This paper acknowledges this frontier by focusing on the more tractable, direct-use values associated with agriculture and infrastructure, framing its findings as a conservative, lower-bound estimate of the total economic costs of groundwater changes. The un-valued loss of GDEs remains a critical area for future interdisciplinary research.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec5\" class=\"Section2\"\u003e\u003ch2\u003e2.3 The Governance Gap: Policy Fragmentation in the Urban Global South\u003c/h2\u003e\u003cp\u003eEven where valuation studies are conducted, their impact on policy is often muted by deep-seated governance challenges, particularly in the rapidly urbanizing Global South. A consistent theme in the literature is the profound disconnect between water resource management and urban land-use planning (Shrestha et al., 2020; Morris et al., 2000; Water in the West, 2025). Urban, water, and climate policies are typically formulated and implemented in institutional silos, with insufficient focus on urban water security and a lack of effective interlinkages between sectors (Shrestha et al., 2020; Van der Walt et al., 2023; Wolf et al., 2007).\u003c/p\u003e\u003cp\u003eThis policy fragmentation is a direct cause of the undervaluation problem. When the Ministry of Urban Planning and a Ministry of Water Resources operate independently, the costs incurred by one sector (e.g., long-term aquifer depletion or contamination) are not factored into the benefits pursued by the other (e.g., short-term economic growth from urban expansion). This leads to what has been termed a \"silent revolution\" of unplanned and unmanaged groundwater exploitation that accompanies urbanization, creating long-term vulnerabilities that are not reflected in current policy priorities (Foster et al., 2002; Gardu\u0026ntilde;o \u0026amp; Foster, 2011). Key constraints identified across numerous studies include a lack of hydrogeological data, weak institutional capacity, fragmented legal frameworks, and a general failure to integrate scientific understanding of groundwater systems into spatial planning and development control (Shrestha et al., 2020; Morris et al., 2000; Minea \u0026amp; Călin, 2022; La Vigna et al., 2022). The challenge, therefore, is not only to value groundwater but to embed that valuation within governance structures in a way that forces integrated, cross-sectoral decision-making.\u003c/p\u003e\u003c/div\u003e"},{"header":"3. Conceptual Framework and Methodology: An Integrated Hydro-Economic Approach","content":"\u003cp\u003eTo address the policy and valuation gaps identified in the literature, this paper proposes and applies an Integrated Hydro-Economic Valuation Framework. This framework provides a structured, replicable process for translating physical changes in groundwater systems into spatially explicit economic metrics that can directly inform urban planning and climate adaptation policy. Its strength lies in its modularity and its pragmatic focus on methods that are applicable in data-constrained environments, common in the Global South.\u003c/p\u003e\u003cdiv id=\"Sec7\" class=\"Section2\"\u003e\u003ch2\u003e3.1 The Integrated Hydro-Economic Valuation Framework\u003c/h2\u003e\u003cp\u003eThe framework consists of a four-step, interdisciplinary process designed to bridge hydrology, economics, and urban policy (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e).\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eStep 1: Hydrogeological Scenario Analysis.\u003c/b\u003e The process begins with a clear definition of the physical stressor on the groundwater system. This requires input from hydrogeological models that project changes in key groundwater parameters (e.g., water table depth, salinity) over a defined time horizon and under specific drivers, such as climate change scenarios (e.g., RCPs), land-use change, or extraction patterns.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eStep 2: Impact Pathway Identification.\u003c/b\u003e This step maps the causal chain from the physical hydrogeological change to specific, tangible impacts on human systems. It requires identifying the key urban and peri-urban assets and economic activities that are sensitive to groundwater conditions. Examples include waterlogging of agricultural lands, saturation of road sub-bases, corrosion of subterranean infrastructure, damage to building foundations, and degradation of GDEs.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eStep 3: Economic Quantification.\u003c/b\u003e This step applies appropriate economic valuation techniques to monetize the physical impacts identified in Step 2. The choice of method depends on the impact pathway and data availability. The framework prioritizes pragmatic, data-driven methods such as dose-response functions and replacement cost analysis, which are more readily applicable in many developing country contexts than complex stated preference surveys.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eStep 4: Spatially Explicit Policy Analysis.\u003c/b\u003e The final step involves disaggregating the total economic costs and analyzing their distribution across relevant administrative and planning units (e.g., municipalities, coastal management zones). This spatial analysis is crucial for identifying hotspots of vulnerability, prioritizing investments, and tailoring policy interventions to the specific risk profiles of different urban and rural areas.\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eThe Integrated Hydro-Economic Valuation Framework\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eStep\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eDescription\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eKey Inputs\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eKey Outputs\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003e1. Hydrogeological Scenario Analysis\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eDefine and model the physical change in the groundwater system over time.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eClimate projections (e.g., SLR), land use models, extraction data, hydrogeological models.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSpatially explicit maps of projected changes in groundwater levels, quality, etc.\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003e2. Impact Pathway Identification\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eLink physical groundwater changes to specific impacts on urban assets and economic sectors.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eAsset inventories (infrastructure, buildings), land use maps, agricultural data.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eA matrix of assets at risk and the mechanisms of impact (e.g., waterlogging, subsidence).\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003e3. Economic Quantification\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eApply valuation methods to monetize the physical impacts in a common unit (currency).\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMarket prices (crops, construction), engineering cost data, dose-response functions.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMonetary estimates of damage costs over time (e.g., agricultural losses, infrastructure repair costs).\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003e4. Spatially Explicit Policy Analysis\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAnalyze the spatial distribution of economic costs to inform targeted policy and planning.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eGIS data of administrative boundaries, valuation results from Step 3.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eVulnerability maps, risk-based zoning recommendations, prioritized investment plans.\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e\u003ch2\u003e3.2 Valuation Methodology for the Case Study\u003c/h2\u003e\u003cp\u003eThe application of this framework to Egypt's North Coast utilizes two primary valuation methods, as detailed in the technical assessment for the region (Abdrabo \u0026amp; Hassaan, 2024). These methods were selected for their robustness and reliance on available engineering and economic data as shown in Table \u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e\u003cdiv id=\"Sec9\" class=\"Section3\"\u003e\u003ch2\u003e3.2.1 Valuing Agricultural Impacts (Dose-Response Function)\u003c/h2\u003e\u003cp\u003eThe impact of rising groundwater levels on agricultural productivity is valued using a dose-response or production function approach. This method establishes a quantitative relationship between the environmental stressor (high groundwater table) and the economic output (crop yield).\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003ePrinciple\u003c/b\u003e: Optimal agricultural yield requires groundwater to be at a sufficient depth below the root zone. As the water table rises, it leads to soil saturation, poor aeration, root damage, and the growth of fungi, all of which reduce crop productivity and can ultimately cause plant death (Abdrabo \u0026amp; Hassaan, 2024).\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eMethodology\u003c/b\u003e: The relationship between groundwater depth and yield reduction was calibrated using segmented polynomial regression based on data from various literature sources. This resulted in specific functions for two main agricultural categories: field crops and fruit trees (Abdrabo \u0026amp; Hassaan, 2024).\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eFor crops, the reduction rate in yield (y) as a function of groundwater level (x) is given by y\u0026thinsp;=\u0026thinsp;6.6233x3\u0026thinsp;\u0026minus;\u0026thinsp;44.59x2\u0026thinsp;+\u0026thinsp;107.67x\u0026thinsp;+\u0026thinsp;0.4618\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eFor fruit trees, the function is: y\u0026thinsp;=\u0026thinsp;7.42x3\u0026thinsp;\u0026minus;\u0026thinsp;51.481x2\u0026thinsp;+\u0026thinsp;119.81x\u0026thinsp;\u0026minus;\u0026thinsp;0.7439\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003cp\u003e\u003cb\u003eDamage Cost Calculation\u003c/b\u003e: The total damage cost to agriculture (Dc​) is then calculated by multiplying the projected yield loss by the value of the agricultural output in the vulnerable area. The formula applied is: Dc​=Pp​\u0026times;Av​\u0026times;100y​, where Pp​ is the average productivity per unit area of cultivated land (projected based on GDP growth), Av​ is the vulnerable cultivated area exposed to a given groundwater level, and y is the percentage reduction in yield derived from the functions above (Abdrabo \u0026amp; Hassaan, 2024).\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec10\" class=\"Section3\"\u003e\u003ch2\u003e3.2.2 Valuing Infrastructure Impacts (Replacement Cost Method)\u003c/h2\u003e\u003cp\u003eThe damage to road networks is valued using the replacement cost method, which estimates the value of an asset based on the cost to replace it.\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003ePrinciple\u003c/b\u003e: High groundwater levels saturate the sand and gravel layers that form the road's sub-base, weakening its structural integrity and load-bearing capacity. This leads to accelerated degradation, such as cracking and potholing, and significantly shortens the effective lifespan of the road pavement (Abdrabo \u0026amp; Hassaan, 2024).\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eMethodology\u003c/b\u003e: The core assumption, based on engineering assessments, is that persistent high groundwater levels (defined as a depth of less than 1.5 m) shorten the lifespan of roads by as much as 50%. This means that over a given period, the number of required full replacements of the road surface doubles compared to a business-as-usual (BAU) scenario where groundwater levels are not elevated (Abdrabo \u0026amp; Hassaan, 2024).\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eDamage Cost Calculation\u003c/b\u003e: The damage cost (Dc​) is calculated as the additional replacement cost incurred due to the accelerated degradation. The formula is: Dc​=(Rc​\u0026times;TGw​\u0026times;Av​)\u0026minus;(Rc​\u0026times;TBAU​\u0026times;Av​), where Rc​ is the average replacement cost per square meter of road, TGw​ is the number of replacements required under the high groundwater scenario, TBAU​ is the number of replacements under the BAU scenario, and Av​ is the area of the vulnerable road network (Abdrabo \u0026amp; Hassaan, 2024).\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003c/div\u003e\u003c/div\u003e\u003cdiv id=\"Sec11\" class=\"Section2\"\u003e\u003ch2\u003e3.3 Data and Assumptions\u003c/h2\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eData Sources\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eData Category\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSpecific Data Type\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eSpatial/Temporal Resolution\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eDescription \u0026amp; Application in Analysis\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003ePrimary Source(s)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eSpatial \u0026amp; Demographic\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eCoastal management unit boundaries\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e16 coastal sub-cells along Mediterranean coast\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eDefined spatial units for disaggregated analysis of impacts and valuation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eProject GIS analysis; National Coastal Zone Management Plan\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePopulation distribution\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eUnit-level, 2024 estimates\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eUrban/rural population data for assessing exposure and social vulnerability\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eCAPMAS (2024); Project socioeconomic baseline\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eLand use/land cover (LULC)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e30m resolution, 2023\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eClassification of built-up areas, agriculture, wetlands, barren land for exposure assessment\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eProject remote sensing analysis; European Space Agency Sentinel-2\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"4\" rowspan=\"5\"\u003e\u003cp\u003eEconomic \u0026amp; Infrastructure\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eRegional GDP composition\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eGovernorate-level, 2020/2021\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eSectoral contribution (primary, secondary, tertiary) to economic structure analysis\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eMPED (2024); National Accounts\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eLabor force statistics\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eUnit-level, 2021\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eEmployment by sector, unemployment rates for socioeconomic vulnerability assessment\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eCAPMAS (2023); Labor Force Survey\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAgricultural productivity\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eCrop-specific, per feddan\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eBaseline yields for damage cost calculation of crop and fruit tree losses\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eCAPMAS (2023); Ministry of Agriculture\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eRoad network inventory\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eType (highway/primary/secondary), length\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eInfrastructure exposure assessment and replacement cost valuation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eNational Transport Authority; Project GIS database\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eInfrastructure replacement costs\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eUnit costs (LE/m\u0026sup2;)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eEconomic valuation of road damage using replacement cost method\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eEgyptian Ministry of Transportation; Construction cost manuals\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"2\" rowspan=\"3\"\u003e\u003cp\u003eHydro-climatic\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eCurrent groundwater levels\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eUnit-specific depth measurements\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eBaseline conditions for impact assessment and model calibration\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eProject Groundwater Report (2024); National Water Research Center\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eProjected groundwater levels under RCP8.5\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003e2030, 2050, 2080, 2100 scenarios\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eFuture exposure scenarios for damage cost projection\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eHydrological modeling (MODFLOW) forced by SLR projections\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSea-level rise projections\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eRCP8.5 scenario, 2100 horizon\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eClimate driver for groundwater rise and saltwater intrusion\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eIPCC AR6; Regional downscaling models\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eBiophysical \u0026amp; Agricultural\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eCrop response parameters\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eCrop-specific waterlogging thresholds\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eCalibration of damage functions linking groundwater depth to yield reduction\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eLiterature synthesis (Qureshi et al., 2013; Fawen et al., 2022); Experimental studies\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eSoil characteristics\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eSalinity, permeability, water retention\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eModifying factor for groundwater-crop productivity relationships\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eNational soil surveys; FAO Soil Portal\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e\u003cp\u003eCultural Heritage\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eArchaeological site inventory\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003ePoint locations with attributes\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eExposure assessment of tangible cultural heritage to groundwater threats\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eSupreme Council of Antiquities; Project field surveys (Abdrabo et al., 2023)\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eHeritage vulnerability parameters\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eMaterial susceptibility to salinity/moisture\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eQualitative risk assessment of heritage degradation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eConservation science literature; ICOMOS guidelines\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003eThe application of this methodology relies on a rich dataset compiled for Egypt's North Coast. This includes spatially explicit land use/land cover data, a complete GIS inventory of the road network classified by type, baseline socioeconomic data (population, GDP), and agricultural statistics as shown in Figs.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e,\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e,\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e,\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e,\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e,\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e. Crucially, the analysis is driven by the outputs of a dedicated hydrogeological model that projects groundwater level changes for the years 2030, 2050, 2080, and 2100 under the RCP8.5 high-emissions scenario. A key methodological assumption is the careful avoidance of double counting: any land or infrastructure asset projected to be directly inundated by sea-level rise is excluded from the assessment of damages from rising groundwater, ensuring the two impacts are valued separately (Abdrabo \u0026amp; Hassaan, 2024). This focus on a dynamic, forward-looking climate scenario moves the analysis beyond a static assessment, creating a decision-support tool capable of grappling with the deep uncertainty inherent in long-term infrastructure planning.\u003c/p\u003e\u003c/div\u003e"},{"header":"4. Application: Valuing Groundwater Changes on Egypt's Mediterranean Coast","content":"\u003cdiv id=\"Sec13\" class=\"Section2\"\u003e\u003ch2\u003e4.1 Case Study Context: A Vulnerable Urbanizing Coastline\u003c/h2\u003e\u003cp\u003eThe Mediterranean coast of Egypt serves as a compelling case study for applying the Integrated Hydro-Economic Valuation Framework as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. Extending for approximately 1,000 km, this region is a microcosm of the challenges facing many coastal zones in the Global South: rapid population growth, intense economic activity, and high vulnerability to the impacts of climate change. The region is not a monolith but a diverse mosaic of urban, peri-urban, and rural landscapes, making it an ideal \"natural laboratory\" to test how the economic impacts of a single physical stressor vary across different development contexts.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003eThe study area is administratively divided into 16 coastal sub-units, which can be grouped into three distinct zones:\u003c/p\u003e\u003cp\u003e\u003col\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eThe Nile Delta (Units CU2, CU3, CU4, CU5)\u003c/b\u003e: This is the demographic and economic heartland of the region and the nation. It is home to the megacity of Alexandria (CU2-SUB1), with a population of 6.2\u0026nbsp;million, and a dense network of other cities and agricultural lands. This zone hosts intense industrial, port, and tourism activities and contributes the vast majority of the region's population (94%) and economic output. The total GDP of the coastal units was estimated at L.E. 1.3 trillion in 2020/2021, representing 19% of Egypt's total GDP. The delta's low-lying topography makes it exceptionally vulnerable to both sea-level rise and associated changes in groundwater.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eThe Northwestern Coast (Unit CU1)\u003c/b\u003e: Stretching from Alexandria to the Libyan border, this area is characterized by a mix of tourism resorts (e.g., El Alamein), new city developments, and more sparsely populated rural and natural areas. Its economy is less diversified than the delta's, with a strong reliance on tourism and rain-fed agriculture.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003cspan\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eThe Northeastern Coast (Unit CU6)\u003c/b\u003e: Located in North Sinai, this zone is more arid and less developed, with key urban centers at El Arish and Rafah. It contains significant protected areas, such as Lake Bardawil.\u003c/p\u003e\u003c/li\u003e\u003c/span\u003e\u003c/ol\u003e\u003c/p\u003e\u003cp\u003eThis diversity allows for a nuanced analysis of how vulnerability is shaped not just by physical exposure but also by the concentration of population and economic assets. Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, and Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e provide a snapshot of the key socioeconomic characteristics of selected representative coastal units, highlighting the stark contrasts within the study area.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eSocioeconomic Profile of Key Coastal Units\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"6\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCoastal Unit\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eRepresentative Area\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003ePopulation (2024 est.)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eGDP Contribution (2020/21)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eDominant Economic Activities\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c6\"\u003e\u003cp\u003eCultivated Area (2023)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCU1-SUB3\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eMarsa Matruh\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e286,951\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eLow\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eTourism, Resorts, Agriculture\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e444.0\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCU2-SUB1\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAlexandria\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e6,186,059\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHigh (43.6% of total)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eIndustry, Port, Services, Urban\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e190.9\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCU3-SUB1\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eBehaira (West Delta)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e3,179,590\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMedium\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003eAgriculture, Gas/Petroleum\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e1102.6\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCU4-SUB2\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eDamietta (East Delta)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e1,742,500\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eHigh (17.1% of total with CU4)\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003ePort, Industry, Agriculture\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c6\"\u003e\u003cp\u003e439.8\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e\u003ch2\u003e4.2 Scenario Definition and Application of the Framework\u003c/h2\u003e\u003cp\u003eThe analysis applies the framework to a single, critical scenario: the impact of rising groundwater levels caused by sea-level rise (SLR) under the Representative Concentration Pathway 8.5 (RCP8.5). This high-emissions scenario, commonly used in climate impact assessments, provides a plausible upper-bound estimate of risk for long-term planning. A dedicated hydrogeological model for the region projected the spatially explicit changes in the depth of the groundwater table for the years 2030, 2050, 2080, and 2100. These projections served as the primary input for Step 1 of the framework.\u003c/p\u003e\u003cp\u003eThe valuation methodology detailed in Section \u003cspan refid=\"Sec6\" class=\"InternalRef\"\u003e3\u003c/span\u003e was then systematically applied. For each of the 16 coastal units, the projected groundwater levels were overlaid with GIS data on agricultural land use and road networks as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e. This allowed for the quantification of the vulnerable area (A\u003csub\u003ev\u003c/sub\u003e​) for each impact category in each time slice. The dose-response functions for agriculture and the replacement cost calculations for roads were then used to estimate the economic damages in monetary terms (L.E.), completing Steps 2 and 3. The results were kept disaggregated at the coastal sub-unit level, enabling the spatially explicit policy analysis in Step 4.\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003c/div\u003e"},{"header":"5. Results","content":"\u003cp\u003eThe application of the Integrated Hydro-Economic Valuation Framework yields stark quantitative evidence of the significant and escalating economic risks posed by rising groundwater levels along Egypt's Mediterranean coast. The results demonstrate not only the immense scale of the potential damage but also their highly concentrated spatial distribution, revealing a clear nexus of urban vulnerability.\u003c/p\u003e\u003cdiv id=\"Sec16\" class=\"Section2\"\u003e\u003ch2\u003e5.1 Aggregate Economic Impacts\u003c/h2\u003e\u003cp\u003eAggregating the projected damages across all 16 coastal units reveals a substantial and growing economic liability. The costs, representing a conservative lower-bound estimate focused only on agriculture and roads, escalate dramatically through the 21st century. As shown in Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e, the total combined damage costs are projected to increase significantly over time, driven predominantly by the accelerating costs of infrastructure degradation. While agricultural losses are considerable, they are dwarfed by the immense costs associated with the premature failure and required replacement of road networks, particularly in the latter half of the century. This finding highlights a critical shift in the nature of climate-related water risk in urbanizing regions, where the value of built assets at risk can far exceed the value of agricultural production.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eSummary of Projected Economic Damages from Rising Groundwater Levels (Billion L.E.)\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"5\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eImpact Category\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eDamage Cost by 2050\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eDamage Cost by 2080\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eDamage Cost by 2100\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c5\"\u003e\u003cp\u003eTotal Damage (2030\u0026ndash;2100)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eAgricultural Losses\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e0.08\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e0.38\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.93\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eRoad Network Damage\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e77.26\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e131.18\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e212.42\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e420.86\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eTotal\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e\u003cp\u003e\u003cb\u003e77.34\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e\u003cb\u003e131.56\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e\u003cb\u003e213.35\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c5\"\u003e\u003cp\u003e-\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"5\"\u003e\u003cem\u003eNote: Costs for each period (e.g., 2050) represent the cumulative additional cost incurred during the preceding interval (e.g., 2030\u0026ndash;2050). The total damage for roads represents the sum of these interval costs. Agricultural losses are annual projections for the specified year.\u003c/em\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec17\" class=\"Section2\"\u003e\u003ch2\u003e5.2 Spatial Disaggregation of Impacts: A Story of Urban Concentration\u003c/h2\u003e\u003cp\u003eThe most critical finding of the analysis is the profoundly uneven spatial distribution of these economic risks. The damages are not spread evenly along the coast but are overwhelmingly concentrated in the densely populated, economically vital, and low-lying coastal units of the Nile Delta. The analysis reveals that the coastal units corresponding to the Nile Delta (CU2: Alexandria, CU3: Behaira-Kafr El Sheikh, and CU4: Dakahlia-Damietta) are projected to bear \u003cb\u003e98.8%\u003c/b\u003e of the total damage costs by the year 2100 (Abdrabo \u0026amp; Hassaan, 2024). In contrast, the more arid and less developed units of the Northwestern Coast (CU1) and North Sinai (CU6), along with Port Said (CU5), collectively account for just over 1% of the total damages (Table\u0026nbsp;\u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e).\u003c/p\u003e\u003cp\u003eThis spatial concentration creates a clear vulnerability nexus where high-value infrastructure and dense populations coincide with acute hydrogeological susceptibility. The results for specific urban units are particularly illustrative:\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eAlexandria (CU2-SUB1)\u003c/b\u003e: The projected damage to the road network in this single metropolitan unit is estimated to be L.E. 17.2\u0026nbsp;billion between 2030\u0026ndash;2050, rising to L.E. 25.8\u0026nbsp;billion for 2050\u0026ndash;2080, and a staggering L.E. 129\u0026nbsp;billion for 2080\u0026ndash;2100. The total projected road damage for Alexandria alone amounts to L.E. 172\u0026nbsp;billion, representing a massive fiscal threat to the governorate (Abdrabo \u0026amp; Hassaan, 2024).\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eNile Delta Units (CU3 \u0026amp; CU4)\u003c/b\u003e: These units, which combine dense agricultural land with significant urban centers and infrastructure, also face enormous costs. For example, the West Burullus unit (CU3-SUB2) is projected to face total road damage costs of L.E. 77.7\u0026nbsp;billion, while the New Damietta-Ras El Barr unit (CU4-SUB2) faces costs of L.E. 63.6\u0026nbsp;billion through 2100 (Abdrabo \u0026amp; Hassaan, 2024).\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eWestern Desert Units (CU1)\u003c/b\u003e: In stark contrast, the damages in the less developed western units are orders of magnitude smaller. The total road damage cost for the entire Marsa Matrouh unit (CU1-SUB3) through 2100 is projected at L.E. 3.0\u0026nbsp;billion, while the Sallum unit (CU1-SUB1) faces a total cost of only L.E. 0.5\u0026nbsp;billion (Abdrabo \u0026amp; Hassaan, 2024).\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003cp\u003eThis dramatic spatial disparity underscores that while rising groundwater is a regional physical phenomenon, its economic consequences are fundamentally an urban problem, driven by the location and value of man-made assets as shown in Table \u003cspan refid=\"Tab5\" class=\"InternalRef\"\u003e5\u003c/span\u003e.\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab5\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 5\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003eSpatial Concentration of Projected Total Economic Damages by 2100\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eCoastal Unit Group\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003eDescription\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eTotal Damage Cost (Billion L.E.)\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eShare of Total Damage (%)\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCU1\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNorthwestern Coast\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e4.96\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.25%\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCU2\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eAlexandria\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e210.02\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e10.97%\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCU3\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWest \u0026amp; Central Delta\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e984.51\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e51.43%\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCU4\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eEast Delta\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e696.64\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e36.39%\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCU5\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePort Said\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e14.71\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.77%\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003e\u003cb\u003eCU6\u003c/b\u003e\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNorth Sinai\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e\u003cp\u003e3.58\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e\u003cp\u003e0.19%\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003ctfoot\u003e\u003ctr\u003e\u003ctd colspan=\"4\"\u003e\u003cem\u003eNote: Total damage cost is the sum of projected agricultural losses in 2100 and cumulative road damage from 2030\u0026ndash;2100. Percentages are derived from these totals.\u003c/em\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tfoot\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec18\" class=\"Section2\"\u003e\u003ch2\u003e5.3 Temporal Evolution of Risk\u003c/h2\u003e\u003cp\u003eThe analysis demonstrates a clear temporal escalation of risk. The damage costs projected for the near term (2030\u0026ndash;2050) are significant but are substantially lower than those projected for the latter half of the century. For example, the total road damage cost for the Behaira unit (CU3-SUB1) is L.E. 21.3\u0026nbsp;billion for the 2030\u0026ndash;2050 period, but it nearly doubles to L.E. 41.2\u0026nbsp;billion for the 2050\u0026ndash;2080 period (Abdrabo \u0026amp; Hassaan, 2024). This pattern is consistent across all high-risk units, indicating that the most severe economic consequences of climate-induced groundwater changes are a long-term liability. Current development decisions made without consideration for these future costs are effectively locking in massive, unfunded mandates for future generations as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig9\" class=\"InternalRef\"\u003e9\u003c/span\u003e.\u003c/p\u003e\u003c/div\u003e"},{"header":"6. Discussion","content":"\u003cp\u003eThe results of the valuation exercise provide more than just a set of numbers; they offer a fundamental reframing of the relationship between groundwater, climate change, and urban development. By translating a complex hydrogeological threat into the universal language of economic cost, the analysis makes the invisible visible, with profound implications for policy and planning.\u003c/p\u003e\u003cdiv id=\"Sec20\" class=\"Section2\"\u003e\u003ch2\u003e6.1 Interpreting the Scale of the Economic Threat\u003c/h2\u003e\u003cp\u003eThe multi-billion L.E. damage projections represent a massive, unfunded contingent liability for the Egyptian state and its coastal municipalities. These figures are not abstract environmental costs but foreshadow future budgetary crises. The projected L.E. 172\u0026nbsp;billion in additional road replacement costs for Alexandria alone is a figure that would overwhelm any municipal capital improvement budget, threatening the city's fiscal solvency and its ability to provide basic services. This analysis fundamentally reframes the \"problem\" of rising groundwater. It is not merely a technical issue for hydrologists to monitor, but a critical fiscal and governance challenge for mayors, finance ministers, and national planners. By quantifying the \"cost of inaction,\" the valuation provides a powerful economic rationale for proactive investment in adaptation, transforming the discourse from one of environmental protection to one of fiscal prudence and risk management.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec21\" class=\"Section2\"\u003e\u003ch2\u003e6.2 The Contribution of an Integrated Framework\u003c/h2\u003e\u003cp\u003eThis study's primary contribution lies in demonstrating a methodology that overcomes the disciplinary and policy silos identified as a key barrier in the literature (Shrestha et al., 2020; Morris et al., 2000). While previous research has critiqued the fragmentation between water management and urban planning, this paper provides a practical, quantitative tool to force their integration. The Integrated Hydro-Economic Valuation Framework serves as a \"boundary object\"\u0026mdash;a common analytical platform where hydrologists, economists, and urban planners can bring their respective data and models to produce a shared, policy-relevant output. It moves beyond simply stating that a policy gap exists and demonstrates \u003cem\u003ehow\u003c/em\u003e to bridge it. The spatial concentration of risk revealed in the results illuminates a potential future political economy of adaptation. The overwhelming concentration of projected costs in the Nile Delta provides a rational basis for prioritizing national adaptation funds. However, this could also create political tensions with less-affected regions, highlighting the need for transparent, evidence-based allocation mechanisms that such valuation studies can provide.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec22\" class=\"Section2\"\u003e\u003ch2\u003e6.3 Linking Hydrology, Economics, and Urban Form\u003c/h2\u003e\u003cp\u003eThe findings underscore that economic vulnerability to groundwater changes is a product of the interaction between three distinct systems: the hydrogeological system (physical exposure), the economic system (valuation of assets), and the urban system (the spatial arrangement and density of those assets). The staggering costs for Alexandria are not simply because its groundwater is rising, but because it is a dense, high-value concentration of infrastructure and population located on a susceptible low-lying delta. In contrast, the western coastal units, despite similar physical exposure to SLR, face far lower economic damage due to their different urban form and lower asset density. This confirms the paper's central relevance to the field of urban development: managing hydrogeological risk is inextricably linked to managing urban form. Decisions about where and how to build have direct and quantifiable consequences for future climate-related economic liabilities.\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec23\" class=\"Section2\"\u003e\u003ch2\u003e6.4 Limitations and Avenues for Expansion\u003c/h2\u003e\u003cp\u003eIt is crucial to acknowledge the limitations of this valuation, which reinforce the conclusion that the presented figures are conservative, lower-bound estimates. The analysis was intentionally focused on two impact pathways\u0026mdash;agriculture and roads\u0026mdash;for which robust data and clear dose-response relationships were available. Numerous other significant impacts were not quantified, including:\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eDamage to Buildings and Foundations\u003c/b\u003e: Rising groundwater can cause structural damage to buildings through soil saturation, subsidence, and corrosion of foundations, a potentially enormous cost category in dense urban areas (Abdrabo \u0026amp; Hassaan, 2024).\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eSubterranean Infrastructure\u003c/b\u003e: The accelerated corrosion and failure of water supply, sanitation, and utility networks buried underground represent another major un-costed liability (Abdrabo \u0026amp; Hassaan, 2024).\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003ePublic Health Impacts\u003c/b\u003e: Higher water tables can lead to dampness in buildings, failure of on-site sanitation systems, and increased incidence of waterborne diseases, carrying significant public health costs (Abdrabo \u0026amp; Hassaan, 2024).\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eLoss of Groundwater-Dependent Ecosystem Services (GDEs)\u003c/b\u003e: As noted in the literature review, the degradation of coastal wetlands and other GDEs due to changes in groundwater regimes represents a significant loss of ecological and economic value that remains unquantified (Aziz et al., 2025; Griebler \u0026amp; Avramov, 2015).\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003cp\u003eThese un-valued impacts suggest the true economic cost of inaction is likely far greater than estimated here. This highlights the urgent need for future research to expand the scope of valuation to create a more complete picture of the total economic risk.\u003c/p\u003e\u003c/div\u003e"},{"header":"7. Policy Implications","content":"\u003cp\u003eThe quantification of economic damages is not an academic exercise; its ultimate purpose is to inform and catalyze more effective policy and planning. The findings from this study have direct and actionable implications for decision-makers at the municipal, regional, and national levels. The valuation results provide the evidence base needed to move from a reactive to a proactive and spatially targeted approach to managing groundwater-related climate risks.\u003c/p\u003e\u003cdiv id=\"Sec25\" class=\"Section2\"\u003e\u003ch2\u003e7.1 For Urban and Land-Use Planning\u003c/h2\u003e\u003cp\u003eThe spatially explicit damage projections can serve as a powerful new data layer for urban and regional planners, enabling a shift towards risk-informed development.\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eRisk-Informed Zoning and Development Control\u003c/b\u003e: The high-damage zones identified in the analysis (e.g., large parts of Alexandria and the Delta coast) should be designated as special planning areas. Stricter regulations should be applied, potentially prohibiting the construction of new critical infrastructure (hospitals, power plants, major transport links) in the most vulnerable locations and requiring climate-resilience measures for all new developments.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eCapital Improvement Planning\u003c/b\u003e: Municipalities can use the projected infrastructure damage costs to reprioritize their long-term capital improvement plans. The analysis provides a clear economic justification for directing investment towards proactive measures, such as upgrading urban drainage systems, retrofitting roadbeds with more resilient materials, and protecting existing infrastructure in high-risk zones, rather than waiting to incur much higher future repair and replacement costs.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eBuilding Codes and Standards\u003c/b\u003e: The findings support the case for revising national and municipal building codes to mandate standards for groundwater resilience in vulnerable coastal areas. This could include requirements for elevated foundations, use of water-resistant building materials, and integrated site-level water management systems.\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec26\" class=\"Section2\"\u003e\u003ch2\u003e7.2 For Sustainable Groundwater Management\u003c/h2\u003e\u003cp\u003eThe immense \"cost of inaction\" demonstrated by the valuation provides a compelling economic argument for investing in sustainable groundwater management as a form of risk reduction as shown in Table \u003cspan refid=\"Tab6\" class=\"InternalRef\"\u003e6\u003c/span\u003e.\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eJustifying Investment in Monitoring\u003c/b\u003e: The study underscores the value of robust data. The economic risks justify significant public investment in comprehensive, real-time groundwater monitoring networks to track changes in water levels and quality, which are essential for validating models and guiding adaptive management (Morris et al., 2000; La Vigna et al., 2022).\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003ePromoting Managed Aquifer Recharge (MAR)\u003c/b\u003e: The valuation makes a strong business case for proactive interventions like MAR. By investing in systems to capture and recharge aquifers with excess surface water or treated wastewater, authorities can help counteract rising water tables and saltwater intrusion, framing these nature-based solutions as cost-effective investments that avoid far greater future damages (C40 Knowledge Hub, 2025; van der Schyff et al., 2024; Hashemi \u0026amp; Berndtsson, 2022).\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eIntegrating Land and Water Governance\u003c/b\u003e: The framework itself provides a model for the integrated governance that is critically lacking (Shrestha et al., 2020). The results should be used to mandate joint planning committees between water resource agencies and urban planning authorities, using the shared language of economic risk to align their objectives and policies.\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003c/div\u003e\u003cdiv id=\"Sec27\" class=\"Section2\"\u003e\u003ch2\u003e7.3 For National Climate Adaptation and Fiscal Policy\u003c/h2\u003e\u003cp\u003eAt the national level, the valuation provides the macroeconomic data needed to elevate groundwater management on the national agenda.\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eQuantifying National Adaptation Needs\u003c/b\u003e: The aggregated damage costs provide a credible, evidence-based figure for Egypt's National Adaptation Plan and its submissions to international climate finance mechanisms like the Green Climate Fund. It demonstrates the scale of funding required to adapt the nation's vulnerable coastal infrastructure.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003e\u003cb\u003eInforming National Fiscal Risk Assessment\u003c/b\u003e: The projected damages represent a significant contingent liability for the national government. These quantified risks should be formally incorporated into the Ministry of Finance's long-term fiscal risk registers, ensuring that future budgetary planning accounts for these escalating climate-related costs.\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003cp\u003e\u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab6\" border=\"1\"\u003e\u003ccaption language=\"En\"\u003e\u003cdiv class=\"CaptionNumber\"\u003eTable 6\u003c/div\u003e\u003cdiv class=\"CaptionContent\"\u003e\u003cp\u003ePolicy Recommendations Matrix\u003c/p\u003e\u003c/div\u003e\u003c/caption\u003e\u003ccolgroup cols=\"4\"\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e\u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e\u003cthead\u003e\u003ctr\u003e\u003cth align=\"left\" colname=\"c1\"\u003e\u003cp\u003eValuation Finding\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c2\"\u003e\u003cp\u003ePolicy Domain\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c3\"\u003e\u003cp\u003eSpecific Recommendation\u003c/p\u003e\u003c/th\u003e\u003cth align=\"left\" colname=\"c4\"\u003e\u003cp\u003eLead Agency/Level\u003c/p\u003e\u003c/th\u003e\u003c/tr\u003e\u003c/thead\u003e\u003ctbody\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eHigh projected road damage costs in Alexandria (\u0026gt;\u0026thinsp;L.E. 170\u0026nbsp;billion).\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eUrban Planning / Infrastructure\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eRevise municipal capital improvement plan to prioritize drainage upgrades and roadbed retrofitting in vulnerable districts.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eAlexandria Governorate; Ministry of Planning\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eEscalating agricultural losses in the Nile Delta.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWater \u0026amp; Agricultural Policy\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eInvest in research and extension services for waterlogging-resistant crop varieties and improved on-farm drainage systems.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMinistry of Water Resources; Ministry of Agriculture\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eExtreme concentration of risk in CU2, CU3, CU4.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNational Climate Adaptation\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003ePrioritize allocation of national and international adaptation funds to infrastructure resilience projects in the Nile Delta.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMinistry of Environment; Ministry of International Cooperation\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eWidespread infrastructure vulnerability across all coastal units.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eNational Planning / Law\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eUpdate national building codes for coastal zones to include standards for groundwater-resilient foundations and infrastructure design.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMinistry of Housing, Utilities \u0026amp; Urban Communities\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003ctr\u003e\u003ctd align=\"left\" colname=\"c1\"\u003e\u003cp\u003eEntire analysis predicated on modeled projections.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c2\"\u003e\u003cp\u003eWater Resource Management\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c3\"\u003e\u003cp\u003eExpand and upgrade the national groundwater monitoring network along the Mediterranean coast for model validation and early warning.\u003c/p\u003e\u003c/td\u003e\u003ctd align=\"left\" colname=\"c4\"\u003e\u003cp\u003eMinistry of Water Resources and Irrigation\u003c/p\u003e\u003c/td\u003e\u003c/tr\u003e\u003c/tbody\u003e\u003c/colgroup\u003e\u003c/table\u003e\u003c/div\u003e\u003c/p\u003e\u003c/div\u003e"},{"header":"8. Conclusion","content":"\u003cp\u003eThis paper began with the premise that groundwater, the invisible foundation of urban resilience, is systematically undervalued in policy and planning, leading to unsustainable and risky development pathways. By developing and applying an Integrated Hydro-Economic Valuation Framework to the case of Egypt's Mediterranean coast, this research has made a significant contribution toward rectifying this omission. The study's primary contribution is a robust, interdisciplinary, and replicable methodology that successfully integrates hydrology, economics, and urban planning to generate decision-relevant evidence. It provides a pragmatic blueprint for how the \"invisible\" costs of groundwater degradation can be made visible in the economic terms that drive policy.\u003c/p\u003e\u003cp\u003eThe application of this framework yielded a stark and urgent conclusion: failing to account for climate-induced changes in groundwater carries immense and quantifiable economic costs that threaten the long-term sustainability of coastal urban regions. The multi-billion L.E. damages projected for Egypt's coast are not a distant, abstract environmental problem; they are a looming fiscal crisis that will manifest in failing infrastructure, reduced economic productivity, and constrained municipal budgets. The highly concentrated nature of this risk in the urbanized Nile Delta underscores that groundwater vulnerability is fundamentally an urban development challenge, demanding solutions rooted in spatial planning, infrastructure management, and governance reform.\u003c/p\u003e\u003cp\u003eThe ultimate takeaway is that sustainable urban development and sustainable groundwater management are not separate objectives but two sides of the same coin. The long-term viability of our cities depends on recognizing and managing the hydrogeological systems upon which they are built. Ignoring this invisible foundation will lead to staggering and entirely foreseeable economic and social costs.\u003c/p\u003e\u003cp\u003eThis research opens several critical pathways for future inquiry. First, the scope of valuation must be expanded. Future work should aim to incorporate the significant non-market values and ecosystem services\u0026mdash;such as damage to building foundations, public health impacts, and the degradation of GDEs\u0026mdash;that were beyond the scope of this study, in order to capture the total economic cost more comprehensively. Second, the framework's versatility should be tested by applying it to different urban and hydrogeological contexts, such as inland cities facing groundwater depletion and land subsidence, to broaden its applicability. Finally, future research must integrate a social equity lens, analyzing the distributional impacts of both groundwater changes and proposed policy responses to ensure that adaptation measures do not disproportionately burden the most vulnerable populations within cities. By pursuing these avenues, the research community can continue to build the evidence base needed to recalibrate urban development for a truly resilient and water-secure future.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eData Availability Statement:\u0026nbsp;\u003c/strong\u003eThe data sets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding Declaration:\u003c/strong\u003e No funding was received for conducting this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical Trial Number:\u003c/strong\u003e Not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to Participate Declaration:\u003c/strong\u003e Not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to Publish Declaration:\u003c/strong\u003e Not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics Declaration:\u003c/strong\u003e Not applicable.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eT.O. is the sole author of this manuscript and was responsible for the conception, analysis, writing, and preparation of all figures and tables\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eAbdrabo, M. 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Valuation of Groundwater-Dependent Ecosystems: A Case Study of Handan, China. \u003cem\u003eWater\u003c/em\u003e, 12(5), 1455.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"discover-sustainability","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"disu","sideBox":"Learn more about [Discover Sustainability](https://www.springer.com/43621)","snPcode":"","submissionUrl":"","title":"Discover Sustainability","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"groundwater, urban resilience, economic valuation, sustainability, ecosystem services, climate adaptation, urban planning","lastPublishedDoi":"10.21203/rs.3.rs-7846108/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7846108/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eGroundwater is a critical yet often invisible resource underpinning the resilience of urban areas, particularly in coastal zones facing climate change. Despite its importance, groundwater is systematically undervalued and poorly integrated into urban planning and policy, leading to unsustainable development pathways. This paper introduces a novel Integrated Hydro-Economic Valuation Framework designed to make the economic consequences of groundwater changes visible and actionable for urban decision-makers. The framework links physical hydrogeological changes to impacts on urban systems and quantifies them in monetary terms. We apply this framework to a comprehensive case study of Egypt's Mediterranean coast, a rapidly urbanizing region representative of many coastal zones in the Global South. Using a high-emissions climate scenario (RCP8.5), we project rising groundwater levels due to sea-level rise and value the subsequent damages to agriculture and road infrastructure across 16 coastal units through 2100. The results reveal substantial and escalating economic costs, projected to reach billions of L.E., with over 98% of the damage concentrated in the densely populated urban and economic hubs of the Nile Delta, including Alexandria. These findings demonstrate that failing to account for groundwater changes creates a massive, unfunded liability that threatens municipal solvency and long-term sustainability. The paper concludes by providing concrete policy recommendations for integrating these valuation outcomes into risk-informed urban planning, infrastructure investment, and climate adaptation strategies. This research provides a robust, replicable methodology for cities worldwide to quantify the hidden costs of groundwater degradation and recalibrate their development trajectories for a water-secure future.\u003c/p\u003e","manuscriptTitle":"Valuing Groundwater Impacts for Sustainable Urban Planning in Coastal Cities","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-11-26 08:39:02","doi":"10.21203/rs.3.rs-7846108/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-02-23T08:44:12+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-06T21:14:22+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-02-04T22:42:07+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"211309182878795075139660372827820327552","date":"2026-02-02T17:02:40+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"272403964494228115747244143196663467478","date":"2026-01-29T17:28:04+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"216925858956748609927433781327888398890","date":"2026-01-28T10:52:49+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-01-05T00:24:10+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"296951253527096832906583838785212491931","date":"2025-11-19T23:35:13+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2025-11-14T11:02:18+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-11-06T07:41:12+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-10-30T10:21:20+00:00","index":"","fulltext":""},{"type":"submitted","content":"Discover Sustainability","date":"2025-10-30T10:18:09+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"discover-sustainability","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"disu","sideBox":"Learn more about [Discover Sustainability](https://www.springer.com/43621)","snPcode":"","submissionUrl":"","title":"Discover Sustainability","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Discover Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"d93f97ca-ce4c-40f5-a26c-814074ff70a2","owner":[],"postedDate":"November 26th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"in-revision","subjectAreas":[],"tags":[],"updatedAt":"2026-05-13T06:28:40+00:00","versionOfRecord":[],"versionCreatedAt":"2025-11-26 08:39:02","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7846108","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7846108","identity":"rs-7846108","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}