Climate change, growing urban pollution, and increasing water scarcity are forcing cities to adopt strategies that enhance resilience to both climatic and anthropogenic pressures. The Barcelona Superblock model is a novel urban planning strategy that highly restricts vehicle traffic, converts streets into pedestrian-priority corridors, and promotes green spaces. Within this framework, green infrastructures, also called sustainable urban drainage systems (SUDS), are implemented as local, site-specific measures to capture (i.e., flood control), treat, and infiltrate treated stormwater (i.e., aquifer recharge). To evaluate the Superblock model impact on urban water quality, we conducted seven sampling campaigns across three Barcelona districts, targeting rainfall, stormwater "first-flush" from roads and pedestrianized streets, as well as SUDS influent and effluent within and in the vicinity to Superblocks, with a focus on dissolved trace metals and dissolved organic matter (DOM). Results showed that Superblocks reduced pollutant loads and mitigated ecotoxicological risks. Trace metal and DOM concentrations followed the trend: Rain < SUDS effluent < Pedestrian Street runoff < Road runoff, highlighting traffic-related impacts and SUDS treatment capacity (23-70% in best case scenario). Risk assessment indicated episodic ecotoxicological risk in stormwater, especially in road runoff due to elevated concentrations of Cu and Zn, while SUDS consistently remained below risk thresholds. SUDS also transform DOM into more stable, humic-like forms. Trace metals and DOM emerged as biogeochemical proxies for stormwater quality, enabling more effective and sustainable urban water management. These findings support the integration of Superblock-like strategies into urban planning to control and reduce contaminant urban discharges.

Social sustainability is often insufficiently addressed in urban water management, particularly regarding equity, inclusion, and governance processes, which constrain progress toward resilient and socially just urban water systems. This study introduces and applies an indicator-based, framework-driven analytical approach to operationalize social sustainability in urban water management. Four principal dimensions—awareness, water-use practices, equity, and inclusion are assessed using a structured semi-quantitative scoring system, complemented by qualitative interpretation. The framework is implemented in two contrasting urban contexts, Peshawar (Pakistan) and Al-Jouf (Saudi Arabia), to investigate how varying socio-economic, climatic, and governance conditions influence social sustainability outcomes within a unified analytical structure. Descriptive statistics, radar-based visualization, sustainability gap assessment, and scenario-based sensitivity analysis are employed to evaluate indicator performance and relative influence. The aggregated findings indicate that the composite social sustainability index achieves approximately 38% of its normalized theoretical maximum, reflecting moderate to low social sustainability within the assessed framework. Awareness and water-use practices demonstrate moderate indicator performance, whereas equity and inclusion consistently exhibit weak outcomes across both contexts. Sensitivity analysis reveals that hypothetical enhancements in equity and inclusion produce significantly greater improvements in overall index performance (approximately 18–22%) compared to similar changes in awareness or behavioral indicators, underscoring the predominant role of governance-related dimensions in the model. Rather than highlighting numerical disparities between cities, the comparative analysis uncovers structurally similar constraints on social sustainability across cities with divergent development and institutional settings. The results underscore that while improvements in awareness and individual behavior are necessary, they are insufficient to achieve socially sustainable urban water management without equity-focused governance reforms and inclusive institutional mechanisms. By rendering social sustainability dimensions analytically explicit and comparable, the framework facilitates more informed governance reflection and establishes a basis for future empirical integration and policy evaluation in urban water systems.

Green stormwater infrastructure (GSI) is recognized as a sustainable urban water management solution. However, community stewardship remains low for various reasons, many of which are socio-cognitive and context-specific. This research applies the Theory of Planned Behavior (TPB) to explore the role of knowledge, experience, attitudes, subjective norms, perceived behavioral control, and demographic factors in predicting residents’ GSI stewardship intentions. Through an online survey and multilevel regression modeling, we analyzed data from 418 participants across three U.S. cities: Baltimore, MD, Pittsburgh, PA, and Portland, OR. Results show that perceived behavioral control and subjective norms significantly predicted GSI stewardship intentions, while attitudes did not. GSI knowledge affected stewardship intentions while positively influencing all other TPB constructs, particularly perceived behavioral control. Demographics, including homeownership, income, political ideology, race, and housing type, influenced TPB constructs, particularly attitudes. Findings highlight the importance of resource accessibility, social influence, and targeted knowledge dissemination in promoting GSI stewardship.

Milan city faces challenges in urban water management due to fluctuating groundwater levels. To better characterize the groundwater system, this study aimed at identifying spatiotemporal patterns in piezometric data and exploring their relationship with different factors through statistical techniques. Groundwater level data were divided into historical and recent periods and analysed for autocorrelation and correlation with gridded precipitation data, pumped volumes, and imperviousness data at different temporal scales. Results revealed an overall rising trend of Milan’s water table with groundwater levels clustering in six groups at different areas from north to south of Milan, suggesting the influence of site-specific characteristics. Insights into the interplay of drivers influencing Milan’s groundwater system reveal a weak correlation with precipitation, alongside an inverse correlation with groundwater withdrawals and land use change. This study evidences the complexity of this system, offering a basis for future research to support sustainable urban water management.

ABSTRACT Water sensitivity is progressively recognised as a critical pathway for achieving sustainable and resilient urban water management, particularly in riverine cities where ecological integrity, infrastructure performance and governance effectiveness are tightly interconnected. While the Water-Sensitive Cities Index (WSCI) has been widely applied in metropolitan contexts, its application to smaller and secondary riverine cities remains limited, particularly in developing countries such as India. This study develops and applies a context-specific water sensitivity assessment framework for Paonta Sahib, a secondary riverine city located along the Yamuna River. The framework adapts the WSCI through indicator customisation and integrates quantitative indices with qualitative, stakeholder-driven assessments across four dimensions: society, environment, technology, and governance, represented by 22 indicators. Results indicate an overall WSCI score of 0.41, placing Paonta Sahib in a neutral (moderately sensitive) transition stage. Society (0.58) and technology (0.54) demonstrate relatively stronger performance, while governance (0.37) and environment (0.29) reveal critical deficits. The analysis identifies key opportunities for advancing water sensitivity through nature-based solutions, wastewater reuse, groundwater recharge, circular economy practices and strengthened participatory governance. Finally, this study provides a replicable assessment approach that supports both scholarly evaluation and actionable urban water management strategies in similar contexts.

Climate change is widening the mismatch between water supply and water demand in urban areas, affecting both. Additionally, water demand is increasing due to population growth and economic development. Water allocation is a key component of sustainable urban water management and, unlike traditional approaches, must rely on a fit-for-purpose principle, where water is valued by its quality adequacy based on the use rather than by its source, with water reuse playing a central role in urban water resilience. This paper presents a novel framework, together with the step-by-step process for its application—the smart water allocation process (SWAP) for urban non-potable uses—and the developed software toolset to facilitate the decision-making process by urban managers, water utilities, and other stakeholders. It was developed within the context of a living lab to accelerate the innovation uptake. The demand–supply matchmaking and the plan module are comprehensively described and the SWAP results and their contribution to water resilience in Lisbon are discussed. Three water allocation alternatives were defined to implement different strategies, conservation, redundancy and reuse, in two green area clusters. Synergy with climate action funding was identified. The application of the SWAP enabled decision-making based on factual evidence and fostered intuitive understanding of the urban water resilience challenges.

Rapid urban development has increased impervious surface coverage, causing higher surface runoff and reduced rainwater infiltration that contribute to flooding and groundwater depletion. Permeable pavement systems, such as paving blocks, are widely applied to support sustainable urban water management. This study analyzes the effect of land slope covered with hexagonal paving blocks on rainwater infiltration performance. Laboratory experiments were conducted using a rainfall simulator with a constant intensity of 50 mm/h. Three slope variations were evaluated, namely 0%, 2%, and 4%. The paving blocks had a compressive strength of 25 MPa (Class B) and were installed on a compacted sandy bedding layer. Infiltration and surface runoff volumes were measured at five-minute intervals until stable conditions were achieved. Results indicate that land slope significantly influences infiltration behavior. The highest infiltration performance occurred at a 2% slope, with a maximum infiltration volume of approximately 570 mL recorded between the 40th and 45th minutes. Conversely, the 0% slope showed decreased infiltration due to soil saturation, while the 4% slope exhibited lower efficiency because the increased slope accelerated surface runoff. These findings demonstrate that hexagonal paving blocks installed on a moderate slope enhance infiltration, reduce runoff, and support urban flood mitigation and groundwater recharge.

This study examines the economic viability and environmental sustainability of implementing a rainwater harvesting (RWH) system in a six-story commercial office building through the integration of Cost–Benefit Analysis (CBA) and Life Cycle Assessment (LCA). Rapid urbanization, increasing water demand, and rising utility costs have intensified the need for alternative water management strategies in commercial developments. The proposed RWH system captures rooftop runoff, treats it through filtration units, and reuses the collected water for non-potable applications such as toilet flushing and landscape irrigation. The Cost–Benefit Analysis evaluates capital, operational, maintenance, and end-of-life costs against long-term financial benefits, including reduced municipal water consumption, lower wastewater fees, and resilience against future water tariff increases over a 20-year project life. Meanwhile, the Life Cycle Assessment assesses environmental impacts across manufacturing, installation, operation, and disposal phases. Results indicate that although the system entails significant upfront investment, the long-term economic savings outweigh total costs, yielding a favorable benefit–cost ratio. Environmental analysis further demonstrates net positive outcomes through reduced potable water use, lower energy consumption for water treatment, and decreased wastewater generation. Overall, the findings support rainwater harvesting as a practical, cost-effective, and environmentally responsible solution for commercial office buildings, contributing to sustainable urban water management and long-term operational efficiency.

Sustainable urban water management extends beyond technical infrastructure, relying on organizational capacity, effective governance and adaptive strategies that foster resilience and innovation. In many developing contexts, public water utilities face institutional and operational constraints that limit sustainable performance. This study examines organizational and governance determinants of water system effectiveness in Lagos, Nigeria, developing an empirical SEM-based framework to explain their interactions. Using a systematic review, expert interviews and a practitioner survey analyzed via Exploratory Factor Analysis and Partial Least Squares Structural Equation Modeling, the study identifies two core organizational dimensions—Operational Capability in Water Systems (OCWS) and Sustainability Governance and Innovation (SGI)—and three strategic clusters that enhance performance. Findings highlight the role of collaborative capacity, governance innovation, and cross-institutional coordination, aligning with sustainable infrastructure and organizational symbiosis principles. The framework advances existing sustainability models by integrating organizational capability and governance innovation into water utility performance assessment. Practical implications include strengthening institutional capacity, embedding innovation-focused governance mechanisms, and promoting inter-agency collaboration. Future research could apply this framework in other contexts or assess policy reforms that support resilient, sustainable urban water management.

This study evaluated powdered activated carbon (PAC) pre-coating as a pretreatment strategy to enhance dissolved organic matter (DOM) removal and control fouling during microfiltration of surface water. Two PAC types (one is coal-based and the other is wood-based), divided into three different particle size ranges (22–44, 44–63, 63–88 μm) using sieves and coating weights ranging from 0.6 to 1.2 and 2.4 mg/cm2, were systematically compared. Coating PAC improved the quality of water after filtration and stabilized filtration flux, with smaller PAC particle size ranges exhibiting higher DOM removal efficiencies, achieving maximum removals of approximately 30–35% for DOC and over 50% for UV260 at the highest coating weight, whereas uncoated membranes showed negligible DOM removal. The resulting PAC layer on the membrane increased filtration resistance. Fluorescence EEM and Mw distribution results showed that aromatic and high molecular weight DOM was preferentially adsorbed by PAC before reaching the membrane surface; therefore, their contribution to membrane fouling could be reduced. SEM observations showed differences in the images of deposits formed on the PAC layer. These results indicate that the PAC layer acted as a protective interception zone that reduced direct contact between DOM and the membrane surface, thereby contributing to improved flux stability. The coating effect varied with the weight, type and size range of PAC, highlighting the importance of PAC selection. The findings of this study could contribute to more efficient and sustainable urban water supply system operation and management through water quality improvement and process configuration.

Urban water systems in developing cities face increasing pressure from rapid population growth, aging infrastructure, and climate variability. This study examines the resilience and resistance of domestic water consumption in the Jos Metropolitan Area (JMA), using the Material Flow Analysis (MFA) framework. Data were obtained through a household survey of 400 respondents, supported by supply records from the Plateau State Water Board. The findings reveal an average per capita consumption of 44.6 liters per day, an average household size of 5 persons, and an estimated 20% water loss due to leakages and inefficient distribution. The Resistance Index (0.80) indicates strong short-term stability, suggesting that households effectively cope with supply interruptions through storage and alternative sourcing. However, the Resilience Index (0.62) reflects moderate recovery and limited adaptive capacity, constrained by infrastructural decay, unequal access, and weak institutional coordination. The combined MFA and resilience assessment highlight a system that is robust yet inflexible able to endure short-term shocks but slow to recover sustainably. The study recommends infrastructure renewal, data-driven planning, and community-based adaptation to enhance long-term water resilience. Integrating MFA into local governance frameworks can strengthen monitoring, reduce losses, and promote sustainable urban water management in Jos and similar mid-sized African cities.

Sustainable urban water management is increasingly challenged by uncertainty, imprecision, and hesitancy in evaluating alternative water sources. This study proposes a novel multi-criteria decision-making (MCDM) framework based on fractional orthopair fuzzy (FOF) sets, designed to model partial hesitancy and fractional expert judgments more effectively than traditional fuzzy methods. Integrating an entropy-based weighting scheme and the technique for order preference by similarity to ideal solution (TOPSIS), the framework is applied to assess water resource alternatives in Lahore, Pakistan a city facing rapid groundwater depletion, urban expansion, and declining surface water quality. The evaluation considers three key criteria: water quality, availability, and affordability across the alternatives of surface water, groundwater, and rainwater. Results show that rainwater harvesting is the most sustainable option, with a closeness coefficient of :0.8396, outperforming alternatives in terms of both cost-effectiveness and safety. Sensitivity analysis on parameters (:p, :q) confirms the model’s robustness. The findings offer actionable guidance for water authorities, emphasizing the importance of rainwater harvesting and reduced reliance on depleting groundwater. The proposed model is adaptable to other urban regions, provided expert input and contextual data are available.

Adaptive decision framework for sustainable urban water management under multi-source uncertainty: A multi-scenario and multi-model integration approach

ABSTRACT This study examines the hydrogeochemical characteristics and groundwater interactions across diverse aquifer systems in Palakkad, a water‐stressed and rapidly urbanising district in Kerala, southern India. Despite its significant dependence on groundwater, urbanisation has a profound impact on hydrological processes, particularly on groundwater quality and availability. This influence is mediated by local geology, where hard‐rock aquifers present hydrogeological complexities despite their storage capacity and contamination resistance. Understanding the interplay between urban development and groundwater quality through region‐specific studies is crucial, given the hydrochemical variations across different rock types. Using multiple analytical and geochemical modelling approaches, groundwater in Palakkad is classified as freshwater, predominantly of the calcium‐bicarbonate type, with most chemical parameters meeting WHO drinking water standards. Geochemical analysis reveals a cation dominance of Ca 2+ &gt; Na + &gt; Mg 2+ &gt; K + and an anion dominance of HCO 3 − &gt; Cl − &gt; SO 4 2− &gt; NO 3 − &gt; F − . Groundwater chemistry is primarily controlled by geogenic processes, with rock–water interactions and reverse ion exchange being the dominant mechanisms. Key processes include the dissolution of silicate minerals, particularly ferromagnesian minerals and plagioclase feldspar, alongside contributions from secondary mineral precipitation (calcium carbonate, clay minerals), gypsum dissolution and cation exchange in soils. These findings highlight that urbanisation's impact on hard‐rock aquifers involves complex interactions among geology, land‐use changes and hydrochemistry, extending beyond merely reduced recharge or direct contamination of aquifers. This underscores the critical importance of incorporating local geological and hydrogeochemical knowledge to develop effective and sustainable urban water management strategies, with significant implications for groundwater resource management in rapidly urbanising regions worldwide.

Abstract This study presents the initial results of the ORCHESTRA project and offers initial indications that the integration of advanced digital technologies with Nature-based Solutions has the potential to significantly enhance urban water management in South Tyrol, with a focus on two pilot catchments in Bolzano. The proposed framework involves the development of a digital twin, which is continuously fed by dense IoT sensor networks, recreating the hydraulic behaviour of the city in real time. In parallel, a model calibrated by a Genetic Algorithm analyse these data to forecast runoff peaks and recommend adaptive control actions. The preliminary findings emphasise the potential of this hybrid strategy as a scalable solution for sustainable urban water management and that an interdisciplinary, data-driven approach can foster the transition toward intelligent, resilient and sustainable cities.

Nitrogen pollution from stormwater runoff and domestic/industrial wastewater poses major challenges for sustainable urban water management. Decentralized nature-based solutions (NBS), including bioretention systems (BRS), constructed wetlands (CWs), and roadside swales (RS), provide sustainable treatment options but often show inconsistent nitrogen removal due to environmental variability. The anaerobic ammonia oxidation (anammox) process, a critical component of the global nitrogen cycle, has emerged as a promising pathway to enhance nitrogen removal in NBS. This review synthesizes current knowledge on the occurrence, mechanisms, and drivers of anammox in urban NBS. A Bayesian modelling approach was applied to quantify the combined effects of key environmental factors -dissolved oxygen (DO), system depth, hydraulic retention time (HRT), pH, temperature, and influent nitrogen composition-on anammox activity. Results indicate that low DO generally favours anammox, while greater depth and longer retention times help maintain stable anoxic conditions. Activity is promoted under mesophilic temperatures but declines sharply at colder ranges. Nitrite availability is a consistent limiting factor, whereas elevated ammonium concentrations and high C/N ratios can suppress activity through acidification and microbial competition. Plant presence indirectly benefits anammox by moderating DO and stabilizing pH. Additionally, this review highlights the potential of advanced pathways-simultaneous nitrification-anammox-denitrification (SNAD) and partial denitrification-anammox (PD-A)-to further improve nitrogen removal efficiency in urban NBS. By consolidating mechanistic insights, quantifying environmental drivers, and identifying key research gaps, this work provides a framework to guide the optimization of NBS design and advance sustainable nitrogen management in urban water systems.

ABSTRACT African cities have high non-revenue water (NRW) losses due to leakages, illegal connections, and meter irregularities. Inefficiencies endanger financial sustainability and service delivery in Kigali, Rwanda, where NRW was 35–45%. This study proposes a pilot intervention using Kamstrup MULTICAL® 21 smart meters and LoRaWAN® connectivity technology to reduce these losses. In three districts, 500 smart meters were installed for residential, business, and institutional consumption. Three months were spent on baseline, one month on installation, and six months on post-installation monitoring. Descriptive statistics, paired t-tests, regression models, and qualitative customer and technician questionnaires were used to analyse daily automated readings, leakage alarms, and tamper detection from the meters. Results indicated a 23% decline in NRW, 64% faster leak repair, and 41% fewer billing complaints. Real-time SMS use notifications boosted consumer confidence and efficiency.

ABSTRACT Uncontrolled urbanization and urban planning deficits for climate risks have intensified water-related challenges in cities worldwide. The sponge city concept, as an innovative climate adaptation strategy, seeks to safeguard urban populations from the negative consequences of climate change by improving resilience through sustainable water management practices. This study systematically examines the effectiveness and scalability of the sponge city concept using PRISMA-guided meta-analysis and bibliometric review. The central research question investigates whether the sponge city functions as an effective and scalable tool for climate adaptation across diverse geographical and socio-economic contexts. Utilizing a meta-analysis and bibliometric framework, the study synthesizes existing literature to identify key trends, thematic clusters, and critical knowledge gaps. The findings indicate the sponge city concept holds significant promise for sustainable urban water management, particularly in mitigating urban flooding, improving water quality, and enhancing ecological resilience. However, its effectiveness remains highly contingent upon local socio-economic and geographical conditions.

The growing need for efficient and sustainable urban water management has accelerated the adoption of smart monitoring infrastructures based on wireless sensor networks (WSNs). This study proposes a connectivity-aware methodology for the optimal deployment of wireless sensor networks (WSNs) in smart water metering systems. The approach models the wireless sensors as nodes embedded in household water meters and determines the minimal yet sufficient set of Data Aggregation Points required to ensure complete network coverage and transmission reliability. A scalable and hierarchical topology is generated by integrating an enhanced minimum spanning tree algorithm with set covering techniques and geographic constraints, leading to a robust intermediate layer of aggregation nodes. These nodes are wirelessly linked to a single cellular base station, minimizing infrastructure costs while preserving communication quality. Simulation results on realistic urban layouts demonstrate that the proposed strategy reduces network fragmentation, improves energy efficiency, and simplifies routing paths compared to traditional ad hoc designs. The results offer a practical framework for deploying resilient and cost-effective smart water metering solutions in densely populated urban environments.

Urbanization and climate change significantly worsen water quality and quantity issues, heightening the urgency to address the foregoing concerns in relation to sustainable urban water management. Water Footprint Accounting (WFA) provides a novel and holistic lens for urban water management by quantifying blue, green, and gray water footprints. Unlike conventional assessments that focus only on withdrawals, WFA captures both consumption and pollution, offering a more integrated view of sustainability. This study applies WFA to the University of the Philippines—Diliman campus, using adapted numerical methods from established literature. The approach highlights hidden water dependencies, identifies critical hotspots, and demonstrates the potential of WFA as a decision-support tool for building water-resilient campus. A modified WFA spreadsheet tool was developed to automate the calculation of the blue, green, and gray water, which was then used for UP Diliman. The calculated water footprint (WF) of UP Diliman was mapped, revealing a spatial representation of the WF and WF hotspots. The results revealed that the highest total footprint was the gray water footprint (WF) of stormwater, amounting to 146,048,674 m3/year, primarily associated with suspended solids from eroded ground surfaces during rainfall events. In contrast, the lowest footprint was the blue WF of rainwater at 1,240,989 m3/year. Spatial mapping of water footprints revealed hotspots that serve as indicators of urban characteristics: blue and gray WF hotspots in highly developed areas, and green WF hotspots in zones with significant evapotranspiration. These insights highlight hidden water dependencies, identify critical pressure points, and underscore the need for future developments to integrate water-saving technologies and Low Impact Development (LID) practices. Overall, this study demonstrates how WFA can be applied as an evidence-based decision-support tool for managing and improving urban water systems in mixed land-use settings.