Search Results (312)

Urban pluvial flooding shows clear temporal accumulation, delayed response, and spatial heterogeneity. Better flood-depth prediction from a spatiotemporal coupling perspective can support urban flood risk identification and refined management. This study develops a spatiotemporal prediction model that integrates a Transformer and graph neural network (GNN). The Transformer module captures temporal dependencies in rainfall processes and flood-depth evolution. The graph attention network (GAT) represents spatial associations constrained by terrain, drainage networks, and neighboring spatial relationships. A fusion attention mechanism then adaptively couples temporal and spatial features. This study uses multi-source data, including hourly meteorological observations, terrain, land cover, drainage networks, and water-system data. It selects the heavy rainfall event caused by Typhoon In-Fa in Huai’an City in July 2021 as a typical case. The study analyzes the temporal evolution of regional average flood depth and the spatial differentiation of inundated grid cells at the municipal scale. The results show three main findings. First, during the typical heavy rainfall event, regional average flood depth follows a continuous process of low-level stability, sustained rise, rapid increase, delayed peak, slow recession at a high level, and rapid recession. The flood peak lags behind the rainfall peak by about 3 h. This result indicates clear accumulation and delayed response in urban pluvial flooding. Second, at the municipal scale, inundated grid cells show a pattern of concentrated distribution in urban built-up areas, secondary distribution in county-level built-up areas, and scattered distribution in non-construction land. Different depth grades also show clear hierarchical differentiation. Mild and moderate inundation covers a wider area. Medium-high inundation concentrates locally. High-grade inundation appears as a small number of nested high-value cells. Third, the spatial differentiation of medium- and high-grade inundated grid cells does not result from low-lying terrain or construction land alone. It forms under the combined effects of low-lying terrain, local relative depressions, and impervious surfaces in construction land. This pattern shows clear built-up-area clustering, grade differentiation, and land-cover correspondence. The results provide methodological support and decision references for urban flood risk identification, grid-based risk management, and emergency dispatch during extreme rainfall. Full article

Sustainable Urban Drainage Systems (SUDSs) have recently emerged as an alternative to traditional drainage systems, offering better stormwater management and improved resilience in road infrastructure. However, their uptake is still slow in Small Island Developing States (SIDSs) such as Mauritius. The aim of this study was to understand the potential for integrating various SUDS in major road projects and identify existing barriers and potential enablers. Semi-structured interviews with 20 highway experts showed that for Mauritius, the most feasible solutions were swales, soakaways and infiltration trenches, due to their ease of implementation and lower costs. However, topography, soil infiltration and water table levels pose significant challenges. Other SUDS types, such as permeable paving areas, retention/detention ponds, infiltration basins and constructed wetlands were not considered favourably. Potential enablers identified included enhancing the local technical expertise on SUDS, developing adapted guidance documents and policies and the implementation of pilot projects as showcases for SUDS efficacy in managing stormwater. The study has contributed to identifying the most suitable SUDS components for implementation in road projects in Mauritius and pathways to increase their adoption. Full article

When urban underground interchange tunnels pass beneath a water-rich spoil-disposal landfill, water–mud inrush risk is jointly controlled by artificial fill, geological conditions, tunnel-group construction disturbance, and environmental constraints. This study investigates the section beneath the Bujiuwo spoil-disposal landfill in the North Extension Project of Qiaocheng East Road, Shenzhen, and aims to identify key risk factors and reveal their hierarchical transmission mechanism. Based on engineering investigation data, design documents, construction risk sources, and expert questionnaires, an indicator system containing 18 risk factors was established. The decision-making trial and evaluation laboratory method was used to calculate the influence degree, affected degree, centrality, causality, and centrality-derived weight of each factor. Adversarial interpretive structural modeling was then introduced to extract the topological hierarchy and identify key coupling loops. The results show that structural fissure water pressure, vertical clearance, landfill water level, emergency pumping and drainage capacity, and spoil-fill thickness act as key nodes in the DEMATEL risk-relation network. Two key loops were identified: the landfill water level–structural fissure water pressure loop and the vertical clearance–additional stress of tunnel group–damage rate of anti-seepage membrane loop. A hierarchical control strategy is proposed, including source control, channel blockage, construction disturbance control, monitoring, early warning, and emergency management. From a sustainability perspective, the proposed framework supports groundwater protection, pollution prevention, maintenance of landfill containment integrity, and reduction in construction-induced environmental risks. Full article

Interlocking permeable pavements (IPPs) are increasingly adopted within sustainable urban drainage systems to reduce runoff, improve water quality, and strengthen climate-resilient urban infrastructure. However, clogging remains the principal constraint on their long-term hydraulic performance and wider implementation. This review synthesises current evidence on clogging mechanisms, hydraulic decline, and lifecycle mitigation strategies for permeable interlocking concrete pavements (PICPs), concrete grid pavements (CGPs), and plastic grid pavers (PGPs). The literature is dominated by PICP studies, with CGP and PGP underrepresented, restricting typology-specific assessment. Sediment accumulation within joints, grid openings, bedding layers, and near-surface interfaces is consistently identified as the primary clogging mechanism, while traffic, rainfall-runoff loading, biological processes, pollutant retention, and sediment inputs from adjacent impervious surfaces further influence hydraulic deterioration. The findings indicate that hydraulic performance is influenced not only by pavement age but also by interactions among pavement design, filler or joint material, drainage configuration, construction quality, sediment exposure, monitoring, and maintenance. Effective mitigation therefore requires lifecycle management, encompassing source control, pretreatment, appropriate material selection, construction quality assurance, routine hydraulic monitoring, and timely preventive and restorative maintenance. Future research should prioritise standardised clogging assessment protocols, improved laboratory–field integration, targeted investigation of CGP and PGP, biological and pollutant-linked clogging processes, climate-driven rainfall extremes, and decision-support. Full article

Climate change increasingly impacts urban areas, particularly in developing countries. Although some Brazilian cities have advanced climate adaptation policies, these initiatives remain concentrated in a limited number of municipalities. In this context, the objective of this study is to analyze climate adaptation strategies implemented in Spanish cities and evaluate their potential applicability to the Brazilian urban context. The study adopts a qualitative comparative approach combining bibliographic and documentary research, analysis of climate policies, and technical field visits to fourteen Spanish cities. The comparative analysis focused on identifying adaptation measures with the greatest potential for transfer to Brazil while considering differences in governance capacity, financial resources, urban infrastructure, and climatic conditions. The results indicate that climate shelters, sustainable urban drainage systems (SUDS), infiltration gardens, public drinking-water fountains, urban shading structures, and green infrastructure constitute feasible strategies for many Brazilian municipalities. The study concludes that international cooperation and the exchange of successful urban experiences can support the development of more resilient Brazilian cities, provided that adaptation policies are tailored to regional climatic diversity, institutional capacities, and local socioeconomic conditions. Full article

Water security is a prerequisite for achieving the Sustainable Development Goals, yet water insecurity remains a critical challenge in urban slums. This study assesses the water security in the slums of Dhaka City, Bangladesh by integrating multiple dimensions of water security, such as water supply, sanitation and hygiene, water environment, water and climatic risks, and water governance. Suitable indicators and variables are used to capture the key dimensions of water security. A mixed-method approach, incorporating quantitative water quality assessment, waterlogging assessment and household survey, and qualitative focus group discussions, in-depth interviews and key informant interviews, is followed for data collection. The results reveal that the water security index (WSI), on a scale of 5.00, varies from 1.72 for Rajur slum to 3.34 for Nabinagar Housing slum. Among the dimensions, the score varies from 1.86 for water environment to 3.05 for water supply. Thus, there is a wide variation in WSI from slum to slum and in score from dimension to dimension. The study suggests improving drainage, sewerage and household solid waste collection systems, cleaning water bodies, improving drinking water quality, and raising awareness on menstrual hygiene management for enhancing water security in Dhaka’s slums. Full article

Rift Valley fever (RVF) is a climate-sensitive mosquito-borne zoonosis long regarded as a rural, pastoral disease, yet accelerating tropical urbanization and intensifying climate variability may be reshaping its epidemiology at the urban–peri-urban interface. This narrative review examines how global climate change and urban-specific climatic conditions jointly shape RVF virus (RVFV) vector habitats, transmission, and burden in tropical and subtropical cities, synthesizing 51 of 412 English-language records identified by a structured, non-systematic search of PubMed, Scopus, Web of Science, and Google Scholar (2009–2026) and selected for relevance to urban and peri-urban RVF. This research draws on human, livestock, and vector evidence from Sub-Saharan Africa, the Arabian Peninsula, and Indian Ocean islands across epidemic and inter-epidemic periods. The synthesis indicates that impervious surfaces, poor drainage, and open water storage can recreate the water-retaining function of rural dambos, sustaining a year-round larval habitat, and that Culex quinquefasciatus dominance together with peri-urban cattle may form an amplification bridge to humans. Direct evidence remains scarce, anchored by a single peri-urban serosurvey and limited urban slaughterhouse entomology. Critical gaps include urban primary-vector ecology, infection-rate data, urban-heat effects, city-specific exposure studies, and coupled climate–urban burden models. We conclude that RVF is a plausible emerging urban threat warranting proactive inter-epidemic surveillance and integration of RVF into urban planning and One Health systems. Full article

Extreme climate events and rapid urbanization pose severe threats to urban water sustainability and environmental resilience. This study presents a surrogate-assisted hydrological simulation framework designed to support sustainable urban drainage planning and multi-objective scenario exploration. The proposed approach integrates a physics-based hydrodynamic model with a machine learning surrogate (XGBoost) to emulate system responses across diverse design configurations. Under the assumed setup, the framework rapidly evaluates hydrological indicators (peak runoff, flood depth, duration, and extent) alongside microclimatic co-benefits (urban cooling and ventilation) driven by blue-green infrastructure. The surrogate model demonstrates high fidelity $\left(R^2\ge 0.93\right)$, achieving a speedup factor of ${10}^5$ to enable sustainable design screening and trade-off analysis between flood mitigation and urban liveability. Furthermore, post-construction water quality baselines demonstrate the framework’s capacity to incorporate holistic environmental metrics. Overall, this research provides a computationally efficient decision-support tool to advance the Sustainable Development Goals (SDGs)—particularly SDG 11 (Sustainable Cities and Communities) and SDG 13 (Climate Action)—by offering an actionable methodology for climate-resilient grey-green infrastructure planning under data-constrained conditions. Full article

Urban drainage overflows can release a large fraction of event-scale pollutants during the early stage, yet current control remains largely driven by hydraulic signals rather than pollutant-release dynamics. This study created a dissolved organic matter (DOM)-based fluorescence fingerprint method to precisely identify the shift from pollutant flushing to dilution or ongoing input, helping determine the timing of first-flush transitions and potential interception. Fourteen wet-weather overflow events from seven drainage systems in Shanghai and Changzhou were investigated using excitation–emission matrix fluorescence spectroscopy, combined with non-negative matrix factorization, random forest feature screening, principal component analysis, mass–volume (M(V)) curve analysis, and Pettitt change-point detection. Five macro-scale fluorescence fingerprints were resolved, representing protein-like, fulvic-like, and humic-like components. Protein-like fingerprints dominated rapid event-scale variations, while fulvic-like and humic-like fingerprints reflected continuous surface-derived input and stable background contribution, respectively. Peak-shift trajectories revealed three fluorescence-evolution modes: directional red-shift migration, peak-position stability, and weak, non-directional variability, reflecting different source-release dynamics and DOM compositional adjustments during overflow. Random forest screening identified 20 high-importance fine-scale fluorescence fingerprints, with 90% concentrated in protein-like regions linked to sewage-derived and labile DOM. Compared with macro-scale fingerprints and conventional water quality indicators, fine-scale fluorescence fingerprints showed clearer stage separation, stronger consistency with M(V)-based cumulative response patterns, and more distinct first-flush interception timing. This timing marked the transition from early concentrated pollutant release to dilution or sustained input, whereas macro-scale fingerprints indicated broader transition intervals and conventional indicators showed delayed responses. These findings highlight the potential of fine-scale fluorescence fingerprints to support future fluorescence-assisted overflow control by improving transition identification and targeted interception decisions. Full article

Progressive climate change and rapid urbanization are placing increasing pressure on water resources, highlighting the need for local stormwater retention and reuse in residential areas. This study aimed to evaluate the influence of geological-engineering and geotechnical conditions on the design of stormwater management systems and to develop a conceptual solution for a residential property in Kraków, Poland. Geological, hydrogeological, hydrological, and topographic conditions were assessed using archival data verified through field investigations. Rainfall data from the Kraków-Balice meteorological station (2014–2023) were used to estimate rainwater harvesting potential and evaluate system performance. The proposed system consists of surface and subsurface drainage, two storage tanks, and an infiltration well. The first tank collects roof runoff for non-potable domestic use, whereas the second stores water from the drainage system and paved surfaces for irrigation. The annual rainwater harvesting potential was comparable to the non-potable water demand of a five-person household, while water collected from the drainage system and paved surfaces was sufficient for irrigation. Monthly precipitation analysis revealed pronounced seasonal variability, with winter shortages and summer surpluses. Integrating the storage tanks with the infiltration well enabled effective management of excess stormwater while supporting groundwater recharge. The results demonstrate that consideration of geological-engineering conditions is essential for the effective and sustainable design of residential stormwater management systems. Full article

This PRISMA-guided scoping review examines the use of waste materials in civil engineering as a sustainable approach to reducing environmental impacts, conserving natural resources, and supporting circular economy principles. The rapid growth of urbanization, industrialization, mining, and agricultural activities generates large amounts of waste materials, including fly ash, ground granulated blast-furnace slag, bauxite residue, mining tailings, waste rock, acid-mine drainage sludge, waste plastics, post-consumer vulcanized rubber, recycled construction materials, and agricultural ashes. The disposal of these materials often creates serious environmental and land-use problems, making their reuse increasingly important. In this context, civil engineering is one of the most promising sectors for large-scale waste valorization because of its high material demand and its ability to use different waste streams into practical applications such as concrete and cementitious systems, pavement and asphalt engineering, geotechnical works, and other infrastructure sectors. This review critically evaluates the global availability, material characteristics, engineering applications, environmental and economic benefits, recent advances, and key challenges related to major industrial, mining, agricultural, polymeric, and construction-derived wastes. Although significant progress has been made in this field, wider implementation is still limited by variations in material properties, technical and environmental challenges, economic constraints, and limited field validation of long-term performance. By bringing together current knowledge from different waste streams and civil engineering sectors, this review highlights important research gaps and future directions to support more sustainable, resilient, and resource-efficient infrastructure development. The effective use of waste materials in civil engineering can play an important role in reducing carbon emissions, improving resource efficiency, and supporting global sustainability. Full article

Urban combined sewer systems are increasingly challenged by climate-intensified rainfall, combined sewer overflows, and receiving-water degradation. This study presents a retrospective evaluation of a hybrid green-gray retrofit program implemented in the Zhenjiang Sponge City pilot watershed, China, where green stormwater infrastructure, drainage network upgrades, and a centralized deep tunnel system were integrated within a densely developed watershed constrained by limited space, low native-soil permeability, shallow groundwater, and aging infrastructure. System performance was evaluated using long-term operational observations, representative hydraulic and water-quality monitoring, municipal operational records, and supporting engineering analyses at both facility and watershed scales. The results demonstrated sustained hydraulic functionality after 7–10 years of operation, with approximately 90% of the monitored bioretention systems maintaining effective infiltration rates greater than 80 mm h⁻¹. Event-based monitoring indicated substantial reductions in runoff volume and pollutant loads, including TSS, COD, NH₃–N, and TP. Following implementation, annual combined sewer overflow occurrence at major outfalls decreased from 318 to 24 events, representing a 92.5% reduction. Supporting engineering analyses indicated that green stormwater infrastructure retrofits alone reduced overflow frequency by approximately 41.8% and overflow volume by approximately 61.1%, while integration with deep tunnels increased reductions to approximately 58.8% and 85.3%, respectively. Official receiving-water monitoring records further indicated that Class III or better water-quality conditions were maintained during approximately 74.7% of the monitored days between 2021 and 2026. These findings provide long-term watershed-scale evidence that hybrid green-gray retrofit strategies can integrate green stormwater infrastructure with centralized overflow regulation to achieve sustained overflow reduction and receiving-water improvement in highly constrained urban watersheds. Full article

Pesticide contamination in urban runoff, stormwater, and peri-urban drainage networks is an increasing concern because of the persistence, mobility, and ecological toxicity of many pesticide residues and their transformation products. Nature-based solutions (NBSs), including constructed wetlands, bioretention systems, biofilters, and permeable reactive bio-barriers, provide low-energy and ecologically compatible platforms for urban water treatment; however, their performance is often constrained by limited sorption capacity, substrate saturation, variable hydraulic loading, and incomplete degradation of persistent pesticides. Biochar offers a multifunctional amendment for strengthening these systems because its tunable porosity, surface functionality, mineral composition, redox activity, and microbial habitat-forming capacity can support pesticide adsorption, catalytic transformation, and biodegradation. This review critically evaluates biochar-integrated NBSs for pesticide-contaminated urban water systems by linking biochar production and modification strategies with pesticide removal mechanisms, biochar–microbe interactions, engineered treatment configurations, and field-scale applicability. A comparative synthesis is provided across material-level mechanisms, system-level performance, machine learning-assisted prediction, techno-economic feasibility, life-cycle impacts, and environmental risk considerations. By integrating material properties, removal mechanisms, NBS configurations, predictive modeling, sustainability assessment, and risk considerations, this review provides a broader comparative basis than previous studies focused mainly on individual aspects of biochar-based pesticide remediation. Future priorities include standardized biochar production, long-term field validation, spent-biochar management, ecotoxicological assessment, and data-driven optimization of biochar-assisted NBSs. Full article

Flash flood events are among the most critical hydrological hazards in arid and semi-arid regions, posing extreme threats to critical infrastructure, human safety, and sustainable development plans. This paper evaluates the flash flood susceptibility of the Al’Ataya catchment, a key watershed on the southern Red Sea coast, using an integrated geospatial analysis approach. To assess and quantify the flood hazard, we investigated 15 morphometric parameters for 24 particular sub-catchments within a sixth-order drainage system. Two complementary methods, the Morphometric Ranking Method and El-Shamy’s approach, were utilized to classify the catchment into different flood susceptibility levels. Results from the Ranking Method identified seven sub-catchments (SC-2, SC-3, SC-6, SC-7, SC-8, SC-9, and SC-19) as having high flood hazard levels, mainly driven by large watershed areas, steep slopes, and high relief ratios. In contrast, El-Shamy’s approach resulted in a different evaluation, identifying sub-catchments in Zone B (SC-23, SC-16, SC-17, SC-15, SC-6, SC-20) as high hazard sub-catchments due to the particular relationship between the bifurcation ratio parameter and the drainage density and stream frequency parameters. The integration of the two methods suggests that the susceptibility factor is controlled by the combined influence of a low drainage density and steep mountainous terrain draining toward the coastal zone. These results provide a spatial model for flood mitigation and early warning systems, supporting Saudi Vision 2030 through improvement to the development of southern urban centers such as Al’Ataya and Sabya. Full article

In order to improve the assessment of the dynamic risk of urban waterlogging, this study addresses the limitations of existing methods in capturing the responses of surface roads and subway systems to inundation, as well as the resulting spatiotemporal risks. Using the Hanyang District in Wuhan as a case study, the research proposes a framework for assessing urban waterlogging risks based on the dynamic inundation responses of surface and underground transport systems under various rainfall scenarios. The waterlogging process is simulated using seven representative rainfall scenarios with a hydrodynamic model that integrates a one-dimensional pipe network, a two-dimensional surface overland flow model, and a generalized underground space model. A coupled road–subway transportation network is developed to analyze traffic capacity degradation, path redistribution, and cascading failures caused by waterlogging disturbances. Quantified dynamic response indicators are integrated into the H-E-V-C framework to assess dynamic urban waterlogging risk. The results indicate that direct failure caused by water accumulation is typically the primary catalyst for extensive degradation of the transportation network, while the expansion of congestion and localized overload failures further exacerbate cascading effects. Different rainfall patterns influence not only peak risk but also the duration and spatial development of high-risk areas. Incorporating the dynamic response of the transport system enables a more accurate assessment of the degradation of emergency accessibility and the ongoing accumulation of localized high-risk areas. These findings highlight the importance of dynamic risk assessment in identifying time-varying urban vulnerabilities and supporting the planning of sustainable urban drainage, traffic management, and phased early warning systems. Full article