Search Results (162)

Mediterranean agriculture is increasingly constrained by severe and recurrent water scarcity. Rising temperatures, declining precipitation, and more frequent droughts are driving higher crop water demand and reducing rainfall reliability. Combined with growing competition for limited freshwater resources, these climatic pressures pose a major challenge to the long-term sustainability and productivity of farming systems in the region. In this context, urban treated wastewater (UTWW) is increasingly recognized as a strategic alternative resource. Regulation (EU) 2020/741 establishes minimum quality requirements for agricultural water reuse based on the fit-for-purpose principle. The Italian regulatory framework requires regional authorities to plan water reuse by mapping reclamation facilities, water demand, and distribution networks. From this perspective, to support the planning process, this study describes the application of a Geographic Information System (GIS)-based methodology to assess the potential for UTWW reuse in Sicily by integrating national datasets (regularly updated) and comparing reclaimed water supply with irrigation demand from both qualitative and quantitative perspectives. UTWW supply was estimated by integrating data from the Italian National Institute of Statistics (ISTAT) Census of Water for Civil Use and the European Environment Agency (EEA) dataset, while irrigation demand was derived by combining Copernicus crop data, ISTAT irrigated-to-total UAA ratios and crop-specific irrigation demand (Seasonal Specific Volumes) derived from the SIGRIAN database. Two scenarios were analyzed for grasslands, vineyards, olive groves, and orchards. Scenario 1 included only wastewater treatment plants (WWTPs) located inside irrigation areas, whereas Scenario 2 also included selected WWTPs located outside irrigation areas where orographic and distance constraints allowed potentially feasible connections. Under Regulation (EU) 2020/741, potential compatibility with the required water quality classes was identified at the screening level for all crop categories considered, which require classes B, C or D. From a quantitative perspective, Scenario 1 identified 19 WWTPs serving 11 out of 38 irrigation areas with an aggregated uncapped demand coverage of 53%; only two areas reached full local demand satisfaction. Scenario 2 added 23 external WWTPs, increased potentially served areas to 20, and raised the aggregate uncapped coverage to 73%. When surplus volumes were capped within each irrigation area, effective demand satisfaction was 12% and 22% in Scenarios 1 and 2, respectively, highlighting the importance of storage, conveyance and inter-area transfer. The results indicate that treated wastewater reuse could contribute to agricultural water security and climate-resilient water management in Mediterranean regions. The framework supports the first-order identification of candidate reuse areas, but site-specific assessments of effluent quality, risk management, costs, and seasonal storage remain necessary before implementation. Full article

Population growth, increasing water demands for data centers, and the need for more sustainable water practices are prompting advancement of next-generation water resource management strategies including water reuse. In the Midwestern United States (U.S.), where non-traditional approaches to augmenting water supply, including water reuse, are relatively new, full advanced water treatment (AWT), which includes microfiltration/ultrafiltration (MF/UF) and reverse osmosis (RO), produces a concentrate stream that is expensive to address (i.e., brine disposal). Carbon-based advanced treatment (CBAT), which combines ozonation, biofiltration, and granular activated carbon, has been shown to be a viable alternative with select advantages over the traditional RO approach, including the lack of brine generation. Two novel pilots were conducted in the Midwestern U.S., one at a large (>100 MGD) and one at a small (~10 MGD) wastewater reclamation facility (WRF), to provide proof of concept that CBAT could meet distinct regional needs. While additional demonstration data are ultimately needed for future regulatory approvals, results from the pilots showed that water quality objectives were met with treated water quality of <0.5 mg/L total Kjeldal nitrogen (TKN), <2 mg/L total organic carbon (TOC), and substantial reduction in constituents of emerging concern (CECs). If nitrate removal is required to meet drinking water standards (10 mg/L), additional treatment optimization at the source WRFs would be required. Areas for further research identified by this effort include mitigating the potential for ozonation to contribute to the formation of disinfection byproducts such as bromate and N-nitrosodimethylamine (NDMA). Along with the treatment performance demonstrated at these pilots, the study provided an opportunity to engage with key stakeholders to build trust in the AWT approach, which is critically important for regulatory and public acceptance. Based on two field-scale pilot studies in the U.S. Midwest, this paper analyzes CBAT application advantages and challenges in municipal water reuse and identifies research directions for the industry. Full article

This study presents the results of long-term field experiments investigating the effects of subsurface heating and irrigation with discharged warm water (28–35 °C) on the hydrothermal, redox, biological, and salt regimes of Haplic Chernozem (Loamic, Endocalcaric) in the central Forest-Steppe zone of Ukraine. The experiments were conducted under contrasting hydro-meteorological conditions, allowing assessment of thermo-reclamation practices across a wide range of temperature and soil moisture regimes. Subsurface heating increased soil temperature by 7.3–11.1 °C at the depth of heating pipe installation, while the thermal effect gradually decreased with increasing distance from the heat source. Combined heating and irrigation created a more uniform temperature distribution within the root zone, reduced the depth and duration of soil freezing, and improved hydrothermal conditions throughout the growing season. The studied soils maintained predominantly oxidative conditions under all treatments. However, the combined application of heating and irrigation promoted a more homogeneous distribution and seasonal stabilization of soil redox potential throughout the profile. Soil heating also enhanced microbiological activity, thereby increasing cellulolytic activity, particularly during cold and dry periods when soil temperature and moisture limited microbial processes. Irrigation with slightly mineralized warm wastewater did not cause significant overall soil salinization but resulted in the redistribution of calcium and sodium within the soil profile. Subsurface heating intensified the seasonal dynamics of readily soluble salts, promoting their temporary accumulation near the heating pipes, whereas combined heating and irrigation facilitated subsequent leaching of excess salts into deeper horizons. The integrated application of subsurface heating and irrigation produced the highest and most stable perennial grass productivity, increasing biomass yield by 87–163% compared with the control, irrespective of meteorological conditions. These findings demonstrate that the integrated use of industrial waste heat for subsurface heating combined with irrigation represents a promising and environmentally sustainable thermo-reclamation technology capable of improving soil functioning and agricultural productivity, provided that long-term monitoring of soil water–salt regimes is maintained. Full article

Increasing water scarcity and pollution have intensified the need for low-cost wastewater treatment in developing regions. Constructed wetlands (CWs) offer a nature-based solution for pollutant removal but often fail, on their own, to meet discharge and reuse standards. This study evaluated four CW systems planted with Cyperus latifolius, Juncus effusus, Phragmites mauritianus, and Pennisetum purpureum, integrated with banana fibre filtration as a polishing step. The CWs alone achieved ammonium removal of 74–83%, nitrate 78–85%, phosphorus 86–91%, and COD 78–83%. Banana fibre filtration enhanced overall removal efficiencies to 93–96%, 94–96%, 81–88%, and 82–87% for ammonium, phosphorus, nitrate, and COD, respectively. Pennisetum purpureum had the highest aboveground nitrogen accumulation (74.4 g N/m²), with its coupled system achieving the highest nitrate removal, whereas Juncus effusus had the highest phosphorus accumulation (93.1 g P/m²), with its coupled system showing the best overall removal of ammonium, phosphorus, and COD. The integrated system reduced fecal coliforms and Escherichia coli by 6–8 log and eliminated detectable Salmonella and Shigella. Treated effluent met FAO irrigation, Rwanda discharge, and European Union (EU) standards for all evaluated parameters except phosphorus, which remained above the stricter EU limit. Despite bench-scale operation over four months, these findings demonstrate a low-cost, nature-based treatment approach suitable for decentralized wastewater treatment and reuse, with harvested wetland biomass offering additional potential for animal feed, energy, or fibre valorization. Full article

Population growth, climate change, pollution, and prolonged droughts are contributing to increasing water scarcity, which poses a significant challenge to global sustainable water management. Among the available adaptation strategies, potable water reuse has emerged as a viable and increasingly adopted solution in areas facing water stress. This review examines evolution, regulatory frameworks, treatment technologies, and implementation strategies related to drinking water reuse worldwide. Through the historical review, it becomes clear that the idea of water reuse has deep roots (5000 years ago), while the analysis of modern legislative and intergovernmental approaches led to the conclusion that the rules governing water reuse vary depending on the country and are in most cases quite strict (e.g., the Urban Wastewater Treatment Directive (UWWTD) and the Water Framework Directive). To make potable water reuse possible, including direct and indirect systems, advanced wastewater treatment technologies are applied, among which membrane processes and advanced oxidation processes (AOPs) are most often chosen, while treatment trains are almost always used. The recent studies of potable water reuse presented highlight the interest of both the scientific community and the state. The economic review demonstrates that potable water reuse can be economically viable and more economical than other solutions, e.g., desalination. The review identifies the key challenges (technical, economic, institutional, and social) and opportunities for scaling up potable water reuse as a primary water supply option and discusses its potential role in enhancing long-term sustainable water management, especially in areas that are either arid or semi-arid. Full article

Reusing wastewater in agriculture is essential due to water scarcity but requires treatment technologies that preserve soil biological integrity. This study evaluated the impact of irrigation with wastewater treated by cold atmospheric plasma (CAP; 60 min exposure) on the soil microbiome during Festuca rubra L. and Sinapis alba L. cultivation. The experimental design included various CAP-wastewater dilutions evaluated in two replicates (n = 2), with microbial shifts assessed via 16S rRNA gene sequencing. CAP treatment reduced non-purgeable organic carbon (NPOC) while enriching the water with nitrogen, which significantly stimulated S. alba root growth. Metagenomic analysis confirmed high microbiome stability. Dominant phyla (Proteobacteria and Actinobacteriota) remained stable, and beta-diversity indices showed no statistically significant ecological shifts (R² = 0.420, p = 0.121). Furthermore, CAP-treated irrigation promoted beneficial taxa, specifically the genus Bacillus. These findings demonstrate that CAP wastewater treatment is a safe, environmentally responsible strategy for wastewater reclamation. It successfully supports nutrient cycling and agricultural production without compromising soil microbial homeostasis or health, offering a viable solution aligned with the principles of a circular economy. Full article

Microplastics have recently emerged as a widespread contaminant in wastewater, posing severe risks to the environment and human health due to their potential bioaccumulation and toxicity. Conventional wastewater treatment processes are generally inadequate for the complete removal of microplastics due to their modest scale. Interest has been garnered from academia and industry regarding their separation from wastewater. This review covers recent advances in the application of membrane processes for the removal of microplastics from wastewater. The principles of membrane separation, removal efficiency, and operational challenges are critically evaluated, along with the potential of the hybrid membrane systems. In the next section, the fouling mechanism induced by microplastics and their interaction with foulants, as well as cleaning and anti-fouling strategies, are discussed. Finally, future perspectives focus on the current unresolved research gaps, including the integration of digital monitoring and artificial intelligence-assisted optimization of membrane technology for microplastic removal. By consolidating current knowledge and identifying pathways for innovation, this review underscores the pivotal role of membranes in mitigating plastic pollution and advancing sustainable wastewater management. Full article

Agricultural pesticide wastewater represents a significant environmental and public health challenge, highlighting the need for scalable and resource-efficient treatment strategies. This review adopted a PRISMA-based methodology using the Scopus and Web of Science databases, leading to the analysis of 176 peer-reviewed studies published between 2014 and 2025. The selected literature was critically examined to assess pesticide wastewater treatment technologies, including adsorption, membrane filtration (MF), advanced oxidation processes (AOPs), biological treatments, and hybrid configurations. Particular attention was given to their treatment performance, scalability from farm to district level, resource recovery potential, economic feasibility, and life-cycle assessment (LCA) implications. Among the evaluated systems, hybrid configurations combining biological processes with AOPs or MF generally showed higher removal performance, often achieving more than 80% pesticide residue removal, while offering greater adaptability and compatibility with circular biorefinery frameworks. The review identifies key opportunities for resource recovery, including methane and hydrogen production, nutrient recycling, water reuse, and chemical reclamation, thereby supporting circular bioeconomy objectives. Overall, this review proposes an integrated, multiscale circular biorefinery perspective for sustainable pesticide wastewater management and identifies research priorities for developing resilient, safe, and resource-efficient agricultural water treatment systems. Full article

Wastewater is a complex and dynamic issue, particularly at the human–animal–environment interface, bearing biological and chemical hazards that may serve as a resource for transmission pathways for pathogens, antimicrobial resistance (AMR) determinants, heavy metals, pharmaceutical residues, per- and polyfluoroalkyl substances (PFAS), and microplastics. Rising global health issues necessitate effective wastewater treatment and advanced research to support risk-informed circular management within a one health framework, incorporating wastewater-based epidemiology (WBE), multi-omics approaches, nanobiotechnology, and green technologies. Inadequate wastewater treatment and uncontrolled discharge result in the generation of more than 380 billion cubic meters of wastewater annually worldwide, contributing to ecological degradation, the spread of AMR, and long-term toxicological risks. Despite significant advances in wastewater treatment, several challenges remain, including complex contaminant mixtures, limited detection and monitoring technologies, variable treatment efficiency, and weak regulatory and governance frameworks. This review highlights key wastewater treatment issues and presents recent advances in WBE and multi-omics approaches, such as metagenomics, resistome profiling, virome analysis, and chemical fingerprinting for contaminant monitoring and public health risk assessment. This review also examines circular reuse strategies focused on water reclamation, nutrient recovery, bioenergy production, and resource recovery, with particular emphasis on nature-based systems, hybrid biological–physicochemical treatment platforms, and green nanobiotechnology as promising approaches to improve treatment performance while minimizing environmental impacts. In conclusion, this review highlights the importance of integrated and sustainable wastewater management approaches within the One Health framework to address emerging challenges and promote environmental resilience, public health protection, and circular resource recovery. Full article

The use of treated wastewater constitutes a strategic alternative for agriculture in water-scarce regions. This study developed and applied a distance-based and sodium-constrained deterministic allocation model integrating geoprocessing tools with environmental and logistical constraints to optimize the spatial distribution of treated effluent from 48 wastewater treatment plants (WWTPs) in the semi-arid region of Minas Gerais, Brazil. The deterministic allocation algorithm prioritizes geographic proximity and favorable topographic differences as a proxy for reducing potential pumping requirements. Two scenarios were evaluated: (1) full effluent availability and (2) sodium-regulated allocation limited to 300 kg ha⁻¹ year⁻¹ of Na, in accordance with Normative Deliberation CERH-MG 65/2020. Under Scenario 1, cotton demand exceeded (184%), while coffee and sugarcane reached 69% and 24% of annual demand, respectively. Under the sodium-constrained Scenario 2, demand fulfillment changed to 37% for coffee and 42% for sugarcane, while cotton remained above full demand (108%). The proposed model differs from previous deterministic spatial allocation applications by integrating regulatory sodium constraints and dual-scenario regional assessment, providing a spatially explicit and regulation-compliant decision-support tool for sustainable wastewater reuse in semi-arid agricultural systems. Full article

Background: Wastewater treatment plants (WWTPs) are hotspots of antimicrobial resistance (AMR) due to inputs from diverse anthropogenic sources. Aeromonas spp., ubiquitous in aquatic environments, often carry clinically relevant antibiotic resistance genes (ARGs) and can persist beyond fecal contamination indicators, making them promising sentinel organisms for AMR dissemination. The aim of this study was to assess the suitability of Aeromonas spp. in this role by characterizing resistance profiles, associated virulence factor genes (VFGs), genetic mobility, and persistence across wastewater and drinking water treatment processes in the Barcelona metropolitan area, Spain. Methods: Isolates were phenotypically characterized and screened for ARGs, VFGs, integrons, and heavy metal tolerance genes, followed by whole-genome sequencing (WGS). Biofilm formation was assessed in vitro. Conjugation assays with Escherichia coli evaluated horizontal gene transfer (HGT) potential. Results: A total of 428 antibiotic-resistant Aeromonas spp., the most abundant antibiotic-resistant bacteria isolated during the 2023 sampling campaigns from two WWTPs and one drinking water treatment plant (DWTP), were characterized. Trimethoprim/sulfamethoxazole (SXT) non-susceptibility was most frequent (72%), followed by cefoxitin resistance (65.4%). The sul1 (57.5%) and bla_MOX (78.6%) genes predominated among SXT- and β-lactam-resistant isolates. The merA gene was detected in 23.6%; 97.9% harbored at least one VFG (aerA, act, fla, alt, or hlyA), and 70.3% carried intI1. Half formed biofilm. Conjugation confirmed bi-directional HGT, and WGS revealed persistent ST3458 clones across treatment stages. Conclusions: WWTPs and DWTPs act as reservoirs of antibiotic-resistant Aeromonas spp., demonstrating persistence and HGT potential. Findings support their use as sentinel organisms for AMR surveillance in aquatic environments and for assessing treatment efficacy, highlighting variability across treatment types and locations, and reinforcing their relevance for urban water reclamation monitoring. Full article

Aerobic granular sludge (AGS) represents a promising alternative to the conventional activated sludge process for wastewater treatment, owing to its advantages in reducing land area requirements, operational costs, and carbon footprint. With the increasing global implementation of full-scale AGS systems, recent studies have increasingly concentrated on the recovery of valuable resources from waste AGS. AGS is an effective carrier for a variety of valuable substances, including alginate-like exopolymers, polyhydroxyalkanoates, phosphorus, tryptophan, xanthan, curdlan, and cellulose. This study seeks to offer a thorough review of the recovery potential, extraction methodologies and current state of knowledge regarding each of these materials. To improve economic viability, future studies should focus on developing strategies for the sequential recovery of multiple resources from AGS. Furthermore, integrating AGS with other emerging technologies, such as microalgal treatment and a partial nitritation/anammox process, may enhance the reclamation of organic carbon from wastewater. Full article

Growing wastewater volumes and intensifying water scarcity are driving the need for affordable, sustainable solutions that enable safe urban water reuse and strengthen climate resilience. Policy frameworks such as SDG6 and EU water reuse requirements highlight that reclaimed water must meet strict environmental and public health standards. In contrast, conventional biological treatment cannot fully remove many emerging contaminants, underscoring the need for advanced treatment approaches that consistently deliver high-quality reclaimed water. In this context, this review examines the role of membrane technologies (MF, UF, NF, RO, FO) and membrane bioreactors (MBRs) in providing safe water in urban environments and in enhancing urban climate resilience, including decentralized systems and advanced reclamation needs. It also discusses the contribution of membrane-based solutions to sustainable cooling systems and heat-stress mitigation, as well as the integration of membrane technologies into green infrastructure and nature-based solutions for climate adaptation. Technical and economic performance is shaped by fouling, cleaning requirements, and energy use, making life-cycle and operational optimization critical for long-term sustainability. Case studies and EU-funded initiatives demonstrate that, with appropriate governance and design, membrane-based approaches can enable reliable reclaimed water supply, enhance water security, and contribute to circular urban water management. The analysis was based on peer-reviewed open-access publications, which may introduce a degree of selection bias. Full article

Changes in land use and land cover (LULC) are crucial indicators to consider when examining various environmental challenges and assessing the sustainability of rapidly transforming landscapes. Land utilization in arid regions results from a diverse range of socioeconomic activities that reshape urban and regional environments. Using remote sensing and geographic information systems (GISs), the authors investigate the evolving and sustainability-sensitive landscape of the Al-Kawamel area, southwest of Sohag City, Egypt. Three time series of Landsat imagery, from 1985, 2005, and 2025, were used to map major LULC categories and evaluate their transformations with respect to elevation and slope. Based on the data analysis, the results reveal substantial shifts over the 40-year period in this low desert zone. During this time, the built-up areas and the agricultural lands expanded from 8 to 64 km² and from 10 to 131 km², respectively. Conversely, the desert zone declined from 325 to 148 km². These essential changes reflect intensified human activities and land reclamation. These rapid shifts increase exposure to natural and man-made hazards, including karstification, sand accumulations, rockfalls, flash floods, problematic soils, heavy metal hazards from wastewater disposal sites, and abandoned pits. Accordingly, suitable remediation methods should be assigned to minimize their impact. Full article