Search Results (282)

Rainwater harvesting for sustainable agriculture (RWHSA) offers a viable and eco-friendly strategy to alleviate water scarcity in semi-arid regions, particularly for agricultural use. This study aims to identify optimal sites for implementing RWH systems in northern Iraq to enhance water availability and promote sustainable farming practices. An integrated geospatial approach was adopted, combining Remote Sensing (RS), Geographic Information Systems (GIS), and Multi-Criteria Decision Analysis (MCDA). Key thematic layers, including soil type, land use/land cover, slope, and drainage density were processed in a GIS environment to model runoff potential. The Soil Conservation Service Curve Number (SCS-CN) method was used to estimate surface runoff. Criteria were weighted using the Analytical Hierarchy Process (AHP), enabling a structured and consistent evaluation of site suitability. The resulting suitability map classifies the region into four categories: very high suitability (10.2%), high (26.6%), moderate (40.4%), and low (22.8%). The integration of RS, GIS, AHP, and MCDA proved effective for strategic RWH site selection, supporting cost-efficient, sustainable, and data-driven agricultural planning in water-stressed environments. Full article

Rainwater harvesting (abbreviation: RWH) presents a valuable alternative water source for agriculture, particularly in regions facing water scarcity. However, contaminants leaching from roofing materials, such as asbestos cement (abbreviation: AC), may compromise water quality and affect plant physiological responses. This paper aimed to assess how simulated rainwater, reflecting the different levels of contamination (1, 2, 5, 10, and 20 mg/L), influences leaf temperature in tomato plants (Solanum lycopersicum), a known non-invasive indicator of plant water stress. The treatments were applied over a four-week period under controlled greenhouse conditions. Leaf temperature was monitored using infrared thermography. Results showed that higher treatment concentrations led to a significant increase in leaf temperature, indicating elevated water stress. These findings suggest that even low levels of contaminants originating from roofing materials can induce detectable physiological stress in plants. Monitoring leaf temperature offers a rapid and non-destructive method for assessing environmental water quality impacts on crops. The outcomes of this research have direct applicability in the safer design of RWH systems and in evaluating the suitability of collected rainwater for irrigation use. Full article

Water scarcity is a critical issue exacerbated by climate change, urbanization, and population growth, particularly in regions with insufficient water infrastructure. Rainwater harvesting (RWH) systems offer a sustainable solution to mitigate water shortages by collecting and storing rainwater for non-potable uses. This study focuses on the design, efficiency, and reliability of RWH systems in residential environments, with an emphasis on optimizing the sizing of storage volumes and collection areas. Using a behavioural simulation model, we generate nomograms that facilitate the design of RWH systems by analyzing the interactions among storage capacity, collection area, rainfall patterns, and water demand. Specifically, this paper evaluates the effectiveness of RWH systems through efficiency and reliability metrics such as water savings, mains reliance, overflow discharge, and system reliability. The proposed procedure integrates stochastic rainfall and water demand data, including a detailed analysis of toilet usage, in order to simulate the performance of RWH systems across different time scales. Case studies in Italy and Denmark are used to assess the influence of climatic differences on system performance. The findings provide a comprehensive methodology for RWH system design, and offer valuable insights into improving a sustainable water management strategy. Full article

The objective of this research was to assess the first flush of rainwater harvested from a fibre–cement roof in southern Brazil. Runoff samples were collected for quantifying pH, total suspended solids, turbidity, conductivity, apparent colour, total coliforms, and Escherichia coli. Statistical methods were employed to describe the data, establish correlations between variables, and assess if the antecedent dry weather periods and rainfall intensity affected water quality. The qualitative characterisation of the first flush was performed using principal component analysis and simple regression analyses. The results show that rainwater runoff can be highly contaminated. Hypothesis tests showed that initial rainfall intensity and antecedent dry weather periods affect the quality of the first flush. Principal component analysis suggested that the most significant variables to characterise the first flush were turbidity and apparent colour. Using first-flush diverters in rainwater harvesting systems does not ensure E. coli removal, but it may reduce the risk of users’ contamination. Practical implications include discussions on the suggested first flush and the consequential impact on the quantity and quality of rainwater harvested. Future studies may consider using the method used in this research to develop guidelines based on more samples across the country. As novelty, one includes a statistically robust qualitative study in a region that lacks research on the quantification and quality of first flush. Such assessment helps to build up Brazilian data for a better understanding of first flush management in rainwater harvesting. Full article

This study aims to assess the impacts of climate change on the tourism potential of Northeastern Brazil by analyzing historical trends and future climate projections, identifying climate risks, and proposing spatially targeted adaptation strategies. Historical daily climate data from the BR-DWGD and future projections from the MPI-ESM1-2-LR model under the SSP2 4.5 scenario were used to evaluate extremes in temperature and precipitation. Principal component analysis and spatial cluster analysis were applied to identify five climatically homogeneous zones across the region. Results indicate generalized warming trends and intensifying rainfall extremes, particularly in coastal clusters where tourism infrastructure is concentrated. Inland zones, especially those with semi-arid climates, exhibit rising temperatures, prolonged droughts, and increasing water scarcity. These differentiated climatic patterns pose risks to infrastructure, ecosystem services, and the overall sustainability of tourism. In response, the study proposes adaptation measures tailored to each zone, including improved drainage systems, sustainable cooling technologies, rainwater harvesting, and diversification of tourism activities. Emphasis is placed on community-based governance to enhance social equity and resilience. The findings highlight the relevance of spatialized climate analysis for guiding adaptation planning and supporting a more inclusive and climate-resilient tourism sector in the region. Full article

Urban water management faces growing pressure from population growth, pollution, and climate variability, demanding innovative strategies to ensure long-term sustainability. This study applies the Life Cycle Sustainability Assessment (LCSA) across four case studies in Brazil and Germany, evaluating integrated systems that combine constructed wetlands for greywater treatment with rainwater harvesting for non-potable use. The scenarios include a single-family household, a high-rise residential building, a rural residence, and worker housing. A multi-criteria analysis was conducted to derive consolidated sustainability indicators, and sensitivity analysis explored the influence of dimension weighting. Results showed that water reuse scenarios consistently outperformed conventional counterparts across environmental, economic, and social dimensions. Life Cycle Assessment (LCA) revealed notable reductions in global warming potential, terrestrial acidification, and eutrophication. Life Cycle Costing (LCC) confirmed financial feasibility when externalities were considered, especially in large-scale systems. Social Life Cycle Assessment (S-LCA) highlighted the perceived benefits in terms of health, safety, and sustainability engagement. Integrated water reuse systems achieved overall sustainability scores up to 4.8 times higher than their baseline equivalents. These findings underscore the effectiveness of decentralized water reuse as a complementary and robust alternative to conventional supply and treatment models, supporting climate resilience and sustainable development goals. Full article

Water stress is a significant issue in many countries, including Portugal, which has seen a 20% reduction in water availability over the last 20 years, with a further 10–25% reduction expected by the end of the century. To address potable water consumption, this study aims to identify the optimal rainwater harvesting (RWH) system for a commercial building under various non-potable water use scenarios. This research involved qualitative and quantitative methods, utilizing the Rippl method for storage reservoir sizing and ETA 0701 version 11 guidelines. Various scenarios of non-potable water use were considered, including their budgets and economic feasibility. The best scenario was determined through cash flow analysis, considering the initial investment (RWH construction), income (water bill savings), and expenses (energy costs from hydraulic pumps), and evaluating the net present value (NPV), payback period (PB), and internal rate of return (IRR). The energy savings obtained were calculated by sizing a hybrid system with an RWH system and a photovoltaic (PV) system to supply the energy needs of each of the proposed scenarios and the water pump, making the system independent of the electricity grid. The results show that the best scenario resulted in energy savings of 92.11% for a 7-month period of regularization. These results also demonstrate the possibility for reducing potable water consumption in non-essential situations supported by renewable energy systems, thus helping to mitigate water stress while simultaneously reducing dependence on the grid. Full article

This study aimed to assess the impact of climatic alteration on food security in Saudi Arabia. Date productivity, temperature, and precipitation represent the data which were collected from various sources linked to the study subject and cover the period from 1980 to 2023. The Engle–Granger two-step procedure, the VECM, and forecast analysis were applied to test the long-term relationship, short-term integration, and forecasting, respectively. Moreover, qualitative analysis was used to reveal the influence of climatic change on food security. The results discovered long-term co-integration between date productivity and temperature. Additionally, the results revealed that there has been long-running co-integration between date productivity and the precipitation series. Temperature and precipitation negatively and significantly impacted date productivity during the study period. With reference to forecast results, the graph was validated using various forecast indicators: the Alpha, Gamma, Beta, and Mean Square Error equivalents were 1.0, 0.0, 0.0, and 5.47, respectively. Moreover, the growth rates of date productivity were equal to 0.82 and 0.08 for the periods from 1980 to 2022 and 2023 to 2034 (forecast), respectively, indicating that there is a decrease in the growth rate of date productivity (0.08) during the forecast period. From these results, the conclusion is that climatic change (temperature and precipitation) negatively impacts date productivity. In addition, the growth rate during the forecast period decreased, indicating that climatic change is affecting food security currently and will continue to do so in the future. This study recommended specific policy interventions and innovations in agricultural practices, including developing and implementing a national framework focused on climate-smart agriculture, balancing productivity, adaptation, and mitigation. This could be aligned with Vision 2030 and the Saudi Green Initiative. Additionally, this could include investing in research and development by increasing public–private partnerships to support agricultural R&D in arid regions, with a focus on heat- and drought-resistant crop varieties and water-efficient farming systems. Regarding agricultural innovations, these could include the use of renewable energy, particularly solar energy, the expansion of rainwater harvesting infrastructure, recycling treated wastewater for agriculture, and reducing reliance on groundwater sources. Full article

The present review article aims to address what is currently being studied in the field of identifying suitable regions for the implementation of rainwater harvesting (RWH) systems in arid zones. The need for this study is supported by the growing interest in the topic, which has arisen due to growing environmental concerns and the search for sustainable development techniques. Through the application of Methodi Ordinatio, 37 articles produced between 2020 and 2025 were identified. Analyzing the results, it was possible to observe the widespread use of the analytical hierarchy process (AHP) as a Multi-Criteria Analysis (MCA) methodology. To a lesser extent, the Fuzzy Analytic Hierarchy Process (FAHP) and the Weighted Linear Combination (WLC) were also used. The selected thematic layers, as well as the weights for the criteria, underwent a sensitive analysis by the researchers and may exhibit significant variation, even in studies conducted in nearby areas. The most commonly used thematic layers were slope (35 articles), land use/land cover (LULC) (28 articles), rainfall (26 articles), drainage (25 articles), and soil (25 articles). This study can be used as a methodological guide for future research and is important for the systematization of RWH studies in arid zones. Full article

This study employed the HYDRUS-2D model to simulate soil water movement and water productivity (WP) in an apple–soybean alley cropping system in the Loess Plateau region, Shanxi Province, China, under four irrigation methods: mulched drip irrigation, subsurface drip irrigation, bubbler irrigation, and rainwater-harvesting ditch irrigation, with varying water management treatments. Field experiments provided 2022 data for model calibration and 2023 data for validation using soil water content (SWC) measurements, achieving R² = 0.80–0.87 and RMSE = 0.011–0.017 cm³·cm⁻³, confirming robust simulation accuracy. The simulation results indicated that different irrigation methods had a significant impact on the soil water distribution. Mulched drip irrigation enhanced the water content in the surface layer (0–20 cm), while subsurface drip irrigation increased the moisture in the middle soil layer (20–40 cm). Bubbler irrigation was most effective in replenishing both the surface (0–20 cm) and middle (20–40 cm) layers. Rainwater-harvesting ditch irrigation significantly improved the soil water content in both the surface (0–20 cm) and middle (20–40 cm) layers, with minimal changes observed in the deep layer (40–120 cm). Furthermore, soil water variations were significantly influenced by the water uptake of tree roots. In 2022, soil moisture initially increased with distance, then decreased, and subsequently increased again, while in 2023, it increased initially and then stabilized. When the irrigation amount was limited to 75% of the field capacity in the 0–60 cm soil layer, water productivity (WP) reached its optimum, with values of 4.79 kg/m³ (2022) and 5.56 kg/m³ (2023). Based on the simulation results, it is recommended that young apple trees be irrigated using subsurface drip irrigation with a soil layer depth of 30 cm, while soybeans should be irrigated with mulched drip irrigation. Both crops should be irrigated at the podding and filling stages of soybeans, and the irrigation amount should be limited to 75% of the field water capacity in the 0–60 cm soil layer. This study was designed to aid orchard growers in precision irrigation and water optimization. Full article

Water scarcity in Chile, particularly in the Mediterranean region, has been exacerbated by prolonged drought and climate change. Rainwater harvesting systems (RHS) have emerged as viable solutions for addressing water shortages, particularly for agricultural irrigation and aquifer recharge. This study evaluated the implementation and efficiency of RHS in rural areas of the Biobío Region, Chile, through the design and construction of two pilot systems in Arauco and Florida. These systems were assessed based on their water collection capacity, storage efficiency, and monitoring of water level variations in wells after rainwater incorporation, using depth probes to quantify stored volumes. The hydrological design incorporated site-specific precipitation analyses, runoff coefficients, and catchment area dimensions, estimating annual precipitation of 861 mm/year for Arauco and 611 mm/year for Florida. The RHS Arauco collected and stored 40 m³ of rainwater in a flexible tank, while RHS Florida stored 10 m³ in a polyethylene tank, demonstrating the effectiveness of the system. Additionally, we analyzed the economic feasibility and quality of harvested rainwater, ensuring its suitability for agricultural use according to Chilean regulations. The cost-effectiveness analysis indicated that the cost of stored water was $263.51 USD/m³ for Arauco and $841.07 USD/m³ for Florida, highlighting larger systems are more cost-effective owing to economies of scale. The Net Present Value (NPV) was calculated using a discount rate of 6% and a useful life of 10 years, yielding CLP $9,564,745 ($10,812.7 USD) for the Florida and CLP $2,216,616 ($2505.8 USD) for the Arauco site. The results indicate that both projects are financially viable and highly profitable, offering rapid payback periods and sustainable long-term benefits. RHS significantly contributes to water availability during the dry season, reducing dependence on conventional water sources and enhancing agricultural sustainability. Based on the evaluation of the cost–benefit, water availability, and infrastructure adaptability, we infer the feasibility of large-scale implementation at locations with similar characteristics. These findings support the role of RHS in sustainable water resource management and strengthening rural resilience to climate variability, highlighting their potential as an adaptation strategy to climate change in water-scarce Mediterranean regions. Full article

Evapotranspiration plays a vital role in the design of irrigation systems, water resource management, and hydrological modeling, especially in arid and semi-arid regions. This study focuses on projecting evaporation rates using three machine learning models: a Support Vector Machine (SVM), Multi-Layer Perceptron (MLP), and Gaussian Process Regression (GPR), in combination with Principal Component Analysis (PCA) for dimensionality reduction. Meteorological data from 1980 to 2022, including the minimum and maximum temperatures, rainfall, and solar radiation, were used to train and test the models. Projections were made for Kirkuk Governorate by downscaling five global climate models under two climate scenarios: SSP2-4.5 and SSP5-8.5. These scenarios were used to predict future evaporation rates at a rainwater harvesting site for four future periods (P1, P2, P3, and P4) and compare them to the historical reference period (RP). The performance of the models was evaluated using three statistical metrics: Mean Absolute Error (MAE), Root Mean Squared Error (RMSE), and the regression coefficient (R²). Among the models, the MLP demonstrated superior predictive accuracy, with values of MAE = 0.02 mm, RMSE = 0.10 mm, and R² = 0.95. The SVM model showed a slightly lower performance, with MAE = 0.21 mm, RMSE = 0.13 mm, and R² = 0.92. The GPR model’s performance was comparable, yielding MAE = 0.22 mm, RMSE = 0.37 mm, and R² = 0.91. The historical reference period (RP) showed an average evaporation rate of 1370.9 mm per year. Under the SSP2-4.5 scenario, evaporation is projected to increase by 57.2%, while under SSP5-8.5, the increase is projected to be 85.9%. Under the SSP2-4.5 scenario, the evaporation rate for period P1 (2031–2050) showed a slight increase of 1.61%, while for periods P2 (2051–2070) and P3 (2071–2090), the increases were smaller, at 1.89% and 1.93%, respectively. The highest increase occurred in P4 (2091–2100), with a rate of 2.68%, compared to an observed value increase of 1.33%. These findings suggest that climate change will significantly elevate evaporation rates in the region, emphasizing the need for adaptive water resource management strategies. Full article

As water scarcity and environmental sustainability become increasingly critical global concerns, there is a growing need to identify alternative water resources. This study investigates public acceptance of Rainwater Harvesting (RWH) systems in Brunei Darussalam for non-potable uses and ablution purposes. Using an extended Technology Acceptance Model (TAM) framework, the research evaluates key factors influencing public perceptions, including Perceived Ease of Use (PEU), Perceived Usefulness (PU), Attitude Towards Use (ATU), Intentions to Use (ITU), and external factors such as Perceived Cost (PC), Subjective Knowledge (SK), and Technical Requirements (TR). Survey data were analyzed through regression techniques to assess these relationships. The results validate the TAM framework for understanding acceptance of RWH systems and highlight strong positive relationships between PEU, PU, and ATU, with ATU emerging as the strongest predictor of behavioral intentions (ITU). External factors like PC and TR were identified as barriers to adoption, emphasizing the need for financial incentives and technical support. Additionally, subjective knowledge was found to positively influence PU and ITU, underscoring the importance of public awareness campaigns. While concerns about the safety and quality of recycled rainwater were present, they were not significant deterrents to acceptance. The findings also reveal broad support for initiatives such as education, technical guidance, and maintenance services to enhance adoption. Muslim respondents expressed positive attitudes toward using rainwater for ablution, aligning with religious principles of water conservation. This study provides valuable insights for policymakers and relevant agencies to promote RWH systems as a sustainable water management solution, aligning with global Sustainable Development Goals (SDGs) 6 (Clean Water and Sanitation), 12 (Responsible Consumption and Production), and 13 (Climate Action). Full article

Stormwater drainage from urbanised areas has gained importance due to progressing land surface sealing and climate change. More frequent extreme rainfall events lead to overloaded drainage systems and flash floods, particularly in industrial zones experiencing rapid development. The study analysed the sewage system operation in the Special Economic Zone (SEZ) in Lower Silesia, Poland to assess the impact of climate-induced rainfall changes. Three rainfall scenarios were used: model rainfall using historic rainfall intensities, model rainfall using actual intensities, and real precipitation recorded in June 2022. Findings indicate that climate change has negatively affected the stormwater drainage system, resulting in increased overloads and flooding. Particularly, the II scenario showed a significant rise in rainwater inflow to retention reservoirs by 53.1% for ZR-1 and 44.5% for ZR-2 (compared to the I scenario). To address these issues, adaptations are needed for increased rainwater flows, including additional retention facilities, blue–green infrastructure, or rainwater harvesting for the SEZ needs. Full article

At the beginning of human history, surface water, especially from rivers and springs, was the most frequent water supply source. Groundwater was used in arid and semi-arid regions, e.g., eastern Crete (Greece). As the population increased, periodic water shortages occurred, which led to the development of sophisticated hydraulic structures for water transfer and for the collection and storage of rainwater, as seen, for example, in Early Minoan times (ca 3200–2100 BC). Water supply and urban planning had always been essentially related: the urban water supply systems that existed in Greece since the Bronze Age (ca 3200–1100 BC) were notably advanced, well organized, and operable. Water supply systems evolved considerably during the Classical and Hellenistic periods (ca 480–31 BC) and during the Roman period (ca 31 BC–480 AD). Also, early Indian society was an amazing vanguard of technology, planning, and vision, which significantly impacted India’s architectural and cultural heritage, thus laying the foundation for sustainable urban living and water resource management. In ancient Egypt, the main source of freshwater was the Nile River; Nile water was conveyed by open and closed canals to supply water to cities, temples, and fields. Underground stone-built aqueducts supplied Nile water to so-called Nile chambers in temples. The evolution of water supply and urban planning approaches from ancient simple systems to complex modern networks demonstrates the ingenuity and resilience of human communities. Many lessons can be learned from studying traditional water supply systems, which could be re-considered for today’s urban sustainable development. By digging into history, measures for overcoming modern problems can be found. Rainwater harvesting, establishing settlements in proximity of water sources to facilitate access to water, planning, and adequate drainage facilities were the characteristics of ancient civilizations since the ancient Egyptian, Minoan, Mohenjo-Daro, Mesopotamian, and Roman eras, which can still be adopted for sustainability. This paper presents significant lessons on water supply around the world from ancient times to the present. This diachronic survey attempts to provide hydro-technology governance for the present and future. Full article