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A water balance modeling method was developed and applied to assess the water flow impact on urban water systems and water consumption in buildings. The method is based on the computational tool Aquacycle and a case study applied in a city in Brazil. Some modifications have been made to Aquacycle, including using urban drainage and sewage structures commonly applied in Brazil and parameters closer to the Brazilian reality. Such structures are decentralized wastewater treatment systems, deep tubular wells, irregular urban networks, and covered tanks for storing rainwater. Also, an automatic rainwater harvesting system was considered for flood mitigation. The water balance proposed may also be used for a modular assessment approach in urban water systems, aiming to facilitate the application of life-cycle assessment. A case study also aimed to assess alternative water supply in buildings, including scenarios with and without rainwater harvesting. The most significant positive impacts of using rainwater in buildings were a decrease of almost 6% in stormwater runoff and a decrease of water consumption by around 30%. There is a substantial waste of water in the distribution process, which, although it favors groundwater recharge, can have a high impact when considering energy and chemical products consumption. All contributions obtained via modeling can be used to provide specific fluxes in each component that can be used for technical, financial, or environmental evaluations, such as life-cycle approaches, carbon footprint, and cost–benefit assessment. [ABSTRACT FROM AUTHOR]

This research utilized the bagging machine learning algorithm along with the Thornthwaite moisture index (TMI) to enhance the understanding of climate variability and change, with the objective of identifying the most efficient climate service pathways in Sub-Saharan Africa (SSA). Monthly datasets at a 0.5° resolution (1960–2020) were collected and analyzed using R 4.2.2 software and spreadsheets. The results indicate significant changes in climatic conditions in Sudan, with aridity escalation at a rate of 0.37% per year. The bagging algorithm illustrated that actual water use was mainly influenced by rainfall and runoff management, showing an inverse relationship with increasing air temperatures. Consequently, sustainable strategies focusing on runoff and temperature control, such as rainwater harvesting, agroforestry and plant breeding were identified as the most effective climate services to mitigate and adapt to climate variability in SSA. The findings suggest that runoff management (e.g., rainwater harvesting) could potentially offset up to 22% of the adverse impacts of climate variability, while temperature control strategies (e.g., agroforestry) could account for the remaining 78%. Without these interventions, climate variability will continue to pose serious challenges to food security, livelihood generations, and regional stability. The research calls for further in-depth studies on the attributions of climate variability using finer datasets. [ABSTRACT FROM AUTHOR]

The productivity of olive in the northwestern coastal zone of Egypt is significantly constrained by drought and low organic matter in the soil. This study addresses these challenges by exploring the synergistic effects of olive mill wastes (OMW) application and micro-catchment water harvesting techniques on soil properties, runoff, moisture storage, and rainwater harvesting efficiency. Field experiments were conducted over two winter seasons, employing different micro-catchment structures (semi-circular and triangular bunds) and OMW applications. The results revealed that the integration of semi-circular bunds with OMW application (T4) substantially increased rainwater harvesting efficiency by 67.7% and 46.4% in the first and second seasons, respectively. Additionally, T4 and T5 exhibited reduced runoff by 47.8% and 41.3% in the first season and 49.4% and 38.9% in the second season, respectively. T4 significantly enhanced soil organic matter, soil macronutrients (N, P, and K), and micronutrients (Fe, Mn, Zn, and Cu) compared to the control (T1). The study highlights the effectiveness of T4 in improving soil moisture, reducing soil erosion, and enhancing soil fertility. This integrated approach involving OMW application within a semi-circular bund as a water harvesting system proves to be a promising strategy for sustainable olive cultivation in arid conditions. [ABSTRACT FROM AUTHOR]

EPA's stormwater management model (SWMM) has been widely used in the planning and design of stormwater management facilities. SWMM is capable of simulating the hydrologic performance of low-impact development (LID) practices. However, on account of the default parameter setting of the constant water use rate throughout the entire simulation period in the SWMM's LID module for rain barrels (denoted as SWMM-LID), there is a limitation of using it for some design cases where water use occurs only during dry periods. This study aims to investigate the accuracy of the SWMM-LID for modeling the rainwater harvesting system when water is consumed only in dry periods. Rain barrels were also modeled with two alternative methods and their long-term average runoff capture efficiency was evaluated based on simulated data. The first alternative method (SWMM-SC) represents a rain barrel as an equivalent subcatchment in SWMM, while the second (Self-Coded Simulation) uses a self-coded continuous simulation algorithm based on water balance equations. Comparing the Self-Coded Simulation results with the results obtained from SWMM-SC and SWMM-LID for a number of design cases at Atlanta and Billings, US, the SWMM-SC is shown to provide more accurate results than the SWMM-LID. It is therefore concluded that SWMM's LID module for rain barrels may need to be improved to properly model cases where water use occurs only during dry periods, or the proposed way of representing rain barrels as subcatchments may be used for assessing the stormwater volume control performance of rain barrels. [ABSTRACT FROM AUTHOR]

Rainwater harvesting has regained importance in light of increasing water scarcity, particularly in arid and semi-arid regions such as Jordan, as it can be utilized for a variety of uses, including drinking and irrigation. However, the quality of harvested rainwater is of vital importance in determining its intended use, as it may be vulnerable to contamination from different sources during its journey from the atmosphere to storage facilities. Several studies have investigated the water quality issues of the rainwater harvesting system in Jordan, including the quality of direct rain, runoff water, and stored water in cisterns. The factors affecting water quality were also investigated. This paper reviews the rainwater quality harvesting systems in Jordan. The findings revealed that microbial contaminants were frequently reported, exceeding the allowable limits set by the Jordanian standard for drinking purposes. In contrast, direct rain was found to be of better quality. Despite the importance of organic and emerging contaminants in recent water research, minimal attention has been paid to these contaminants. Future research should also focus on options for improving water quality, such as prior treatment measures. [ABSTRACT FROM AUTHOR]

Water harvesting potential was simulated for Budelkani watershed of Sundargarh district, Odisha, India, predicted using water balance model. Model was simulated for 23 years (1983-2015) for short duration variety of rice (108 days). Simulation was done in two variations, firstly in seasonal basis, secondly stage wise. At 50% PE, for 50 mm PWL, SR, rainfall, SI and WHP were best fitted at 120.13 mm, 1144.1 mm, 91.96 mm and 1.52 respectively. They were best fitted by Log-pearson, pareto, EV Type III and pareto respectively. Similarly stage wise, SR also more in stage 1 than stage 2 at quantity of 66.54 and 7.55 mm, respectively and there WHP were calculated to be 1.31. At 50% PE, seasonal values of SR, WHP and SI recorded at 66.23 mm, 1.1 and 79.03 mm, for 100 mm PWL, respectively. They were best fitted by Gamma, Log-pearson and Log normal, respectively. While stage wise, SR at 50% PE were found to be 32.57 to 16.99 mm for stage 1 and stage 2 and WHP at 50% PE, found to be 1.01 in 100 mm PWL. Log-pearson, EV Type III and Log-normal (3-P) PDF were best fitted to SR, WHP and SI at seasonally for 150 mm PWL. At 50% PE, SR, WHP and SI value lies at 65.94 mm, 1.02, 67.72 mm. For 150 mm PWL, best fitted values of SR at 50% PE, for stage 1 and stage 2 were observed to be 15.3 mm, 12.32 mm and likewise, WHP found to be 1. [ABSTRACT FROM AUTHOR]

In recent years, Iran has been dealing with a significant problem. A consistent lack of rainfall, often distributed unevenly across different areas and times. Such weather issues have led to a growing demand for groundwater, resulting in serious social, economic, and engineering challenges in various regions. This study focuses on a thorough examination of the practicality of constructing a reservoir in Kariyan village, located in the Hormozgan province, capable of storing nearly one million cubic meters of runoff water. Various engineering analysis techniques were employed to understand critical parameters that determine the effectiveness of such infrastructure. These parameters include rainfall pattern, rate of evaporation, water pricing, the permeability of the reservoir, local geography, and proximity to the area where the water is needed. This research not only sheds light on the specific case of Kariyan village, but also provides a useful framework that can be applied to similar situations elsewhere. By adopting this comprehensive approach as a practical model, regions grappling with similar water resource challenges can improve their water management, reduce potential negative impacts, and move towards sustainable solutions. This study offers practical insights and strategies to improve water management in arid regions, facilitating sustainable solutions to address water scarcity challenges and minimize negative impacts on communities and ecosystems, also offering practical insights and strategies to ensure the preservation of this essential resource for future generations. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the financial feasibility of rainwater harvesting and greywater reuse in a multifamily building located in Florianópolis, Brazil. A building, consisting of two blocks with 60 flats each, was chosen to obtain data about the number of residents, building characteristics, potable water consumption, and rainwater and greywater demands (obtained by means of questionnaires and water measurements). The financial feasibility analyses considered rainwater and greywater systems separately and together. The impact on the urban stormwater drainage system was evaluated through the reduction of stormwater runoff. The energy consumption in the operational phase of each system was estimated through the amount of energy consumed by the motor pumps to supply one cubic meter of water. The potential for potable water savings through the use of rainwater—that supplies water for washing machines—was approximately 6.9%. The potential for potable water savings through the use of greywater—that supplies water to toilets—was approximately 5.7%. Both systems were feasible. The payback period for rainwater harvesting systems ranged from 57 to 76 months. For greywater systems, the payback period ranged from 127 to 159 months. When considering both systems working together, the payback period ranged from 89 to 132 months. The rainwater harvesting system can reduce 11.8% the stormwater volume destined to the urban stormwater drainage system in relation to the current contribution volume. Energy consumption was approximately 0.56 kWh/m3 of treated water for the rainwater harvesting system and 0.89 kWh/m3 of treated water for the greywater system. Rainwater and greywater were considered economically feasible, especially for higher inflation scenarios. Furthermore, such systems are interesting alternatives in terms of impacts considering urban drainage and energy consumption. [ABSTRACT FROM AUTHOR]

Rainfall runoff may be captured and stored for later use, but the quality of this water can be detrimental in some uses without the use of appropriately designed first-flush diverters. The rainfall runoff water quality was measured on nineteen new small-scale and two aged commercial roofs located near high traffic highways. Roof coverings included asphalt shingles, sheet metal, clay tiles, and tar and gravel. Runoff samples were evaluated for polycyclic aromatic hydrocarbons (PAHs), phosphorus flame retardants (PFRs), and pyrethroid insecticides. Eighteen small-scale roofs were subjected to a range of simulated rainfall events, while natural runoff was sampled on the commercial roofs and one small-scale roof. Runoff was analyzed for pH, conductivity, turbidity, total suspended solids, boron, iron, copper, zinc, manganese, sodium adsorption ratio, nitrate-nitrogen, seventeen PAHs, tris(2-chloroethyl) phosphate, tris(1,3-dichloro-2-propyl)phosphate, bifenthrin, cypermethrin, and lambda-cyhalothrin. Samples from four natural storm events were also analyzed for total coliforms and Escherichia coli. In addition, soils below seventeen existing gutter downspouts were sampled to determine long-term pollutant accumulation. Atmospheric deposition was the main contributor of pollutants in the roof runoff. A majority of samples fell within the U.S. EPA guidelines for non-potable urban and agricultural water reuse. Trace levels of PAHs, PFRs, and insecticides were detected, but all detections were three orders of magnitude below the USGS health-based screening level benchmark concentrations. Results indicate that diverting the first flush, based on turbidity, total suspended solids, or conductivity, can improve the overall water quality and reduce the concentrations of PAHs in harvested rainwater. Downspout soil sampling showed potential for the long-term accumulation of PAHs at concentrations exceeding the minimum human-health risk-based screening levels at these high runoff-loading locations. [ABSTRACT FROM AUTHOR]

A one-year study was conducted to evaluate the impact of air pollution and roof coating on runoff quality. An existing 440 sq meter bitumen roof of a single-story building was coated with an extensive green roof layer on one half. Rainfall and runoff samples from both roofs were collected during 11 rainfall events after the separation of the first flush. The study monitored several key parameters, including pH, electrical conductivity (EC), turbidity, chemical oxygen demand (COD), ammonium nitrogen, nitrate nitrogen, and phosphates. The study revealed that both types of roofs altered the rainfall quality, but the changes caused by the green roof were more substantial. Although the retention of runoff from green roofs has a widely acknowledged positive impact on collecting systems, our study shows that green roofs also result in a 7.5- fold increase in COD concentrations, a 5.4-fold increase in the sum of ammonium and nitrate nitrogen, and a 2.3-fold increase in phosphates compared to bitumen roofs. A clear link between the quality of rainwater/runoff and air pollution was not established. The study's findings will aid in the development and management of local rainwater harvesting systems and enhance global understanding of the primary quality parameters of various roof types, particularly in regions with air pollution. [ABSTRACT FROM AUTHOR]

Rainfall serves as a significant factor contributing to slope stability challenges in mountainous areas, and simulating the process of slope rainwater movement is a crucial approach for analyzing the stability of slopes triggered by rainfall. By combining computer numerical simulation technology with traditional hydraulic and hydrological calculation theories, it is possible to create an efficient and precise rainwater movement model that can simulate and analyze the process of rainwater movement on slopes. Utilizing natural slopes as the focal point of our research, the cellular automaton method was applied to simulate rainfall runoff on slopes, and a Cellular Automata (CA) based model for rainwater movement process was developed. This model modified the Green-Ampt (G-A) infiltration model by adopting an elliptical water content curve and introducing a coefficient that quantifies the ratio of saturated to unsaturated depth. Additionally, we refined the rules governing runoff generation and convergence within the slope and on its surface, enabling a comprehensive simulation of the entire rainwater movement process on the slope. Furthermore, the effectiveness of the model was validated through analytical solutions derived from simplified assumptions, laboratory experiments on infiltration and runoff in the flume, and a case study of a natural slope. The results show that the infiltration calculation results of the rainwater movement model are closer to the experimental values, and their overall values are slightly higher than the measured values, which are basically consistent with the model test results; The runoff calculation results show a phenomenon of initially increasing and gradually approaching the measured values compared to the measured values. When applying the model to an actual slope, it was found that the model comprehensively accounts for the influence of slope seepage, infiltration and runoff process, has better performance compared to G-A modified model. The model can be used to describe the spatial distribution and temporal variation of infiltration and runoff processes. [ABSTRACT FROM AUTHOR]

Straw mulching is a key method for controlling soil and water losses. Mulching costs may be reduced by applying it in strips rather than over entire areas. However, the effect of different straw mulching methods on the effectiveness of reducing soil erosion is unclear. In this study, the effects of straw mulching strip length (covering 1/4, 1/2, 3/4, and 4/4 of the slope length) and coverage rate (0.2, 0.5, and 0.8 kg m−2) on interception, infiltration, runoff, and soil erosion were investigated at the plot scale using rainfall simulation experiments. The further complex correlations between these variables were analyzed using structural equation modeling (SEM). Bare slopes were used as a control group. The rainfall intensity was chosen to be 60 mm h−1. The results showed that (1) the modified Merriam interception model can describe the change in interception with time under straw mulching conditions well (R2 > 0.91, NSE > 0.75). (2) A total of 35.39–78.79% of the rainwater is converted into infiltration on straw-covered slopes, while this proportion is 36.75% on bare slopes. The proportion of rainwater converted to infiltration was greatest (78.79%) when the straw covered 3/4 of the slope length at a coverage rate of 0.5 kg m−2, which was the most conducive to rainwater harvesting on the slope. (3) Straw mulching protects the topsoil from the impact of raindrops and directly affects the sediment yield (direct effect = −0.44). Straw mulching can also indirectly affect sediment yield by increasing interception, reducing runoff, and decreasing the sediment carrying capacity of runoff (indirect effect = −0.83). Compared with bare slopes, straw covering at least 1/2 of the slope length can significantly reduce runoff yield, but straw covering only 1/4 of the slope length can significantly reduce sediment yield. Moreover, once the straw mulch slope length reaches 3/4 and the coverage rate reaches 0.5 kg m−2, further increases in mulch slope length and coverage rate will not significantly reduce the runoff and sediment yields. These results assessed the effectiveness of different straw mulching methods in controlling soil and water losses on sloping farmland. [ABSTRACT FROM AUTHOR]

The impact of global climate change on water resources is a pressing concern, particularly in arid and semi-arid regions, where water shortages are becoming increasingly severe. Rainwater harvesting (RWH) offers a promising solution to address these challenges. However, the process of selecting suitable RWH sites is complex. This paper introduces a comprehensive methodology that leverages various technologies and data sources to identify suitable RWH locations in the northern region of Iraq, considering both historical and future scenarios. The study employs remote sensing and geographic information systems to collect and process geospatial data, which are essential for the site selection process. AHP is utilized as a decision-making tool to assess and rank potential RWH locations based on multiple criteria, helping to prioritize the most suitable sites. The WLC approach is used to combine and weigh various factors, enabling a systematic evaluation of site suitability. To account for the uncertainty associated with future climate conditions, a stochastic weather generator is employed to simulate historical and future precipitation data for period (1980–2022) and (2031–2100). This ensures that the assessment considers changing climate patterns. Historical precipitation values ranged from 270 to 490 mm, while future projections indicate a decrease, with values varying from 255 to 390 mm. This suggests a potential reduction in available water resources due to climate change. The runoff for historical rainfall values ranged from 190 mm (poor) to 490 mm (very good). In the future projections, runoff values vary from 180 mm (very poor) to 390 mm (good). This analysis highlights the potential impact of reduced precipitation on water availability. There is a strong correlation between rainfall and runoff, with values of 95% for historical data and 98.83% for future projections. This indicates that changes in precipitation directly affect water runoff. The study incorporates several criteria in the model, including soil texture, historical and future rainfall data, land use/cover, slope, and drainage density. These criteria were selected based on the nature of the study region and dataset availability. The suitability zones are classified into four categories for both historical potential and future projections of RWH zones: very high suitability, covering approximately 8.2%. High suitability, encompassing around 22.6%. Moderate suitability, constituting about 37.4%. Low suitability, accounting for 31.8% of the study region. For the potential zones of RWH in the future projection, the distribution is as follows: very high suitability, approximately 6.1%. High suitability, around 18.3%. Moderate suitability, roughly 31.2%. Low suitability, making up about 44.4% of the study region. The research's findings have significant implications for sustainable water resource management in the northern region of Iraq. As climate change exacerbates water scarcity, identifying suitable RWH locations becomes crucial for ensuring water availability. This methodology, incorporating advanced technology and data sources, provides a valuable tool for addressing these challenges and enhancing the future of water management to face of climate change. However, more investigations and studies need to be conducted in near future in the study region. [ABSTRACT FROM AUTHOR]

Low-impact development practices (LIDs) have been used to reduce the impacts of flash floods in Brazil. However, there is a lack of investigations on their construction costs concerning the effects on the mitigation of flash floods. This paper addresses the construction costs and the runoff reduction by using seven scenarios of LIDs for a 32-km2 basin in the Midwest Brazil region. The LIDs considered were permeable pavement (PP), rainwater harvesting (RWH), and infiltration trenches (IT). The first three LID scenarios considered PP, RWH, and IT techniques, respectively, and the other four used different combinations of the three LIDs. Scenario 3 showed a decrease of 15% in the runoff, achieved at a lower cost using only IT. This result corresponds to a 2.6% runoff reduction per $1 million spent. These analyses may help in the identification of the balance between benefit and cost by local stakeholders for the use of LIDs. [ABSTRACT FROM AUTHOR]

The study evaluated rainwater quality harvested from roof top catchments viz Asbestos, Aluminum, Corrugated and Harvey roof tops in southeastern, Nigeria. Chemical and microbiological species viz pH, Total Dissolved Solids(TDS), Electrical conductivity (EC), Nitrate(NO3−), Sulphate (SO42−), Chloride(Cl−), Total bacteria load(TBL), Total Coliform Count (TCC), Salmonella Shigella Agar (SSA), Thiocitrate Bile-salt Sucrose(TCBS), Eosin Methylene Blue (EMB) were investigated from samples of rainwater roof top run off during onset rain (April), peak rain (July) and cessation (October) rain events in 2022. Results of chemical parameters show significant variation p ≥ 0.05 among the catchments with increased mean concentration of pH(6.5), TDS(25.7 mg/l), EC(43.6μS/cm),NO3−(0.72 mg/l) SO42(4.73 mg/l), Cl(8.81) during onset rain more than the peak and cessation rain, with asbestos rainwater having the highest levels but below WHO/FMENV drinking water limit. Positive and negative correlations existed between the chemical parameters in temporal scale and originating from human activities with the temporal variability in decrease order: April ≥ October ≥ July. Microbial parameters in rainwater revealed mean TBL(6.6 × 104 cfu/ml), TCC(2.6 × 103 cfu/ml) and control (5.8 × 104 cfu/ml) with Aluminum top (8.2 × 104 cfu/ml) recording highest in onset rain more than the peak and cessation rain events. All of the microbial parameters were above the WHO standards which indicates a very high public health risk if consumed without treatment. Organisms found in rainwater from roof types are: Enterobacter sp., Staphylococcus aurous, Streptococcus sp., Bacillus Sp. and Escherichia coli. Based on the results, treatment of rainwater, operation, maintenance methods should be upheld for quality assurance of harvested rainwater. [ABSTRACT FROM AUTHOR]

Recent climatic changes and anthropogenic activities considerably affect regional water resources, particularly in water‐scarce regions. The present study, therefore, aims to understand the changes in monsoon rainfall, potential evapotranspiration (PET), surface runoff, dam storage and groundwater in the drought‐prone region of Maharashtra. The analyses of trend and step‐change were carried out using standard parametric tests. The results were verified with the application of non‐parametric statistical techniques. Notably, monsoon rainfall and runoff were observed to be declining. Exceptionally, the Yerala Basin witnessed significant increase in rainfall along with heavy rainfall events. Contradictorily, Agrani and Man Basins registered a notable decline in rainfall and runoff. As vulnerability to hydrological disasters is high, these basins should be carefully monitored. Although surface water harvesting brought a positive change in post‐monsoon groundwater level, it was the main reason for a decline in runoff volume at downstream reaches, which led to intra‐basin water disparity. The study area witnessed significant increase in groundwater extraction. Unfortunately, the misuse of government‐subsidized schemes exacerbates groundwater exploitation and stockpiling of water resources. Moreover, the increasing rate of PET augments hydrological losses and amplifies water distress. Interestingly, almost all the hydrological changes were notably experienced during the post‐2000 period. To cope with present and future water scarcity problems, it is therefore necessary to restrict irrational use and allocation of available limited water resources. The findings that emerge from this investigation may help to formulate judicious water policies and plans which could be implemented by the government, agronomists, water resource managers and farmers. [ABSTRACT FROM AUTHOR]

Green Infrastructure (GI) treats stormwater runoff by filtering and absorbing it at its source, utilizing soil and plants, permeable surfaces, rainwater harvesting, and more. Although GI is useful in mitigating stormwater runoff, gaining community acceptance and implementing GI face challenges because the approach is unique and unfamiliar to the public. Various forms of public outreach in the planning and design process can help create more awareness around GI, which can be critical for its successful promotion and application. This study focused on educating the public about GI with two main objectives: 1) Exploring the effectiveness of GI education by comparing survey participants' perceptions of GI before and after GI education session and 2) evaluating the materials used in GI education to develop effective strategies for informing the public. The authors employed the 5E model, a research-based lesson planning tool, to structure the GI education and develop education materials. Survey participants included future secondary school teachers who, because of their potential to connect with numerous students, were selected to expand the reach of GI education. Their role in this study also involved evaluating the educational materials that were developed. The survey results revealed that GI education had a positive impact on increasing the participants' understanding of GI and their intention of promoting it. This study is significant not only for measuring the effectiveness of GI education but also for suggesting implications for the development of educational materials, particularly in the area of landscape architecture. [ABSTRACT FROM AUTHOR]

Runoff response to multiple land‐use changes and climate perturbations is distinct, and the main influencing factors vary significantly in different regions. However, few have simultaneously considered the effects of multiple land use changes (vegetation cover changes, terraces and check‐dams construction, and urban expansion) and climatic perturbations (precipitation, potential evapotranspiration, and temperature) on runoff and constructed separate expressions for distinct study areas. This article attempted to determine the main influencing factors of runoff according to the fitting function in the eight subregions of the middle Yellow River (MYR), construct the expressions between the controlling parameter in the Budyko framework and the main factors, and quantify the contribution of climate factors and land use changes to runoff by combining the elasticity coefficient in each subregion. The results indicated that climate factors and land use changes could significantly impact controlling parameters, and there were differences between regions. Climate change promoted an increase in runoff, while land use change promoted its reduction, and the reduction value outweighed its increase. In terms of land use changes, increasing vegetation coverage could suppress runoff reduction, while constructing terraces and check‐dams could promote its reduction. The urban expansion benefited runoff collection and, therefore, could suppress runoff reduction. Its absolute contribution rate exceeded 200% in apparent urban expansion areas. In addition, the contribution rates of land use to runoff changes in the northern arid and semi‐arid regions were significantly higher than those in the southern, and they were more sensitive to land use changes. The research results can provide a reference for analysing the runoff response to different land‐use changes and can further advance people's understanding of the water cycle. [ABSTRACT FROM AUTHOR]

Most lands in the Brazilian semi-arid region are covered with native vegetation (Caatinga) with limited agricultural practices due to chronic water-scarcity issues. However, clearing the native vegetation and using the land for agriculture is becoming a common practice. The objective of this study was to evaluate the effectiveness of forage palm and stone barrier in reducing runoff and erosion compared to native vegetation. The study was conducted in the Jatobá experimental basin, Brazil, using runoff plots with three surface covers: Caatinga, forage palm barrier, and stone barrier. Data collection includes runoff and erosion rates, and soil moisture dynamics at two depths (0–20 and 20–40 cm) in response to rainfall events. Rainfall characteristics were also recorded and analyzed for 30 min for intensity (I30) and erosivity (EI30). Results showed that stone barrier and forage palm treatments were not as effective as the native vegetation Caatinga in reducing soil loss. Stone barrier was the least effective in reducing runoff and soil loss. However, runoff from forage palm was not statistically different from Caatinga. In addition, forage palm improves soil moisture dynamics at two depths. The study findings highlighted the importance of the Caatinga for soil, water and biome conservation in the region. However, the study also suggested that in the places where agricultural practices are conducted, using forage palm as a soil-conservation strategy could be a good alternative. Additional benefits of forage palm include its suitability for intercropping with other crops, and that it can serve as an alternative for animal feed in the region. Information from this study could be used to inform land management and soil- and water-conservation efforts in the semi-arid region of Brazil. [ABSTRACT FROM AUTHOR]

The spinal structures found on Copiapoa cinerea var. haseltoniana, an efficient dew-harvesting cactus, were fabricated and evaluated both in a climate chamber and outdoors in dewy conditions. A mix of aluminium and steel was used to fabricate these surfaces, with aluminium being used for everything but the replicated spine features, which were constructed from steel. Each surface was entirely coated with a highly emissive paint containing an alumina–silicate OPUR additive. Three replica versions (stem only, spine only, and stem & spine) were compared to a flat planar reference surface. Experimental results demonstrated that all three biomimetic macro-structured surfaces significantly enhanced dew harvesting compared to the reference surface. It was established that the stem & spine replica, spine replica, and stem replica all demonstrated significantly more dew harvesting, with mean efficiency ratios in respect of the reference surface of 1.08 ± 0.03, 1.08 ± 0.02, and 1.02 ± 0.01, respectively. Furthermore, the method of surface water collection was found to influence the water collection rate. The diagonal run-off flow across a flat planar surface was 34% more efficient than the parallel run-off flow on the same surface. These findings provide valuable insights for the construction and installation of biomimetic-inspired dew-harvesting devices, particularly in regions that are most challenged by decreasing dew yields as a result of climate change. [ABSTRACT FROM AUTHOR]

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The use of rainwater is widely recognized as a dependable solution to reduce and mitigate the effects of water scarcity. Research on rainwater harvesting systems has increased significantly in recent years, especially on methods and treatment systems. A rainwater harvesting system can be described as collecting and storing rainwater that can be used rather than waste as runoff. A rainwater collection system might lessen the reliance on the public water supply. This study aims to determine the suitability of a rainwater harvesting system at a double-story house, thus identifying the suitable tank size for installation. This study's analysis used the Tangki NAHRIM 2.0 with localized input data such as rainfall, suitable roof area, and roof runoff coefficient. Findings from this study indicate that installing the rainwater harvesting system at a double-story house is suitable, and the optimum tank size is 3 m³ by considering all the activities that contribute to water usage. Concisely, installing a rainwater harvesting system can reduce the monthly water bill and minimize the usage of treated water, thus preventing water scarcity in the future. [ABSTRACT FROM AUTHOR]

Communities in semi-arid lands use sand dams to enhance access water during the dry seasons. However, there is limited information on the quality of water derived from these sand dams, especially in degraded lands where storm surface runoff poses contamination risk. Thus, this study aimed at assessing the spatial–temporal variations in water quality of sand dams in Chepareria, West Pokot County in Kenya. Water samples were collected from scooping holes across 18 purposefully selected sand dams. Results obtained showed significant differences in water quality based on a sand dam's age and location of the scooping holes, but the magnitude of these differences differed with specific properties. For instance, in recently constructed sand dams (<1 year), scooping holes near the sand dam wall had lower pH values (8.5) than holes scooped a distance from the sand dam wall (9.2). For total dissolved solutes and microbial properties, sand dam age had the greatest impact, over the location of the scooping holes. For example, water obtained from <1 year old sand dams had significantly higher TDS with an average value of 100.3 mg L−1. The thermotolerant coliforms (TTC) exceeded the maximum allowable levels recommended by The World Health Organization. Thus, water obtained from these sand dams should be treated before consumption. Finally, sand dams meant for domestic water harvesting should be protected. Shallow wells with appropriate aprons for effective protection against contamination should be installed to enhance abstraction of safe water from sand dams. [ABSTRACT FROM AUTHOR]

Iraq, including the investigated watershed, has endured destructive floods and drought due to precipitation variability in recent years. Protecting susceptible areas from flooding and ensuring water supply is essential for maintaining basic human needs, agricultural production, and industry development. Therefore, locating and constructing storage structures is a significant initiative to alleviate flooding and conserve excessive surface water for future growth. This study aims to identify suitable locations for Runoff Harvesting (RH) and dam construction in the Hami Qeshan Watershed (HQW), Slemani Governorate, Iraq. We integrated in situ data, remotely sensed images, and Multi-Criteria Decision Analysis (MCDA) approaches for site selection within the Geographical Information Systems (GIS) environment. A total of ten criteria were employed to generate the RH suitability maps, including topographic position index, lithology, slope, precipitation, soil group, stream width, land cover, elevation, distance to faults, and distance to town/city. The weights of the utilized factors were determined via Weighted Linear Combination (WLC) and Analytic Hierarchy Process (AHP). The resulting RH maps were validated through 16 dam sites preselected by the Ministry of Agriculture and Water Resources (MAWR). Findings showed that the WLC method slightly outperformed AHP regarding efficiency and exhibited a higher overall accuracy. WLC achieved a higher average overall accuracy of 69%; consequently, it was chosen to locate new multipurpose dams for runoff harvesting in the study area. The overall accuracy of the 10 suggested locations in HQW ranged between 66% and 87%. Two of these sites align with the 16 locations MAWR has recommended: sites 2 and 5 in the northwest of HQW. It is noteworthy that all MAWR dam sites were situated in medium to excellent RH zones; however, they mostly sat on ineffective geological localities. It is concluded that a careful selection of the predictive factors and their respective weights is far more critical than the applied methods. This research offers decision-makers a practical and cost-effective tool for screening site suitability in data-scarce rugged terrains. [ABSTRACT FROM AUTHOR]

The relevance of the article is due to the importance of the problem of water drainage at modern construction sites. When designing buildings and structures, it is necessary to take into account the possibility of efficient collection and drainage of water from the surface of the roof and the territory. The goal is to represent relevant information about the methods of hydraulic calculation of rainwater elements used in modern engineering practice. Among the methods used in the research, the analytical method, synthesis method, functional method, deduction method, and other approaches were used. The scientific and practical task related to the development of new and improvement of known methods of modelling rain run-off in built-up areas, taking into account the regulatory influence of individual elements of water drainage structures, is being successfully carried out. The results of this study are very important for ensuring the reliability of water drainage systems in the settlements of Ukraine, especially under the conditions of the growth of urban development and changes in climatic conditions. To develop practical surface run-off management plans, it is necessary to scientifically model the run-off level, taking into account the climatic characteristics and parameters of the run-off basin, as well as the predicted changes over time. The task of modelling the behaviour of surface run-off in urbanized areas is complex and it contains many factors. The study shows that reliable modelling results of complex rainwater drainage systems with regulating facilities can be obtained only with the help of multifactorial and multistep models implemented with the help of computer programs. The practical value of the research is that it helps to improve the design and operation of water drainage and water supply systems. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Kirkuk University for Agricultural Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Iraqi Journal of Desert Studies is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The consequences of climate change are exacerbated by landuse changes, which influence rainfall-runoff relations and, consequently, flood risk. Effectively, urbanisation is steadily contributing to increasing impervious areas and reducing the time-to-peak. The effect of nature based solutions (NBSs) on mitigating these phenomena is recognised. Nevertheless, these kinds of sustainable infrastructures are still barely known and scarcely adopted in many parts of European Countries. The LIFE BEWARE project aims to enhance hydraulic safety and spread good practices in rainwater management by promoting and facilitating the adoption of NBSs in the Altovicentino area (Northern Vicenza Province, Veneto Region, Italy). To support the dissemination activities, some full-scale NBSs have been created within the municipality areas involved in the project. The hydrological impact of the structures is continuously monitored thanks to the installation of devices measuring inlet and outlet runoff and rainfall patterns. This study aims to analyse the monitoring data of the first two years of the built NBSs. Results show that the structures managed almost all the water runoff through processes of infiltration and retention, providing additional insights into understanding the real behaviour of NBSs exposed to the specific environmental conditions of a very rainy foothills area. In particular, mean rain intensity and rainfall duration are the variables that mostly affected the structure performance, especially for events prolonged over time (2-3 days) with mean rainfall intensity in the range of 2-3 mm/h. Therefore, the overall outcomes from this analysis were useful for improving the design of NBSs and further promoting their installation in urban areas. [ABSTRACT FROM AUTHOR]

Livestock production in drylands requires consideration of the ecological applications of ecohydrological redistribution of water. Intensive cattle trampling and the associated increase of surface runoff are common concerns for rangeland productivity and sustainability. Here, we highlight a regional livestock production system in which cattle trails and trampling surrounding an artificial impoundment are purposely managed to enhance redistribution and availability of water for cattle drinking. Based on literature synthesis and field measurements, we first describe cattle production systems and surface water redistribution in the Dry Chaco rangelands of South America, and then develop a conceptual framework to synthesize the ecohydrological impacts of livestock production on these ecosystems. Critical to this framework is the pioshere—a degraded overgrazed and overtrampled area where vegetation has difficulties growing, usually close to the water points. The Dry Chaco rangelands have three key distinctive characteristics associated with the flat sedimentary environment lacking fresh groundwater and the very extensive ranching conditions: (1) cattle drinking water is provided by artificial impoundments filled by runoff, (2) heavy trampling around the impoundment and its adjacent areas generates a piosphere that favors runoff toward the impoundment, and (3) the impoundment, piosphere, and extensive forage areas are hydrologically connected with a network of cattle trails. We propose an ecohydrological framework where cattle transit and trampling alter the natural water circulation of these ecosystems, affecting small fractions of the landscape through increased runoff (compaction in piosphere and trails), surface connectivity (convergence of trails to piosphere to impoundment), and ponding (compaction of the impoundment floor) that operate together making water harvesting and storage possible. These effects have likely generated a positive water feedback on the expansion of livestock in the region with a relatively low impact on forage production. We highlight the role of livestock transit as a geomorphological agent capable of reshaping the hydrology of flat sedimentary rangelands in ways that can be managed positively for sustainable ranching systems. We suggest that the Dry Chaco offers an alternative paradigm for rangelands in which cattle trampling may contribute to sustainable seminatural production systems with implications for other dry and flat rangelands of the world. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering (17264073) is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The runoff-sediment relationship is one of the most important aspects to reflect the variation of runoff and sediment. There is a significant impact of the rainstorm on the runoff collection and sediment transport in the watershed. It is a high demand to explore the runoff-sediment relationship under the condition of a single rainstorm in the control of soil and water loss. Heretofore, most research was focused mainly on the northern region of China. It is still lacking in the southern region with frequent rainstorm and flood. Taking the Lianshui watershed located in southern Jiangxi Province as the research area, this study aims to launch the project of forest rehabilitation from slope agriculture, large-scale orchard development, and urbanization construction over the past 30 years. The underlying surface was changed significantly. The characteristics of runoff and sediment were analyzed to determine the relationship between them under different flood types and periods using a cluster, discriminant, and Spearman correlation analysis, according to the hydro-meteorological and land use data from 1965 to 2020 under the condition of a single rainstorm. The hysteretic relationship was then established between the runoff and sediment. The results showed that: 1) The 120 rainstorm floods in the watershed were divided into three types, with the occurrence frequency from the high to the low as Type III, Type I, and Type II, where the proportion were 63.3%, 32.5%, and 4.2%, respectively. The smallest eigenvalue was found in the runoff and sediment transport of Type III flood. The longest flood duration was in the Type I flood. The other eigenvalues were in the middle level. The Type II flood presented the largest eigenvalue, except for the middle-level flood duration. There was a highly correlated runoff depth and sediment transport in the three flood types. The Spearman correlation coefficients were 0.515, 0.800, and 0.481, respectively. 2) Five periods (1965-1975, 1976-1985, 1986-1995, 1996-2005, and 2006-2020) were divided by the whole study period. There was the highest average value of runoff depth and flood duration in 1986-1995, whereas, the average value of peak flow reached the highest in 1976-1985. The eigenvalue of sediment transport in 1996-2005 and 2006-2020 increased significantly, compared with the previous three periods, while the sediment transport capacity of unit runoff raised significantly. 3) The proportion of runoff-sediment loop curves in the type of the clockwise, counterclockwise, positive figure-eight, reverse figure-eight, and compound type were 18.3%, 17.5%, 26.7%, 15.8%, and 21.7%, respectively, among the 120 rainstorm floods. Meanwhile, there was a great variation in the proportion of runoff-sediment loop curves under different flood types. The highest proportion in Type I, Type II and Type III flood were the compound (33.3%), clockwise (40.0%), and positive figure-eight type (30.3%), respectively. However, the highest proportion of counterclockwise and figure-eight type curves was found in the period of 1996-2005 and 2006-2020, respectively, which was closely related to the changes in the location and quantity of sediment sources caused by the large-scale development of orchards in the watershed. The proportion of compound type curve reached the maximum in 1986-1995, due mainly to the high average value of runoff depth and flood duration. The finding can provide the scientific basis for the management and regulation of runoff and sediment in the watershed, in order to implement soil and water conservation measures [ABSTRACT FROM AUTHOR]

Increased urbanization combined with the intensification of short rainfall events has worsened the urban flood issue. Among the different blue-green solutions to mitigate pluvial floods, green roofs (GR) and rainwater harvesting (RWH) have been investigated as sustainable systems to reduce runoff from rooftops. Their flood mitigation capacity, however, has been estimated mostly at building-scale. Following the need to estimate discharge reduction at large scale over entire cities, we simulated the installation of (extensive, intensive and multilayer blue) GRs on flat roofs and RWH systems for sloped ones. Performances of such systems were investigated in selected cities, representing different climate regimes. Although at building-scale GRs showed higher retention capacity, the cost-efficiency analysis highlights that at large-scale RWH tanks ensure higher retention with lower costs, due to rooftop distribution. The coupled system of multilayer blue-GRs and RWH tanks guarantees a discharge reduction of 5% even during extreme events. [ABSTRACT FROM AUTHOR]

Rainwater harvesting (RWH) has proven to be an efficient method of curtailing water scarcity by substituting it as an alternative water supply which also helps to mitigate the risk of flooding caused due to heavy rainfall. While overcoming the water-related issues, implementation and identifying potential harvesting sites in urban areas on a large scale has always been challenging, necessitating additional research and constraint considerations. The proposed study implements a basin-wide approach and creates a tool using the geographical information system (GIS) to pinpoint site locations to collect rainstorm water. For determining the feasible number of RWH sites, the scenarios were created by considering the minimum basin area. In addition, the volumetric potential of the identified RWH sites was evaluated using the SCS-CN (Soil Conservation Services Curve Number) method by estimating rainfall runoff volume. The proposed methodology is implemented as a case study on the extended area of Jaipur in India, and the analysis shows that all identified locations lie on the outskirts of the study area, ensuring land availability for developing rainwater harvesting structures. As an outcome, the proposed methodology helps to establish the relationship between the basin area, the number of identified RWH sites, and their volumetric potential, creating a benchmark for further conducting similar studies on other areas. [ABSTRACT FROM AUTHOR]

Stormwater runoff control is often a concern due to urbanization and extreme rainfall events. Sustainable urban drainage systems can support traditional hydraulic networks in rainwater management by providing local runoff disposal and reuse of collected stormwater. The objective of the study is based on an innovative analytical-probabilistic approach for evaluating the functioning of rainwater tanks in stormwater management with the potential for using collected water for non-potable purposes. A pilot case of a rainwater tank integrated with an infiltration system was considered within the framework of the Polisocial Award 2023 at the Off-Campus Cascina Nosedo of Politecnico di Milano (Italy). The performances of the rainwater tank in satisfying irrigation were evaluated through a new version of an analytical probabilistic approach, whose validation confirmed it is promising and offers excellent perspectives in the field of stormwater management. The probabilistic equation developed in this study relates the probability of rainwater reuse to the main parameters involved in the process (i.e., storage volume, irrigation area, rainfall depth, etc.), enabling to define the management rules of the storage for the optimization of the stormwater management. In the application, to consider an irrigation area lower than 30 m2, ensures the fully meeting of the requirements by the system in the rainiest year, and to avoid falling below the 50% (2-year return period) during the driest year. [Display omitted] • A new version of an analytic-probabilistic model for optimal rainwater management. • Aggregation of previous chained rainfall events into a single parameter. • Integration of different SUDS to meet multiple targets. • The validation in a pilot system in Milan (Italy) confirmed the model's reliability. [ABSTRACT FROM AUTHOR]

According to the current codes and specifications, the calculated value of the storm runoff for storage yards in coal and ore terminals is directly related to the minimum value of annual maximum daily rainfall depth. But, this value is small, which is likely to cause dusty rainwater to overflow into the sea. In this paper, through statistical analysis of the rainfall data of 15 typical port areas, the reasonable rainfall value for the calculation of the storm runoff of storage yard is discussed. The results show that the average value of annual maximum daily rainfall depth can better reflect the local annual comprehensive rainfall characteristics. It will not cause a significant increase in the scale of rainwater storage facilities, but can greatly reduce the probability of rainwater overflow in storage yard. Therefore, it is recommended to take the average value of annual maximum daily rainfall depth as the rainfall value for the calculation of the storm runoff for storage yards. [ABSTRACT FROM AUTHOR]

The water issue has become a frontier of public debate globally due to public awareness of sustainable development. Nigeria's water resources are under serious threat from inadequate catchment management that includes widespread pollution from indiscriminate waste disposal. Stormwater is now recognized as a valuable resource rather than a nuisance, especially in large urban centers. Growing demand for water has exerted pressure on groundwater via dug well and boreholes scattered virtually in every dwelling in Nigeria. This challenge motivated this investigation of the feasibility of harvesting stormwater for due purposes of supplementing water supply and flash flood management. This study aims at quantification of harvestable stormwater and identification of potential capturing sites using Spatial Hydrological Analysis of GIS model and Synthetic Hydrograph. The result indicated total harvestable stormwater for 24-hr rainfall of 161.3 Mm3 and three available capturing sites of eight depressions identified. This volume is a good incentive to incorporate storm harvesting in overall water resources sustainable management. [ABSTRACT FROM AUTHOR]

Purpose: Environmentally friendly mulching material and appropriate tillage practice are needed to solve plastic film residues in agricultural production in ridge-furrow rainwater harvesting technology (RFRHT) in the Loess Plateau in China. Materials and methods: A field experiment in randomized block design was conducted to (1) investigate the runoff coefficient for three ridge widths (30, 45, and 60 cm) using three ridge mulching materials (ridges compacted with soil (RCS), maize straw biochar-soil mixture (SBM), and cow dung biochar-soil mixture (DBM)); (2) the effects of three ridge widths using three ridge mulching materials on soil moisture, temperature, nutrients, fodder yield, quality, and water use efficiency (WUE) of sainfoin and conventional flat planting (FP) as a control, during two consecutive sainfoin-growing years: 2017 and 2018. Results: The predicted runoff coefficient for RCS30, RCS45, RCS60, SBM30, SBM45, SBM60, DBM30, DBM45, and DBM60 (subscripts 30, 45, and 60 referred to ridge widths) was 0.31, 0.33, 0.34, 0.26, 0.30, 0.31, 0.22, 0.24, and 0.25, respectively, over 2 years. DBM had a higher concentration of total nitrogen and organic matter compared to SBM, while SBM had a higher concentration of Olsen phosphorus and available potassium compared to DBM. The higher runoff coefficient and soil moisture in SBM led to higher fodder yield, WUE, and condensed tannin content of sainfoin, compared to DBM. Compared to FP, in RCS, fodder yield and WUE of sainfoin decreased by 8.8–17.8% and 0.6–2.6 kg ha−1 mm−1, respectively. Condensed tannins concentration of sainfoin for RCS, SBM, and DBM increased by 4.1 −9.0%, 11.4 −21.8%, and 9.4 −15.2%, respectively. Fodder yield in SBM and DBM increased by 14.3 −19.5% and 7.1 −10.0%, respectively, while WUE in SBM and DBM increased by 6.7 −8.5 and 4.7 −5.5 kg ha−1 mm−1. Conclusion: Ridges compacted with biochar-soil mixture, especially with maize straw biochar-soil mixture, increased fodder yield, WUE, and condensed tannin content of sainfoin. The optimum ridge width in SBM and DBM for sainfoin production was 46–49 and 41 cm, respectively. [ABSTRACT FROM AUTHOR]

Copyright of LHB: Hydroscience Journal is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atlantic Review of Economics / Revista Atlántica de Economía is the property of Colegio de Economistas de La Coruna and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Rainwater harvesting (RWH) is the first-rated and cost-effective measure in resolving water crises issue. The monthly mean rainfall data for 31 years (1986 to 2016) was studied to calculate the RWH potential. The study area (Gulberg Greens, Islamabad) was divided according to its intended use for residential farmhouses, public facilities, commercial buildings, public parks, roads, and graveyards covering 573, 207, 47, 190, 212, and 14 hectares (ha) respectively. The RWH potential of each area was estimated using the runoff curve number (RCN) method considering the landscape slope, soil type, land use, and antecedent moisture content. Three alternative landscaping patterns were studied for each farmhouse, having different areal coverage for fruits, vegetables, and land cover. The Blaney-Criddle equation was applied to estimate the crop water requirements of each landscaping alternative. The monthly harvested rainwater volume from each farmhouse was compared to its monthly irrigation demand for each landscaping alternative. The results indicated similar patterns of RWH potential for farmhouses of 0.506, 0.252, and 0.202 ha, with minimum volume in December (0.07, 0.03, and 0.02 million liters (ML), respectively) and maximum volume in July (1.21, 0.66 and 0.51 ML, respectively). The total RWH volume from farmhouses, roads, streets, public parks, public facilities, commercial buildings, and the graveyard was 4608, 2087, 1205, 1665, 530, and 112 MLy−1 respectively. Similarly, the monthly irrigation water demand for the seven months (Jan, Feb, Mar, Jul, Aug, Sep, and Dec) was completely satisfied by the harvested rainwater and for the remaining months (Apr, May, Jun, Oct, and Nov), the demand was fulfilled from 30 to 80%. Furthermore, the annual saving from RWH is around Rs. 500, 245, and 200 thousand for 0.506, 0.252- and 0.202-ha farmhouses, respectively. [ABSTRACT FROM AUTHOR]

• Comparison of TIA, DCIA, and EIA as imperviousness indicators in urban catchments. • Underestimated TIA due to the presence of tree canopy and the necessity of modifying high-resolution LC via unshading. • Similar %TIA from low-resolution NLCD imperviousness and unshaded, high-resolution LC. • The assumption of zero to 40 % rooftop connectivity resulted in comparable DCIA and EIA in the study catchments. • In the absence of catch basin inlet data, roads can be used as runoff collection system for DCIA delineation. Urban watershed hydrologic and water quality models, and stormwater control measure (SCM) designs, rely on accurate determination of stormwater runoff volume and impervious areas contributing to runoff. This research assesses the impacts of data availability and spatial resolution on two of the main indicators of urban impervious cover: total impervious area (TIA) and directly connected impervious area (DCIA). The research also explores the relationship between TIA, DCIA, and the effective impervious area (EIA), another important indicator of urban impervious cover. Using spatial programming, surface runoff was tracked, from originated to discharged locations, in nine urban catchments (ranging from 16 to 2035 ha) in Minnesota, USA, under various scenarios combining geospatial data types and resolutions. TIA fractions derived from low-resolution, nationally available imperviousness data were not statistically different than those from high-resolution land cover (LC) data modified by "unshading" to remove tree canopies overlaying impervious surfaces. Comparison of DCIA and EIA values indicated that modified LC is preferable for accurate DCIA delineation in ungauged catchments. EIA was 65 % of DCIA under the assumption that all rooftops were connected to sewer systems, while it exceeded DCIA by 34 % assuming all rooftops were unconnected, underscoring the importance of rooftop connectivity information in urban areas. The assumption of 0 % to 40 % rooftop connectivity resulted in comparable DCIA and EIA values in the study catchments. Using roads as the runoff collection system (instead of sewer inlets) did not significantly alter DCIA values at 5 % level, when unshaded LC was used. Given the absence of observed runoff data in most urban areas, DCIA serves as an appropriate imperviousness indicator for determining runoff in ungauged urban watersheds. However, achieving accurate DCIA delineation necessitates high-resolution LC data, emphasizing the need for relevant urban management organizations to develop such data. [ABSTRACT FROM AUTHOR]

This study quantified how a smart rainwater harvesting cistern that collected stormwater runoff from a green roof reduced stormwater flow into a combined sewer system (CSS) during wet-weather flow. The studied smart rainwater harvesting cistern collected runoff from a green roof located in Bronx, New York City; it used the Continuous Monitoring and Adaptive Control (CMAC) smart sensor provided by OptiRTC, Inc., to regulate the water flow from the cistern. The cistern collected stormwater runoff from the roof, usually draining completely after 24 h of dry weather. However, the smart sensor used weather forecasting data, and if additional rainfall was predicted immediately following another storm, the cistern only drained a specific amount, calibrated to mitigate the CSO. Five years of data from the cistern system were used to understand the role of the cistern's smart sensor in reducing stormwater flow into the CSS during storms. The study results demonstrate that connecting the smart cistern system to the green-roof maximized stormwater collection (compared with the green roof alone) for storm sizes between 2 mm and 25 mm and for antecedent dry-weather periods greater than 2 days. The total of 65.2% of rainfall retained over the monitoring period by the green roof alone increased to 75.6% when considering the total stormwater retained and detained together by the green roof and cistern, thus yielding a 10% improvement. The study results also demonstrate that the smart sensor's use of weather forecasting data failed to improve system performance. [ABSTRACT FROM AUTHOR]

In a water-scarce country such as Pakistan, rainfall is the third-largest source of freshwater. In most of the urban cities of the country, rainwater is mixed with sewerage and is rendered useless for managed aquifer recharge purposes. Therefore, this study investigates the rainfall potential for managed aquifer recharge in Lahore (Pakistan). The present research was designed and conducted by the Irrigation Research Institute (IRI). Three different sites were selected for rainwater sample collection across the study area (Lahore), ranging from urban to rural areas. The rainwater samples were collected and divided into three categories (direct capture, rooftop runoff, street runoff). For longer rainfall events, the effect of time on the quality of the collected rainwater samples was also studied. Spatiotemporal trends of turbidity, pH, electrical conductivity, total dissolved solids, carbonates, bicarbonates, chloride, calcium, magnesium, and hardness in the collected rainwater samples were investigated. In terms of TDS, results indicated that directly captured rainwater is most suitable for managed aquifer recharge (TDS < 50 ppm), followed by rooftop runoff (TDS < 100 ppm). In addition, the quality of rainwater samples collected at the rural site was comparatively better. Moreover, the quality of rainwater samples improved after the initial ten minutes. All in all, this study concludes that direct capture of rainwater is the most suitable option for managed aquifer recharge. [ABSTRACT FROM AUTHOR]

Rainwater harvesting is an ancient technique to irrigate agriculture land in arid and semi-arid regions. Kirthar mountain range, Sindh Pakistan, receives an average annual rainfall of 250 mm, mainly during monsoon season from June to September, which is used to irrigate the agricultural land. Rainwater is also stored by local farmers in the form of small ponds which is not sufficient to fulfill agricultural requirements throughout the year. Rainwater storage structures like irrigation dams can be used to augment water supplies in the agricultural areas. Therefore, the objective of this study is to identify potential sites for rainwater storage. For this, the understanding of spatial and temporal patterns of rainfall is important factor for annual run off estimation. Due to scarcity of weather station in the county, both the gauge data of Dadu station and satellite estimates were used to determine annual rainfall runoff using soil conservation service curve number (SCS-CN) method. Analytic Hierarchy Process (AHP) was employed to calculate the relative importance of different spatially varying parameters like geology, runoff potential, landuse/ land cover, stream network, settlement and slope. Then the relative percentage weights of each influencing factors were processed using weighted overlay analysis to identify potential sites. The analysis identified five, the most suitable sites for rainwater storage structure. Out of these five sites, site-3 is already under construction which validates the findings. The study showed strong potential of building water storage structure to store rainwater during intense rainfall events in monsoon. Subsequently these structures can help to increase gross productivity of agriculture as well as to enhance the socioeconomic status of the local community and farmers living in nearby villages [ABSTRACT FROM AUTHOR]

Copyright of Al-Adab / Al-ādāb is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)