Main Source Of Water Research Articles

Design and Analysis of Water Distribution System Network for a Rural Area of Gujarat State by Using EPANET

Abstract: This study presents the use of EPANET software in the design of the water distribution network for Vadi village in Umarpada District, Gujarat State. The major purpose of providing a good distribution network is to provide sufficient pressure at each point with less loss. A water distribution network consists of pipes, tanks etc. EPANET software is simulation tool which is used for efficient distribution of water supply. For the analysis of existing water distribution system various data are required like, Main water source, Population of the area, Demand for water, Requirement of the pumps, Distribution Network, and water tanks. The Google Earth Image of Vadi village is downloaded and the elevation of a node, length of pipe was recorded for nearly 112 junctions and 114 pipes.

Inaccessible and Unaffordable? The State of Water and Sanitation Services in Nairobi, Kenya

As the limited water resources become increasingly stressed by factors such as rapid urbanization, population growth, and climate change, the need for sustainable urban water management is more important than in the past decades. A large part of the world’s population still lacks access to clean water and sanitation, making achieving Sustainable Development Goals a challenge. Water is an indispensable resource and plays an important role in ensuring the achievement of Sustainable Development Goals. Therefore, there is a need to prioritize research on the availability, affordability, and access of water resources to promote sustainable water resource management. In this study, we reviewed academic articles and published reports from various institutions and organizations to assess water sources, infrastructure, coverage, accessibility, and affordability of water and sanitation services in Nairobi County. The study identified Nairobi’s main water sources as municipal water, primarily from surface water and groundwater. However, the capacities of the water sources, treatment plants, and wastewater treatment plants were found to be insufficient, resulting in water shortages in most parts of the city.Most of the infrastructures were also found to be insufficient and old, contributing to water distribution inefficiencies, frequent leakages, and pipe bursts which hampers water reliability. The study suggests prioritizing the water and sanitation sector in government budgets to increase infrastructure development investments and funding. Appropriate wastewater treatment methods should also be adopted and implemented to enable wastewater to meet water consumption standards and be potentially integrated into supply systems.

Quaternary tectonic and climatic forcing on the spatio-temporal evolution of the Meuse fluvial terrace staircase

The Quaternary is characterized by pronounced alterations between cold and warm climatic states, with the Mid-Pleistocene Transition marking a strong increase in the intensity of cold-climate conditions. River systems are sensitive to environmental perturbation (e.g., climate, tectonics, base level) and are expected to respond to such profound changes. This study uses a combination of terrace mapping and analysis of a dense borehole database to investigate the Meuse terrace staircase (and its deposits), and gain insight on how it reflects climatic and tectonic perturbations during the Quaternary. The lower reaches of the Meuse river, which has both its main water and sediment source in the Ardennes displays a well-developed terrace staircase that was sculpted mainly throughout the Quaternary. The staircase is located near the cities of Maastricht (southern Netherlands) and Liège (northwestern Belgium). About 30 terrace levels reflect signals of environmental perturbations in the lithological composition, gradients, thicknesses, and spatial distribution. The terraces are organized in groups, based on their morphological position, from old to young; these are the East Meuse terrace group and West Meuse High-, Middle- and Low terrace groups. Our findings show a consistent increase in the gravel content from older to younger terraces. The sandier composition of the deposits of the oldest terraces (Early Pleistocene) is closely related to the supply of the Miocene-Pliocene weathered material from the Ardennes. Younger terraces (Middle and Late Pleistocene) are much richer in gravel, evidencing sediment input from fresh or partially weathered bedrock. These changes point to a downstream migration of the gravel front throughout the Quaternary. The mean thickness of the terrace groups shows a slight increase, even though the same trend is not clear when each terrace is analyzed on an individual basis. The anomalous thickness of the Caberg 1 terrace suggests increased sediment input during the cold climatic conditions of the Elsterian (MIS 12), the first Quaternary glacial during which an ice sheet extended into the northern Netherlands. Reconstruction of terrace gradients reveals that older East Meuse terraces show a (reversed) gradient opposite to reconstructed palaeo flow directions, which is attributed to a combination of low gradients during terrace formation and footwall back-tilting of the Feldbiss Fault Zone. In our analysis we do not see clear evidence for the imprint of the Mid-Pleistocene Transition, which suggests that due to its gradual nature, its signal is either buffered or assimilated by the overall climatic signal of the Quaternary. This study offers a first complete temporal analysis of the Meuse terrace staircase, providing an important basis for better understanding the effects of Quaternary climatic change and tectonics, and their resulting effects in other river systems worldwide.

Developing a Bankruptcy Theory to Resolve Stakeholders’ Conflict over Optimal Water Allocation: The Case of Hirmand Catchment

The growing increase in demand for water and the lack of balance between water supply and demand have led to conflicts among the downstream stakeholders of the international Hirmand River. This river is shared between Iran and Afghanistan and is located in the southeast of Iran, in the Sistan region. The Vardkhaneh is divided into two branches, Parian and Sistan, and it is the only main source of water in the Sistan region of Iran. The inner part of Hirmand catchment is considered bankrupt concerning its water resources, so there is a need to take the current status and resulting issues into account in order to resolve conflicts. In Hirmand catchment, four different games of bankruptcy theory, namely proportional (Pr), adjusted proportional (AP), constrained equal award (CEA), and constrained equal losses (CEL), were developed as optimization models based on genetic algorithms. For this purpose, the catchment was simulated with 26 scenarios using the WEAP 2022 version software for an average time period. The results of the bankruptcy game modeling showed that water could be effectively allocated to resolve conflicts among stakeholders. It is therefore recommended to use such a model to resolve fights and optimally allocate resources, even in bankrupt catchments.

An accurate snow cover product for the Moroccan Atlas Mountains: Optimization of the MODIS NDSI index threshold and development of snow fraction estimation models

In semi-arid Mediterranean areas, a significant proportion of the population living downstream depends on water resources from snowmelt and precipitation as their main source of water. Consequently, snow-covered mountain regions can be considered as a vital water tower, providing a steady supply of water, and contributing significantly to streamflow and groundwater recharge. Given the scarcity of ground-based hydroclimatic measurements, remote sensing could be an effective technique for mapping and monitoring snow cover. This study evaluates the last version of MODIS (version 6, called V6) snow cover product, optimizing the NDSI threshold for accurate snow cover mapping and developing models for local fractional snow cover estimation in the southern Mediterranean region, particularly in the Moroccan Atlas Mountains. For this purpose, 448 Sentinel-2 (S2) scenes from six different regions across the Atlas Range were used to adjust the NDSI threshold and to develop FSC estimation models. In addition, a total of 8419 MOD10A1 images from March 2000 to June 2023, and 7561 MYD10A1 images from September 2002 to June 2023, were processed to improve cloud filtering and to develop a highly accurate daily snow cover product suitable for the Moroccan Atlas Mountains. The cloud correction approach significantly reduced the number of cloud-covered pixels, from 25.7% to 0.4% after filtering. Two schemes for selecting the MODIS NDSI threshold were tested: (1) the global reference of 0.4 and (2) the locally optimal threshold of 0.2. The average snow cover estimation errors using the optimal and global NDSI thresholds for Terra are an average overestimation of 0.34% and a significant underestimation of 6.13%, respectively. For Aqua, the corresponding errors are an overestimation of 1.4% and an underestimation of 6.8%. Thus, the optimal NDSI threshold of 0.2 could be more appropriate than the threshold of 0.4 for use in the southern Mediterranean region. The new FSC estimation models developed showed satisfactory performance with significant correlation coefficients (mean of 0.85 for Terra and 0.83 for Aqua), and with low RMSE and MAE values (mean of 0.17 and 0.12 for Terra and mean of 0.19 and 0.14 for Aqua) when comparing FSC derived from high-resolution S2 data with predicted FSC from MODIS NDSI. The daily snow cover product developed was compared with the high-resolution snow maps obtained from S2 satellite imagery in different regions of the Moroccan Atlas. On average, the product showed a mean correlation coefficient of 0.96, a mean absolute error of 0.22%, and a mean reasonable negative bias of −0.17%. This research concludes that the enhanced daily snow cover product could improve the understanding of spatiotemporal dynamics of snow extent and, therefore, contribute to quantifying the snowmelt contribution to the water budget through modeling approaches in the southern Mediterranean region.

Effects of a rainwater harvesting system on the soil water, heat and growth of apricot in rain-fed orchards on the Loess Plateau

Rainwater is the main water source in arid and semiarid areas of the Loess Plateau, where rainfall is generally insufficient, ineffective and underutilized during the growing season. Thus, improving rainwater utilization efficiency is essential for sustainable agricultural development. A new system composed of rainwater harvesting, an infiltrator bucket with multiple holes and mulching (RHM), was designed to maintain soil moisture at a proper level in rain-fed orchards in arid and semiarid areas of the Loess Region of China. However, there is a lack of clarity on the effectiveness of RHM. In this study, changes in the soil environment and the growth and physiology of apricot trees were monitored via two treatments: (1) Rain-harvesting irrigation system (RHM) treatment and (2) traditional orchard treatment (CK) as a baseline. The results showed that (1) RHM could effectively improve soil water storage at depths of 0–45 cm and at a horizontal distance of 40 cm from the trunk. For the 1.4 mm light rain event, the soil water content increased by 6.3–12%, and for the two moderate rains, the soil water content increased by 12–25%. The change in the soil relative water content predicted by the LSTM model is consistent with the overall trend of the measured value and gradually decreases, and the prediction accuracy is high, with an error of 0.65. (2) The average soil temperatures at 5 cm, 20 cm and 40 cm under RHM were 17.0% (2.4 °C), 13.6% (1.9 °C) and 7.5% (1 °C) greater than those under CK, respectively. (3) Compared with the control treatment, RHM improved the growth and WUEL of apricot trees. The results highlighted the efficiency of the RHM system in enhancing the soil environment and regulating the growth and physiology of apricot trees, which has greater popularization value in arid and semiarid areas.

Pilot studies for the application of triple media filtration at Morton Jaffray Water Works, Harare, Zimbabwe

Abstract Lake Chivero, Harare's main source of raw water for drinking water, is algae infested thus affecting water treatment processes at Morton Jaffray Water Treatment Works (MJWTW). Consequently, several challenges have been encountered including frequent filter backwashing, leading to a reduced plant output. In this study, the potential of substituting single-media filters (currently used at MJWTW) with triple-media filters was investigated. This was done using pilot filters of a single-media filter (SMF) and a triple-media filter (TMF) and piloted using clarified water from MJWTW. Electrical conductivity (EC), pH, total dissolved solids (TDS), turbidity, and temperature were the water quality parameters that were monitored. Headloss and flow rate were the filter operation parameters that were monitored. Both water quality and operational parameters were monitored at hourly intervals until one filter reached the maximum allowable headloss or turbidity limit. The variation in effluent turbidity, TDS, EC, and pH between the filters was insignificant. Nevertheless, the headloss development for the TMF was significantly slower than that of the SMF resulting in the SMF reaching the maximum headloss earlier. Therefore, the TMF performed better overall. Therefore, the adoption of TMF could result in a longer filter run and improve filtration and water production at MJWTW.

Numerical Analysis of Soil Deformation in Earth Dams Using a Stiffness Variation Technique

Small earth dams have been used since ancient times and are often the main source of water in semi-arid regions. In this particular type of engineering work, soils saturated by water present changes in their mechanical properties (especially in the first filling), which usually cause a simultaneous loss of stiffness and shear strength. In this context, the software UNSTRUCT presents itself as a very useful tool, as it allows calculating the final state of stress x strain for a plane strain state, using the Finite Element Method, both for saturated and unsaturated embankments, considering an elastic model and the effect of suction (and its variation), through a stiffness variation technique. The present research used UNSTRUCT to assess the behavior of the embankment of a hypothetical earth dam, varying the features of its typical cross-section: homogeneity; internal drainage structures; geometry along a longitudinal profile; and the influence of the compaction level. The results showed that the soil responded better to strains for the scenario of better compaction along the dry branch of the compaction curve, as well as with the use of a vertical drainage element. It was also observed that the strains were higher when greater sections considered, which, in a real situation, would cause distortions along the longitudinal profile of the dam. The software UNSTRUCT proved to be efficient in obtaining and visualizing the modeling results, also making it possible to analyze the development of failure over time after the dam was filled. With UNSTRUCT, a more realistic analysis of the behavior of the hypothetical dam – considering factors that are specific to unsaturated soils – was possible. Worth mentioning also that the software allowed the appraisal of multiple changes in the dam’s geometry and parameters.

The Dynamics of the Concentration and Speciation of Arsenic in Private Drinking Water Wells in Eastern Wisconsin, USA

About 2.5 billion people rely on groundwater as their main drinking water source, and arsenic pollution within the groundwater system can cause serious short- and long-term health issues. Within the natural environment, arsenic generally exists as oxyanions which have two oxidation states, As(III) and As(V). Under ambient pH conditions, As(V) is primarily present as an anion (i.e., H2AsO4−) while As(III) tends to be uncharged (i.e., H3AsO3), making it much more difficult to remove As(III) through existing treatment techniques such as adsorption and reverse osmosis (RO). In Eastern Wisconsin, the dolomite and dolomite/sandstone aquifers represent a major drinking water source and high arsenic concentrations have been observed. Previous studies showed that arsenic can be released into private drinking water wells due to the oxidation of sulfide-bearing minerals with arsenic impurities that are usually dispersed within the dolomite and sandstone bedrock. However, there is a lack of information on the concentrations of each arsenic species as well as arsenic dynamics during water pumping/usage. The primary goals of this research were (1) to quantify the baseline concentrations of each arsenic species within selected Eastern Wisconsin private drinking water wells, and (2) to determine how the arsenic concentrations and species could be affected by continuous water usage. Our results showed that As(III) was the dominant species of arsenic, and during continuous water usage, there could be an upward trend in arsenic concentration (there was minimal change in arsenic speciation). Upon the completion of water pumping, arsenic concentrations decreased over time and returned to pre-pumping levels. Our findings highlighted the importance of quantifying the speciation and dynamics of arsenic during water use to the assessment of public health risks and the design of appropriate water treatment techniques.

PEMODELAN KUALITAS AIR TANAH OLEH AIR LIMBAH DOMESTIK MENGGUNAKAN ARCGIS DI DESA KERTALANGU

<p><em>The community living in Kesiman Kertalangu Village, East Denpasar, Denpasar City, Bali, has a few open shallow wells at home. Well water is used for daily activities such as washing, washing vehicles, and watering plants. The main source of water is groundwater, which is found in rocks below the earth's surface. The availability and movement of groundwater depends on the geological conditions of the area.</em><em> </em><em>Groundwater that is used as a source of community life must meet good water quality, so the purpose of this study was to determine the condition of groundwater during the study. The samples used for groundwater testing were 30 wells spread across this village. The methods used were interviews with the local community, field testing of well water samples (smell and temperature tests), laboratory tests (pH, TSS, TDS, DHL and microbiology) and modeling analysis of all research data results using the ARCGIS application. The research results obtained were field tests such as odor tests and temperature tests that passed the clean water requirements because they met the standards set by the Ministry of Health. laboratory tests such as the TDS, TSS and DHL tests have met the requirements as clean water because the number of solid particles dissolved in water and gas is below the specified limits, and the amount of suspended solids in water is also below the limits. Microbiological test results showed that several points were quite polluted by E.Coli and Total Coliform bacteria caused by the distance between the well points and the septic tank in people's homes.</em></p>

Assessment of Groundwater Quality of Taluka Bulri Shah Karim, District Tando Muhammad Khan, Sindh, Pakistan

Groundwater in Pakistan is the main drinking water source, highlighting the significance of regularlymonitoring its quality. There have been several examples of high concentrations of elements like arsenic and nitrate ingroundwater that harm human health and the environment. Our aim with this study was to assess the groundwater qualityof the sub-district Bhulri Shah Karim for drinking and irrigation purposes. We collected groundwater samples from 53shallow bore well hand pumps in October and November 2018. We determined the concentration of four cations, fiveanions and other parameters like pH, turbidity, TDS, total hardness, EC, alkalinity, total iron, and arsenic. Thegroundwater was found to be very hard, and the relative abundance of cations and anions was Na+> Ca2+> Mg2+> K+ andCl‾ > HCO3‾ > SO42‾ > NO3‾ > F‾. The concentrations of arsenic and iron varied from 0 to 0.2 mg/L and 0.02 to 3.6mg/L, respectively. We discussed groundwater quality for drinking and irrigation purposes by calculating the waterquality index, sodium adsorption ratio, percent of sodium, permeability index, and residual sodium carbonate. Inconclusion, the groundwater of the studied area is suitable for drinking on average and irrigation. However, some watersamples were high in arsenic content, and some were highly saline and may need some prior treatment

Characteristics of Runoff Components in the Mingyong Glacier Basin, Meili Snow Mountains

As an important hydrological ecosystem component, the glacier basin has great significance for climate and environment, and it is also linked to regional water sustainability. In this paper, the sampling and isotope analysis of glacial ice, ice-melt water, river water (river midstream and river downstream), groundwater (spring), and precipitation were carried out in a hydrological year of the Mingyong Glacier basin, which is located at the Meili Snow Mountains, Southeastern Tibetan Plateau. At the same time, the hydrograph separation of the recharge sources of the lower mountain pass is studied. The results show that the range of δD, δ18O, and d-excess (deuterium excess) in natural water bodies are significantly different, and the precipitation is the most obvious. The high values of δD and δ18O in the water samples all appeared in spring and summer, and the low values appeared in autumn and winter, while glacial ice showed opposite trends. Meanwhile, the local meteoric water line (LMWL) of the Mingyong Glacier basin is δD = 8.04δ18O + 13.06. The End-Member Mixing Analysis (EMMA) was adopted to determine the sources proportion of river water (river downstream) according to the δD, δ18O, and d-excess ratio relationships. The results showed that the proportion of ice-melt water, groundwater, and precipitation in the ablation period was 80.6%, 17.2%, and 2.2% as well as 19.2%, 73.1%, and 7.7% in the accumulation period, respectively. Ice-melt water has a higher conversion recharge rate to groundwater and indirectly recharges river water, especially in nonmonsoon seasons. In other words, the main recharge source of river water in the lower reaches of the Mingyong Glacier basin during the ablation period is ice-melt water. In the accumulation period, the main recharge source of river water in the lower reaches of the Mingyong Glacier basin is groundwater, while nearly half of the recharge of groundwater comes from ice-melt water. Therefore, regardless of the ablation period or the accumulation period, ice-melt water is sustainable and important to this region.

ANALISIS NERACA AIR DI TITIK BENDUNG TEMPANG DAERAH IRIGASI PANASEN HULU KABUPATEN MINAHASA

This study aims to conduct a water balance analysis at the Tempang weir point, which is part of the Panasen Hulu Irrigation Area in Minahasa Regency. The Panasen River is the main source of water to meet the irrigation needs in this area. Given the complexity of the dry season period which is difficult to predict, water balance analysis needs to be carried out to calculate the availability and demand of water in the Upper Panasen Irrigation Area, to improve the optimization of water resource management of the Panasen River. Water balance analysis is carried out by calculating the ratio between water availability and water demand. To calculate water availability, the NRECA Modified method is used with available data, namely rainfall data, evapotranspiration, and watershed parameters to calculate the mainstay discharge Q80% and water availability for maintenance of the Q95% River. The calculated water needs are for water needs in the Upper Panasen Irrigation Area. The results of the water balance analysis show periods of water deficit in which water demand exceeds water availability, causing difficulties in meeting irrigation needs. However, there are also periods of surplus water that can be utilized for more effective management of water resources.

ANALYSIS OF HOUSEHOLDS’ WILLINGNESS TO PAY FOR THE PROVISION OF PDAM TIRTA RAHARJA’S PIPE CONNECTION USING CONTINGENT VALUATION METHOD

Gandasari is one of the villages in Katapang Sub District, Bandung Regency. Most people in Gandasari Village use groundwater as their main water source to fulfill their needs of water. Groundwater in Gandasari Village has bad quality and quantity. Hence, the provision of a safe water supply is needed in Gandasari Village. On the other hand, Perusahaan Daerah Air Minum (PDAM) Tirta Raharja is developing their House Connection (SR) in Gandasari Village RW 5,6,7,9, and 11. Provision and management of water supply required to achieve full cost recovery. Therefore, it is necessary to know the willingness to pay (WTP) value for the provision of PDAM’s pipe connection. This study aimed to determine households’ WTP for the provision of piped water service and identify the factors affecting it. The WTP was estimated through questionnaires collected from 89 households in Gandasari Village using Contingent Valuation Method (CVM) and bidding games technique. Based on the questionnaire result, the Estimated Mean WTP (EWTP) value of WTP for installation fee is Rp961.798 and Total WTP is Rp735.775.281. Meanwhile the EWTP value of WTP for retribution fee is Rp51.180/month and TWTP is Rp39.152.528. Factors affecting the value of WTP for installation fee is household size and average income, meanwhile for retribution fee WTP value average income was the affecting factor. Provision of communal well is recommended for households who cannot afford to pay for PDAM.

Hydrochemical Characteristics and Control Factors of Shallow Groundwater in Anqing Section of the Yangtze River Basin

Shallow groundwater is the main source of water for living and industrial and agricultural production in Anqing City, which is an important basic guarantee to maintain the sustainable development of the social economy and regional ecological environment. In order to further study the water chemical characteristics and controlling factors of shallow groundwater in Anqing City, 196 groups of shallow groundwater samples were collected. A Piper diagram graph, Gibbs chart, ion ratio, and mathematical statistics were comprehensively used to study the water chemical characteristics and controlling factors of groundwater in Anqing City, and the contribution of different sources to the water chemical components of groundwater was quantitatively evaluated. The results showed that the shallow groundwater in Anqing City was weakly alkaline, with pH values ranging from 5.84 to 8.38, with an average value of 7.21. The TDS ranged from 47 to 1 620 mg·L-1, with an average of 324.21 mg·L-1. HCO3- and Ca2+ were the main anions, and the water chemical type was HCO3-Ca type. The chemical components of groundwater were affected by rock weathering leaching, cation alternating adsorption, mineral dissolution and precipitation, and human activities. Ca2+, Mg2+, and HCO3- were mainly derived from the weathering dissolution of carbonate and silicate; Na+, Cl-, and SO42- were affected by industrial activities and domestic sewage discharge; and K+ and NO3- were affected by agricultural activities. The APCS-MLR receptor model analysis further revealed that the chemical components of groundwater were mainly geological factors, industrial factors, agricultural factors, and unknown sources, and their contribution rates were 45.35%, 14.19%, 25.38%, and 15.08%, respectively. Geological factors were important sources of hydrochemical components of shallow groundwater, and human activities aggravated the evolution of groundwater hydrochemistry.

HYDROLOGICAL REGIME OF WATER STREAMS AND THE PROBLEMS OF PUBLIC WATER SUPPLY IN THE REPUBLIC OF KALMYKIA

The constant shortage of fresh water for drinking and municipal use in the Republic of Kalmykia has become critically acute recently. Both natural factors, i.e. increasing climate aridity, limited reserves of fresh surface and groundwater, lack of sufficiently long sections of large rivers with constant flow, and the deterioration of hydraulic structures are the reasons. The exploitation of groundwater in existing deposits has led to their depletion and deterioration, while large deposits of fresh and slightly brackish groundwater in the southern Caspian region cannot be used because the content of pollutants in them is rather high. Recovery of old and construction of new water pipelines from the Volga River requires permanent significant financial investments at the federal level. Therefore, recently a new way to increase the supply of fresh water suitable for drinking purposes, i.e. an artificial groundwater recharge (AGR), has been actively discussed. The article provides an actual assessment of water resources of the littlestudied surface runoff of the rivers of Kalmykia, considers the possibility and feasibility of creating infiltration basins to replenish groundwater reserves, and calculates the parameters and operating mode of five planned basins. The main source of fresh surface water in Kalmykia is the rivers of the Ergeni Upland. The average long-term flow from its eastern slope is estimated at 0,120 km3/year, from the western slope at 0,105 km3/year and from the southern slope at 0,045 km3/year. Trends in modern modification of the hydrological regime of rivers under the influence of climate change have been revealed, namely a decrease in annual runoff and its intra-annual redistribution with a reduction of spring floods, a slight increase in winter runoff and a leveling of summer low-water periods. Calculation of the operating mode of planned infiltration basins allowed us to draw the following conclusions: the maximum possible volume of total infiltration will be about 220 thousand m3/year, which is 36 times less than the presentday water intake from the Troitsk and Bayarninsky fields for public water supply; sufficiently efficient operation of pools is only possible with annual cleaning of accumulated silt deposits, otherwise the soil filtration coefficient will come down each year, resulting in the reduction of infiltration supply by dozens times. Thus, the AGR can only be a temporary measure to compensate for the subsidence of groundwater level until the reconstruction and construction of new water pipelines from the Volga River to supply the city of Elista and the surrounding area with drinking water of acceptable quality

Study of the Operating Cost of the Electric Pump for Mine Dewatering: Case of the SOMAÏR Uranium Mine

This study focuses on the operating cost of the electric pump used to extract water from the Artois mine owned by Société des Mines de l'AÏR. Exploitation of the SOMAÏR Artois mine uranium deposit is to be increased from the 20 m level to the 80, 100 or 120 m level; in the current phase of certain pits, access to the uranium deposit can only be achieved by a means that can draw off the water encountered. It is therefore essential to set up a drainage system to manage and evacuate the various water inflows. The main source of incoming water is the nearby water table, which is drained directly onto the mining unit. The current drainage system has two sumps capable of storing the various water inflows without incident. The energy balance for the three (3) years of pumping was drawn up using the electricity consumption data received. Peaks appear in August for the year 2021, followed by January 2020 and May 2022. The results show that specific energy is high, resulting in higher power consumption than water production. According to the graph of performance curves P = f(Q), the power ratings obtained for flows corresponding to the 24 m head are 25 kW at a flow rate Q = 49 l/s for pump 261; 35 kW, at a flow rate Q = 59 l/s for pump 259 and 35 kW at a flow rate Q = 105 l/s for pump 234.

Groundwater vulnerability zonation using Aplis and Foster method in The Ponorogo-Ngawi groundwater basin

In 2021, Ngawi district became the largest rice producer in East Java. Groundwater is the main water source used for irrigation purposes. Lack of management for developing necessary irrigation wells has resulted in uncontrolled groundwater use, potentially reducing groundwater quantity and quality. This study aims to analyze groundwater vulnerability zones. An assessment was conducted using the Aplis and Foster methods, and their parameter classes can be customized to match the conditions of the research area. The Aplis method considers five parameters: altitude (A), slope (P), lithology (L), infiltration (I), and soil (S). The Foster method considers four parameters: aquifer response characteristics (RA), aquifer storage characteristics (DS), aquifer thickness (s), and groundwater depth (h). The vulnerability values obtained using the Aplis method ranged from 30 to 131 and were divided into four classes: low, moderate, high, and very high. The Vulnerability values obtained using the Foster method ranged from 10 to 15 for the low and moderate classes. A non-technical approach through the strict application of permits and restrictions on groundwater usage is a basis for formulating policies related to groundwater management in the research area.

One to twelve-month-ahead forecasting of MODIS-derived Qinghai Lake area, using neuro-fuzzy system hybridized by firefly optimization.

Lakes, as the main sources of surface water, are of great environmental and ecological importance and largely affect the climatic conditions of the surrounding areas. Lake area fluctuations are very effective on plant and animal biodiversity in the areas covered. Hence, accurate and reliable forecasts of ​lake area might provide the awareness of water and climate resources and the survival of various species dependent on area fluctuations. Using machine learning methods, the current study numerically predicted area fluctuations of ​China's largest lake, Qinghai, over 1 to 12months ahead of lead time. To this end, Moderate Resolution Imaging Spectroradiometer (MODIS) sensor images were used to monitor the monthly changes in the area of ​the lake from 2000 to 2021. Predictive inputs included the MODIS-derived lake area time latency specified by the autocorrelation function. The data was divided into two periods of the train (initial 75%) and test (final 25%), and the input combinations were arranged so that the model in the test period could be used to predict 12 scenarios, including forecast horizons for the next 1 to 12months. The adaptive neuro-fuzzy inference system (ANFIS) was utilized as a predictive model. The firefly algorithm (FA) was also used to optimize ANFIS and improve its accuracy, as a hybrid model ANFIS-FA. Based on evaluation criteria such as root mean square error (RMSE) (477-594 km2) and R2 (88-92%), the results confirmed the acceptable accuracy of the models in all forecast horizons, even long-term horizons (10months, 11months, and 12months). Based on the normalized RMSE criterion (0.095-0.125), the models' performance was reported to be appropriate. Furthermore, the firefly algorithm improved the prediction accuracy of the ANFIS model by an average of 16.9%. In the inter-month survey, the models had fewer forecast errors in the dry months (February-March) than in the wet months (October-November). Using the current method can provide remarkable information about the future state of lakes, which is very important for managers and planners of water resources, environment, and natural ecosystems. According to the results, the current approach is satisfactory in predicting MODIS-derived fluctuations of Qinghai Lake area and has research value for other lakes.

Ensemble projections of climate and streamflow in a typical basin of semi-arid steppes in Mongolian Plateau of 2021–2100

The Kherlen River is the main water source for Hulun Lake, the largest lake in northern China. Due to reduced inflow from the Kherlen River, Hulun Lake experienced rapid shrinkage at the beginning of the 21st century, posing a serious threat to the ecological security of northern China. However, there is still a significant lack of projections regarding future climate change and its hydrological response in the Kherlen River basin. This study analyzed the projected climate and streamflow changes in the Kherlen River basin, a vital yet vulnerable international semi-arid steppes type basin. A combination of multi-model ensemble projection techniques, and the soil and water assessment tool (SWAT) model was employed to examine the spatio‒temporal changes in precipitation, temperature, streamflow, and the associated uncertainties in the basin. The temperature (an increase of 1.84–6.42 °C) and the precipitation (an increase of 15.0–46.0 mm) of Kherlen River basin are projected to increase by 2100, leading to a rise in streamflow (1.08–4.78 m3 s−1). The upstream of the Kherlen River exhibits remarkable increasing trends in precipitation, which has a dominant influence on streamflow of Kherlen River. Noteworthy increases in streamflow are observed in April, August, September, and October compared to the reference period (1971–2000). These findings suggest a partial alleviation of water scarcity in the Kherlen River, but also an increased likelihood of hydrological extreme events. The projected temperature increase in the Kherlen River basin exhibits the smallest uncertainty, while more pronounced uncertainties are found in precipitation and streamflow. The spread among the results of CMIP6 models is greater than that of CMIP5 models, with lower signal-to-noise ratio (SNR) values for temperature, precipitation, and streamflow.