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This study is an exploratory examination of the effect of the Ghana government's flagship program known as the One-Village-One-Dam (1V1D) initiative on the livelihoods of rural farmers in the five regions of Northern Ghana. A total of 15 constituencies proportionate to the number of constituencies in each of the five beneficiary regions were selected from the region. Data were collected from a total of 1585 respondents, comprising 785 from the control group and 800 from the treatment group. The survey focused on access to water, crop and livestock productivity, income generation, and overall well-being. Four main findings are reported. First, the results show differential effects of the 1V1D initiative. There was an increase in reliance on 1V1D dams for water, particularly in the Northern region, where challenges such as insufficient water storage and poor dam maintenance hindered their effectiveness for irrigation and livestock rearing. Second, the use of water from boreholes was more popular in the other parts of Northern Ghana. Third, the shallowness of most of the dams meant that they dried up during the dry season and, therefore, did not have a significant effect on crops and livestock productivity. Finally, the dams had a marginal effect on food security, income levels of the farmers, and consequently on their overall livelihoods. The findings of this exploratory study will provide insights to enrich further studies based on the second and third rounds of data collection. [ABSTRACT FROM AUTHOR]

In recent years, the global energy sector has seen significant transformation, particularly in Europe, with a notable increase in intermittent renewable energy integration. Italy and the European Union (EU) have been among the leaders in this transition, with renewables playing a substantial role in electricity generation as of the mid-2020s. The adoption of Battery Energy Storage Systems (BESS) has become crucial for enhancing grid efficiency, sustainability, and reliability by addressing intermittent renewable sources. This paper investigates the feasibility and economic viability of batteries in wholesale electricity markets as per EU regulation, focusing on the dynamics of very different markets, namely the Day-Ahead Market (DAM) based on system marginal price and the Cross-Border Intra-day Market (XBID) based on continuous trading. A novel model is proposed to enhance BESS operations, leveraging price arbitrage strategies based on zonal price predictions, levelized cost of storage (LCOS), and uncertain bid acceptance in continuous trading. Machine learning and deep learning techniques are applied for price forecasting and bid acceptance prediction, respectively. This study finds that data-driven techniques outperform reference models in price forecasting and bid acceptance prediction (+7–14% accuracy). Regarding market dynamics, this study reveals higher competitiveness in the continuous market compared to the DAM, particularly with increased risk factors in bids leading to higher profits. This research provides insights into compatibility between continuous markets and BESS, showing substantial improvements in economic profitability and the correlation between risk and profits in the bidding strategy (EUR +9 M yearly revenues are obtained with strategic behavior that reduces awarded energy by 60%). [ABSTRACT FROM AUTHOR]

Throughout history, the implementation of structural health monitoring systems has played a crucial role in evaluating the responses of dams to environmental and human-induced threats. By continuously monitoring structural integrity and analyzing dynamic characteristics, these systems offer a robust alternative to traditional visual inspection methods, ensuring the long-term safety of dams. This paper delves into the intricate process of operational modal analysis applied to dams, encompassing data collection, preprocessing, and the utilization of diverse modal identification techniques across both time and frequency domains. Moreover, it explores innovative approaches aimed at overcoming challenges encountered in previous methodologies. Also, the evolution of automated modal identification techniques and their application in dams are investigated. It explores the advancements in this field and their implications for enhancing the efficiency and accuracy of modal analysis processes. Furthermore, this paper evaluates the effectiveness of damage detection methods in dams based on operational modal identification. [ABSTRACT FROM AUTHOR]

The Chesapeake Logperch, Percina bimaculata, is a small fish endemic to the upper Chesapeake Bay drainage with a range significantly reduced by water quality and habitat degradation. It was described by Haldeman in 1842 and 1844 from the Susquehanna River, Pennsylvania, synonymized with the Logperch (Percina caprodes) by Jordan in 1877, and redescribed by Near in 2008. It is extirpated from the Potomac River drainage and extant in a portion of its historic range within the Susquehanna River drainage of Pennsylvania and Maryland in the United States of America. We reviewed available historic field survey information and defined the likely extent of the historic distribution of P. bimaculata and its change in response to historic environmental perturbations. We performed fisheries surveys during 2004–2023 to fill data gaps and to define the current distribution and abundance in the Susquehanna River drainage within Pennsylvania. Our surveys utilized electrofishing gears, electrified benthic trawls, and seines. Our surveys targeting P. bimaculata on the Susquehanna River and tributaries from York Haven to Holtwood, Pennsylvania, combined with available fisheries surveys conducted by others, confirm it was extirpated from that portion of the drainage. We documented the continued usage of Conowingo Pond, Susquehanna River, and tributaries below Holtwood by populations known to exist in historic field surveys. These populations appear to have been stable since at least the 1960s based on historic data and our current surveys. We documented previously unknown populations in the Octoraro Creek drainage, Octoraro Reservoir, and Muddy Run Pumped Storage Facility. Habitat utilization observations during our surveys indicate that clean sand, gravel, rubble, boulders, and large woody debris are preferred substrates. In the lower Susquehanna River and two tributaries, P. bimaculata has demonstrated a plasticity of habitat usage by continuing to occur in environments converted into impoundments by dams. In these impoundments, shorelines and connections with clean tributaries containing preferred substrates appear to be important given their utilization by P. bimaculata during our surveys. It is our opinion that the Susquehanna River and tributaries above Holtwood once again constitute suitable habitats. Conservation efforts focused on reintroductions, water quality, habitat, and connectivity have the potential to increase the extent of occurrence, abundance, and security of P. bimaculata. [ABSTRACT FROM AUTHOR]

Transboundary rivers raise critical concerns for state security amidst contemporary ecological strain and regional geopolitics in South Asia. The challenge of 'water security' is underscored by the substantial reliance on transboundary rivers, compounded by the multifaceted impacts of climate change and the simmering geopolitical tensions among riparian nations, especially in the complex dynamics between India–China and India–Pakistan. This study endeavours to illuminate distinctive characteristics of the South Asian transboundary governance framework, wherein rivers are subjected to intensive damming aimed at (a) harnessing hydroelectric potential and (b) leveraging water resources as geopolitical bargaining chips, thereby exerting pressure; however, order is not specified, particularly. In this intricate milieu, international conventions often fail to reconcile internal contradictions inherent within the transboundary governance paradigm. Consequently, transboundary water resources have metamorphosed into an extension of geopolitical realities, embodying intricate interplay between hydrology, geopolitics and state security within the region, especially between China, India and Pakistan. [ABSTRACT FROM AUTHOR]

Convergent estuaries have been shortened by dam‐like structures worldwide. Here, we evaluate 31 long‐term water level stations and use a semi‐analytical tide model to investigate how landward‐funneling and a dam influence tidal and storm surge propagation in the greater Charleston Harbor region, South Carolina, where three rivers meet: the Ashley, Cooper, and Wando. Results show that the phase speed and amplification of the principal tidal harmonic (M2) is larger than other long waves such as storm surge (∼1–4 days) and setup‐setdown (∼4–10 days). Further landward, all waves attenuate, but, as they approach the dam on the Cooper River, a frequency dependent response in amplitude and phase progression occurs. A semi‐analytical tidal model shows that funneling and the presence of a dam amplify tidal waves through wave interference from partial and full reflection, respectively. The different phase progressions of the reflected waves interact with the incident wave to increase or decrease the summed overall wave amplitude. Using a friction‐convergence parameter space, we demonstrate that dominant tides in 23 estuaries and the tidal, storm surge, and setup‐setdown waves in the Cooper River can be delineated into three regimes that describe landward amplification or attenuation associated with funneling, a dam, or both. The regime of each tidal constituent is consistent but can change with the duration and height of each storm surge event; dam associated wave interference can attenuate long‐duration events, while the most intense events (short duration, high water) are amplified by dams more than funneling and greatly increase flood exposure. Plain Language Summary: Most ports and cities are located along estuaries and deltas where flood hazards are increasing partially due to human modifications of channel geometry and land use. Dams, salt barrages, and surge barriers are common in estuaries. They modify estuarine geometry, regulate river flow, protect against flooding, and prevent salt intrusion. Many estuaries are naturally convergent, wide near the sea and narrower landward. Dams are barriers which shorten an estuary. Like ocean swell at a seawall, tides reflect off dams and often increase tidal range. Here we investigate how dams and landward changes in estuarine geometry influence tides and storm surges. Using measurements from the greater Charleston Harbor, SC, we find that constructing a dam either increases or decreases water levels, depending primarily on estuary convergence and surge event duration, as well as flow resistance and river flow. The presence of dams results in higher water levels, and thus flood exposure, when convergence is weak and storm surge at the sea has a short duration and high water levels. Further, channelization that extends inland, resulting from dredging of shipping channels, increases the magnitude and seaward extent of dam effects with increasing flood risk. Key Points: Estuarine geomorphic funneling and dams produce partial and full reflections, respectively, with magnitudes that are frequency dependentThree convergence regimes emerge: dominant tides have near peak amplification, overtides attenuate, and long duration surges mildly amplifyDams reflect and amplify long waves—increasing flood exposure—the most in weakly convergent estuaries with low friction [ABSTRACT FROM AUTHOR]

Coal mining in the Loess Plateau can very easily generate ground cracks, and these cracks can immediately result in ventilation trouble under the mine shaft, runoff disturbance, and vegetation destruction. Advanced UAV (Unmanned Aerial Vehicle) high-resolution mapping and DL (Deep Learning) are introduced as the key methods to quickly delineate coal mining ground surface cracks for disaster prevention. Firstly, the dataset named the Ground Cracks of Coal Mining Area Unmanned Aerial Vehicle (GCCMA-UAV) is built, with a ground resolution of 3 cm, which is suitable to make a 1:500 thematic map of the ground crack. This GCCMA-UAV dataset includes 6280 images of ground cracks, and the size of the imagery is 256 × 256 pixels. Secondly, the DRA-UNet model is built effectively for coal mining ground surface crack delineation. This DRA-UNet model is an improved UNet DL model, which mainly includes the DAM (Dual Dttention Dechanism) module, the RN (residual network) module, and the ASPP (Atrous Spatial Pyramid Pooling) module. The DRA-UNet model shows the highest recall rate of 77.29% when the DRA-UNet was compared with other similar DL models, such as DeepLabV3+, SegNet, PSPNet, and so on. DRA-UNet also has other relatively reliable indicators; the precision rate is 84.92% and the F1 score is 78.87%. Finally, DRA-UNet is applied to delineate cracks on a DOM (Digital Orthophoto Map) of 3 km2 in the mining workface area, with a ground resolution of 3 cm. There were 4903 cracks that were delineated from the DOM in the Huojitu Coal Mine Shaft. This DRA-UNet model effectively improves the efficiency of crack delineation. [ABSTRACT FROM AUTHOR]

The article describes the specific features and difficulties of monitoring the condition of an embankment dam with a clay-cement-concrete diaphragm. Moreover, it provides an overview and an evaluation of the applied monitoring methods. Additions to the existing set of measures for monitoring embankment dams with a clay-cement-concrete diaphragm are proposed. [ABSTRACT FROM AUTHOR]

The pathological role of interferon signaling is emerging in neuroinflammatory disorders, yet, the specific role of Interferon Regulatory Factor 3 (IRF3) in neuroinflammation remains poorly understood. Here, we show that global IRF3 deficiency delays TLR4-mediated signaling in microglia and attenuates the hallmark features of LPS-induced inflammation such as cytokine release, microglial reactivity, astrocyte activation, myeloid cell infiltration, and inflammasome activation. Moreover, expression of a constitutively active IRF3 (S388D/S390D: IRF3-2D) in microglia induces a transcriptional program reminiscent of the Activated Response Microglia and the expression of genes associated with Alzheimer's disease, notably apolipoprotein-e. Using bulk-RNAseq of IRF3-2D brain myeloid cells, we identified Z-DNA binding protein-1 (ZBP1) as a target of IRF3 that is relevant across various neuroinflammatory disorders. Lastly, we show IRF3 phosphorylation and IRF3-dependent ZBP1 induction in response to Aβ in primary microglia cultures. Together, our results identify IRF3 as an important regulator of LPS and Aβ -mediated neuroinflammatory responses and highlight IRF3 as a central regulator of disease-specific gene activation in different neuroinflammatory diseases. [ABSTRACT FROM AUTHOR]

The microbial biomass in soil is an active and living constituent of organic matter. It is both a storage pool and a source of plant nutrients that can be used as required. In addition, each microbial indicator evaluates soil quality and health from different perspectives, which are not necessarily very different. This study was conducted to compare some physical, chemical, and biochemical characteristics of the soils of forest (SF) and deforested (SDE) areas located on the slopes of the Kirazlıköprü area, which was previously deforested due to dam construction in Bartın province in northwestern Turkey. Soil samples were taken from the topsoil surface (0–5 cm) to determine the microbial soil characteristics of the SF and SDE sites. The soil microbial biomass N (Nmic) was determined by chloroform fumigation extraction, and the Cmic/Nmic ratio and Nmic/Ntotal percentage were calculated using the original values. Total N, Nmic and Cmic/Nmic values are higher in the forest area. The lowest and highest total N (Ntotal) contents in the SF and SDE soils varied between 1.50 and 3.47 g kg−1 and 0.91 and 1.46 g kg−1, respectively. Similarly, the Nmic contents of the SF and SDE soils varied between 75.56 and 143.42 μg g−1 and 10.40 and 75.96 μg g−1, respectively. A statistical analysis revealed that the mean Ntotal and mean Nmic values differed (p < 0.05) in the SF and SDE soils. The mean Cmic/Nmic values in the SF and SDE soils were 8.79 (±1.65) and 5.64 (±1.09), respectively, and a statistical difference was found between the fields (p < 0.05). Our findings indicate that the soil microbial community structure varies according to the site. As a result, it can be concluded that deforestation and erosion due to dam construction in the area led to the removal of plant nutrients from the soil; deterioration in the amount and activity of microbial biomass; and, consequently, soil losses and degradation of soil quality. [ABSTRACT FROM AUTHOR]

Environmental and ecological effects of the dam of the high-pressure Bratsk Hydroelectric Power Station (HPS) on the fish population and the probability of fish downstream migration from the Bratsk Reservoir have been studied. It has been revealed that thermal stratification of the water column is a significant factor in the ecological differentiation of the fish population in the upper reaches of high-pressure hydroelectric plants. According to hydroacoustics data, most of the ichthyomass, consisting of "warm-water" representatives of the Percidae (65%) and Cyprinidae (22%) families, is concentrated in the relatively warm layer of the epilimnion. Juvenile fish from 30 to 50 mm in size (up to 70% of the total fish number in this layer) are also concentrated here. In the cold-water hypolimnion, the fish population is represented by large single individuals of whitefish (Coregoninae). The data on distribution of fish in the lower and upper reaches of the dam, fish nutrition patterns, growth rate, and the presence of injuries that occur when fish pass downstream through hydroelectric plant dams are presented. Revealed differences in the growth rate of perches from the upper and lower reaches are associated with their constant inhabiting of water masses with contrasting temperatures. Net catches in the lower reaches over the four seasons of research lack injured individuals. These facts prove the absence of mass downstream passage of fish through the Bratsk HPS dam. Juveniles of cyprinids and perches accumulate in the upper warm layer of 0–10 m, i.e. outside the zone of the intake flow formation, which makes their entrance to intake openings at a depth of more than 20 m hardly possible. [ABSTRACT FROM AUTHOR]

Background and aims: Legal regulations for dispensing in Swiss heroin‐assisted treatment were relaxed during the COVID‐19 pandemic, allowing prolonged take‐home of up to 7 days instead of two to reduce patient contact and the risk of infection. Our study aimed to measure the consequences of this new practice. Design, setting and participants: This was a retrospective cohort study set in Switzerland's largest outpatient centre for opioid agonist therapy. One hundred and thirty‐four (72.4%) of the 185 patients receiving oral diacetylmorphine (DAM) participated in the study. Measurements: Through the utilization of electronic medication prescription and dispensing software, as well as the electronic medical record, the following data were extracted to explore the potential consequences: dose of DAM, the number of antibiotic therapies, emergency hospitalizations and incarcerations. Age, gender, prescriptions for psychotrophic drugs and additional prescription for injectable DAM were tested to assess an increased risk of losing prolonged take‐home privileges. Data in the year since prolonged take‐home (period 2) were compared with data from the equivalent prior year (period 1). Findings DAM take‐home was not associated with a change in DAM dose (P = 0.548), the number of emergency hospitalizations (P = 0.186) or the number of incarcerations (P = 0.215); 79.1% of all patients were able to maintain their extended take‐home privileges. However, patients who had injectable DAM experienced significant reductions in their prolonged take‐home privileges. Conclusion: Allowing patients to take home oral diacetylmorphine for up to 7 days as treatment for opioid use disorder does not appear to pose any demonstrable health risk. It is generally manageable for the large majority of patients. However, careful consideration of prolonged take‐home for patients with additional injectable diacetylmorphine is recommended, as these patients are more likely to lose take‐home privileges. [ABSTRACT FROM AUTHOR]

Background and aims: Legal regulations for dispensing in Swiss heroin-assisted treatment were relaxed during the COVID-19 pandemic, allowing prolonged take-home of up to 7 days instead of two to reduce patient contact and the risk of infection. Our study aimed to measure the consequences of this new practice. Design, setting and participants: This was a retrospective cohort study set in Switzerland's largest outpatient centre for opioid agonist therapy. One hundred and thirty-four (72.4%) of the 185 patients receiving oral diacetylmorphine (DAM) participated in the study. Measurements: Through the utilization of electronic medication prescription and dispensing software, as well as the electronic medical record, the following data were extracted to explore the potential consequences: dose of DAM, the number of antibiotic therapies, emergency hospitalizations and incarcerations. Age, gender, prescriptions for psychotrophic drugs and additional prescription for injectable DAM were tested to assess an increased risk of losing prolonged take-home privileges. Data in the year since prolonged take-home (period 2) were compared with data from the equivalent prior year (period 1). Findings: DAM take-home was not associated with a change in DAM dose (P = 0.548), the number of emergency hospitalizations (P = 0.186) or the number of incarcerations (P = 0.215); 79.1% of all patients were able to maintain their extended take-home privileges. However, patients who had injectable DAM experienced significant reductions in their prolonged take-home privileges. Conclusion: Allowing patients to take home oral diacetylmorphine for up to 7 days as treatment for opioid use disorder does not appear to pose any demonstrable health risk. It is generally manageable for the large majority of patients. However, careful consideration of prolonged take-home for patients with additional injectable diacetylmorphine is recommended, as these patients are more likely to lose take-home privileges. [ABSTRACT FROM AUTHOR]

Dams are one of the greatest threats to freshwater biodiversity and efforts to remove dams to restore riverine systems are increasing. However, dam‐removal studies have primarily focused on taxonomic responses to large dam removals with little work on the functional trait responses of fish to small‐dam removals; such a focus limits the application of results in regions with different taxonomic compositions.We explored taxonomic and functional trait responses of fish assemblages to two small‐dam removals over 10 years using a Multiple Before After Control Impact design at a dammed and an undammed river. Eight life‐history traits were used to calculate functional diversity (RaoQ) and determine the position of each fish species within a multivariate life‐history space relative to three life‐history strategy endpoints: opportunistic, periodic, and equilibrium. The distance of each species relative to these endpoints was used to calculate community weighted means (CWM), allowing us to examine the shift in life‐history strategy of a given assemblage after dam removal. Based on life‐history theory, we predicted a decrease in the CWM of equilibrium strategists and an increase in the CWM opportunistic strategists after dam removal.For the dammed river, we observed changes in assemblage structure at both the control and impact sites driven primarily by shifts from a lentic to lotic assemblage, with the most apparent change occurring in the formerly impounded sites. These changes tended to occur within 1 year, suggesting rapid colonization by lotic species after habitat change. By contrast, no change in assemblage structure was found for the undammed river, suggesting that dam removal was the primary driver of the shifts in assemblage structure observed in the dammed river. We found no change in the CWM of periodic strategists or RaoQ of all life‐history traits at any site after dam removal.Based on CWM, life‐history strategies shifted in response to dam removal at impounded sites where equilibrium strategists decreased and opportunistic strategists tended to increase after the impounded sites changed from a stable lentic environment to an unstable lotic environment, supporting predictions made by life‐history theory.Our results suggest that small‐dam removal may provide ecological benefits by restoring fish assemblages to a more natural riverine state and reversing the negative effects of dam construction on the ecosystem. We demonstrate that combining both trait‐based and taxonomic approaches can improve our ecological understanding of the impacts of dam removal on fish assemblages and provide relevant data for local management. [ABSTRACT FROM AUTHOR]

High Froude-number open-channel flows can entrain significant volumes of air, a phenomenon that occurs continuously in spillways, in free-falling jets and in hydraulic jumps, or as localized events, notably at the toe of hydraulic jumps or in plunging jets. Within these flows, turbulence generates millions of bubbles and droplets as well as highly distorted wavy air–water interfaces. This phenomenon is crucial from a design perspective, as it influences the behaviour of high-velocity flows, potentially impairing the safety of dam operations. This review examines recent scientific and engineering progress, highlighting foundational studies and emerging developments. Notable advances have been achieved in the past decades through improved sampling of flows and the development of physics-based models. Current challenges are also identified for instrumentation, numerical modelling and (up)scaling that hinder the formulation of fundamental theories, which are instrumental for improving predictive models, able to offer robust support for the design of large hydraulic structures at prototype scale. [ABSTRACT FROM AUTHOR]

This is the first study on the effects of the dam on channel morphology the downstream of dam on a global scale with a systematic review and meta-analysis approach. This study was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Therefore, the SCOPUS and Web of Science databases were searched using the Boolean operators 'AND' and 'OR' combined with keywords related to the subject area. All of the papers were in English and published up to 2023. Ultimately, 76 papers were evaluated for systematic review (qualitative analysis) and only 6 papers for meta-analysis (quantitative analysis). Results showed that the number of published papers has increased over time. In terms of channel adjustment, channel width decreased in the post-dam period, with narrowing and incision dominating in the downstream reaches. Meta-analysis showed that the dam has a moderately negative effect on channel width. Understanding these changes on a global scale can increase awareness of the impacts of dams on channel adjustment and their consequences. [ABSTRACT FROM AUTHOR]

Building Information Modelling (BIM) has emerged as a transformative force in the construction industry, gaining traction within the hydropower sector. This study critically examines the adoption and application of BIM throughout the entire lifecycle of hydropower projects, addressing a notable gap in existing research, to encompass a holistic approach to the management and resilience of these critical infrastructures. The objective is to delineate the comprehensive range of BIM applications, use cases, and adoption, integrating technologies including Digital Twin, UAV, GIS, and simulation tools, across components of hydropower projects. Employing a systematic search paired with a critical review of the selected literature, this study meticulously evaluates significant contributions in this domain. Through thematic analysis, the multifaceted utility of BIM in hydropower structures, including an in-depth evaluation of its current adoption within the industry, is presented. This encompasses an analysis of both benefits and challenges inherent in BIM implementation for hydropower infrastructures. This study is a significant contribution to understanding how BIM can be leveraged to enhance the resilience of hydropower infrastructures. It provides a comprehensive view of BIM's applications, challenges, and future potential, guiding stakeholders in adopting strategies that ensure these structures withstand, adapt, and recover from disruptions while maintaining sustainable and efficient operations. [ABSTRACT FROM AUTHOR]

The purpose of this study is to propose an impact analysis model to explore the effect of the post-earthquake landslide surge on local damage to ultra-high arch dams. Based on the existing pressure model of landslide-generated waves impacting the dam, nonlinear dynamic analysis is conducted on a high arch dam subjected to the landslide surge of different surge heights after the earthquake, through numerical simulation. According to the theory of nonlinear least squares, the relationship between the surge height and the damage value of all dam elements is fitted with a Sigmoid function, and the results show good fitting performance. This result proves that the proposed impact analysis model can well reflect the influence of the surge height on the local damage to arch dams. In addition, three parameters are defined based on this model. The influence of the post-earthquake landslide surge on the local damage of arch dams at different positions is analyzed based on these three parameters, and the vulnerable positions of the dam body under the impact of the post-earthquake landslide surge are determined. The model has important significance for the safety evaluation of dams affected by landslide-generated waves after an earthquake. [ABSTRACT FROM AUTHOR]

The stress-strain state and strength of the cutoff wall in the base layer of a tailings dam is assessed through numerical simulation [ABSTRACT FROM AUTHOR]

Dams play a vital role as a primary water supply for irrigation in Jordan, necessitating an assessment of their water quality. This study aimed to evaluate the suitability of irrigation water in a key number of Jordanian dams, namely Al Kafrain, Al Waala, King Talal (KTD), Mujib, Shuaib, and Sharhabil. Monthly readings of major water parameters (EC, Cl−, SO42−, HCO3−, Na+, Ca2+, and Mg2+) were recorded for seven years (2015–2021) for each dam. The assessment criteria included the sodium adsorption ratio (SAR), soluble sodium percentage (SSP), residual sodium carbonate (RSC), magnesium adsorption ratio (MAR), kelley ratio (KR), total hardness (TH), and water quality index (WQI) using both average (APL) and maximum permissible limits (MPL). Additionally, USSL, Wilcox, Doneen, Piper, and Gibbs diagrams were applied. The findings indicate that all the dams demonstrated suitability for irrigation based on the SAR, SSP, RSC, MAR, and KR values. The USSL diagrams showed most samples falling under C2S1 and C3S1, except KTD, which fell under C3S2. According to the Wilcox diagram, the water was either Excellent to Good or Good to Permissible, while the KTD water was classified as Permissible to Doubtful. Furthermore, the water chemistry was found to be mainly influenced by rock weathering, as revealed in the Gibbs diagram, and has no restriction on permeability, according to the Doneen diagram. The WQI showed that all the dams fall in the Good and Excellent category for irrigation using APL, while applying MPL, all the dams were in the Excellent category, which demonstrates the necessity of considering extreme events and regulatory thresholds. [ABSTRACT FROM AUTHOR]

This paper addresses the problem of removing 3D effects as one of the most challenging problems related to 2D electrical resistivity tomography (ERT) monitoring of embankment structures. When processing 2D ERT monitoring data measured along linear profiles, it is fundamental to estimate and correct the distortions introduced by the non-uniform 3D geometry of the embankment. Here, I adopt an iterative 3D correction plus 2D inversion procedure to correct the 3D effects and I test the validity of the proposed algorithm using both synthetic and real data. The modelled embankment is inspired by a critical section of the Parma River levee in Colorno (PR), Italy, where a permanent ERT monitoring system has been in operation since November 2018. For each model of the embankment, reference synthetic data were produced in Res2dmod and Res3dmod for the corresponding 2D and 3D models. Using the reference synthetic data, reference 3D effects were calculated to be compared with 3D effects estimated by the proposed algorithm at each iteration. The results of the synthetic tests showed that even in the absence of a priori information, the proposed algorithm for correcting 3D effects converges rapidly to ideal corrections. Having validated the proposed algorithm through synthetic tests, the method was applied to the ERT monitoring data in the study site to remove 3D effects. Two real datasets from the study site, taken after dry and rainy periods, are discussed here. The results showed that 3D effects cause about ±50% changes in the inverted resistivity images for both periods. This is a critical artifact considering that the final objective of ERT monitoring data for such studies is to produce water content maps to be integrated in alarm systems for hydrogeological risk mitigation. The proposed algorithm to remove 3D effects is thus a rapid and validated solution to satisfy near-real-time data processing and to produce reliable results. [ABSTRACT FROM AUTHOR]

Dam health monitoring is an important method for quantitative evaluation of dam safety. After long-term operation, there have missing data in dam monitoring data series inevitably due to the sensor damage or monitoring system failure problem which seriously affects the correctness of dam safety evaluation. The imputation accuracy of missing value is affected by data decomposition, reconstruction, and prediction methods. Therefore, in view of the high-precision imputation model of missing data in dam health monitoring, this paper proposes a data-driven fusion imputation model based on novel mode decomposition and deep learning method. First, the fusion imputation model is constructed based on extreme-point symmetric mode decomposition (ESMD), permutation entropy (PE), and bidirectional gate recurrent unit neural network (BiGRU). The ESMD-PE data preprocessing module can decompose the original data into a series of stable subsequences which can be input into the advanced deep learning BiGRU model to improve the interpolation accuracy. Then, the types of dam missing data and interpolation steps are studied. The engineering example illustrates that the root mean square error of the proposed model is decreased by 55.32% on average compared with four classical imputation models. The ESMD-PE–BiGRU fusion model can effectively simulate the inherent law of dam monitoring data and predict the missing data, which provides complete monitoring data for dam safety analysis. [ABSTRACT FROM AUTHOR]

Fish stranding in rivers, due to rapid shoreline dewatering, often occurs during the down‐ramping phase of hydropeaks, which enables peak energy production. Multiple hydropeaking characteristics and river morphology influence stranding, but little is known about the effects of riverbed microstructures. Our goal was to identify how the combination of hydropeaking characteristics and the occurrence of morphological microstructures (e.g., puddles and scour pools) influences fish stranding. For this purpose, we used an extensive dataset of fish stranding observations collected over 3 years in spring at 48 sites along a 50 km‐long reach of the Ain River, France. We aimed (1) to characterize stranding events and their associated fish assemblages and (2) to identify the spatial and temporal determinants of stranding. The occurrence of morphological microstructures was the main factor explaining fish stranding. Scour pools had a strong impact, followed by scour puddles, humid zones, and alluvial puddles. Then, hydropeaking characteristics interacted with morphology and modulated the intensity of stranding. Low flow ranges (low peak flow and low base flow) occurring after periods without hydropeaks induced 'salmonid fry' stranding events and 'super‐stranding' events (massive stranding of many taxa). Other flow ranges induced 'regular cyprinid fry' stranding events. Salmonids were particularly subject to stranding at the beginning of the sampling period. Recommendations are (1) to act in priority on sites where stranding is most likely, by morphological operations or by installing attractive structures in the perennial area and (2) to maintain attractive, perennial habitats in the low flow range of hydropeaks, for example, by increasing base flow. [ABSTRACT FROM AUTHOR]

The catastrophic failure of two dams in Libya on 10 and 11 September 2023 resulted in the devastating flooding of the city of Derna, which is located downstream of the dams, causing more than 6000 fatalities and displacing thousands of residents. The failure was attributed to heavy rainfall from Storm Daniel, leading to the dams reaching full capacity and subsequently overflowing and failing. This paper presents an analysis of the dam break, including the modelling of flow discharge and the resulting flooding of Derna. For validation purposes, this study compares the modelled quantities with post-event satellite imagery from UNOSAT and Copernicus, local reports, and data collected from social media using AI detection. The findings provide valuable insights into the dynamics of the dam break and its initial parameters, as well as an assessment of the accuracy of the results. The analysis is performed using a rapid estimation technique developed by JRC to provide the international emergency community with a swift overview of the impact and damage assessment of potential or actual dam break events. The use of all available data shows a satisfactory comparison with the calculated quantities. The rapid modelling of dam break events and combined analysis of multiple data types are proven suitable for promptly assessing the expected dynamic of the event, as well as reconstructing the unknown initial conditions before the break. Incorporating sensitivity analyses provides an estimate of the uncertainties associated with the deduced values of the unknown parameters and their relative importance in the analysis. [ABSTRACT FROM AUTHOR]

The complex aquatic system of dam reservoirs is known to trap emerging pollutants as microplastics (MPs) in sediments and water column. Considering the knowledge gaps in this type of environment, we investigated the amount and distribution of MPs in the surface water layer, as well as in the surface and deep sediments of the Siriu Reservoir in the Buzău River system, which is located in the southern area of the Eastern Carpathians, Romania. There was a discrepancy between MP abundancy in both water and sediment samples collected near the reservoir (5.3 MPs/m3, 315.5 MPs/kg) and at several kilometers downstream of the dam (1.4 MPs/m3, 132.5 MPs/kg). The chronological accumulation of MPs in the lacustrine sediments was determined by analyzing 5 cm intervals of a 50 cm length core extracted from the reservoir bed. By comparing the concentration of MPs identified in each interval with the solid debit volumes registered in the last decade, we found that flood events could be traced easily due to abundant MP accumulation. Morphologically, the particles were observed mainly as fibers and fragments. Fourier transform infrared spectroscopy (FT-iR) investigations identified most of the MPs as polypropylene (28%), polyethylene (26%), and polyethylene terephthalate (19%). [ABSTRACT FROM AUTHOR]

The wadis are environments of great ecological and economic importance. They are the seat of several hydraulic developments. The latter disrupts the functioning of the wadi in different ways. They modify their hydrological regime, disrupt the ecological conditions upstream and downstream of the reservoir, reduce the self-purification capacities, and modify the processes of erosion and solid transport. It is in this perspective that we have carried out a study of the impact of hydraulic installations on the quality of the waters of the Mafragh watershed. The hydrographic network of the watershed receives the wastewater discharged by the localities and by the industries located along these rivers. This wastewater contributes to the degradation of the water quality of the wadis. The spatio-temporal variation of the water quality index showed a good quality at the level of the dams, while at the level of the sites, which are located downstream, the quality generally varies between bad and very bad during the study period. [ABSTRACT FROM AUTHOR]

Rock-Filled Concrete (RFC) is formed by pouring High-performance Self-Compacting Concrete (HSCC) into gaps between pre-placed rocks (that form a strong rock skeleton) in the formwork. An in-depth analysis of RFC's elastic modulus must focus on its static and elastic modulus behavior, strength characteristics, and sustainability aspects. Mesoscopic finite element modeling effectively incorporates pre-positioned rocks, Self-Compacting Concrete (SCC), and the Interfacial Transition Zone (ITZ) to correctly predict performance. RFC is a promising alternative to traditional construction methods, offering combined advantages for masonry and concrete techniques while reducing cement usage. Studies continue to examine the creep properties of reinforced fiber composites, with promising signs of their effectiveness in reducing hydration heat and concrete shrinkage. Subaquatic conservation agents enhance environmental stewardship in wet situations. The elastic modulus of rock-filled concrete increases logarithmically, mostly influenced by the rock-fill composition. It is crucial to study the shape, size, and rock-fill ratio of rocks in RFC that impact its stability, strength, and resistance to static and dynamic loads. Irregularly shaped rocks can enhance interlocking and mechanical properties, while a well-graded mix of sizes improves compaction and uniformity. Studying these properties enables engineers to optimize design and construction for durability and performance. [ABSTRACT FROM AUTHOR]

Periphyton is the dominant primary producer in mountain streams and sustains the higher trophic levels. While certain periphyton groups, particularly diatoms, have received extensive study, the comprehensive characterization of the entire community has been largely neglected. This study aims to investigate the temporal pattern of biofilm in mountain streams characterized by different water thermal regimes. A one-year quantitative campaign, involving monthly samplings, was conducted in five subalpine streams in Northern Italy's Orobic Alps to collect epilithic biofilm from a wide surface area. The total biomass was quantified and the periphyton was analyzed both for composition (diatoms, green algae, cyanobacteria, and red algae) and for pigments. Disturbance, water temperature, physico-chemical conditions, nutrients, substrate diversity, and light availability were assessed concurrently with biofilm samplings. Results show sharp biofilm variations over months. In all sites, the disturbance was the primary factor reducing biomass and pigment content. Annually, all sites experienced similar turnover in periphyton composition mainly associated with light and water temperature. Overall, the study indicates that frequent quantitative investigations of biofilm help understand intra-annual variations and identify key drivers. Such information is useful to understand the ecosystem processes and the food web dynamics. [ABSTRACT FROM AUTHOR]

In August 2019, the local council of Umm al-Fahem, Israel, cancelled a scheduled performance of the known Palestinian rapper Tamer Nafar, claiming that Nafar's artistic work did not meet with the town's accepted religious, moral, and social norms. Subsequently, residents of the town and the Association for Civil Rights in Israel, petitioned the Court against the local council's interference with Nafar's freedom of artistic expression. Significantly, Nafar was not among the petitioners. The Court concurred with the petitioners, determining that the local council had no authority to interfere with Nafar's artistic content, and if there was concern regarding detrimental effects on public peace or security, police security should be provided for the event. Despite this ruling from an Israeli court, Nafar refused to perform in Umm al-Fahm. Instead, he accepted an invitation for dialogue with the conservative non-liberal forces within Umm al-Fahm council, a dialogue that resulted in reconciliation. I argue that Nafar's decision, as a liberal subject to choose dialogue with non-liberal forces in Palestinian society embodies the conceptual foundations of post-secularism, which extend beyond the binary of liberal/non liberal divisions and binaries and pave the way for internal dialogue between religious and secular actors. It constructs a platform for liberal subjects in Palestinian society to be heard in the public Palestinian sphere, providing social and political alternatives to the violent authority of Israeli law. [ABSTRACT FROM AUTHOR]

In this study, the changes in groundwater temperature at the base of the future dam of the Rogun hydropower plant are studied, with the aim of assessing the filtration characteristics of the base rock and determining the filtration coefficient and concentrated filtration path. In addition, the equation for the filtration coefficient is derived, which is used to calculate the filtration coefficient and rate of the filtered turbulent water movement. [ABSTRACT FROM AUTHOR]

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The present study examined temporal variations in water and sediment discharges in the Red River basin from 1958 to 2021 resulting from climate change and anthropogenic factors, with projections extended to 2100. The 64-year observational period was divided into five distinct stages: 1958–1971 (Stage I: natural conditions); 1972–1988 (Stage II: onset of human activities); 1989–2010 (Stage III: post Hoa Binh dam construction); 2011–2016 (Stage IV: series of new dam constructions); and 2017–2021 (Stage V: combined effects of human activities and climate change). Attribution analysis revealed that human activities accounted for 62% and 92% of the dramatic declines in sediment loads in Stages III and IV, respectively. Projection results of fluvial sediment loads over an approximate 150-year timeframe (1958–2100) indicate an overriding impact from human activities. Climate change projections based on four scenarios (−5%, +5%, +10%, and +15% change per year) suggest associated decreases or increases in river flows. This study predicts that projected 21st century increases in river flow attributable to climate change will offset up to eight percent of the human-induced sediment load deficit. [ABSTRACT FROM AUTHOR]

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The impacts of anthropogenic activities on surface water quality, heavy metals and microbial load of Awba Dam, University of Ibadan were studied for four months. Awba Dam was stratified into four stations (A, B, C and D) based on hydrological features. Two sampling points were randomly selected from each station. Monthly stratification covered September to December. Water samples were collected bi-weekly following standard procedures. Water samples collected were analysed for temperature (°C), dissolved oxygen (DO, mg/L); heavy metal (HM) (lead, iron, chromium and copper) in water (mg/L) and microbial loads (ML) (CFU/100 mL) according to standard methods. Data were analysed using descriptive statistics and ANOVA at α0.05. Significantly highest and least temperatures were 27.60 ± 2.23 and 27.10; DO (3.84 ± 0.35, 3.37 ± 0.11) in stations D and A, while BOD (5.81 ± 2.69, 5.30 ± 2.42) were recorded in stations A and B respectively. Significantly highest and least levels of HM were: lead (0.89 ± 0.35, 0.14 ± 0.06); iron (0.48 ± 0.08, 0.19 ± 0.05); chromium (3.51 ± 0.01, 1.50 ± 0.01) and copper (0.01 ± 0.01, 0.01 ± 0.01) were recorded in September and November, but ML (4.76 x 10-6 and 4.00 x 10-6) were obtained as highest and lowest in December and September respectively. Results from this study showed that, Awba Dam is contaminated with lead, iron, chromium and copper and ML. It is recommended that adequate monitoring and pollution reduction strategies be implemented to improve the aquatic resources of the dam. [ABSTRACT FROM AUTHOR]

The physico-chemical profile of the freshwater reservoir (dam) in Anandpur, Saurashtra, Gujarat, where limnological research was carried out from June 2021 to May 2023, is described in this report. Temperature, transparency, pH, electrical conductivity, dissolved oxygen, biological oxygen demand, acidity, alkalinity, total hardness, calcium hardness, magnesium hardness, chlorides, salinity, and other variables were examined in the surface water of the dam. These components' seasonal fluctuations were examined, and their interrelationships are addressed. Water had an alkaline pH. Summertime saw a rise in EC, whereas the post-monsoon season saw a reduction. Alkalinity and total hardness tended to drop in the winter and summer and to rise during and after the monsoon. The amount of dissolved oxygen was highest in the winter and lowest in the summer. Temperature and EC indicated an inverse connection with dissolved oxygen. Total 36 species of zooplankton were also recorded. The highest arthropodan and rotifer zooplankton species were recorded. [ABSTRACT FROM AUTHOR]

Context: Polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) are two families of persistent organic pollutants that are dangerous as they remain in the atmosphere for long periods and are toxic for humans and animals. They are found all over the world, including the penguins of Antarctica. One of the mechanisms that explains the toxicity of these compounds is related to oxidative stress. The main idea of this theoretical research is to use conceptual density functional theory as a theory of chemical reactivity to analyze the oxidative stress that PCBs and PBDEs can produce. The electron transfer properties as well as the interaction with DNA nitrogenous bases of nine PCBs and ten PBDEs found in Antarctic penguins are investigated. From this study, it can be concluded that compounds with more chlorine or bromine atoms are more oxidizing and produce more oxidative stress. These molecules also interact directly with the nitrogenous bases of DNA, forming hydrogen bonds, and this may be an explanation for the toxicity. Since quinone-type metabolites of PCBs and PBDEs can cause neurotoxicity, examples of quinones are also investigated. Condensed Fukui functions are included to analyze local reactivity. These results are important as the reactivity of these compounds helps to explain the toxicity of PCBs and PBDEs. Methods: All DFT computations were performed using Gaussian16 at M06-2x/6–311 + g(2d,p) level of theory without symmetry constraints. Electro-donating (ω-) and electro-accepting (ω +) powers were used as global response functions and condensed Fukui functions as local parameters of reactivity. [ABSTRACT FROM AUTHOR]

The management of water resources is a complex issue, and the conservation of fish and fishery resources is a growing challenge given the increase in the number of hydroelectric projects in Brazilian river basins. This study describes the fragmentation of the Tocantins–Araguaia River Basin resulting from the installation of hydroelectric plants in operation and planned by the electricity sector until 2050, as well as its relationship with the conservation of fish fauna, especially long-distance migratory species. The hydroelectric projects in operation and planned were analyzed using data obtained from the National Electric Energy Agency. A literature review was carried out to assess the fish species of the Tocantins–Araguaia ecoregion, with an emphasis on long-distance migrants. In general, 75 hydroelectric dams are in operation, and a further 119 projects are in the electricity sector's plans for construction by 2050 in the Tocantins–Araguaia ecoregion, including a stretch of the basin above the Tucurui dam, which will accentuate the fragmentation in the area. Of the 702 species found in the region, 31.1% are endemic, 6.1% are endangered, and several long-distance migratory species have had their populations restricted. Analysis of this information highlights the widespread impact on the ichthyofauna, affecting both species with a restricted distribution and migratory species with a long-distance distribution. The studies associated with the projects contribute to the advancement of knowledge, but they are only carried out after the works have been defined, which makes it difficult to plan conservation in advance. Transformations in the basin are imminent given the current changes and those expected in the coming years because of the electricity sector's planning for the region. Considering the inseparable relationship between biodiversity and socio-environmental and cultural diversity, fish conservation is intrinsically linked to the conservation of socio-diversity and the effective participation of local communities from the start of the process. Fish depend on water, and people need both water and aquatic diversity. In conclusion, a well-structured and adaptative conservation plan, combined with the integration of effective fish routes, can contribute to the sustainable development of hydroelectric projects while safeguarding the biodiversity and ecological integrity of the Tocantins–Araguaia Basin. [ABSTRACT FROM AUTHOR]

In November 2015, the Fundão Dam break released millions of tons of metal-rich tailings into the Doce River Basin (DRB), causing catastrophic damage and potential ecological effects that reached the Atlantic Ocean. This study aimed to evaluate the geochemistry and toxicity of water and sediments collected in the DRB from 2015 to 2019 and to determine the spatial and temporal trends. Water and sediment samples were analyzed for metals and As by inductively coupled plasma optical emission spectrometry (ICP-OES), and acute toxicity for Daphnia similis or D. magna. Results were explored using geochemical indices and correlation analyzes. Overall, higher concentrations of metals and As in water and sediments were observed immediately after dam breakage, but the levels exhibited a decreasing trend over time, although the levels of some elements such as As and Mn remained high in the upper DRB. The geochemical indices indicated mostly low to moderate contamination, and the enrichment factor (EF) demonstrated a higher enrichment of Mn in the upper DRB. Acute toxicity to water fleas (D. similis and D. magna) was occasionally observed in waters and sediments, but the reference samples were toxic, and the short-term effects were not correlated with metals and As. Overall, the results showed limited bioavailability of metals and As and a decreasing trend in their concentrations, indicating an ongoing recovery process in DRB. These results are important to decision-making regarding the disaster and actions for environmental restoration. [ABSTRACT FROM AUTHOR]

An important aspect of economic considerations is the routing and safety of hydraulic storage facilities such as dams for extreme probable water flooding. The routing of dam reservoirs requires more attention for determining the magnitude of extreme probable flooding. Apparently, the type of structure, importance, and economic development of the surrounding area guide the routing criteria for choosing the extreme flood magnitude. The Maithan and Panchet Dams in India have faced several major floods with diversified magnitudes since 1978. The present study aims to estimate the storage and routing of extreme probable floodings for these two dams based on real-time flood data like inflow, outflow, and elevation for the extreme flood years of 1978, 2009, and 2014. Reservoir storages at different elevations are calculated from the initial storage volumes. For both reservoirs, discharge equations are derived and calculated at given elevations during extreme floods. The Modified Puls technique is used for routing extreme floods. At the end of each extreme flood in 1978, 2009, and 2014, the variation in outflow discharges at different elevations and flood hydrographs is predicted. Finally, estimated outflow discharges are compared with the actual outflow discharges for the given inflows during extreme floods. Using this approach, extreme floods that occurred in 1978 are predicted with less than 10% error. Outcomes from this study may help in the future planning and routing of flood-control detention facilities and in predicting the variation in outflow discharges at different elevations. Based on this work, alternative studies and regional drainage planning can also be carried out. [ABSTRACT FROM AUTHOR]

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Dam operation and maintenance activities are critical, so the dam usually works and provides benefits according to plan. Over time, the performance of the Cacaban Dam has decreased significantly. The physical condition of the main building, supporting buildings, and instruments have experienced damage, which could pose a risk to the dam's safety. The main objective of this research is to determine priority strategies for improving operations and maintenance of the Cacaban Dam. Determining priority strategies for improving operations and maintenance in this research uses the DSS (Decision Support System) method with SWOT (Strength, Weakness, Opportunity, and Threat) and QSPM (Quantitative techniques Strategic Planning Matrix). Based on the SWOT analysis results, the resulting strategy is the Diversity Strategy, meaning that the Cacaban Dam is in good internal condition. In contrast, the external condition is not good. The proposed strategy is to minimize external threats/threats with strategic priorities referring to the scoring results using the QSPM method. Meanwhile, from the results of the dam performance assessment, Cacaban Dam obtained an average performance score of 3.45, considered adequate performance. However, if you look at several items of poor performance, there are two items, namely reservoir condition and border and greenbelt conditions, which have poor performance. There are seven components, namely intake buildings, spillway buildings, support hills, dam services, emergency action plans, instrumentation, and surrounding communities, whose performance is quite close to the deficient limit and has the potential for performance to decline. Extra handling is needed to restore the performance of dams and reservoirs. [ABSTRACT FROM AUTHOR]

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During the construction of the tailings dump of Udokan Mining and Metallurgical Works, filtration appeared at the base of the western dam. To increase the filtration density of the dam, a diaphragm wall made of bored-secant piles was constructed in the ground. Developing a composition of clay-cement concrete for the wall in the ground requires a significant amount of manufacturing and testing of samples. [ABSTRACT FROM AUTHOR]

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Slant range geometry plays a crucial role in interpreting synthetic aperture radar (SAR) observations, especially in converting line-of-sight (LOS) surface deformations to actual vertical subsidence. This paper proposes a new conversion model to retrieve vertical settlements of the embankment slopes using the geometrical parameters of the dam and the SAR sensor. The simulation results highlight the impact of slope foreshortening and heading direction of the satellite on deformation retrieval. Various SAR data with different resolutions and bands are used to analyze the model's performance, revealing a high conformity of the model with practical conversion parameters exceeding 80% for TerraSAR-X and Cosmo-SkyMed data. [ABSTRACT FROM AUTHOR]

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River ecosystems host a continuum of various discontinuities, such as dams and tributary inflows, which shape the habitats of aquatic organisms; this makes it important to evaluate the interactions among discontinuities and effects of a single discontinuity point. Herein, we focused on tributaries in dammed rivers to elucidate a manner to mediate discontinuities and hypothesized that the effects of the tributary inflow on the downstream river were mediated by the (1) distance between the dam and tributary inflow, (2) size ratio between the dam and tributary, and (3) ability of the tributary to transport fine sediments, such as sand and gravel. We conducted field investigations to measure 24 environmental factors, including the water column, riverbed, and river topography, along eight dammed rivers to test the three hypotheses. Only five factors differed significantly between the upstream and downstream sites of the tributary confluence, whereas 12 factors differed significantly between the tributary and mainstem. We also classified the variation pattern using principal component analysis (PCA). The correlation between each PCA axis and environmental factors suggests that the modifications of the water quality factors by tributary inflow were significantly correlated with the distance between the dam and the tributary inflow, and that the flux of various riverbed factors, that is, was significantly correlated with the ability to resupply of fine riverbed sediments by the tributary. Overall, tributary‐inflow downstream of a dam has the potential to be applicable in environmental restoration, especially in terms of resupplying fine sediment. [ABSTRACT FROM AUTHOR]

This research aims to evaluate the safety and performance of the Klego Dam in Boyolali, Central Java, using a quantitative descriptive method with primary and secondary data. The research stages involve damage analysis, adjustment of the dam's physical conditions to the research location, and analysis of the current conditions. Maintenance handling is prioritised using the Analytical Hierarchy Process (AHP) method, focusing on spillway channels, turbulent flow, and serrated sections. The physical conditions are analysed to determine the dam's status in 2022. The AHP program prioritises based on performance, safety, cost, damage, and component function. The results of the prioritisation scale for maintenance handling of the Klego Dam are as follows: (1) completing dam instrumentation with a priority matrix value of 0.646; (2) dam infrastructure repair with a value of 0.223; (3) completing the dam's emergency system with a value of 0.132. [ABSTRACT FROM AUTHOR]

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Timely release of flow from upstream hydropower generation facilities on the Peace River can enhance potential ice-jam flooding near the drying Peace–Athabasca Delta (PAD), a Ramsar wetland of international importance and homeland to Indigenous Peoples. An important consideration in deciding whether and when to commence a release is the celerity of the breakup front as it advances along the Peace River. Relevant historical data for a key stretch of the river are analyzed to determine average celerities, which can vary by an order of magnitude from year to year. Seven breakup events are identified that might have been candidates for a release, and the predictability of associated celerities is explored in terms of antecedent hydroclimatic variables, including cumulative winter snowfall, snow water equivalent on 1 April, ice cover thickness, coldness of the winter, and freezeup level. It is shown that celerity can be predicted to within a factor of two or less, with the freezeup level giving the best results. Three of the seven "promising" events culminated in PAD floods and were associated with the three highest celerities. The empirical findings are shown to generally align with physical understanding of breakup driving and resisting factors. [ABSTRACT FROM AUTHOR]