Water Discharge Research Articles

A Fuzzy Ballast Water Risk Assessment Model in Maritime Transport

Recent years have witnessed a growing awareness of the critical role that maritime transport plays in global sustainability, given its significant environmental, economic, and social impacts. Central to this concern is the management of ballast water, which, if not properly treated, can lead to the introduction of invasive species, biodiversity loss, and substantial economic and health repercussions. Traditional risk assessment models often fail to capture the complex uncertainties inherent in environmental risks associated with ballast water. This study introduces an innovative fuzzy logic-based risk assessment model designed to enhance decision-making processes in maritime operations by accurately assessing and mitigating the environmental risks of ballast water discharge. The model, structured using three fuzzy systems, integrates human reasoning with mathematical precision, providing an effective tool for sustainable maritime practices. The integrated fuzzy system employs 18 variables as inputs and yields three outputs (ballasting, ballast exchange, and de-ballasting risk). To evaluate the performance of the developed system, various data sets are used and tested through the MATLAB Fuzzy Toolbox. By aligning maritime operations with sustainability principles, this research contributes to the preservation of marine ecosystems, supports the economic stability of marine-dependent industries, and safeguards public health, underscoring the interconnectivity of maritime transport management with overarching sustainability objectives.

Degradation of Methylene Blue by Pulsed Nanosecond Discharge in Water with Ar-O2 Gaseous Bubbles

Degradation of Methylene Blue by Pulsed Nanosecond Discharge in Water with Ar-O2 Gaseous Bubbles

Chemical oxygen demand and biochemical oxygen demand analysis of discharge waters from laundry industry: monitoring, temporal variability, and biodegradability

In Europe, chemical oxygen demand (COD) and biochemical oxygen demand (BOD5) are used as organic indicators for the analytical characterization of laundry water. However, the values of these indicators are derived from one-off analytical measurements at a defined frequency. In addition, there are few data on the temporal variability of COD and BOD5 parameters and on water biodegradability beyond 5 days. In this work, samples of physicochemical treated wastewater were collected for 1 year and their content in COD and BOD5 measured, with BOD monitored over 35 days. The results showed that, for the 24 samples studied, the average and standard deviation values were 835 ± 176 mg/L for COD and 445 ± 114 mg/L for BOD5, indicating a biodegradability index of 2.0 ± 0.4. The interpretation of the data also indicated that the concentrations were close to emission limit value, particularly for BOD5. BOD21 values were particularly high compared to the initial COD, indicating the biodegradability of water. Laundry effluents were also rich in substances very quickly biodegradable, which has been demonstrated by the values of the ratio between BOD7 and BOD5. However, a significant proportion of surfactants is not degraded, as shown by measurements of total organic carbon and anionic surfactant analysis. The results of this study could help the industrial partner involved in our project to guide its choice of the complementary method to better treat wastewater and to reduce its organic load.

Sustained oxidation of Tea-Fe(III)/H2O2 simultaneously achieves sludge reduction and carbamazepine removal: The crucial role of EPS regulation

Establishing an economic and sustained Fenton oxidation system to enhance sludge dewaterability and carbamazepine (CBZ) removal rate is a crucial path to simultaneously achieve sludge reduction and harmless. Leveraging the principles akin to "tea making", we harnessed tea waste to continually release tea polyphenols (TP), thus effectively maintaining high level of oxidation efficiency through the sustained Fenton reaction. The results illustrated that the incorporation of tea waste yielded more favorable outcomes in terms of water content reduction and CBZ removal compared to direct TP addition within the Fe(III)/hydrogen peroxide (H2O2) system. Concomitantly, this process mainly generated hydroxyl radical (•OH) via three oxidation pathways, effectively altering the properties of extracellular polymeric substances (EPS) and promoting the degradation of CBZ from the sludge mixture. The interval addition of Fe(III) and H2O2 heightened extracellular oxidation efficacy, promoting the desorption and removal of CBZ. The degradation of EPS prompted the transformation of bound water to free water, while the formation of larger channels drove the discharge of water. This work achieved the concept of treating waste with waste through using tea waste to treat sludge, meanwhile, can provide ideas for subsequent sludge harmless disposal.

Deep learning of estuary salinity dynamics is physically accurate at a fraction of hydrodynamic model computational cost

AbstractSalinity dynamics in the Delaware Bay estuary are a critical water quality concern as elevated salinity can damage infrastructure and threaten drinking water supplies. Current state‐of‐the‐art modeling approaches use hydrodynamic models, which can produce accurate results but are limited by significant computational costs. We developed a machine learning (ML) model to predict the 250 mg L−1 Cl− isochlor, also known as the “salt front,” using daily river discharge, meteorological drivers, and tidal water level data. We use the ML model to predict the location of the salt front, measured in river miles (RM) along the Delaware River, during the period 2001–2020, and we compare predictions of the ML model to the hydrodynamic Coupled Ocean–Atmosphere‐Wave‐Sediment Transport (COAWST) model. The ML model predicts the location of the salt front with greater accuracy (root mean squared error [RMSE] = 2.52 RM) than the COAWST model does (RMSE = 5.36); however, the ML model struggles to predict extreme events. Furthermore, we use functional performance and expected gradients, tools from information theory and explainable artificial intelligence, to show that the ML model learns physically realistic relationships between the salt front location and drivers (particularly discharge and tidal water level). These results demonstrate how an ML modeling approach can provide predictive and functional accuracy at a significantly reduced computational cost compared to process‐based models. In addition, these results provide support for using ML models in operational forecasting, scenario testing, management decisions, hindcasting, and resulting opportunities to understand past behavior and develop hypotheses.

Influence of type and particle size of superabsorbent polymer on early water distribution and internal curing zone properties of cement paste

The types of commercial superabsorbent polymer (SAP) mainly include ionic-SAP acrylic acid (AA) and nonionic-SAP acrylamide-acrylic acid copolymer (AM), which have different particle sizes due to the limited preparation methods. This study used 1H low-field NMR to clarify the influence of type and particle size of SAP on the water distribution of cement paste. Backscattering electrons and nanoindentation were used to quantitatively analyze the area, porosity, and micromechanical properties of internal curing zone. Finally, void system analysis, compressive strength, and autogenous shrinking were systematically studied. The results indicate that the water absorption and retention capacity of AM in cement paste increase with the increase of particle size, and the area of internal curing zone also increased. As the area of internal curing area increases, the autogenous shrinkage of cement paste significantly decreases. The internal curing effect reduces the unhydrated cement content and increases the high-density C–S–H content of internal curing zone, thereby improving the micromechanical properties and to some extent offsetting the decrease in mechanical properties caused by voids. However, larger particle size AM forms larger void and higher air content, leading to a further decrease in strength. Ionic-SAP AA releases a large amount of water before final setting, weakening internal curing effect and reducing the area of internal curing zone. In addition, the early release of water leads to an increase in the local water-cement ratio, which increases the porosity and low-density C–S–H content of internal curing zone, thereby reducing the micromechanical properties.

A robust decision-making framework to improve reservoir water quality using optimized selective withdrawal strategies

In arid locations such as Oman, improving the quality of water released from a reservoir can be daunting. This is particularly true for Wadi Dayqah Dam, which struggles to provide sufficient, high-quality water for downstream needs. The study's objective was to establish more reliable operational guidelines, as well as identify vulnerable outlets and release ratios. To do so, a multi-objective optimization algorithm (NSGA-II) was combined with a selective withdrawal approach, using CE-QUAL-W2 and an Artificial Neural Network to simulate water quality in a reservoir. Then, a Robust Decision Making (RDM) approach was utilized to diagnose solutions that maintain acceptable water quality according to users’ requirements. Finally, scenario discovery models (Patient Rule Induction Method (PRIM) and Classification and Regression Tree (CART)) were used to calculate vulnerable outlets and release ratios based on the established threshold. The study adopted an XLRM framework to manage a proposed model under climate change scenarios and specify the effects of involved factors. XLRM stands for eXogenous factors, Levers used by the policy-makers, Relationships between L and X, and Measurement matrix to evaluate scenarios. This study found that a higher-quality reservoir release correlated with more activated outlets and decreased pollutant concentration. Evaluating robust solutions showed that vulnerability increased under scenarios with lower annual rainfall, and water released from low and mid-level outlets was more vulnerable than that from the surface. To enhance operational stability and reduce vulnerability, the suggestions advocate for a strategic approach in releasing varying water ratios from outlets situated at different levels. Specifically, the proposal emphasizes the controlled release of both smaller and larger volumes of water from outlets positioned at lower and higher levels within the dam structure, respectively. This deliberate variation in water release aims to bolster the overall resilience of the operational framework, contributing to a more robust and reliable system.

Dewatering and stress characteristics of stacking geotextile tubes under dry and underwater conditions

By filling and stacking geotextile tubes, cofferdams can be constructed with high efficiency and relatively low economic costs. However, the cofferdam construction at river estuary area may face significant challenges due to the limited time period of tide ebbing (e.g., 4 ∼ 6 h at Qiantang river estuary, Zhejiang, China) and the complexity of construction conditions (e.g., filling and stacking under dry and underwater conditions). First, tensile tests were carried out on the geotextile to obtain the tensile strength and stiffness of the material along the warp and weft, respectively. Subsequently, self-weight and stacking dewatering tests were conducted in a model container under both dry and underwater conditions. During the test, the pore water pressure, the height and strain of geotextile tube, and the volume of water discharge were monitored. Model test data revealed that, using an 80% dewatering degree as the formation criterion, the formation time of a geotextile tube is 4 ∼ 6 times longer for the underwater condition when compared to the dry condition. The earlier the stacking pressure was applied, the greater the final dewatering volume was achieved along with the reduced formation time. However, the early application of stacking pressure rendered higher risk of tensile failure of the geotextile.

Natural Polysaccharide-Based Hydrogels Used for Dye Removal.

Removal of contaminants from discharge water is vital and demands urgent assistance with the goal to keep clean water. Adsorption is one of the most common, efficient, and low-priced methods used in water treatment. Various polysaccharide-based gels have been used as efficient dye adsorbents from wastewater. This review summarizes cutting-edge research of the last decade of different hydrogels based on natural polysaccharides (chitin, chitosan, cellulose, starch, pullulan, and dextran) concerning their dye adsorption efficiency. Beyond their natural abundance, attributes of polysaccharides such as biocompatibility, biodegradability, and low cost make them not only efficient, but also environmentally sustainable candidates for water purification. The synthesis and dye removal performance together with the effect of diverse factors on gels retaining ability, kinetic, and isotherm models encountered in adsorption studies, are introduced. Thermodynamic parameters, sorbent recycling capacity along with conclusions and future prospects are also presented.

Scenario-based assessment of fecal pathogen sources affecting bathing water quality: novel treatment options to reduce norovirus and Campylobacter infection risks.

Wastewater discharge and runoff waters are significant sources of human and animal fecal microbes in surface waters. Human-derived fecal contamination of water is generally estimated to pose a greater risk to human health than animal fecal contamination, but animals may serve as reservoirs of zoonotic pathogens. In this study, quantitative microbial risk assessment (QMRA) tools were used to evaluate the hygienic impact of sewage effluents and runoff water from municipalities and animal farms on surface and bathing waters. The human-specific microbial source tracking (MST) marker HF183 was used to evaluate the dilution of fecal pathogens originating from the sewage effluent discharge to the downstream watershed. As novel risk management options, the efficiency of UV-LED disinfection and wetland treatment as well as biochar filtration was tested on-site for the contamination sources. According to the dilution pattern of the MST marker HF183, microbes from wastewater were diluted (2.3-3.7 log10) in the receiving waters. The scenario-based QMRA revealed, that the health risks posed by exposure to human-specific norovirus GII and zoonotic Campylobacter jejuni during the bathing events were evaluated. The risk for gastroenteritis was found to be elevated during wastewater contamination events, where especially norovirus GII infection risk increased (1-15 cases per day among 50 bathers) compared with the business as usual (BAU) situation (1 case per day). The noted C. jejuni infection risk was associated with animal farm contamination (1 case per day, versus 0.2-0.6 cases during BAU). Tertiary treatment of wastewater with wetland treatment and UV-LED disinfection effectively reduced the waterborne gastroenteritis risks associated with bathing. Based on the experiences from this study, a QMRA-based approach for health risk evaluations at bathing sites can be useful and is recommended for bathing site risk assessments in the future. In case of low pathogen numbers at the exposure sites, the MST marker HF183 could be used as a pathogen dilution coefficient for the watershed under evaluation. The full-scale implementation of novel tertiary treatment options at wastewater treatment plants (WWTPs) as well as on-site runoff water treatment options should be considered for infection risk management at locations where scenario-based QMRA implies elevated infection risks.

Shaded streams with permeable watersheds provide naturally resilient fish habitat refugia during heatwaves

AbstractStreamflow, dissolved oxygen, and water temperature underpin stream fish habitat suitability, so climate change could cause widespread habitat deterioration. Identifying stream characteristics that mediate habitat resilience to heatwaves will allow conservation effort prioritisation. Here, a set of readily applied metrics were used to assess hydrological and oxythermal responses of neighbouring salmonid streams, with distinctive geologies, soil‐types, and localised riparian shading, to periods of anomalously warm conditions. During heatwaves, low flows, warm‐water temperatures, and diel oxygen variability, associated with biogenic production and respiration, predominated. In a low‐shade stream lacking significant catchment water storage, high daytime (>22°C) and night‐time (>19°C) water temperatures and low early morning O2 concentrations (<5 mg L−1) accumulated oxythermal stress for salmonids throughout summer. A stream with localised shading and a higher proportion of underlying aquifers and permeable soils throughout its watershed experienced considerably less cumulative oxythermal stress (O2 > 6 mg L−1; temperatures <19°C), whilst slower release of subsurface water bolstered base flows during dry spells. Our findings support conservation of shaded streams with permeable watersheds characterised by higher soil infiltration rates and aquifer storage capacity as salmonid sanctuaries under a warmer, drier summer climate. Preventing water quality and hydromorphological deterioration are paramount for safeguarding their role as climate refugia.

Benefit of Multivariate Model Calibration for Different Climatic Regions

AbstractHydrological models are traditionally calibrated against observed discharge. However, for a given model, similar performance for discharge simulation can be achieved through a variety of parameter combinations, some of which produce unrealistic simulations of non‐discharge variables. Thus, considering non‐discharge variables in calibration can help to reduce equifinality and give more realistic simulations. Few studies considered non‐discharge variables in calibration and evaluation and across a large sample of catchments. In this study, we calibrate the lumped SIMHYD model with several combinations of different hydrological variables such as discharge, actual evapotranspiration, soil wetness, and total water storage. The various calibration scenarios are conducted across 550 catchments in Australia spanning arid, tropical and temperate regions. We show that the performance of the discharge‐calibrated model for actual evapotranspiration, soil wetness, and total water storage is strongly related to the co‐seasonality of discharge and the respective variable. Considering actual evapotranspiration, soil wetness, or total water storage in addition to discharge in calibration improves the simulation of the added variable on average by 53%, 58%, and 41%, respectively, which comes at the expense of decrease in discharge performance by 5%. Cross‐benefits, that is, the improved simulation of a variable by considering another variable in calibration, mainly occurs between actual evapotranspiration and total water storage and are most pronounced in humid catchments with highly seasonal soil wetness. We also find that when using all four variables in model calibration, the trade‐off in model performance between discharge and the other variables gets more pronounced with increasing catchment wetness.

Hydrological function of rewetted peatlands linked to saturated hydraulic conductivity in Kubu Raya, West Kalimantan, Indonesia

Hydrological function of rewetted peatlands linked to saturated hydraulic conductivity in Kubu Raya, West Kalimantan, Indonesia

Host density and anthropogenic stress are drivers of variability in dark spot disease in Siderastrea siderea across the Florida Reef Tract

Dark spot disease (DSD) was first reported within Florida's coral reefs in the 1990s but factors affecting its spatial distribution have not been well studied. We used a 14-yr (2005–2019) coral monitoring data set, utilizing 2242 surveys collected along Florida's coral reefs (about 530 linear km) to explore the spatial and temporal patterns of DSD occurrence. We built predictive statistical models to test for correlations between a suite of environmental and human impact factors and the occurrence of DSD in the reef coral, Siderastrea siderea. DSD in S. siderea is a chronic disease which occurred in all 14 yrs of the study. Annual DSD prevalence ranged from 0.45% to 4.4% and the proportion of survey sites that had DSD ranged from 4.8% to 30.9%. During the study period, DSD became more widespread across Florida's coral reefs and affected a higher proportion of S. siderea populations. Spatial variations in DSD correlated with environmental and human factors which together explained 64.4% of the underlying variability. The most influential factors were concentration of silica in the surface waters (a proxy for freshwater input), the total number of coral hosts, and distance to septic areas. DSD occurred in all regions, but the highest cumulative prevalence occurred in the upper Keys on reefs around major urban centers with links to coastal water discharges. Our results support the hypothesis that coastal water quality is a key component of DSD disease dynamics in Florida and provides motivation for addressing land–sea connections to ameliorate disease occurrence in the region.

Tracking the Nearfield Evolution of an Initially Shallow, Neutrally Buoyant Plane Jet Over a Sloping Bottom Boundary

AbstractUnderstanding coastal plane jets which occur when a body of water discharges into an ocean or a lake through a channel or outlet is important, since they play a significant role in sediment, nutrient, and pollutant exchange. This study investigates the nearfield of initially shallow, neutrally buoyant plane jets, bounded by a free surface and a sloping bottom (Sloping Bottom Jet; SBJ) that issue into a laterally unconfined quiescent ambient both experimentally and numerically, and compares them with a plane jet flowing over a horizontal bottom (Horizontal Bottom Jet; HBJ). Results revealed that, different from the HBJ, the width and centerline velocity of SBJ decrease near the mouth. The SBJ width gradually increases after that as the transverse longitudinal velocity profile progressively transforms from a “top‐hat” into a Gaussian distribution. Once the Gaussian distribution is established, both jets diverge and centerline velocity decreases. Shear layers are generated on the sides of both jets with Kelvin Helmholtz‐type Coherent Structures (KHCS) developing inside. KHCS produce periodic velocity fluctuations with a Strouhal number of ∼0.079 and contribute significantly to momentum exchange and turbulent kinetic energy production. Since the thickness of the SBJ increases longitudinally, the vertical extent of KHCS also increases. When the two shear layers meet and merge at the centerline, they cause a flapping motion of the jet. This location is closer to the jet mouth for SBJs than for the HBJ. These findings demonstrate that a sloping bottom modifies the flow field from quasi‐2D for the HBJ to strongly 3D for SBJs.

Land Subsidence Phenomena in Joshimath Town, Garhwal Himalaya, India: Field Observations and Possible Causes

Astract The town of Joshimath, in the state of Uttarakhand, India, has been witnessing severe ground subsidence problems. Though the land subsidence has been documented since a long time, there were sudden enhanced appearance of cracks on the ground and in houses overnight on 2nd and 3rd of January 2023, in the western segment of the Joshimath town. At the same time, there was high-volume of sediment-laden water discharge inside the Jaypee Colony beginning from 3rd of January 2023. More than 1000 houses and infrastructure were severely damaged during this event. Therefore, it is being of high importance to study the present situation and highlight the possible reasons that make this area vulnerable to land subsidence. With this aim, the present study incorporates different data sources and field observations to provide an overview of the present situation of the Joshimath town.

Statistical analysis and water quality modeling towards holistic health assessment of Himalayan and peninsular rivers of India

Water occurs naturally in a variety of forms. Liquid water is present in rivers, lakes, the ground, the sea, and precipitation. The primary objective of water quality monitoring is to ascertain whether the water quality being observed is appropriate for its designated purposes. An investigation was undertaken to assess the concentration levels of various water quality parameters, including total hardness, electric conductivity, temperature, Ca, Cl, K, Mg, Na, SO4, and HCO3. The research assessed the physicochemical parameters of ten (10) rivers, including the following: Brahmaputra (Arunachal Pradesh); Barak (Assam); Godavari (Maharastra); Brahmani (Odisha); Sabarmati (Gujarat); Tapi (Gujarat); Mahi (Gujarat); and Ganga (Uttar Pradesh). Water samples were obtained from the aforementioned rivers spanning the years 2013 to 2020. Descriptive Analysis, one-way ANOVA, Covariance, and Correlation were utilized to examine the impact of the rate of change on the interrelationships among the parameters. At the current level, the Narmada River cannot meet the daily demands that arise during and after the monsoon. The primary sources of pollution were inputs from households, businesses, and agriculture. The Gang River portions have been poisoned by sewerages, untreated industrial discharges, and chemical surges from agricultural fields. The basin is still being impacted by a number of anthropogenic pressures associated with an expanding human population, such as changes in land use, elevated water pollution, increased water demand, river channelization, and the Brahmanputra River's regulating flow. Anthropogenic heavy metals Cu, Cd, Cr, Pb, and Ni have not been shown to exhibit seasonal changes; however, geogenic heavy metals Mn, Fe, Mg, and Ca have been recorded to undergo seasonal oscillations in the Barak River and Still. The alkaline impacts of the Godavari water sample on the river are shown by the physical-chemical analysis of the samples. The amount of dissolved oxygen has decreased at various sites when pollutants are added to the water. A rise in BOD and turbidity levels is a result of the introduction of contaminants at different sites. The tests of TDS and F-coli showed an increase in value because of the sewage and burial procedures. Reduced flows below the dam and sudden increases resulted in a significant loss of organisms due to water discharge for hydropower generation. The Krishna River lost several of its characteristic characteristics as a result of dams being built both upstream and downstream. The Brahmani River's summertime dissolved oxygen (DO) levels are found to vary from 6.16 to 7.81 mg/L. The Brahman River's water quality index varied from 36.7 to 44.1, which is considered excellent water quality. Huge public awareness, strong implementing environmental policy decisions are some of the potential solutions to increase the health conditions of the Himalayan and Peninsular rivers of India. India's Himalayan and Peninsular rivers' health is measured via water quality modeling. This study evaluates river health using physiochemical and biological parameters. This study examines Himalayan and Peninsular India's water resource management, environmental preservation, and public health.

Sodium Alginate Chitosan Crosslinked Hydrogel Amoxycillin Absorption Properties

ABSTRACT Wound healing refers to the replacement of destroyed or damaged tissue of a living organism by newly produced tissue, and the time taken is known as wound regeneration time. Wound care is a major challenging biomedical field due to the delayed healing process or delayed wound regeneration time. The factors responsible for delayed wound healing are poor oxygen flow, less exposure to moisture, diseases such as diabetes and cancer, etc., Wound dressings that are formulated from biopolymers such as chitosan, chitin, and cellulose have properties such as biocompatibility (compatible with living systems and does not cause any immunological rejection), biodegradable, nontoxic with minimal side effects, anti-microbial, anti-inflammatory properties. Chitosan is obtained from scales of fish and shrimp. It contains highly reactive amine groups and sodium alginate, which is a polysaccharide produced from seaweed and bacteria and is biocompatible with living systems and biodegradable polysaccharides. This study is based on the development of sodium alginate crosslinked hydrogel and testing the properties of hydrogel with amoxycillin drug and water release property of the drug.

Adaptation of Fildes Peninsula Lakes (King George Island, East Antarctica) to climate change and anthropogenic impacts

The load on the Antarctic oases has been recently increasing, with intensive research carried out by various countries and ecological tourism developing. This leads to an increase in the impact on the aquatic ecosystems of the lakes and streams in addition to the warming climate and glacier melting. This paper presents findings from a study of the Fildes Peninsula (King George Island) lakes’ aquatic ecosystems in the summer period of January–February 2020. In addition to results of hydrological and hydrochemical studies, the paper provides data from measurements of the self-cleaning ability of representative oasis lakes, as well as greenhouse gas fluxes from the lakes surface. The water level of the streams decreased 5 times over the summer season, and the water discharge — 10 times. The streams flowing from the glacier have the fullest water. The lakes have a neutral reaction, sometimes weakly alkaline; they are well aerated: the average value of dissolved oxygen in water is 85 %, occasionally supersaturation of up to 137% was observed. The concentration of nutrients in the water has amplitudes that are considerable for Antarctic oases lakes. A significant correlation can only be observed between nitrates and phosphates, and also between the water turbidity and the nutrients’ concentration. Maximum turbidity is observed in lakes with abundant content of bacterial mats. Most of the lakes have hydrochemical type II sodium chloride waters. The assessment of the lake self-cleaning ability using the ratio of destruction and organic matter production showed the general ability of ecosystems to cope with external (natural) pressures on ecosystems, but not in all cases. Eutrophication of the lakes and stream valleys is also noted. Carbon dioxide (CO2) absorption was observed in most of the streams and lakes, in some of them — methane (CH4) absorption as well. However, CH4 is generally emitted from the surface of the lakes. The largest values are recorded for small lakes located on glacial moraines and in places where ornithosoils are present. The agreement of the findings from the hydroecological studies of the Fildes peninsula lakes with those presented earlier by other authors makes it possible to conclude that there is a certain resistance of the lakes to climatic changes, but one can already talk about a significant anthropogenic impact on the freshwater oasis ecosystems.

POTENSI PLTMH DI BENDUNGAN SIDAN, DESA BELOK SIDAN, KABUPATEN BADUNG

The potential of new renewable energy is highly needed to support Clean Energy Bali, and one of the viable energy sources is Micro Hydro Power Plant (PLTMH). The design of the Sidan Dam PLTMH is based on the construction of the Sidan Dam area in Belok Sidan Village, Badung Regency. The planning of the Sidan Dam PLTMH only extends to the construction of the penstock. In this Capstone Project, the design of the Sidan Dam PLTMH utilizes water discharge and head height data from the Sidan Dam planning. This data is used to determine the design, type of water turbine, dimensions of the water turbine, and to determine the appropriate generator capacity. The calculation results indicate that the Sidan Dam PLTMH has a potential capacity of 290.83 kW with a Francis turbine type and a generator capacity of 472.59 Kva. It is estimated to generate an annual energy output of 1,783,396 kWh with a capacity factor 70%.