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Stormwater is considered a pathway of microplastics to surface water systems, but the magnitude of microplastic pollution in stormwater and the efficacy of existing stormwater treatment methods are unknown. One potential solution for minimizing microplastics in surface waters is leveraging green infrastructure, such as green roofs, bioswales, and bioretention cells, which can be optimized for the removal of conventional and emerging contaminants. The goals of this study were to (1) establish baseline types and quantities of anthropogenic microparticles, including microplastics, found in stormwater, and (2) evaluate bioretention as a possible solution for reducing microplastics in stormwater. To understand baseline conditions, samples were taken from five different catch basins in north Portland, Oregon, during four storm events and analyzed to quantify and characterize microparticles between 106 μm and 5 mm. A baseline concentration of 4.5±2.2 (range 1.1–9.7) particles/L was found, with no observed differences in concentrations between sampling locations or storm events. Most identified microparticles were fibers (66%), and approximately 47% of the particles were cotton, followed by polyester/blend (33%) and nylon (9%). Microparticle concentrations were correlated with the concentration of total suspended solids and the number of pieces of litter collected during a litter survey. To determine the efficiency of bioretention systems for microplastic removal, laboratory bioretention columns were constructed and filled with three different geomedia (a City of Portland, Oregon, standard mix, a proprietary mix, and layered sand and compost). A total of nine columns (three replicates of each geomedia) were tested with stormwater collected from a catch basin in Portland that was spiked with synthetic microplastics (106–5,000 μm). A removal efficiency of 99.8% was observed across all bioretention columns, regardless of the media type. Results indicate green stormwater infrastructure, such as bioretention, may be an effective tool for reducing observed microplastic transport from urban runoff to receiving water bodies. [ABSTRACT FROM AUTHOR]

This study addresses a persistent environmental concern related to graywater discharge from households, highlighting its potential to contribute to increased pollution in water bodies. To mitigate this issue, the research explores the use of subsurface flow‐built wetlands, specifically focusing on the innovative application of constructed tidal and vertical flow wetlands (CTWFWs) as wastewater treatment systems. The study not only evaluates the efficacy of these CTWFW systems but also delves into the crucial aspects of their operation and their interactions with the biological, physical, and chemical characteristics of graywater. A key innovation of this research is the investigation of zeolite's effectiveness and the utilization of perlite‐based plant species in both mixed and monoculture configurations to develop lab‐scale hybrid constructed wetlands (HCWs). These HCWs are designed for the removal of organic matter and nutrients from graywater, offering a sustainable and cost‐effective solution to this environmental challenge. The study also examines the dynamic processes involved in graywater treatment, emphasizing how the removal of parameters like biological oxygen demand (BOD), nutrients, total suspended solids (TSS), and disinfection efficiency can significantly impact the effectiveness of treatment systems. Furthermore, the research scrutinizes the intricate relationship between the treatment unit's dimensions and the specific criteria that need to be met for efficient graywater treatment. Intriguingly, the study tracks the changes in graywater composition and the treatment process over time. By conducting on‐site measurements of various physicochemical characteristics such as temperature, dissolved oxygen (DO), electrical conductivity (EC), turbidity, total dissolved solids (TDS), and pH, the research offers a comprehensive understanding of the treatment system's performance and adaptability. The study dives into the microbial communities within the treatment systems, utilizing 16S rRNA amplicon sequencing to characterize the complex microbial ecosystem present in graywater. This approach sheds light on the interplay between microorganisms, physicochemical conditions, plant responses, substrate dynamics, and the production of microbial metabolites. It underscores the holistic nature of the research, encompassing various aspects of graywater treatment. Notably, the study explores the application of biochar in combination with the target heavy metal, cadmium (Cd), within constructed wetlands (CWs). This innovative approach aims to better understand the kinetics and isothermal adsorption of lead in the context of mouthwash residue, expanding the knowledge base in this critical area. The research findings are substantial, with remarkable removal efficiencies achieved for parameters like TSS, turbidity, chemical oxygen demand (COD), nitrate, and phosphate. These results underscore the practicality and effectiveness of the proposed treatment methods. This holistic and pioneering research significantly advances the understanding of sustainable graywater treatment, offering valuable insights and practical solutions to mitigate water pollution concerns. Practitioner Points: This study addresses a persistent environmental concern related to greywater discharge from households, highlighting its potential to contribute to increased pollution in water bodies.The study not only evaluates the efficacy of these CTWFW systems but also delves into the crucial aspects of their operation and their interactions with the biological, physical, and chemical characteristics of greywater.A key innovation of this research is the investigation of zeolite's effectiveness and the utilization of perlite‐based plant species in both mixed and monoculture configurations to develop lab‐scale hybrid constructed wetlands (HCWs). [ABSTRACT FROM AUTHOR]

The Ruki is a pristine blackwater tributary in the Congo Basin draining tropical lowland forest. Daily discharge and fortnightly concentrations, isotopic ratios, and molecular composition of carbon and organic matter were measured for 1 yr (2019–2020). Like the Congo River, discharge peaked from November–January, with a smaller secondary peak in June. Dissolved organic carbon (DOC), inorganic carbon (DIC), carbon dioxide (pCO2), and methane (pCH4) concentrations were high (21.3 ± 4.8 mg C L−1, 5.8 ± 0.9 mg C L−1, 6370 ± 1740 ppm, and 250 ± 100 ppm, respectively) and positively correlated with discharge, indicating transport limitation. Total suspended solids and particulate organic carbon (POC) concentrations were generally low (3.68 ± 1.61 mg L−1, 0.88 ± 0.33 mg C L−1, respectively) and varied inversely with discharge, indicating source limitation. The Ruki exported a total of 3.25 Tg C yr−1, of which DOC, DIC, and POC comprised 76%, 20%, and 3%, respectively. This DOC flux represents ~ 20% of the annual Congo Basin flux from about 5% of its area, highlighting the high yield. Isotopic ratios of DOC and POC indicate modern C3 forest vegetation as a source, except for a few older samples potentially indicating peat inputs. The bulk molecular composition of dissolved organic matter was seasonally consistent; however, a more oxidized and aromatic assemblage occurred at high discharge, corresponding with forest vegetation, while a more aliphatic, nitrogen‐, and sulfur‐enriched assemblage was found during low discharge, corresponding with soil‐derived organic matter. Overall, these results underscore how hydrology controls C concentrations in the Ruki River and how this blackwater river contributes disproportionately to C export per unit area within the Congo Basin hydrosystem. [ABSTRACT FROM AUTHOR]

This study elaborates on the important role of nanofibers produced from polyacrylonitrile after reinforcement with iron nanoparticles (γ-Fe2O3), to expand the applications of these fibers and to combine their ability to remove Nickel (II) from aqueous solutions with their ability to remove pollutants such as total suspended solids, total nitrogen, chemical oxygen demand, and cyanide as well as killing the bacteria in wastewater. The results of the absorption of Nickel (II) after treatment of the aqueous solution were obtained by an atomic absorption spectrometer type (AAs-7000) and a spectrometer type (Hach DR2800) after treating samples of wastewater obtained pollutant absorption results. The adsorption kinetic parameters results for Nickle (II) proved that the rates of increase in the maximum absorption capacity were 43.27 to 133.5 and from 74.63 to 178.571 mg/g when increasing the initial concentration (10-50 mg/L) for first and second order models. The pH, contact time, electrical conductivity, and initial concentration are good indicators of adsorption efficiency of Nickel (II), the high removal efficiency was 23.96 % at low initial concentration. Also, an increase the reduction rate and increased in TN: TP ratio were significant to increase the reduction rate of the total bacteria up 90 % at 8 h. [ABSTRACT FROM AUTHOR]

The use of Internet of Things (IoT) in industries is not new; however, the amalgamation of IoT and Biotechnology is still less explored. IoT in wastewater treatment comes with a full suite including cloud and its corresponding ecosystem. The available cloud‐based systems are advantageous, but costly and tightly coupled to their own cloud infrastructure. Opportunities are limited for the creation of a hybrid/multiple cloud model as it's difficult to integrate with the legacy system(s) and/or customized systems. The current investigation focuses on designing architechture of an open source IoT platform on an effluent treatment plant (ETP) protoype of textile industry. The designed prototype includes physical (adsorption) and biological (Rotating Biological Contactor, RBC, immobilized with white rot fungus) processes. IoT has been used for automated data monitoring of pH and ultrasound (for effluent flow from one tank to another, with respect to the water level, for processing). The process operated under an optimized pH (6.53±0.15) with reduction of representative wastewater quality parameters, biological & chemical oxygen demand, total dissolved solids, total suspended solids and optical density by 78.9, 52.15, 91.6, 20.3 and 88.8%, respectively. The findings demonstrated the reliability of the designed system and the analytics on treatment facilities. [ABSTRACT FROM AUTHOR]

Millions of cubic meters of water are polluted every day as a result of industrialization and other human activities. The contribution of the Wastewater Treatment Plant, which was built to prevent this pollution, to the water cycle was examined through water footprint indicators in this study. In the study, the wastewater treatment plant was evaluated for treated and non-treated cases, and the contribution of the plant to the grey water footprint was determined from the difference between the two cases. Wastewater Treatment Plants not only save the volume of water in the receiving environment but also protect the water quality. This study revealed that as a result of the treatment of industrial and domestic mixed wastewater with a pollution load of 396.297 mg biochemical oxygen demand L-1, 924.245 mg chemical oxygen demand L-1, 26.139 mg total nitrogen L-1 2.76 mg total phosphorus L-1, and 426.861 mg total suspended solids L-1, in the Wastewater Treatment Plant, it recovered an average of 14,375,243 m3 of freshwater per month in the water cycle by protecting the Class III (medium) water quality of receiving environment. The calculations made in the study are based on the Water Footprint Assessment Manual. The volume of recovered water is 19 ± 14 times larger than the inlet flow of wastewater treatment. On the other hand, the total amount of freshwater consumed directly and indirectly in the wastewater treatment is 3696 m3 month-1. ⁓97.093% of the indirect blue water footprint is used for the generation of electrical energy. This study reveals all aspects of the Wastewater Treatment Plants contribution to the sustainable environment with the natural water cycle and the protection of the receiving water quality. [ABSTRACT FROM AUTHOR]

Remote sensing plays a crucial role in modeling surface water quality parameters (WQPs), which aids spatial and temporal variation assessment. However, existing models are often developed independently, leading to uncertainty regarding their applicability. This study focused on two primary objectives. First, it aimed to evaluate different models for chemical oxygen demand (COD), total phosphorus (TP), total nitrogen (TN), and total suspended solids (TSS) in a surface water body, the J. A. Alzate dam, in the Mexican highland region (R2 ≥ 0.78 and RMSE ≤ 16.1 mg/L). The models were estimated using multivariate regressions, with a focus on identifying dilution and dragging effects in inter-annual flow rate estimations, including runoff from precipitation and municipal discharges. Second, the study sought to analyze the potential scope of application for these models in other water bodies by comparing mean WQP values. Several models exhibited similarities, with minimal differences in mean values (ranging from −9.5 to 0.57 mg/L) for TSS, TN, and TP. These findings suggest that certain water bodies may be compatible enough to warrant the exploration of joint modeling in future research endeavors. By addressing these objectives, this research contributes to a better understanding of the suitability of remote sensing-based models for characterizing surface water quality, both within specific locations and across different water bodies. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the water quality in two streams of the Valles region of Jalisco, Mexico and fully determine if they are being used as tequila vinasse disposal sites. Three sampling campaigns were carried out at eight different points of the two streams that run near tequila factories (TFs). Different physicochemical parameters of water quality were measured: chemical oxygen demand (COD); biochemical oxygen demand (BOD5); total suspended solids (TSSs); total phosphates; fats, oils, and grease (FOG); Kjeldal nitrogen; nitrite; nitrate; pH; conductivity; temperature; dissolved oxygen (DO); and turbidity. Also, the analysis of samples of tequila vinasses (TVs) diluted with tap water were carried out to have a reference for the level of pollution in the streams. Furthermore, due to the fact that COD could be considered the main indicator of pollution with TVs, a linear regression was performed between COD concentrations and the percentage of dilution of TVs (with tap water). A positive correlation was found between these two variables, and based on this analysis, the vinasse content was estimated at each sampling point of the streams. It was found that on average, a volume of 8.5 ± 6.3% and 11.5 ± 4.9% of TVs were present in each sampling point of the Atizcoa and Jarritos Streams, respectively. Additionally, it was found that, in general, the concentration of pollutants increased as the streams passed through the TFs, particularly the Atizcoa Stream. According to the Water National Commission criteria, most of the points would be classified as highly polluted, since they reach concentrations of COD and BOD5 up to 6590 mg/L and 3775 mg/L, respectively, temperature values up to 37 °C, and DO values of 0.5 mg/L. Therefore, it was confirmed that the streams are being used as tequila vinasse disposal sites. Due to the above, there is an urgent need for tequila companies to implement treatment systems for the vinasse generated, since under current conditions, the monitored streams are practically devoid of aquatic life. [ABSTRACT FROM AUTHOR]

The use of a natural and low-impact way of managing surface water and groundwater in a sunken plaza is meaningful for urban ecological development. To achieve water storage, purification, and recycling, this study investigated a water circulation system in a sunken plaza based on the groundwater and surface water transformation and combination. A joint water-stop curtain system was constructed with underground continuous walls, RC wall, building main structure, adjacent support structure, and waterproof stratum at the bottom of the main structure. On the basis of the stratum data and parameters of the study area, a three-dimensional (3D) groundwater model was built using FEFLOW 7.5 comparing the actual groundwater level monitoring data from the field pumping test with the simulation data, the accuracy of the model was verified, and the water volume change of the sunken plaza was calculated. The low permeability of the curtain system calculated by a field test and the numerical model proved that the pumping activities in the sunken plaza had extremely low impact on the groundwater level outside the plaza. On the basis of this result, the pumping and seepage wells and water quality and quantity observation wells were designed scientifically and rationally. The purification and circulation control of water were realized in combination with rainwater, drainage, landscape, paving, and other facilities. According to the circulation system designed in this study, the annual water recycling capacity of the sunken plaza can reach more than 60,000 m3 , and the total suspended solids (TSS), chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) indicators in the rainwater can be reduced by more than 15% on average. The sunken plaza area forms a small spongy body that realizes water circulation, economic benefits, and ecological functions for the first time using groundwater storage. The developed method can be used for the water circulation and ecological construction of sunken plazas with similar geological environments. [ABSTRACT FROM AUTHOR]

APHA Standard methods 2130B and 2540D have proven valid and reliable methods to determine turbidity and total suspended solids (TSS). However, both methods have drawbacks and limitations. Carcinogenicity of formazin, inconsistency in preparation, and interference are the primary concerns in turbidity measurement. Equipment complexity, working steps, and measurement time are primary concerns in TSS measurement. The edge detection technique (EDT) is an alternative to overcome the drawbacks and limitations. This research aims to conduct the performance test of the proposed method using pro-analytical grade kaolin (Sigma-Aldrich K7375), which has non-toxic properties compared to the formazin standard. Natural water samples from three different sampling locations became another subject in the EDT-based measurement method performance test. Steps included are elemental characterization with SEM-EDS-JEOLJSM6510LA and particle size analysis with zeta sizer Horiba SZ-100. Turbidity measurement with Eutech TN100 and the TSS measurement with the gravimetric approach. Counted particle (CP) measurement through the EDT compared with the standard measurement. It showed that kaolin characteristics are closer to the natural suspension indicated by the more identical elemental compositions than the formazin elemental characteristics. Another result showed a correlation between kaolin concentration (KC), turbidity level, TSS concentration, and the counted particle is > 0.9. The proposed approach showed promising results indicated by the % Relative Standard Deviation < 20% for KC 0.5-20 mg/L and < 40% for KC 40-100 mg/L, in the linear range of 0.5-100 mg/L. Using a sample cell with a flat surface may improve the performance of the proposed approach. It is thus possible to reduce the reflection of light, which is a noise source in the measurement result. [ABSTRACT FROM AUTHOR]

The constant production of solids in intensive shrimp and tilapia culture can affect the performance of macroalgae when cultivated in an integrated system, and little is known about culture structures that enhance the performance of macroalgae in biofloc systems. The objective of this work was to evaluate different depths of culture structure for the macroalgae Ulva lactuca in an integrated system with Litopenaeus vannamei and Oreochromis niloticus in a biofloc system. The experiment lasted 70 days, with six systems composed of: a 16 m3 shrimp tank, a 3 m3 tilapia tank, and a 3 m3 macroalgae tank, with water recirculation between tanks. Two treatments were carried out, shallow float, with a structural depth of 10 cm, and bottom float, where the depth was kept at 30 cm from the surface. The shallow float resulted in a growth rate of up to 0.95 ± 0.54% day−1, with biomass loss only at the end of the culture due to the high density of macroalgae, decreasing temperature, and increasing solids concentration. The bottom float had biomass loss throughout the culture cycle. The integrated culture of shrimp, fish, and macroalgae is feasible with the use of shallow floats within 10 cm from the surface.

Jakarta Bay is a bay supporting the economy of thousands of nearby fishermen. Therefore, the reclamation in Jakarta Bay raises many environmental, economic, and social problems. During this reclamation, dredging and stockpiling activities increase the turbidity of the waters. This research aims to determine the changes in the distribution of total suspended solids (TSS) after reclamation using Sentinel 2A satellite imagery from 2016 to 2022. This research implemented the previous algorithm to produce the distribution of TSS in Jakarta Bay for attaining TSS values from Sentinel 2A satellite imagery processed by Google Earth Engine with overlay analysis method in a geographic information system. Spatial data were obtained by extracting TSS values using the previous estimation algorithm, namely the Budhiman algorithm, with a correlation coefficient of -0.745 and NMAE of 0.167. Based on the data processing results, it was found that the distribution of TSS from 2016 to 2022 was at a moderate level, which had a relatively significant influence on fisheries, requiring the fishermen to go to the open sea farther from the coast. This shows that reclamation carries no impact on the life of marine biota in Jakarta Bay.

The document "Certification Corner" from Opflow Online provides multiple-choice questions and answers related to water and wastewater treatment. It covers topics such as the impact of ozone on distribution systems, pipe collapse risks, flow measurement devices, and diffuser maintenance. The resource also includes information on emergency handling in wastewater utilities, diaphragm pump applications, chloramines, and oxygen uptake rates. Additional resources for certification exam preparation are listed at the end of the document. [Extracted from the article]

Septage refers to the semi-liquid waste material that accumulates in septic tanks and other onsite sanitation systems. It is composed of a complex mixture of human excreta, wastewater, and various solid particles. Septage is a potential source of water pollution owing to presence of high organic content, significant pathogen concentrations, and a range of nutrients like nitrogen and phosphorus. The harmful impacts of septage pollution poses significant risks to public health through the contamination of drinking water sources, eutrophication of water bodies and spread of water borne diseases. Conventional septage treatment technologies often face limitations such as high operational costs, energy requirements, and the need for extensive infrastructure. Therefore, with an aim to treat septage through an alternative cost effective and energy-efficient technology, a laboratory-scale constructed wetland (CW) system (0.99 m2) consisting of a sludge drying bed and a vertical flow wetland bed was utilized for the treatment of septage. The sludge drying bed and vertical flow beds were connected in series and filled with a combination of gravel with varying sizes (ranging from 5 to 40 mm) and washed sand. Canna indica plants were cultivated on both beds to facilitate phytoremediation process. The system was operated with intermittent dosing of 30 Ltrs of septage every day for 2 months. The HRT of the system was fixed at 48 h. The average inlet loads of Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), and Total Suspended Solids (TSS) were measured as 150 ± 65.7 g m−2 day−1, 713 ± 443.9 g m−2 day−1, and 309 ± 66.3 g m−2 day−1, respectively. After treatment, the final effluent had an average load of 6 g m−2 day−1 for BOD5, 15 g m−2 day−1 for COD, and 51 g m−2 day−1 for TSS, indicating that the CW system achieved an average removal efficiency of 88% for BOD, 87% for COD, and 65% for TSS. The average load of total coliforms and helminthes eggs in the influent was recorded as 4 × 108 Colony-Forming Units (CFU) m−2 day−1 and 3 × 107 eggs m−2 day−1, respectively. However, the CW system demonstrated significant effectiveness in reducing microbial contamination, with an average removal efficiency of 99% for both total coliforms and helminthes eggs. The vertical flow constructed wetland system, equipped with pretreatment by sludge drying bed, has proven to be efficient in treatment of septage. [ABSTRACT FROM AUTHOR]

A technique called biofloc technology (BFT) is an environmentally friendly method for aquaculture in which a successful growing cycle depends on the maintenance and monitoring of water quality parameters. Studies have revealed that improving water quality in BFT and maintaining the safety range of the parameters can help to increase the growth performance of cultured species. Following a systematic review of the literature, a meta-analysis was performed to explore how some important water parameters such as pH, dissolved oxygen (DO), nitrite (NO2–N), nitrate (NO3–N), ammonia (NH3–N), total ammonia nitrogen (TAN), total suspended solids (TSS), and alkalinity were influenced by different BFT systems. The PRISMA screening process was followed, and 33 studies were eligible for the meta-analysis. The meta-analyses showed that NO2–N and TSS were significantly affected by BFT, while pH, DO, NO3–N, NH3–N, TAN, and alkalinity were not significantly influenced by this system. The analyses revealed that NO2–N had a significant negative effect size due to BFT, whereas TSS showed a significant positive effect size. The study also revealed some publication bias in which few experiments of some studies showed extremely positive and negative effect sizes due to BFT application in the system. Overall, the findings suggest clear evidence of the profound influence of BFT on the water quality parameters in different aquaculture systems, suggesting the future development of BFT for sustainable and environmentally friendly aquaculture production. [ABSTRACT FROM AUTHOR]

Global climate change produces important shifts in the glacial runoff, modifying the relative contributions of meltwater and glacial clay discharges into headwater streams. Physical and chemical factors of glacier-fed streams are affected, such as total suspended solids (TSS), and nutrient concentrations. Here, we analyze the composition of the biofilm bacterial community by 16S rRNA sequencing along a glacier-fed network (Upper Río Manso) located in North Patagonian Andes (Argentina). We also analyzed changes in environmental factors in relation to the bacteria composition in different seasons (spring, summer, and autumn). Our results showed that the dominant phyla were Proteobacteria, Cyanobacteria, Bacteroidota, Actinobacteriota, and Acidobacteriota. Bacterial community composition changes longitudinally and seasonally in relation to glacial influence (TSS and phosphorus concentrations). We identified phylotypes of Proteobacteria (Polaromonas, Rhodoferax, and Methylotenera) that were only present in headwaters of the fluvial systems. In addition, Cyanobacteria also presented substantial changes along the main course of Manso River and among seasons. The increase of Cyanobacteria abundance was favored by the glacial influence both longitudinally and seasonally. Overall our results contribute to the understanding of the patterns of biodiversity and bacterial composition under a constant glacial retreat. [ABSTRACT FROM AUTHOR]

The objective of this study was to model the operation of a vertical-flow constructed wetland (VF-CW) for domestic wastewater, using Monte-Carlo simulations and selected probability distributions of various random variables. The analysis was based on collected wastewater quality data, including the values of the pollutant indicators BOD5 (biochemical oxygen demand), CODCr (chemical oxygen demand), and TSS (total suspended solids), in the 2017–2020 period. Anderson–Darling (A–D) statistics were applied to assess the fit of the theoretical distributions to the empirical distributions of the random variables under study. The selection of the best-fitting statistical distributions was determined using the percentage deviation (PBIAS) criterion. Based on the analyses that were performed, the best-fitting statistical distributions for the pollution indicators of the raw wastewater were the generalised extreme value distribution for BOD5, the Gaussian distribution for CODCr, and the log-normal distribution for TSS. For treated effluent, the log-normal distribution was the best fit for BOD5 and CODCr; the semi-normal distribution, for TSS. The new data generated using the Monte-Carlo method allowed the reliability of the VF-CW operation to be assessed by determining the reliability indices, i.e., the average efficiency of the removal of pollutants (η), the technological efficiency index (R), the reliability index (CR), and the risk index of the negative control of the sewage treatment plant operation (Re). The obtained results indicate that only in the case of CODCr, the analysed treatment facility may fail to meet the requirements related to the reduction of organic pollutants to the required level, which is evidenced by the values of the indicators CR = 1.10, R = 0.49, and η = 0.82. In addition, the risk index of the negative operation of the facility (Re) assumes a value of 1, which indicates that during the period of its operation, the VF-CW system will not operate with the required efficiency in relation to this indicator. The novelty of this work is the implementation of the indicated mathematical simulation methods for analysing the reliability of the operation of the domestic wastewater treatment facility. [ABSTRACT FROM AUTHOR]

Landowners and natural resource agencies are seeking to better understand the benefits of best management practices (BMPs) for addressing water quality issues. Using edge-of-field and edge-of-farm runoff analysis, we compared runoff volumes and water quality between small watersheds where BMPs (e.g., prescribed grazing, silvicultural practices) were implemented and control watersheds managed using conventional practices (i.e., continuous grazing, natural forest revegetation). Flow-weighted samples, collected over a 2-year period using automated samplers, were analyzed for nitrate/nitrite nitrogen (NNN), total Kjeldahl nitrogen (TKN), total phosphorus (P), ortho-phosphate phosphorous (OP), total suspended solids (TSS), and Escherichia coli (E. coli). Comparison of silvicultural planting to conventional reforestation practices showed a significant decrease in NNN loads (p < 0.05) but no significant differences in TKN, P, OP, TSS, or E. coli. Continuously grazed sites yielded >24% more runoff than sites that were under prescribed grazing regimes, despite receiving less total rainfall. Likewise, NNN, TSS, and TKN loadings were significantly lower under prescribed grazing management than on conventionally grazed sites (p < 0.05). Data suggests that grazing BMPs can be an effective tool for rapidly improving water quality. However, silvicultural BMPs require more time (i.e., >2 years) to establish and achieve detectable improvements. [ABSTRACT FROM AUTHOR]

Diverse plant life has been affected by the tropical environment, which includes high humidity and lots of rainfall. This research aimed to discover local plants to be used as biocoagulants in the treatment of coffee effluent. Three species of native plants were chosen: Trichantera gigantea (ketum ayam), Manihot esculenta (cassava plant) and Piper sarmentosum (kaduk). Coffee effluent was chosen because it has high total suspended solids (TSS), contributing to increasing turbidity that exceeds the allowable regulation limits. The coagulation-flocculation method was applied to remove these suspended solids and turbidity in the effluent using a jar test. These potential biocoagulants were extracted using distilled water before being screened and characterized to measure their amount of protein and polysaccharide contents using the Bradford and acid extraction approaches. The protein content for M. esculenta showed the greatest value (87.9 mg/g), while T. gigantea revealed the highest amount of polysaccharide extracted (37.0 mg/g). The optimum operating parameters were set at 300 rpm and 5 min for rapid mixing and then 180 rpm and 30 min for respective slow mixing with 30 min settling time. The findings show that P. sarmentosum was the best biocoagulant with the highest removal of TSS and turbidity at 51.0% and 66.9%, respectively. The mass ratio used in P. sarmentosum was lower when compared to other biocoagulants, which is 45.9 mg biocoagulant/g TSS, with the protein and polysaccharides contained in this biocoagulant were 11.6 mg/g and 34.0 mg/g, respectively. • Plant leaves as biocoagulant/flocculant agent in treating coffee industry effluent • Distilled water was used to extract proteins and polysaccharides from plant leaves • P. sarmentosum leaves contained highest protein with 11.6 ± 0.19 mg/g • Turbidity and total suspended solids were removed up to 66.9% and 51.0%, respectively • P. sarmentosum shows a great performance at a ratio of 45.9 mg biocoagulant/g TSS [ABSTRACT FROM AUTHOR]

Analysis of the comparison of noise levels with vehicle volume levels on Jl. Pahlawan Sidoarjo to Jl. Raya Legundi Krian. Kali Porong is used as a mud sewer for Lapindo to prevent damage to the mud retaining embankment. Lapindo's continuous mud disposal causes sedimentation in Porong River. The mud does not settle much along the river, but settles in the estuary of Kali Porong in the Madura Strait due to the flow of Lapindo mud and sediment transport from Kali Porong to the estuary and along the coast. This study suggests using Landsat 8 satellite images with the H. Wibisana (2021) algorithm to calculate Total Suspended Solid (TSS) levels. The results showed that the algorithm had a better correlation coefficient in 2018 (49.72%) and 2019 (69.065%). In 2020 and 2022, the Guzman-Santella (2009) algorithm gave the best results with correlation coefficients of 84.297% and 64.18%, respectively. In 2023, Ety Parvati's (2014) algorithm has a correlation coefficient of 79.18%. This research can be a reference for future research and help map the distribution of TSS and monitor changes in TSS. This will provide appropriate solutions in decision-making related to environmental impacts and development around the area. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the effectiveness of a natural biological treatment system for wastewater using Red soil, Arka Darshan, Arka Tilak, Arka Nirantara, and Arka Prajwal plants. The system employs clay as a natural nanomaterial for adsorption of substances such as nitrates, phosphates, potassium, and heavy metals. The soil contains numerous microorganisms that decompose organic matter into simpler compounds, while the plants use phytoremediation to uptake heavy metals and nutrients. The study measured the system’s efficiency in reducing Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Suspended Solids (TSS), Total Dissolved Solids (TDS), Phosphate, Magnesium, Zinc, Nitrate, Sodium, and Potassium. The results showed that the system had an average efficiency of 98% in COD and 96% in BOD removal, and contributed an efficiency of 99% TSS and 46% TDS. The system also removed nitrates and phosphates, which cause eutrophication in water bodies, by 76% and 72%, respectively. Additionally, heavy metals like chromium, Nickel and Zinc were reduced by up to 81%, 71% and 59%. The study suggests that the natural biological treatment system is a sustainable and effective alternative to conventional wastewater treatment, particularly in sparsely populated rural areas. Therefore, we can conclude that this system has potential for wider adoption in treating wastewater. [ABSTRACT FROM AUTHOR]

Stakeholders developing water quality improvement plans for lakes and reservoirs are challenged by the sparsity of in‐situ data and the uncertainty ingrained in management decisions. This study explores how satellite images can fill gaps in water quality databases and provide more holistic assessments of impairments. The study site is an impaired water body that is serving as a pilot for improving state‐wide nutrient management planning processes. An existing in‐situ database was used to calibrate semi‐analytical models that relate satellite reflectance values to turbidity and total suspended solids (TSS). Landsat‐7 images from 1999 to 2020 that overpass High Rock Lake, North Carolina were downloaded and processed, providing 42 turbidity and 39 TSS satellite and in‐situ match‐ups for model calibration and validation. Model r‐squared values for the fitted turbidity and TSS models are 0.72 and 0.74, and the mean absolute errors are 14.6 NTU and 3.2 mg/L. The satellite estimates were compared to the in‐situ data and simulated TSS values produced by a calibrated hydrologic‐hydrodynamic model. The process‐based model is considered less accurate than the satellite model based on statistical performance metrics. Comparisons between data sources are illustrated with time series plots, frequency curves, and aggregate decision metrics to highlight the dependence of lake impairment assessments on the spatial and temporal frequency of available data and model accuracy. [ABSTRACT FROM AUTHOR]

This study presents the results of a simulation work performed using an activated sludge model to investigate the effects of reactors' hydraulic retention times (HRT) on phosphorus removal in a hypothetical anaerobic-oxic (AO) process. The simulations were performed for low, medium, and high influent phosphorus loads corresponding to influent C/P ratios of 100/1.0, 100/1.5, 100/2.0. For each of influent phosphorus loads, various anaerobic volume fractions (AVF) between 0.125 and 0.625 were used to test the response of the process that was investigated as a result of the change in hydraulic retention times. Additionally, removal efficiencies for chemical oxygen demand (COD), total nitrogen (TN), total phosphorus (TP), and total suspended solids (TSS) were also calculated. As a result of the study, maximum COD removal efficiencies for 100/2.0, 100/1.5 and 100/1.0 influent C/P ratios were determined as 91.8% for 0.250 AVF (for 100/2.0 and 100/1.5), and 91.7% for both 0.125 and 0.250 AVF, respectively. In all influent C/P ratios, the maximum TN removal efficiency was determined as 56.3% at 0.625 AVF, and the maximum TSS removal efficiency was determined as 93.3% at 0.125 AVF. Maximum TP removal efficiencies were determined as 92.8%, 90.8% and 86.2% for 100/2, 100/1.5 and 100/1 input C/P ratios at 0.375 AVF, respectively. Results showed that total phosphorus (TP) removal efficiency is determined by both influent C/P ratio and AVF in AO process. Of these, the effect of AVF is more prominent. For efficient removal of phosphorus, AVF ratios of 0.25 to 0.375 should be employed. [ABSTRACT FROM AUTHOR]

Inland and coastal waters provide key ecosystem services and are closely linked to human well-being. In this study, we propose a semi-analytical method, which can be applied to Sentinel-2 MultiSpectral Instrument (MSI) images to retrieve high spatial-resolution total suspended solids (TSS) concentration in a broad spectrum of aquatic ecosystems ranging from clear to extremely turbid waters. The presented approach has four main steps. First, the remote sensing reflectance (R rs) at a band lacking in MSI (620 nm) is estimated through an empirical relationship from R rs at 665 nm. Second, waters are classified into four types (clear, moderately turbid, highly turbid, and extremely turbid). Third, semi-analytical algorithms are used to estimate the particulate backscattering coefficient (b bp) at a reference band depending on the water types. Last, TSS is estimated from b bp at the reference band. Validation and comparison of the proposed method with three existing methods are performed using a simulated dataset (N = 1000), an in situ dataset collected from global inland and coastal waters (N = 1265) and satellite matchups (N = 40). Results indicate that the proposed method can improve TSS estimation and provide accurate retrievals of TSS from all three datasets, with a median absolute percentage error (MAPE) of 14.88 %, 31.50 % and 41.69 % respectively. We also present comparisons of TSS mapping between the Sentinel-3 Ocean and Land Colour Instrument (OLCI) and MSI in Lake Kasumigaura, Japan and the Tagus Estuary, Portugal. Results clearly demonstrate the advantages of using MSI for TSS monitoring in small water bodies such as rivers, river mouths and other nearshore waters. MSI can provide more detailed and realistic TSS estimates than OLCI in these water bodies. The proposed TSS estimation method was applied to MSI images to produce TSS time-series in Lake Kasumigaura, which showed good agreements with in situ and OLCI-derived TSS time-series. [ABSTRACT FROM AUTHOR]

Low impact developments (LIDs) are control measures to restore the hydrologic regime and enhance stormwater quality. Due to LID's expensive capital and maintenance cost, the placement of LID controls in a watershed is an important planning task and still an open question in the specialized literature. This study proposes a simulation-optimization approach to place bioretention systems within a watershed to optimize their effectiveness. The Stormwater Management Model (SWMM) and the Non-dominated Sorting Genetic Algorithm III (NSGAIII) were coupled to identify the near-optimal locations of bioretentions for near-optimal quality and quantity controls, considering runoff volume, peak flow, total suspended solids, total nitrogen, and cost. Trade-offs were identified between cost versus other objective functions. The results suggest no specific spatial preference in placement of bioretentions under different rainfall regimes in watershed scale. However, in subcatchment scale, the near-optimal placement under single storm events is either maximum or none, while distributed under continuous simulation. [ABSTRACT FROM AUTHOR]

To solve the upcoming environmental problems, sponge city concepts as well as new technologies are being developed these days. One of the future challenges is to reduce drinking water demand by using decentralized water recycling systems. This study aimed to investigate the performance of a specially designed pilot wetland roof (PWR) treating domestic greywater (GW) at ground level under outdoor conditions and to evaluate the effects of different hydraulic loading rates (HLRs) for a period of two years. The results showed highly efficient removal of typical greywater pollutants from the system, e.g., five-day biochemical oxygen demand (BOD5) > 96%, chemical oxygen demand (COD) > 93%, total suspended solids (TSS) >94%, anionic surfactants (AS) > 94%, ammonium-nitrogen (NH4-N) > 84%, total nitrogen (TN) > 71%, total phosphorous (TP) > 87%, and E. coli (1.86 ± 1.54 log-removal). The mean concentrations of the targeted parameters at the outflow were in compliance with the requirements for discharge to the environment and met reclaimed water quality standards for agricultural irrigation, except for E. coli. Statistically significant (p < 0.05) results of pollutant mass removal rate across different HLRs indicated the potential effect of HLR on treatment performance, and HLR in a range of 67–80 L m–2 d–1 contributed to a higher removal efficiency without compromising the limit values. A comparatively low HLR of 45 L m–2 d–1 should be applicable if pathogen removal is the most important requirement. Plant species showed good plant vitality and adapted well to the water storage mat. The higher the mean ambient air temperature, the greater runoff reduction (>50%) was observed due to high evapotranspiration. The results showed the system is a promising green technology for GW recycling and can be scaled up for application to urban buildings. [ABSTRACT FROM AUTHOR]

The article presents the possibility of reducing fees for wastewater discharge from combined sewer overflows (CSOs) into the aquatic environment by minimizing the load emission of total suspended solids (TSS) and chemical oxygen demand (COD). The analysis was conducted based on limiting the wastewater volume discharged to the receiving water by one of the viable options, i.e., raising the overflow crest. The assessment was made on the example of the functioning J1 CSO in Lodz (in Polish: Łódź) in the years 2013-2015. An analysis of rainfall recorded in the J1 catchment area was also performed for this period. For the determination of the TSS and COD load emitted to the receiver, a predictive model based on rainfall parameters and the volume of discharged wastewater was used. To determine the wastewater volume emitted during individual activations of the J1 overflow, the model of the sewer network serving this catchment was calibrated in the EPA SWMM software. Simulations were conducted, considering different heights of the weir crest (static change). The results of the analyzes showed that raising the crest by 5 cm reduced the total fee for the J1 activity by 35% compared to its existing height in 2013 and about 40% for 2015. Raising the crest by 10 cm in 2015 enabled, for example, the J1 overflow activity to be in accordance with the applicable law. Reducing the amount of wastewater discharged to the receiver by using the overflow crest height adjustment method presented in the article may bring measurable financial and ecological benefits. [ABSTRACT FROM AUTHOR]

A 70‐day experiment was carried out to evaluate biofloc system operation with no carbon addition by manipulating dietary protein and lipid levels for Nile tilapia (Oreochromis niloticus) cultivation. Three treatments were conducted; Control treatment (C; fed on a 30% crude protein [CP] diet supplemented with 3% vegetable oil [VO] + addition of external carbon source [ECS] in rearing tank), low protein–low lipid treatment (LPLL; fed on 23% CP diet supplemented with 3% (VO) + no addition of ECS) and low protein–high lipid treatment (LPHL; fed on 23% CP diet supplemented with 9% VO + no addition of ECS). The C treatment recorded the highest values (p < 0.05) in terms of final body weight (FBW), specific growth rate, floc volume, total suspended solids, and ammonia nitrogen. No significant differences were observed between C and LPHL treatments regarding FBW and protein efficiency ratio. The liver sections of LPHL treatment showed better values for histological alteration index compared to the control. It could be concluded that applying a biofloc system with no carbon addition using LPHL diets may afford better water quality conditions, limit the environmental impact and decrease dietary costs with limited effect on fish performance. [ABSTRACT FROM AUTHOR]

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Irrigation water quality impacts plant growth, crop production, and public health. Thus, understanding the trends in irrigation water quality is important to manage public health, and optimize crop production. The Koga region in Ethiopia is a developing area where crops are an important food source for a growing population, and irrigation is critical to supply additional food crops and secure food insecurity issues. This study measures physiochemical and biological parameters to assess the suitability of Koga irrigation water for crops intended for human consumption. In March 2022, irrigation water samples were collected and analyzed for physicochemical and biological qualities. Kelley's ratio, magnesium danger, and sodium absorption ratio were calculated from the data obtained. Results showed that the turbidity (174.33–259.00 NTU), total suspended solids (80.33–175.00 mg/L), total alkalinity (143.33–195.33 mg/L), total hardness (150.67–224.6 mg/L), SO42−(43.96–73.00 mg/L), PO43−(56.27–87.43 mg/L), and BOD5 (63.23–95.40 mg/L) levels surpassed the recommended limit of FAO(35 NTU,50 mg/L,100 mg/L,100–150 mg/L,20 mg/L,3 mg/L and 30 mg/L, respectively). BOD5 levels of the tested water samples exceeded the permissible limit set by the EU (10 mg/L). The coliform and fecal coliform levels in all sampled waters were higher than the zero/100 mL limits of the EU and WHO set for irrigation water. The studied water samples were found to be unsuitable for the cultivation of crops and vegetables since TA, PO4−3, and NO3− levels exceeded the tolerance limit of the crops and vegetables cultivated in the site, while the coliform and BOD5 levels surpassed their tolerable limits. Consequently, it is not recommended to eat crops and vegetables without first properly preparing them. The results showed improper ratio of Mg2+:Ca2+ and Na+:Ca+2, and a magnesium hazard was foreseen. This study showed that the turbidity, total suspended solids, total alkalinity, total hardness, SO42−, PO43−, BOD5, and the coliform levels of the studied irrigation water samples of the Koga irrigation project were not found within the safe limits of FAO, WHO, EU, and irrigation water quality limits of different nations, even though additional samples evaluating seasonal fluctuations are needed to fully assess the water quality. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate the water quality, growth performance, body composition, length–weight relationship, condition factors and benefit–cost analysis of giant freshwater prawn (Macrobrachium rosenbergii) cultured with biofloc system in pond conditions. The experiment was conducted in twelve (12) experimental ponds, each measuring 240 m2. The control group was cultured without any biofloc (T1), and biofloc‐based three treatments were biofloc with 100% feed (T2), biofloc with 90% feed (T3) and biofloc with 80% feed (T4). The biofloc‐based treatments showed significantly higher floc volume, total suspended solids, total heterotrophic bacteria and plankton density than the control (p < 0.05). All the growth parameters were significantly higher in biofloc‐based treatments (T2, T3 and T4) than in the control (T1). The lowest feed conversion ratio was found lowest in T4 (1.40 ± 0.02) and highest in T1 (2.13 ± 0.04), which was significantly different among the treatments (p < 0.05). The significantly highest production was obtained 939.02 ± 6.61 kg/ha in T2, and the lowest was 779.67 ± 7.50 kg/ha in T1. The length–weight relationship indicated positive allometric growth in all treatments. The condition factor ranged from 0.95 to 1.07, showing that the prawns were in good health throughout all treatments. The results of the present study indicated that M. rosenbergii can adapt to a biofloc‐based aquaculture system, and the conventional feeding rations can be reduced up to 20% without affecting the growth and production. [ABSTRACT FROM AUTHOR]

A wastewater treatment plant (WWTP) is an essential part of the urban water cycle, which reduces concentration of pollutants in the river. For monitoring and control of WWTPs, researchers develop different models and systems. This study introduces a new deep learning model for predicting effluent quality parameters (EQPs) of a WWTP. A method that couples a convolutional neural network (CNN) with a novel version of radial basis function neural network (RBFNN) is proposed to simultaneously predict and estimate uncertainty of data. The multi-kernel RBFNN (MKRBFNN) uses two activation functions to improve the efficiency of the RBFNN model. The salp swarm algorithm is utilized to set the MKRBFNN and CNN parameters. The main advantage of the CNN-MKRBFNN-salp swarm algorithm (SSA) is to automatically extract features from data points. In this study, influent parameters (if) are used as inputs. Biological oxygen demand (BODif), chemical oxygen demand (CODif), total suspended solids (TSSif), volatile suspended solids (VSSif), and sediment (SEDef) are used to predict EQPs, including CODef, BODef, and TSSef. At the testing level, the Nash–Sutcliffe efficiencies of CNN-MKRBFNN-SSA are 0.98, 0.97, and 0.98 for predicting CODef, BODef, and TSSef. Results indicate that the CNN-MKRBFNN-SSA is a robust model for simulating complex phenomena. [ABSTRACT FROM AUTHOR]

Juwana et al. [[1]] evaluated water quality programs aiming to achieve pollution reduction through uncertainty and sensitivity analysis of the Citarum River, Indonesia. Remote sensing technology with large-scale synchronous observations in the Pearl River Delta in China have also been used to effectively monitor total nitrogen (TN) [[4]]; however, TN is a non-optically active substance, so it is difficult to retrieve TN through analysis methods. When water pollution is a severe issue, forecasting water quality to control water pollution and informing consumers in the event of the detection of poor water quality is crucial. At a low discharge rate, deposited sediment on the pipe bottom changed the hydraulic roughness and magnitude of the dispersion coefficient at low Reynolds numbers (close to the laminar flow), but water quality models often assume turbulent flow. [Extracted from the article]

The search for alternative solutions for sustainable management of faecal sludge in the area of dewatering with biocoagulants/bioflocculants remains unfulfilled. Some available and accessible indigenous plants in the northern part of Ghana have been characterised and subsequently evaluated in their suitability for use as biocoagulant/bioflocculants. The Yila (Crossopteryx febrifuga) and the Voulo (Grewia mollis) plants were the indigenous plants used in this study. Three applications from the Yila wooden stem, the Yila bark, and the Voulo at different treatment concentrations with faecal sludge were monitored. The Yila wooden stem gave a potential of pollutant removal up to about 83.99%, 93.79%, and 91.54% for Chemical Oxygen Demand (COD), Total Suspended Solids (TSS), and turbidity, respectively. Application of the Yila bark gave a respective removal efficiency of up to about 77.39%, 82.02%, and 54.60% for COD, TSS, and turbidity. The efficiency of the Voulo plant obtained for COD, TSS, and turbidity was up to about 80.43%, 86.83%, and 72.55%, respectively. No cyanogenic or toxic compounds were identified in the characterised raw materials used for this study. The study has revealed the potential of producing biocoagulants that can perform as effectively as synthetic/chemical coagulants using locally natural raw materials but the use of it at large scale will only be applicable for batch or semi-batch systems. Some interesting constituents identified in the plants under consideration, such as trialkyl bismuthine and furan derivative, can open up opportunities to elucidate the potential applications of these identified plants in the areas of pharmaceuticals, cosmetics, glass and ceramics, rubber production, and other applicable medicinal advantageous areas. [ABSTRACT FROM AUTHOR]

Background: The application of index of biotic integrity (IBI) to evaluate river health can be an essential method for river ecosystem management. However, these types of methods were developed in small, low-order streams, and are therefore, infrequently applied to large rivers. To that end, phytoplankton communities and environmental variables were monitored in 30 sampling segments of the middle and lower reaches of the Yangtze River, China during the wet (July–August) and dry (November–December) seasons in 2017–2018. We developed a phytoplankton-based index of biotic integrity (P-IBI) and used the index to assess the ecological health of the Yangtze River. Relationships among P-IBI, its component metrics, and environmental factors were analyzed across different seasons. Results: Results obtained from the P-IBI indicated that the phytoplankton-based ecological health of the Yangtze River was rated as "good" during both seasons, with an overall better condition in the dry season. During the wet season, there were scattered river segments with P-IBI ratings of "fair" or below. Water quality and land use appeared to shape the patterns of P-IBI. In the wet season, P-IBI negatively correlated with total phosphorus, nitrate, total suspended solids, turbidity, conductivity, and dissolved oxygen. In the dry season, P-IBI positively correlated with total nitrogen, ammonium, and nitrite, and negatively correlated with water temperature. Conclusions: The ecological health of the Yangtze River as reflected by the P-IBI exhibited spatial and temporal variability, with the effect of water quality being greater than that of local land use. This study indicated the importance of considering seasonal effects in detecting large river ecological health. These findings enhanced our understanding of the ecological health and characterized potential benchmarks for management of the Yangtze River. These findings also may be applicable to other large rivers elsewhere. [ABSTRACT FROM AUTHOR]

In this study, the performance of pervious concrete in improving runoff quality is investigated. Limestone powder was employed as a substitute for cement to evaluate the replacement of this material to improve the quality of the runoff. COD (chemical oxygen demand), BOD (biological oxygen demand), EC (electrical conductivity), TSS (total suspended solids), and turbidity tests are all part of environmental runoff tests. Runoff from plain pervious concrete (PPC) and pervious concrete containing 15% limestone powder were used to determine the efficacy of removing each of these pollutants (PCL15). In all cases, the results showed that PCL15 was more efficient than PPC at removing pollutants. It was found that the PCL15's highest removal efficiency was 72 percent, which is related to turbidity. The statistical analysis of pollution removal efficiency in PPC and PCL15 runoff showed a significant difference between these averages. [ABSTRACT FROM AUTHOR]

The efficiency of a hybrid upflow anaerobic sludge blanket reactor (HUASB) where coconut fiber is used as an inert media was investigated under different hydraulic residence times (started with 6 h and then decreased to 2 h) with varied organic loading rates (ranged from 0.5 to 6.0 kg chemical oxygen demand (COD)/m−3day−1). The 3.5-L lab-scale reactor was used for sewage treatment under mesophilic conditions for 8 months. The COD reduction varied from 74%±1.7% to 61%±2.4% , the total suspended solids (TSS) reduction was in the range of 72%±2.2% to 54%±2.7% , and the methane content in the biogas was 65.1%±0.3%. An attempt has been made to understand the performance of the lab-scale reactor for primary population of microorganisms using a microscopic technique. Different groups of anaerobic bacteria and granulation were visualized and quantified using unstained observations, Gram staining, ocular micrometry (granular size determination), Neubauer's chamber (counting of microorganisms), and scanning electron microscopy. Correlation analysis among the various operational parameters has also been prepared. Overall, the performance of the HUASB reactor using coconut fiber appears to be a cost-efficient sewage treatment alternative in developing nations. A HUASB is a high-rate anaerobic treatment process that consists of a suspended and attached growth treatment method. The treatment unit can sustain a high organic loading because it has a high biomass content and good sludge-settling characteristics. The study investigates the effectiveness of a HUASB reactor using coconut fiber as a novel inert media for sewage treatment. Based on the findings, this technology can be applied at a sewage treatment facility. This treatment also has the potential for reduced environmental and economical footprints. [ABSTRACT FROM AUTHOR]

SARS-CoV-2 wastewater surveillance (WWS) at wastewater treatment plants (WWTPs) can reveal sewered community COVID-19 prevalence. For unsewered areas using septic tank systems (STSs) or holding tanks, how to conduct WWS remains unexplored. Here, two large STSs serving Zuma Beach (Malibu, CA) were studied. Supernatant and sludge SARS-CoV-2 concentrations from the directly-sampled STSs parameterized a dynamic solid–liquid separation, mass balance-based model for estimating the infection rate of users. Pumped septage before hauling and upon WWTP disposal was also sampled and assessed. Most (96%) STS sludge samples contained SARS-CoV-2 N1 and N2 genes, with concentrations exceeding the supernatant and increasing with depth while correlating with total suspended solids (TSS). The trucked septage contained N1 and N2 genes which decayed (coefficients: 0.09–0.29 h−1) but remained detectable. Over approximately 5 months starting in December 2020, modeled COVID-19 prevalence estimations among users ranged from 8 to 18%, mirroring a larger metropolitan area for the first 2 months. The approaches herein can inform public health intervention and augment conventional WWS in that: (1) user infection rates for communal holding tanks are estimable and (2) pumped and hauled septage can be assayed to infer where disease is spreading in unsewered areas. [ABSTRACT FROM AUTHOR]

The objective of the present study was to evaluate the effectiveness of a natural biological treatment unit. Red soil was used as structural support to the plants materials of four different Arka varieties in the treatment unit. The study also sought to ascertain the efficiency of the treatment facility in lowering various contaminants such as heavy metals- chromium, nickel, zinc, and nutrients like nitrate and phosphate as well as Total Suspended Solids (TSS), Biochemical Oxygen Demand (BOD) and Chemical Oxygen Demand COD etc. Analytical results of the study demonstrated that the wastewater treatment was highly perceptible with an average efficiency of 98% for COD and 96.5% for BOD, displaying the ability of natural materials to break down organic matter in the wastewater. TSS was significantly reduced by the treatment as well, with an efficiency of 75%, while TDS and TS were showed less than 50% efficiency. In addition, 67% and 60% efficiency was observed for nitrates and phosphates respectively that are known to contribute eutrophication in aquatic ecosystem. Apart from this biological treatment unit was successful in lowering chromium metal concentration with an efficiency of up to 90%. The obtained result findings of our study, plainly signposted that the natural biological treatment of wastewater is a workable and sustainable alternative to conventional treatment. The natural biological treatment could be ideal for sparsely populated rural areas with limited access to conventional wastewater treatment facilities. [ABSTRACT FROM AUTHOR]

The scarcity and change in water quality reinforce the need to reuse effluents in water intensive industries as the petrochemical ones. In this article, the tertiary effluent from a Petrochemical Complex in Southern Brazil was used as feed water in a pilot unit with a capacity of 1 m³.h−1 to produce industrial water to be reused as clarified or demineralized water (ultra-pure water). For the treatment, an integrated system composed of ultrafiltration (UF), reverse osmosis (RO) and electrodeionization (EDI) was used. The parameters evaluated were aluminum, calcium, chloride, electrical conductivity (EC), color, chemical oxygen demand (COD), iron, magnesium, pH, total suspended solids (TSS), sulfate and turbidity. The UF/RO system operated with average permeate fluxes of 6.6 and 6.7 L.h−1.m−2, respectively. For the EDI, the operational parameters (flow rate, electric current and EC in the feed water) were optimized, considering the percentage of conductivity removal (%RC) as a response, by using response surface methodology (RSM) based on a central composite design (CCD). The best predicted values of flow rate, electric current and conductivity of the feed water were 6.6 L.min−1, 1.27 A, and 22.2 µS.cm−1, respectively. The %RC predicted in the software was 98.2%, similar to the mean value at the midpoint 97.1%. The EDI system was operated with the model conditions, and the product water reached the necessary quality to be reused as demineralized water in the Southern Petrochemical Complex in Brazil. Industrial reuse can reduce 20% raw water collection and 70% of the effluent volume disposed in the soil, thus reducing the water footprint, and increasing the sustainability of the petrochemical industry. [ABSTRACT FROM AUTHOR]

In Ghana, small-scale mining (SSM) has been carried out for many years, generating employment and income. Currently, illegal artisanal mining ('galamsey') has impacted the environment negatively, resulting in land degradation and water pollution. The government of Ghana, responding to public outcry against the negative effects of 'galamsey', placed a ban on illegal small-scale mining activities in March 2017. This ban stopped both 'legal' small-scale and the illegal artisanal miners from carrying out any such activity. In July 2018, this study was carried out to examine the status of water and sediment quality in eight endemic regions of illegal mining to ascertain the outcome of the ban on the water quality of the rivers. Methodologies in the Standard Methods for the Examination of Water and Wastewater were followed. Results of the study indicated that the rivers were high in total suspended solids (TSS), turbidity and colour, suggesting inflow of wastewater from the illegal mining activities and some run-off. Colour had a strong correlation with turbidity (r = 0.95) and TSS (r = 0.94), suggesting that the pollution originates from the same sources. Low levels of metals were found in both water and sediment. However, very high concentrations of Fe were detected in both water and sediment. Mercury concentrations were low in the water column but relatively higher in the sediment. A comparison of the general water quality status of the water bodies in the Pra Basin in 2013 and 2018 using the Water Quality Index (WQI) showed a marginal improvement in quality in 2018 over 2013 in the Pra Basin. The improvement of water quality in 2018 is attributable to the ban. [ABSTRACT FROM AUTHOR]

Blood clam or blood cockle (Anadara granosa) is a clam species with high calcium carbonate (CaCO 3) and chitin content; these compounds are commonly used in coagulation water treatment. This study examined the capacity of blood cockle shells (BCS) as an innovative natural coagulant in the form of unmodified powder (BCSP) and chitosan extracted from the shells (BCSC) to reduce TSS and turbidity of well-water. SEM and FTIR analysis were conducted to analyse the characteristics of the media. The coagulant dose, pH of the water sample, and settling time were investigated using a jar test experiment to determine the optimum condition for each experimental system. Rapid mixing (1 min at 120 rpm) was followed by slow mixing (10 min at 60 rpm), followed by settling times ranging from 10 to 30 min. The optimum settling time was 30 min, after which 76% TSS and 76% turbidity were removed using 75 mg/l of BCSP at pH 4. The tests with BCSC resulted in 80% TSS and 81% turbidity removal with 200 mg/l of BCSC at pH 5 and a settling time of 30 min. The results were compared to the performance of alum (Al 2 (SO 4) 3 ·18H 2 O), a commercial chemical coagulant. Under similar dosage (200 mg/L) and pH (= 6) conditions, alum reduced turbidity and TSS by 95% and 97%, respectively. These results indicate that blood cockle shell-based coagulant is a promising environmental-friendly material that can compete and possibly replace conventional chemical coagulants in water treatment systems. [ABSTRACT FROM AUTHOR]

The current study focuses on investigating how to improve the efficacy of the combined process of aerated lagooning and adsorption for the treatment of olive mill wastewater (OMWW) from the olive industries in the Loukkos region using the design of experiments approach. The latter made it possible to optimize the experimental conditions, such as the mass concentration of lime, the mass concentration of powdered activated carbon (AC), and the speed of agitation (Va), which are required for the envisaged treatment, in order to control the results after the evaluation of the necessary physicochemical parameters, namely pH, total suspended solids (TSS), chemical oxygen demand (COD), rate of discoloration, and content of polyphenols. The experimental conditions necessary to carry out this study were between 1.4 and 1.75 g/l for AC, between 23 and 32 rpm for the stirring speed, and between 0.88 and 1.3 g/l for the mass concentration of lime. The results of this experiment showed that treating OMWW with the prototype II after adding lime to the mixture resulted in an estimated 85% reduction in the analyzed parameters. The pH, TSS, COD, discoloration rate, and polyphenol content were all reduced from initial values of 4.87, 0.63 (g/l), 80.3 (g (O2/l)), 0.8%, and 1.45 (g/l), respectively, to final values of 6.92, 0.12 (g/l), 12, 0.16%, and 0.25 (g/l). These results are highly significant when compared to those obtained during the treatment of prototype I using only powdered activated carbon, which showed a reduction rate of around 70%. [ABSTRACT FROM AUTHOR]

Litopeneaus vannamei is the most preferable species for culture by shrimp producers due to short time crop, hardy species and high market value. Present investigation was carried out to comprehend the significance of the carbon and nitrogen ratio in shrimp farming systems at Ankola, Uttara Kannada (District) and Haleyangadi, Mangaluru (Taluk) and Dakshina kannada (District). The pond water characteristics namely temperature, pH, alkalinity, salinity, Dissolved oxygen, biological oxygen demand, total suspended solids, total dissolved solids, Ammonia, NO2, NO3, PO4, SiO3 were found to vary from 28 to 35°C, 6.9 to 9.4, 25 to 125 mg/l, 0 to 36 ppt, 0 to 4.20mg/l, 0.020 to 0.259mg/l, 1.63 to 81.24mg/l, 0.12 to 36.45μg at./l as micromole per litre, 0.09 to 11.12 μg at./l, 0.26 to 32.15μg at./1, 0.15 to 26.18μg at./l, 2.40 to 90.18μg at./l respectively. The pond soil characteristics comprising of pH, organic carbon were ranged from 6.5 to 8.6, 0.235 to 1.994%, respectively while texture comprising of sand content varied from 48.41 to 96.26%, clay 0.3 to 2.45% and silt 3.14 to 51.24%. C/N ratio is varied 1.084-11.450 during the research phase. The outcomes of the water quality parameters shown quite higher nutrient all selected ponds and Organic carbon showed high in all ponds along with day of culture that’s impact data on water quality and influence on pond biomass and the C/N ratio. A culture system's ability to produce more can be greatly increased by maintaining the quality of the soil and water by removing toxicity though nitrification and continuous monitoring. [ABSTRACT FROM AUTHOR]

This research aimed to identify water quality changes in the Cirata Reservoir and the factors affecting them in terms of hydrology and climate. The sampling was carried out in both the rainy and dry seasons at 12 locations in the Cirata Reservoir. The Mann–Whitney U-test (different test) results showed that salinity, total suspended solids (TSS), the potential of hydrogen (pH), nitrate (NO3-N), phosphate (PO4), nitrate and phosphate content in the sediment were significantly different (α < 0.05) between the rainy and dry seasons. The principal component analysis (PCA) results showed that the water quality characteristics in the Cirata Reservoir in the dry season were influenced by environmental conditions in the reservoir, especially by the floating cage aquaculture and climate conditions. The high solar radiation, low rainfall, and floating cage aquaculture increased the pH and amounts of dissolved oxygen (DO), ammonia (NH3-N), PO4, nitrate and phosphate in the sediment while decreasing transparency, salinity, TSS, and NH3-N. During the rainy season, the high runoff from Citarum Watershed controlled the water quality characteristics of the Cirata Reservoir. In this season, transparency, salinity, pH, DO, NH3-N, PO4, nitrate and phosphate in the sediment increased, while TSS tended to be low. In general, the water volume addition decreased the nutrition and salinity concentration in the water body. However, a distinct phenomenon occurred in the Cirata Reservoir. The runoff from agriculture, settlement, livestock, and the Citatah Karst in the Upper Citarum Watershed increased nutrition and salinity in the reservoir. Land use in the Citarum Watershed and floating cage aquaculture had an important role in the reservoir water quality. [ABSTRACT FROM AUTHOR]