Coliform Concentrations Research Articles

Distributions of Fecal Indicators at Aquaculture Areas in a Bay of Republic of Korea.

Aquaculture products, such as clams, scallops, and oysters, are major vectors of fecal-derived pathogens. Male-specific and somatic coliphages are strongly correlated with human noroviruses, the major enteric viruses worldwide. Geographic information system with local land-use patterns can also provide valuable information for tracking sources of fecal-derived pathogens. We examined distributions of four fecal indicator microorganisms, i.e., male-specific and somatic coliphage, total coliform, and Escherichia coli (E. coli) in three river and seawater sampling sites located on the coast of Gomso Bay in the Republic of Korea during the sampling period (from March 2015 to January 2016). Geospatial analyses of fecal indicators and correlation between environmental parameters and fecal indicators or among fecal indicators were also performed. Overall, river water samples showed highest concentrations of both types of coliphage in summer (July 2015). High concentrations of both total coliform and E. coli were detected in river water during the period from July to September 2015. High concentrations of all fecal indicators were found at site GL02, located in the innermost part of Gomso Bay, which has high-density agriculture and residential areas. Environmental factors related to precipitation-cumulative precipitation on and from 3 days before the sampling day (Prep-0 and Prep-3, respectively)-and salinity were strongly correlated with concentrations of all fecal indicators. The present results suggest that investigations of multiple fecal indicators with a systemic geospatial information are necessary for precisely tracking fecal contaminations of aquaculture products.

Effect of Eco-enzyme on Water Quality Parameters in Some Rivers Disembogued at Ambon Bay

Due to the increasing population in Ambon City, the high volume of organic waste in rivers that empties into Ambon Bay can impact the marine ecosystem. On the other hand, processing organic waste in the form of eco-enzymes has been widely applied and has benefits, for instance, as a cleaning liquid. This study aimed to analyze the effect of eco-enzyme concentrations on water quality parameters, such as pH, ammonia, detergent, coliform, nitrate, phosphate, BOD, COD, and DO in several rivers flowing into Ambon Bay. The research was conducted from May to November 2022. Water samples were collected from four rivers that flow into Ambon Bay. Production of ecoenzyme was carried out at the Marine Science Laboratory at Pattimura University for three months. Eco-enzyme derived from banana peels obtained from tourist areas on Ambon Island. The research applied the method of observation and experiment. The data of each parameter obtained from the treatments (sample before and after treatment using 10% and 20% of eco-enzyme) were then compared with Second-Class of River Water Quality Standards. The results showed that eco-enzyme could neutralize the pH value. The DO, ammonia, detergent and coliform concentration decreased after adding 10% and 20% of the eco-enzyme. By contrast, adding eco-enzyme to the river watercan increase the concentration of nitrate, phosphate, BOD, and COD.

Clarifying the mechanism of peroxydisulfate and sulfite activated by Fe2+ for waste activated sludge pretreatment: Enhancement of dewaterabiliy, removal of antibiotic resistance genes and pathogenic microorganisms

The remarkable performance of SO4•— based advanced oxidation processes in improving waste activated sludge (WAS) dewatering has recently received considerable attention. However, its potential effect on the removal of emerging pollutants is often overlooked. In this study, two types of pretreatment methods (S2O82-/Fe2+ and SO32-/Fe2+) were employed to comprehensively evaluate their performance in improving the dewatering of WAS and the removal of antibiotic resistance genes (ARGs) and pathogenic microorganisms. At the optimal dosage of 1.2/1.5 mmol-S2O82-/Fe2+/g-VS, the capillary suction time reduction rate of WAS after S2O82-/Fe2+ was 1.8 times than that of SO32-/Fe2+. Notably, both S2O82-/Fe2+ and SO32-/Fe2+ could remove the 12 types of ARGs identified in WAS. Nonetheless, S2O82-/Fe2+ was more effective in removing ARGs, with a range of removal rate (0.96–2.17 log-units), and reduced the propagation and proliferation potential of residual ARGs. Furthermore, the coliforms content in WAS after S2O82-/Fe2+ decreased significantly with a minimum of 1.84 ± 0.24 log (MPN/g-TS) compared to SO32-/Fe2+. Further analysis indicated that the redistribution of bound extracellular polymeric substances (EPS) in WAS, especially the variations in protein, was the key factor affecting the dewaterability. In contrast to SO32-/Fe2+, the S2O82-/Fe2+ could quickly destroy the EPS structure to release bound water, accelerate the dissociation of WAS flocs, and cause cell lysis and DNA dissolution because of the continuous production and accumulation of SO4•— in the hostile conditions inside. Therefore, S2O82-/Fe2+ is an efficient, economical, and green method to improve WAS dewatering and the removal of pollutants.

Salinity and microbiological risk assessment in surface runoff and main tributaries to La Vega Dam in Teuchitlán, Jalisco, Mexico.

Objective: This research aimed to evaluate the water quality of the main tributaries to the La Vega Dam for irrigation purposes through the physicochemical and microbiological parameters. Design/methodology/approach: The 10 main tributaries to the La Vega Dam were selected. The variables evaluated were pH, Temperature, Electrical Conductivity, Total Dissolved Solids and Dissolved Oxygen, boron calcium, magnesium, sodium, SAR, and RCS. Results: 50% of samples presented low sodicity risk, 10% medium risk, 20% and 20% very high risk. In the CSR results, only one site (10%) presented a low risk, and the remaining four tributaries (40%) of this area presented a medium risk. Five sites (50%) located east of the dam presented a high risk. Also, high boron concentration was observed, corresponding to El Salado River. Fecal pollution was detected in 100% of sites, limiting their use as irrigation water. Limitations on study/implications: Continuous water quality monitoring of the main tributaries to and into La Vega Dam should be followed up. Findings/conclusions: The most significant contribution of contamination to the dam was observed in the eastern part, with the entrance of El Salado River. High concentrations of boron were also observed. A high concentration of total and fecal coliforms was also found, in addition to the presence of Pseudomonas spp., which indicates fecal contamination. The effluent at the east of La Vega Dam is unsuitable for irrigation.

The Potential of Spring Water Analysis for Drinking Water at Ujung Gagak Village, Kampung Laut Subdistrict, Cilacap Regency

Limited clean water is the main problem in Ujung Gagak Village. The community can use no groundwater because the water is brackish and salty, which is unsuitable for daily activities. This study aims to analyze the potential of the Karang Cave spring to be used as drinking water. This spring plays an important role in the life of the people of Ujung Gagak Village when the dry season arrives. Using the grab sampling method, raw water sampling at the Karang Cave spring. Pollution Status Index (IP) quality of 5.08 is included in the moderately polluted category. Then, raw water samples are taken and processed in the Reverse Osmosis (RO) system. Parameters that exceeded the quality standard were total coliform of > 24,000 CFU/100ml, salinity parameter of 0.33‰, turbidity of 1.98 NTU, and hardness of 320 mg/L. However, treating it in an RO system for drinking water is necessary. Laboratory test results for water quality after processing, several parameters experienced a significant decrease, for the parameter salinity to 0‰, turbidity to 0.74 NTU, and hardness to 99 mg/L, total coliform decreased by 108 CFU /100ml. The results showed that the RO system succeeded in removing salt up to 99.5% and reducing the Concentration of turbidity, hardness, and total coliform. It is suitable for drinking water, but if you want to drink it immediately, you can cook it first, considering that the total coliform is still above the required quality standard.

How does the citizens' choice of water use actions based on their empirical knowledge affect the water quality in a rural community of the Philippines?

This research assessed water quality, based on the purpose of water consumption, in households in the municipality of Barbaza, the Province of Antique, Philippines, according to the national water quality guidelines. The effects of the empirical/traditional water use actions taken by local people on the quality of the water they use were investigated through a descriptive study using water quality measurements. Most of the drinking water in the community did not meet the required standards of pH, total dissolved solids (TDS), or coliform. Tap water and well water samples generally met the pH and TDS standards. However, Escherichia coli (E. coli) and coliform were detected, and nitrogen pollution in well water was also confirmed. Local practices, such as using old clothes as filters for well pumps, increased the coliform concentration from 0-10 CFU/mL to too numerous to count (TNTC) levels of more than 100 CFU/mL. Storing well water in a bucket also affected both E. coli and coliform concentrations. Such empirical/traditional water use actions create a high risk of exposing local people to harmful microorganisms. This research integrated citizen science into the methodology for local water management, which could assist governors, practitioners, and citizens, particularly in Southeast Asia, where strong community relationships exist.

Effect of water treatment processes on microbial contamination in drinking water in rural areas of the urban periphery

ABSTRACT The water treatment infrastructure facilities play an important role in ensuring the safety of drinking water. A survey of the drinking water treatment process was conducted in the urban peripheral areas of Beijing, China, and the main water treatment infrastructure facilities in terms of their impact on microbial contamination were investigated. The sedimentation equipment, filtration facilities, and disinfection equipment are all significantly correlated with the concentration of heterotrophic plate counts in drinking water. The filtration facilities and disinfection equipment were also positively correlated with the concentration of total coliform and Escherichia coli. The effect of removing microorganisms by different water disinfection methods gradually decreases in the order of ozone, chlorine, chlorine dioxide, and ultraviolet light. The effect of microbial contamination removal of different water pumping methods is as follows: direct water supply > pressure tank > secondary pressing pump station > water tower > high-level water tank, and the removal effects are 7.6, 7.4, 4.1, 3.6, and 1.7 times that of self-flowing water supply. The study provides scientific support for the renovation, and upgrading of microbial pollution reduction in drinking water in rural areas of the urban periphery.

The Effect of Pollution Source Distance, Construction, and Behavior of Dug Well Users on Total Coliform Content

Dug well is a water source that is located relatively close to the ground surface so it is prone to pollution. This research aims to analyze the effect pollution source distance, construction and behavior of dug well users on total coliform content in Karangturi Village. Data collection was carried out by examining samples of dug well water in the laboratory, observing and measuring well construction, and using questionnaires to measure the behavior of well users. The research results show that 23 (95.8%) wells have a total coliform >0 MPN/100ml and 1 (4.2%) well have a total coliform content of 0 MPN/100ml. Simultaneously (p value=0.106) the variable distance to the pollutant source and partially (p value= 0.998) each livestock pen and septic tank variable do not have a significant influence on the total coliform content. Simultaneous well construction (p value= 0.489) and partially (p value= 0.999) of each well construction variable did not have a significant effect on the total coliform content. The behavioral variable simultaneously (p value= 0.346) and partially the knowledge variable (p value= 1.000), the attitude variable (p value= 0.999), and the attitude variable (p value= 0.999) did not have a significant effect on the total coliform content.

Enhancement of solar water disinfection using different types of clay

This study delves into the impact of incorporating natural nanoparticles (mineral clays) into contaminated water during the Solar water disinfection (SODIS) process. The experiment involved introducing contaminated water samples into glass containers containing 1 × 10−3 gm/ml of a specific clay type. These containers were then exposed to solar radiation for varying time intervals. Subsequently, samples were extracted from each container, and the total counts of Total Coliform, P. aeruginosa aeruginosa, and E.coli were measured using the IDEXX setup. The results revealed that Zeolite, a specific type of clay, exhibited the shortest disinfection process among the mineral clay samples. The optimal concentration of Zeolite, which effectively reduced the concentration of Total Coliform, P. aeruginosa, and E.coli concentration, was 1 × 10−3 gm/ml. In conclusion, adding Zeolite to wastewater was observed to positively impact the disinfection process, accelerating the inactivation process by reducing the number of pathogenic microorganisms.

Analysis of Spatiotemporal Variation and Driving Factors of Water Quality in the Xiangjiang River Basin from 1990 to 2016

In order to explore the spatiotemporal variation characteristics and driving mechanism of water quality in the Xiangjiang River Basin, the data of 16 water quality parameters at 113 stations over 26 years from 1990 to 2016 in the Xiangjiang River Basin were collected for synthetically assessing the water quality and identifying its main pollutants through the water quality index and other methods. The causal mechanism of water quality, especially the driving effect of water level and land use pattern, was analyzed. The results showed that： ① The overall water quality grade of the Xiangjiang River Basin during the study period was "good." However, the water quality deteriorated first （from 1990 to 2003） and then improved （from 2004 to 2016）. The season variation in water quality was not obvious, but the water quality fluctuation of the wet season was larger. The water pollution load of the main stream decreased successively from the middle reaches, downstream reaches, and upstream reaches. The upstream tributaries had the best water quality, whereas areas with poor water quality were mainly distributed at the mouth of the middle and downstream tributaries, especially in areas where multiple tributaries converged. ② Toxic heavy metals had the characteristics of toxicity, persistence, and bioaccumulation. If they exceeded a certain concentration in water, they were difficult to purify, posing great harm to the natural environment and human health. The toxic metal index （CI1） was the leading factor affecting water quality, in which Hg and Cd were the main parameters affecting the overall water quality of the Xiangjiang River Basin. ③ The water level had a positive impact on the water quality of the Xiangjiang River by diluting environmental parameters. Land type had little effect on heavy metal concentration, whereas forest land could improve water quality. Grassland had a negative correlation with permanganate index over a large scale range （≥ 5 km）. The increase in water bodies, arable land, and impermeable surface areas within the watershed increased the probability of high fecal coliform concentration in the water body. ④ With the increase in buffer distance, the water quality explained by the land use pattern increased. On the scale of 10 km buffer zone in the riparian zone, the explanation degree by land use pattern on water quality was the highest, which was an effective scale for water quality control of the Xiangjiang River. This research showed that the driving factors of heavy metal pollution and other pollution were different, but their regional differences were all obvious in the Xiangjiang River Basin. Therefore, pollution control should be classified and taken according to local conditions.

Development of a “big data” groundwater microbial contamination index and spatial comparisons with enteric infection rates in southern Ontario

Big data have become increasingly important for policymakers and scientists but have yet to be employed for the development of spatially specific groundwater contamination indices or protecting human and environmental health. The current study sought to develop a series of indices via analyses of three variables: Non-E. coli coliform (NEC) concentration, E. coli concentration, and the calculated NEC:E. coli concentration ratio. A large microbial water quality dataset comprising 1,104,094 samples collected from 292,638 Ontarian wells between 2010 and 2021 was used. Getis-Ord Gi* (Gi*), Local Moran's I (LMI), and space-time scanning were employed for index development based on identified cluster recurrence. Gi* and LMI identify hot and cold spots, i.e., spatially proximal subregions with similarly high or low contamination magnitudes. Indices were statistically compared with mapped well density and age-adjusted enteric infection rates (i.e., campylobacteriosis, cryptosporidiosis, giardiasis, verotoxigenic E. coli (VTEC) enteritis) at a subregional (N = 298) resolution for evaluation and final index selection. Findings suggest that index development via Gi* represented the most efficacious approach. Developed Gi* indices exhibited no correlation with well density, implying that indices are not biased by rural population density. Gi* indices exhibited positive correlations with mapped infection rates, and were particularly associated with higher bacterial (Campylobacter, VTEC) infection rates among younger sub-populations (p < 0.05). Conversely, no association was found between developed indices and giardiasis rates, an infection not typically associated with private groundwater contamination. Findings suggest that a notable proportion of bacterial infections are associated with groundwater and that the developed Gi* index represents an appropriate spatiotemporal reflection of long-term groundwater quality. Bacterial infection correlations with the NEC:E. coli ratio index (p < 0.001) were markedly different compared to correlations with the E. coli index, implying that the ratio may supplement E. coli monitoring as a groundwater assessment metric capable of elucidating contamination mechanisms. This study may serve as a methodological blueprint for the development of big data-based groundwater contamination indices across the globe.

Conditions of total coliform in the Aur River, Palembang City, South Sumatra, Indonesia

Pathogenic microorganisms present in river water pollution are a serious health risk. Escherichia coli is a pathogen commonly found in water. Escherichia coli is an indicator of water contaminated with feces. These pathogens have an impact on human health. Aur River is one of the tidal rivers in Palembang City. From the observations, many people dispose of domestic waste into river bodies, so the river is at risk of being polluted by pathogenic microorganisms. When it recedes, the water looks pitch black, and when it is high, many people bathe, brush their teeth, and wash their clothes in this river. Thus, this study aimed to monitor water quality, including total coliform, of the Aur River Palembang City. The results of this monitoring can be used as the basis for making a policy and strategy to control the quality of this river water. This study was carried out on the Aur River, which is 2.5 km long. Measurements were made at three stations, namely at the upstream, middle, and downstream. Based on measurements of the pH, BOD, COD, DO, and total coliform concentrations, it is concluded that the Aur River has been polluted because the BOD, COD, DO, and total coliform were above the quality standards. The pH is still at the quality standard.

Monitoring microbial safety and evaluation of removal efficiency from drinking water in Ahvaz, Iran

The availability of potable water sources is vital worldwide. Due to the potential for microbial contamination, developing nations focus more research on the existence of microorganisms that are indicators in water than they do on chemical presence. This study was done in order to assess the microbial level of drinking water in Ahvaz city. In this descriptive-cross-sectional study, the measure the microbial tests, two culture mediums, MacConkey broth, and green lactose broth, were used for possible and confirmatory culture respectively. Bioindicators measured in drinking water included fecal coliform and total coliform. Not only the residual chlorine concentration was also measured, but its relationship with bioindicators was also calculated by Spearman's correlation test. Result of this study showed that, the maximum total coliform concentration reported is between 2021 and 2022 (1600 MPN/100 ml). Based on result of this study the average concentration of fecal coliform in 2019, 2020, 2021, and 2022 were 11.88, 10.66, 7.78, and 6.11 MPN/100 ml respectively. The average annual concentration of total coliform and fecal coliform in four years was 28.95 and 9.32 MPN/100 ml, respectively. According result of this study, the Karun River, Ahvaz's main drinking water source, is contaminated by surface water runoff, old facilities, and unfiltered discharge of different wastewater kinds from factories, farms, and communities in Khuzestan.

Intelligent dosing of sodium hypochlorite in municipal wastewater treatment plants: Experimental and modeling studies

Sodium hypochlorite (NaClO), a disinfectant extensively employed in municipal wastewater treatment plants (WWTPs), is frequently overdosed to ensure qualified effluent quality consistently. In light of the escalated disinfectant expenses and detrimental environmental impacts, it is critical to have a precise control model in place to enable intelligent dosing of NaClO. The lack of real-time disinfection evaluation indicators presents difficulties in precisely and swiftly regulating the dosage. Herein, the CT value (the product of residual chlorine concentration and contact time) was initially determined experimentally as a metric for assessing disinfection in municipal WWTPs. Fecal coliform (FC) concentrations become less than 1.0 × 103 MPN/L when the effluent CT value is regulated at 0.20 mg·min/L (calculated as Cl2). In addition, a model employing long short-term memory (LSTM) was developed to predict the dosage, utilizing simplified and suitable parameters such as COD, NH3-N concentration, flow rate, and historical dosage of NaClO as input factors, which demonstrated satisfactory performance (R2 = 0.948). Notably, dosage adjustments were made concurrently in response to CT value feedback. The intelligent dosing model under simultaneous feedforward and feedback control was applied at a full-scale WWTP for nearly two months, considerably reducing disinfectant consumption and meeting the discharge standard of FC.

Occurrence and Mitigation of Bacterial Regrowth in Stored Household Water in Eastern Coastal Madagascar

In communities where people lack on-demand, safely managed drinking water, stored household water often becomes contaminated by fecal bacteria, regardless of the source-water quality. The objectives of this paper are to assess and control bacterial contamination in stored household water in Toamasina, a rapidly urbanizing city in eastern coastal Madagascar. We collected samples of source water and stored household water from 10 representative households that use different water sources and different storage strategies, and we analyzed the samples for several fecal indicator bacteria. We also tested three methods that residents of Toamasina could realistically employ for cleaning their household water storage vessels, assessing the effect of the cleaning methods on measured bacterial levels in the water. Consistent with the previous literature, we found that concentrations of total coliforms in stored household water were significantly higher than in the corresponding source water (p &lt; 0.05). In 100% of households that stored their water in 20 L polyethylene jerrycans (n = 4), biofilms on the walls of the jerrycan harbored total coliforms and Enterococcus. The use of a closed storage container was, on its own, not found to provide a meaningful protective effect against bacterial regrowth; to be protective, closed storage containers must be combined with high-quality source water and/or with adequate cleaning to prevent biofilm formation. A dilute solution of sodium hypochlorite, known locally as Sûr’Eau or Manadio Rano, was both the most effective and the least expensive method for cleaning household water storage containers. We conclude that regular and effective cleaning of storage containers is an essential component of safe water storage. Because household storage of collected water is common in many low- and middle-income countries, these results are important towards the worldwide achievement of the United Nations’ Sustainable Development Goal 6.

Potensi Pemanfaatan Enzim Biokatalitik dari Kulit Buah dan Sayur untuk Pengolahan Limbah Cair Rumah Sakit

Health services in hospitals produce hazardous and infectious waste that comes from sharing sources of activity. The research carried out experimentally in laboratory aims to determine the effect of biocatalytic enzyme treatment from fruit and vegetable peel (concentration variations of 5%, 10%, 15%) on pH, chemical oxygen demand (COD) levels, total suspended solids (TSS), and total coliforms of hospital liquid waste. From the research results, it was found that the addition of biocatalytic enzymes was very effective in reducing the total coliform concentration. The highest reduction in coliforms occurred with the addition of 15% enzyme, where there was a decrease from 1600 MPN/100 mL to 500 MPN/100 mL at a digestion time of less than 24 hours. After a digestion time of 2 days, no coliforms were found in the wastewater samples. However, there was a decrease in pH and an increase in TSS and COD concentrations which did not meet quality standards after being treated with enzymes at all concentration variations. The profile of changes in TSS and COD concentrations shows a decreasing trend with an increase in digestion time of 1 to 3 days, the values ​​obtained will still exceed the TSS and COD quality standards (30 mg/L and 100 mg/L). Meanwhile, the waste pH gradually increased with increasing digestion time up to 3 days at enzyme concentrations of 5% and 10%, namely 3.5 and 4.8. However, this value is still outside the permitted quality standard interval, namely 6-9.

Assessing the utility of shellfish sanitation monitoring data for long-term estuarine water quality analysis

Regular testing of coastal waters for fecal coliform bacteria by shellfish sanitation programs could provide data to fill large gaps in existing coastal water quality monitoring, but research is needed to understand the opportunities and limitations of using these data for inference of long-term trends. In this study, we analyzed spatiotemporal trends from multidecadal fecal coliform concentration observations collected by a shellfish sanitation program, and assessed the feasibility of using these monitoring data to infer long-term water quality dynamics. We evaluated trends in fecal coliform concentrations for a 20-year period (1999–2021) using data collected from spatially fixed sampling sites (n = 466) in North Carolina (USA). Findings indicated that shellfish sanitation data can be used for long-term water quality inference under relatively stationary management conditions, and that salinity trends can be used to investigate management-driven bias in fecal coliform observations collected in a particular area.

Detection of thermotolerant coliforms and SARS-CoV-2 RNA in sewage and recreational waters in the Ecuadorian coast: A call for improving water quality regulation.

Wastewater surveillance represents an alternative approach to regulating contamination and the early detection of infectious agents and outbreaks of diseases of public health importance. This study evaluated domestic wastewater effects on recreational waters in estuarine and seawater bodies in Guayas and Santa Elena provinces in Ecuador, South America. Fecal indicator bacteria (thermotolerant coliforms) served as key indicators for evaluation. Physical, chemical, and microbiological quality markers following the Ecuadorian environmental quality standard and the discharge of effluents to the water resource were analyzed. Samples were collected from 44 coastal sites and 2 oxidation lagoons during the dry and rainy seasons of 2020 and 2021, respectively. SARS-CoV-2 RNA was detected in samples with higher E. coli concentrations using reverse transcription quantitative PCR to detect the genes N and ORF1ab. All samples analyzed for SARS-CoV-2 showed Ct ˂ 40 for at least one gene. Four samples showed at least 20 genome copies of gene N per reaction. These were at an artisanal fishing port, an estuarine area (Palmar), a recreational bay, and an oxidation lagoon. A moderate correlation was found between SARS-CoV-2 RNA, thermotolerant coliform and E. coli (p-value ≤ 0.0037), and a strong and positive correlation between thermotolerant coliform and E. coli. (p-value ≤ 0.00001), highlighting the utility of these established parameters as a proxy of the virus. Significant differences were found in the concentrations of thermotolerant coliforms between seasons (p-value = 0.016) and sites (p-value = 0.005). The highest levels of coliforms were found in the dry season (63000 MPN/100 mL) in Anconcito and during the rainy season (14000 MPN/100 mL) at Esterillo in Playas County. It is recommended that the decentralized autonomous governments of the surveyed provinces in Ecuador implement urgent corrective actions and establish medium-term mechanisms to minimize a potential contamination route. Additional parameters must be included in the monitoring, such as Enterococcus and intestinal parasites, due to their public health implications. In the oxidation lagoons, maintenance actions must be carried out, including the dissolution of sediments, an increase in water retention times, and in situ treatment of the sludge, to improve the system's performance.

Revitalizing Water Health: Unraveling Coliform Dynamics in Banjar Regency's River Ecosystem

This study examined total coliform levels in rivers in Banjar Regency, South Kalimantan, and their effects on water quality and public health. Water samples were taken at eight river observation points using purposive sampling in a field survey. Analysis compared total coliform results to health criteria. To determine the link between total coliform and DO, correlation tests were performed. The overall coliform concentration exceeded the class I quality limit of 50 CFU/100 mL with 5050 to 52833,335 CFU/100 mL. Total coliform levels correlated -0.878 with DO levels, demonstrating contamination's ecological effects. High total coliform levels make river water unfit for sanitation and hygiene. Banjar Regency waterways must be cleaned to reduce bacterial contamination, protect public health, and allow safe water use. Addressing these issues will improve local prosperity and water sustainability

Impact of operational conditions on drinking water biofilm dynamics and coliform invasion potential.

The revelation that even low concentrations of coliforms can infiltrate into mature drinking water biofilms highlights a potential public health concern. Nowadays, the measurement of coliform bacteria is used as an indicator for fecal contamination and to control the effectiveness of disinfection processes and the cleanliness and integrity of distribution systems. In Flanders (Belgium), 533 out of 18,840 measurements exceeded the established norm for the coliform indicator parameter in 2021; however, the source of microbial contamination is mostly unknown. Here, we showed that mature biofilms, are susceptible to invasion of Serratia fonticola. These findings emphasize the importance of understanding and managing biofilms in drinking water distribution systems, not only for their potential to influence water quality, but also for their role in harboring and potentially disseminating pathogens. Further research into biofilm detachment, long-term responses to operational changes, and pathogen persistence within biofilms is crucial to inform strategies for safeguarding drinking water quality.