Fecal Coliform Concentrations Research Articles

Mikrobiološka kvaliteta morske vode i dagnje (Mytilus galloprovincialis, Lamarck 1819) u priobalju Dubrovnika (jugoistočni Jadran)

This research was conducted between March 2016 and March 2017 as the first study on the water and mussel quality in the coastal area of Dubrovnik (Croatia). Bacteriological analyses were conducted simultaneously on wild mussels (Mytilus galloprovincialis) tissue and their ambient water. The total numbers of heterotrophic bacteria, total coliforms, faecal coliforms and faecal streptococci in the water were determined. Concentrations of Escherichia coli were measured in mussel. The investigated stations are located in coastal water, which is particularly influenced by climatic and anthropogenic factors interacting at the boundaries between the land and freshwater and seawater environments. Seasonal variables, such as rainfall and riverine network characteristics, determine the delivery of bacteria (including E.coli) to coastal water. Direct methods of assessing the density of heterotrophic bacteria at all sampling stations showed the characteristics of an oligotrophic area. The abundance of faecal coliform bacteria was in all cases higher within mussel tissue than in the surrounding water where levels were sometimes undetectable. Maximum E. coli concentrations in mussels and seawater were regularly recorded through the summer, with the exceptions of April 2016 and January 2017 at two stations following precipitation. Minimum faecal coliform concentrations were recorded in the winter.

Exploration of the driving factors and distribution of fecal coliform in rivers under a traditional agro-pastoral economy in Kyrgyzstan, Central Asia

Fecal coliform (FC) in river water is one of the threats to human health. To explore the pollution status of FC in rivers of Kyrgyzstan, a mountainous country with traditional agro-pastoral economy, 184 water samples from the rivers of Kyrgyzstan in low and high river flow period were analyzed. Spatial autocorrelation and classical statistical methods were used to analyze the spatiotemporal distribution and driving factors of FC. The results showed that the surface water quality of Kyrgyz rivers was good, and the concentration range of FC was 0–23 MPN/100 mL. Temporally, the maximum FC concentration was 4 MPN/100 mL in low river flow period, while in the period of high river flow, the highest value reached to 23 MPN/100 mL. Spatially, the concentration of FC in high altitude areas was low, while that in the lowland areas was relatively high, which indicated that animal husbandry in high altitude areas contributed little to FC in rivers, and urban domestic sewage and agricultural activities in lowlands were the main pollution sources of FC in rivers. There was no correlation between FC and hardness, electrical conductivity (EC), pH and total organic carbon (TOC) in river water of Kyrgyzstan, and the distribution of FC in high river flow period was mainly driven by population and human modification of terrestrial systems. The results can provide a basis for the prevention and control of surface water FC pollution and related diseases in Kyrgyzstan.

DETERMINATION OF SURFACE WATER QUALITY BASED ON MACROZOOBENTHOS BIODIVERSITY AND THE PREVALENCE OF TREMATODES CERCARIAE IN FRESHWATER MOLLUSCS

Lake Cisanti is the upstream of Citarum River and silting has occurred in the inlet areas. This water body was selected as the research area due to its crucial role for people living in West Java Province despite some pollution issues recently. The research was conducted from January to May 2016 during rainy season. The aim of it was to assess water quality of Lake Cisanti and reveal that Trematodes cearcariae could be used as bio indicator of organic pollution. From identification results, there were 31 morphospecies of macrozoobenthos from seven classes found in Lake Cisanti. Melanoides tuberculata had the highest total density (188 ind/m2). It implied that organic matter due to open defecation polluted Lake Cisanti. Based on the value of CCMEWQI, H’, and FBI, it can be concluded that water quality of Lake Cisanti comprehensively was unpolluted during January-May 2016. Water conductivity and organic carbon of sediment had the strongest correlation with macrozoobenthos biodiversity in Lake Cisanti. In order to comprehensively understand the main factors of physical and chemical parameters of water and sediment parameters influencing macrozoobenthos biodiversity, Principal Component Analysis (PCA) was required. Based on PCA results, there were two main factors of water parameters, F1 (consist of turbidity and COD) and F2 (consist of temperature and conductivity). Those could explain 73.268% variance of all water parameters. Furthermore, the overall prevalence of Trematode cercariae in Molluscs was about 5.49%. There was significant and strong correlation between prevalence of Trematodes cercariae and fecal coliform concentration based on Spearman correlation analysis. It implied that Trematodes cercariae could be considered as a bio indicator of organic pollution, even though a further research is needed to test it in various aquatic ecosystems, both laboratory (man-made ecosystem) and natural ecosystem scales.

Physicochemical characterization of wastewater from the Al-Hoceima slaughterhouse in Morocco

In the context of the current policy of sustainable management of water resources, the forecasting of pollution risks and the protection of these resources are of paramount importance. For this purpose, the quality of these resources must be safeguarded in the medium and long term. Industrial development in Morocco has made this situation worrying for all socio-economic actors. In recent years, this economic growth has been marked by the establishment of slaughterhouses that discharge their liquid waste into watercourses or sewage networks. These discharges are likely to destabilize the environmental balance in the years to come, hence the need to take responsibility for treating all sources of pollution. The clean-up of these discharges requires several steps from the identification of the various pollutants to their treatment. This is why this initial work was carried out to characterize the wastewater from the Al-Hoceima slaughterhouse and to assess the performance of the treatment plant at this slaughterhouse. The results of the physicochemical analyses showed that the wastewater generated by this slaughterhouse is characterized by a neutral pH of 7.47, a high organic load of 1280 mg O2 L-1 COD, and a remarkable suspended solids content of 259 mL-1. Regarding the performance of the wastewater treatment plant connected to this slaughterhouse; The results show that this plant operates very efficiently, eliminating 65% of the COD, 70.6% of the BOD5 and 65.44% of the TSS, thus eliminating the organic matter, which is 67.82%. For the microbiological charge of these wastewater, the results showed that at the entrance the concentrations of fecal coliforms are 1×106 UFC mL-1, 15×107 UCF mL-1 fecal streptococci and 15×105 for yeast. The effluents discharged by the treatment plant comply with Moroccan standards.

Surface Water Quality Differs between Functionally Similar Restored and Natural Wetlands of the Saint Lawrence River Valley in New York

We tested the hypothesis that upland wetland restorations provide the same quality of wetland, in terms of ecosystem services and biodiversity, as natural wetlands in the St. Lawrence River Valley. Water quality (pH, alkalinity, colored dissolved organic matter, phytoplankton community composition, chlorophyll-a, fecal coliform, total phosphorus, dissolved nitrate, turbidity, specific conductivity) in 17 natural and 45 restored wetlands was compared to determine whether wetland restoration provided similar physicochemical conditions as natural wetlands in the Saint Lawrence River Valley of northeastern New York State. Natural wetlands were more acidic, which was hypothesized to result from the avoidance of naturally acidic regions by farmers seeking to drain wetlands for crop and pasture use. Natural wetlands had significantly greater fecal coliform concentrations. Restored wetlands had significantly greater specific conductivity and related ions, and this is attributed to the creation of wetlands upon marine clay deposits. Other water quality indicators did not differ between restored and natural wetlands. These findings confirm other research at these same wetlands showing no substantial differences between restored and natural wetlands in major biotic indicators. Thus, we conclude that wetland restoration does result in wetlands that are functionally the same as the natural wetlands they were designed to replicate.

Effect of seasonal variation on the occurrences of high-risk pharmaceutical in drain-laden surface water: A risk analysis of Yamuna River

The occurrence of pharmaceutical residues in the aquatic ecosystem is an emerging concern of environmentalists. This study primarily investigated the seasonal variation of high-priority pharmaceutical residues in the Yamuna River, accompanied by 22 drains discharge from different parts of Delhi. Five sampling sites were selected for analyzing high-priority pharmaceuticals along with physico-chemical and biological parameters for 3 season's viz. pre-monsoon (PrM), monsoon (DuM), and post-monsoon (PoM), respectively. The maximum occurrences were detected during the PoM, compared to the PrM and DuM seasons. The maximum concentration of BOD, COD, and Phosphate was detected at the last sampling station (SP-5). Similarly, all targeted pharmaceuticals concentration were maximum at the last sampling point i.e. Okhla barrage (SP-5, max: DIC = 556.1 ng/l, IBU = 223.4 ng/l, CAR = 183.1 ng/l, DIA = 457.8 ng/l, OFL = 1726.5 ng/l, FRU = 312.2 ng/l and SIM = 414.9 ng/l) except at Barapulla downstream (SP-4, max: ERY = 178.1 ng/l). The mean concentrations of Fecal coliform (FC) ranged from 1700 to 6500 CFU/100 ml. The maximum colonies were detected in PrM season (6500 CFU/100 ml) followed by PoM (5800 CFU/100 ml) and least in DuM (1700 CFU/100 ml). Risk quotient (RQ) analysis of high-priority pharmaceuticals indicated high ecotoxicological risks exposure (>1) from DIC, DIA, OFL, and SIM in all seasons at all the sampling sites. However, lower risk was predicted for IBU, CAR, ERY, and FRU, respectively. This risk assessment indicated an aquatic ecosystem potentially exposed to high risks from these pharmaceutical residues. Moreover, seasonal agricultural application, rainfall, and temperature could influence the levels and compositions of pharmaceutical residue in the aquatic ecosystem. Hence, attention is required particularly to this stream since it is only a local lifeline source for urban consumers for domestic water supply and farmers for cultivation.

Multivariate Analyses of Selected Hydro-bacterial Variables along the Longitudinal Gradient of Orani River, Philippines

There is paucity of environmental data for Orani river systems in Bataan (Philippines) despite its regional economic and ecological significance. The present study conducted multivariate analyses of various water quality parameters and selected bacterial communities to evaluate the river’s health integrity. River data exhibited spatial and seasonal variation, with observed significantly distinct heterotrophic and Gram-negative bacterial counts in the midstream and downstream against upstream samples. Fecal coliform concentrations were statistically different in the sequence: upstream < downstream < midstream. Multivariate Principal Component Analysis identified the most important variables affecting the variability in bacterial concentrations among the sampling groups (81.64% variation). Cluster analysis also revealed the associations and similarities of sampling groups based on abundance of bacterial loadings. Further, water quality indices were classified within “marginal” class (54.77 for wet season; 57.67 for dry season). The hydrological index estimated a score of 47.97 for wet season that described as “suitable with high restriction” class (30<(HI)c<55), and 62.24 for dry season in the “suitable with medium restriction” class (55<(HI)c<75).

Potentially pathogenic bacteria isolated from Paipa cheese and its susceptibility profiles to antibiotics and biocides.

The objective of this work was to evaluate the microbiological quality of cheese produced by formal and informal micro-enterprises in Paipa, Colombia, to isolate potentially pathogenic bacteria and to determine their prevalence and resistance to antimicrobials such as antibiotics and biocides. Sixteen micro-enterprises of the seventy existing in the region were sampled during 3years. Viable concentrations of aerobic mesophiles, total and fecal coliforms, Salmonella sp., Listeria monocytogenes, Staphylococcus sp., yeasts, and molds were determined. Seventy-three bacterial isolates were identified by 16S rRNA gene sequencing. The susceptibility of the isolates to antibiotics and biocides was determined. The results indicated that between 98 and 100% of the cheese samples (n = 48 samples) of formal and informal micro-enterprises presented populations of total and fecal coliforms and Staphylococcus sp. above the limits established by Colombian regulations and varied according to the micro-enterprise. The results also indicated that 56% of Staphylococcus isolates were S. aureus. L. monocytogenes was positive in 38% of the samples. Salmonella sp. was not detected. The coliforms that prevailed were Escherichia coli (25%), Citrobacter freundii (14%), and Proteus mirabilis (8%). All L. monocytogenes were sensitive to ampicillin but resistant to erythromycin and trimethoprim-sulfamethoxazole. S. aureus isolates were susceptible to most antibiotics, except tetracycline and erythromycin (7% resistance). Likewise, 30% of coliforms (n = 36) were multidrug-resistant to antibiotics but susceptible to biocides.

Water quality of Puyo River and tributaries, Pastaza, Ecuador

This research was developed in the sub-basin of the Puyo River, Province of Pastaza, Ecuador, in the years 2015 and 2018 had as objective: To characterize the environmental quality of water, in different sectors of the sub-basin of the Puyo River, including the main tributaries. The zones were classified as high, urban and low. A monitoring was carried out in the main channel and its tributaries in 28 points, registering values ​​of conductivity, pH, temperature and oxygen saturation, chemical oxygen demand, biochemical oxygen demand, total and fecal coliforms, and 413 surveys were applied to identify the Main types of activities that take place in the areas surrounding the main course and tributaries. The results showed differences in the concentrations of the different parameters in the dates and monitoring points, reporting higher concentrations of BOD5, total and fecal coliforms, the areas of the urban area. The correlation analysis showed significant relationships between the variables studied except for oxygen saturation. The analysis of variance showed significant differences between the zones for electrical conductivity, concentration of fecal and total coliforms. Surveys reveal that the majority of wastewater is deposited directly into the sewer system and the main channel of the river. It is concluded that the behavior of the different registered variables differs between the main body and tributaries, increasing the concentrations of total Coliforms, fecal from the urban area in the main body and differing the behavior of the rest of the parameters in the three zones.

WATER QUALITY INDEX OF TIGRIS RIVER WITHIN BAGHDAD CITY: A REVIEW

Tigris River is the only potable source in Baghdad city therefor many water treatment plants were built on the banks such as Al-Karkh, Sharq Dijla, Al-Sadr, Al-Wathba, Al-Karama, AlQadisia, Al-Dora, Al-Wahda, and Al-Rashed project. Tigris River suffers from the pollution that comes from various sources such as Industry, domestic sanitation, and farming activities therefore several indices were used to calculate water quality within Baghdad to convert physicochemical parameters of water to a single value that represents the river status (good, bad, very bad, etc..). The aim of this review paper to show the results of previous studies about the water quality for the Baghdad region. Most results showed that water quality was good in the north of the city of Baghdad and bad in the south of Baghdad. The deterioration of water quality was due to many reasons such as the discharge of wastewater directly into the river without pretreatment, increase in (Eclectic conductivity, Turbidity, and total suspended solids, total hardness, Iron ion, the fecal coliform) concentrations, and Climate change, therefore, Tigris River needs intensive treatment before using by humans.

Long-term water quality conditions and trends in 12 tropical coastal rivers in Northeast Brazil.

The water quality and trends in 12 tropical rivers in northeastern Brazil over a 27-year period (1990-2016; N=39,008 samples) were evaluated. The analyzed parameters included temperature, conductivity, pH, dissolved oxygen (DO), biochemical oxygen demand (BOD), nitrogen (NH4+), total phosphorus (P), and fecal coliforms. Densely populated basins (>1000 inhab km-2) presented lower DO values (average 3.4mg l-1; 43% DO saturation), while those with low demographic density (<100 inhab km-2) presented values that aligned well with the recommendations of environmental legislation (average 5.8mg l-1; 75% DO saturation). The NH4+ and P compound concentrations were typical of water bodies affected by urban inputs. The average p values were above the allowable limit (<0.1mg l-1) at all stations. The NH4+ values were high at the stations showing low DO concentrations, which suggested that due to reducing conditions after NH4+ accumulation was favored in those aquatic systems. In densely populated basins, the average fecal coliform concentrations were >40,000 MPN 100ml-1, indicating the input of improperly treated domestic/industrial liquid wastes. For the period from 1990 to 2016, 45% of the stations (N=19) showed a rate of DO reduction that ranged from 0.01 to 0.17mg l-1.O2 year-1. An increase in NH4+ concentrations was observed in 33% of the stations (N=14), with an estimated average increase rate from 0.013 to 1.8mg l-1 NH4+ year-1. These results demonstrated that the rates of increase in anthropogenic factors were significant (p<0.05), while the natural factors remained constant.

A predictive model of the impact of urbanization on bacterial loads in watersheds

Bacterial concentration is one of the most important aspects of water quality. Many regions in the world are affected by increasing urbanization and a potential increase in bacterial concentrations in waters. We used long-term data from 68 stations in eight watersheds in Eastern Thailand to quantify the temporal and geographical variation in total and fecal coliform bacteria. Descriptive statistics showed considerable seasonal, inter-annual, and geographical variation. In order to quantify this multi-level variation, we built a predictive model of bacterial loads. Using fixed- and mixed-effects regression models, we built a model including the effects of urbanization and other significant variables. The best model, fitted by restricted maximum likelihood, included the effects of season, year, urbanization as fixed effects, and of watershed and station as nested, random effects. Temporal variation was related to seasonal and annual variations. Spatial variation had a very significant impact on the bacterial concentrations. Urbanization was an important factor controlling concentrations of bacteria in rivers: we found that the proportion of urban area around a station had a statistically significant effect on log-transformed total coliform bacterial concentration with a slope equal to 1.3 (SE = 0.3), and on log-transformed fecal coliform bacterial concentration with a slope equal to 1.4 (SE = 0.3). Our model predicts that bacterial concentrations would be multiplied by 20 if land is transformed from non-urban to fully urban.

Series Type Vertical Subsurface Flow Constructed Wetlands for Dairy Farm Wastewater Treatment

Agricultural and livestock farms are the major sources of freshwater pollution in rural areas in the Philippines. Small and unregulated dairy farms operate without appropriate wastewater treatment before discharge because it is too expensive to do so. With this scenario, the emergence of the need for a sustainable and cheaper alternative for wastewater treatment gave rise to the research and development studies of the efficiency of constructed wetlands. The study aims to analyze the treatment efficiency of series type vertical subsurface flow constructed wetlands planted with Napier Grass (Pennisetum Purpureum Schumach) on University of the Philippines Los Baños (UPLB) Dairy Farm wastewater with a focus on fecal coliform concentration, electric conductivity, total dissolved solids content, nitrite and nitrate concentration and pH level. The study showed that after treatment using the vertical subsurface flow constructed wetlands, all the parameters except the fecal coliform concentration were below the standard limits set by the Department of Agriculture with average removal efficiencies of 12.94% on Electric Conductivity (EC), 12.86% on Total Dissolved Solids (TDS), 216.44% on Nitrite (NO2-N), -125.64% on Nitrate (NO3-N), and -25.64% on Fecal Coliforms (FC). With the results of the analysis, a design of series type vertical subsurface flow constructed wetland for dairy farm wastewater treatment is suggested. Doi: 10.28991/cej-2021-03091654 Full Text: PDF

Detection Of Fecal Coliforms In Water Used In Formal And Informal Food Outlets In Kasungu District, Malawi

Poor sanitary practices are common amongst many food handlers posing a health risk to consumers. Maintenance of high quality water is one of the most important aspects of ensuring consumer safety. Therefore, regular water testing is critical in public food outlets where bacterial contamination may cause outbreak of disease. The study aimed at analyzing water samples obtained from the formal and informal food outlets for the presence of fecal coliforms that are indicative of poor sanitation that result in foodborne infections amongst consumers. Using a cross-sectional design, water samples from participating food outlets (N=40) were analyzed using the membrane filtration method. Samples were filtered, under vacuum, through a cellulose acetate membrane of 0.45 μm pore size. Fecal coliforms exceeding permissible range were detected in 15 test samples (N=40). The median (IQR) concentrations of fecal coliforms (FC/100ml) in dishwashing water was 1(136) and 145(340) for the formal and informal food outlets respectively. The median (IQR) for drinking water was 0(0) with a minimum and maximum range of 0 and 14 FC/100mls. The study established a positive correlation between fecal coliforms and electrical conductivity, and total dissolved solids (p&lt;0.05) in dish washing water used at both formal and informal food outlets. Contamination was attributed to lack of running water, poor pest control and unwholesome practices in many food outlets. Based on the study findings, it is concluded that electrical conductivity, total dissolved solids and turbidity values may be used to deduce the presence of fecal coliforms in water. The study recommends that water drawn from unprotected sources must be boiled or treated at the point of use before it can be safely used in food outlets. Periodic water testing and sanitary supervisions for all food outlets must be mandatory to ensure compliance with minimum set standards.

An inverse approach to estimate bacterial loading into an estuary by using field observations and residence time

Pathogen, whose abundance is often measured by the concentration of fecal indicator bacteria, is listed as the top cause of waterbody impairments in the US. An accurate estimation of the bacterial loading from watershed is thus fundamentally important for water quality management. Despite advances in watershed modeling, accurate estimation of bacterial load is still very challenging due to large uncertainties associated with bacterial sources, accumulation, and removal in the watershed. We introduce an inverse method using field-measured bacterial concentrations and numerical model-calculated residence time to estimate the bacterial loading from the drainage basin. In this method, an estuary is divided into multiple segments. Water and bacterial fluxes between neighboring segments are computed from a set of linear equations derived based on mass balance equation and the relationship between residence time and water fluxes. Loading to each segment can then be estimated by combining the computed water fluxes and observed bacterial concentrations. The approach accounts for seasonal and interannual variations in hydrodynamics due to tide, river discharge, and estuarine circulations. The method was applied to Nassawadox Creek, a sub-estuary of Chesapeake Bay, where Fecal Coliform concentrations at 46 stations were continuously monitored. The method is verified by the high consistency between estimated loadings and presumably known input loadings in numerical experiments with either constant or time-varying input loadings. With sparse observational data, the inversely estimated loadings agree well with the loadings from a previously calibrated watershed model, demonstrating the reliability of the method. The inverse approach can be used to cross-check the result of watershed models and assess changes in watershed condition. The method is also readily applicable to other types of materials, such as inorganic nutrients.

Stormwater quality assessment and management for the town of Jasper in Alberta, Canada

Abstract Stormwater pollutants can have deleterious impacts on the aquatic life of receiving water bodies. This paper presents the findings of a stormwater quality monitoring program performed in the town of Jasper in Alberta, Canada. This is one of the very few studies done on a small urban settlement to identify key pollutants of concern, characterize stormwater and identify unique pollutant sources in the town. A total of 14 stormwater quality parameters were found to be of high concern to aquatic life. The most prominent pollutants were total suspended solids (TSS), metals and phosphorus which compared well with studies conducted in large urban settlements. Tourist influx contributed to high metal and petroleum hydrocarbon loads during the peak season due to high vehicular activity. Elk were found to reside in the town during summer and their fecal droppings resulted in elevated fecal coliform concentrations. It was found that winter road salting was responsible for excessive chloride concentrations observed during the spring melt. TSS concentrations were statistically correlated with various metals as well as phosphorus using Spearman's rank correlation. It was found that the current street sweeping schedule in the town coincided with lower TSS and metal loads in stormwater.

Neural network and cubist algorithms to predict fecal coliform content in treated wastewater by multi-soil-layering system for potential reuse.

This study aims to find the most accurate machine learning algorithms as compared to linear regression for prediction of fecal coliform (FC) concentration in the effluent of a multi-soil-layering (MSL) system and to identify the input variables affecting FC removal from domestic wastewater. The effluent quality of two different designs of the MSL system was evaluated and compared for several parameters for potential reuse in agriculture. The first system consisted of a single-stage MSL (MSL-SS), and the second system consisted of a two-stage MSL (MSL-TS). The concentration of FC in the effluent of the MSL-TS system was estimated by three machine learning algorithms: artificial neural network (ANN), Cubist, and multiple linear regression (MLR). The accuracy of the models was measured by comparing the real and predicted values. Significant (p<.001) improvements were noted for the removal of pollutants by the MSL-TS system compared with the MSL-SS system. Overall, the water quality parameters investigated complied with FAO irrigation standards. The predictive performance of the models has been compared and evaluated using several metrics. The results revealed that the ANN model yielded a superior predictive performance (R2 =.953), followed by the Cubist model (R2 =.946) and the MLR technique (R2 =.481). Based on the accurate model (ANN), the degree of influence of each predictor was investigated, and the results show that total suspended solids and pH have proved to be more useful for predicting FC concentrations.

A Multivariate and Spatiotemporal Analysis of Water Quality in Code River, Indonesia.

The efficacy of a water quality management strategy highly depends on the analysis of water quality data, which must be intensively analyzed from both spatial and temporal perspectives. This study aims to analyze spatial and temporal trends in water quality in Code River in Indonesia and correlate these with land use and land cover changes over a particular period. Water quality data consisting of 15 parameters and Landsat image data taken from 2011 to 2017 were collected and analyzed. We found that the concentrations of total dissolved solid, nitrite, nitrate, and zinc had increasing trends from upstream to downstream over time, whereas concentrations of parameter biological oxygen demand, cuprum, and fecal coliform consistently undermined water quality standards. This study also found that the proportion of natural vegetation land cover had a positive correlation with the quality of Code River's water, whereas agricultural land and built-up areas were the most sensitive to water pollution in the river. Moreover, the principal component analysis of water quality data suggested that organic matter, metals, and domestic wastewater were the most important factors for explaining the total variability of water quality in Code River. This study demonstrates the application of a GIS-based multivariate analysis to the interpretation of water quality monitoring data, which could aid watershed stakeholders in developing data-driven intervention strategies for improving the water quality in rivers and streams.

Hygienic Condition of Different Water Sources in the Kharaa River Basin, Mongolia in the Light of a Rapid Warming Trend

Mongolia is a water-scarce land-locked country, and available water resources are utilized for multiple purposes including irrigation, food preparation, drinking water for livestock and people. Limited data availability on water hygiene means that the related risks to public health are only partially understood. This is particularly problematic due to the widespread use of unimproved water sources such as surface water and water from simple shallow wells. Based on two field surveys in the Kharaa River Basin in spring 2017 and 2018, we assessed the presence and quantity of total coliforms (TC), fecal coliforms (FC), and E. coli bacteria in surface waters and wells and investigated potential linkages between temperature and hygiene. In the Kharaa River and its tributaries, TC concentrations averaged at a most probable number of (MPN) of 754 ± 761 per 100 mL and FC concentrations at an MPN of 31 ± 33. Only small and non-significant correlations between coliform concentrations and temperature were identified. Coliforms concentrations in wells were lower (average MPN for TC: 550 ± 1286, and for FC 58 ± 253). There was considerable variation between wells, with moderate but significant correlations between temperature and bacterial counts. Low water temperatures in April and May (just above freezing to less than 6.5 °C in wells and 7.5 °C to 14.5 °C in the river system) and the positive correlations between temperature and coliform concentrations particularly for well samples indicate that further warming is likely to increase the risks of microbiological water pollution. In the future, this should be complemented by modeling at a watershed scale. This should include the consideration of a trend towards stronger rainfall events, changes in livestock density, and urban sewage treatment and discharge, which are other likely drivers of changes in water hygiene.

Evaluation of a multivariate analysis modeling approach identifying sources and patterns of nonpoint fecal pollution in a mixed use watershed

Surface waters listed on impaired waters (303 d) lists due to pathogen contamination pose a significant environmental and public health burden. The need to address impairments through the Total Maximum Daily Load (TMDL) process has resulted in method developments that successfully identify nonpoint fecal pollution sources by maximizing available resources to improve water quality. However, the ability of those methods to effectively and universally identify sources of fecal pollution requires further evaluation. The objective of this research was to assess the usefulness of a previously described multivariate statistical approach to identify common patterns influencing fate and transport of fecal pollutants from sources to receiving streams using the Tuckasegee River watershed in Western North Carolina as a test watershed. Two streams were routinely monitored using a targeted sampling approach to assess fecal pollution extent and identify nonpoint sources using canonical correlation and canonical discriminant analyses. Fecal pollution in the watershed varied spatially and temporally with significantly higher fecal coliform concentrations observed in Scott Creek (f = 9.49, p = 0.002) and during the summer months (f = 14.8, p < 0.0001). Canonical correlations described 62–67% of water quality variability and indicate that fecal pollution in portions of the watershed are influenced by stormwater runoff and fecal indicator bacteria resuspension from sediment, while fecal pollution in other portions are influenced by soil erosion and surface runoff. Canonical discriminant analyses indicate that LULC significantly influences the nature and extent of fecal pollution. These results demonstrate that chemical parameters are useful predictors of fecal pollution and can help identify nonpoint fecal pollution sources in relation to land use patterns and land management practices. This approach to water quality monitoring program design and data analysis may effectively and efficiently identify parameters that best predict fecal pollution to aid in development and implementation of effective TMDLs to remediate impaired waters.