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This review examines the aims of and approaches to the Quantitative Microbial Risk Assessment (QMRA) of untreated recreational waters. The literature search was conducted on four databases and yielded 54 papers, which were analyzed on a quantitative (time-trend, geographical distribution, water type) and qualitative (aims, source of microbial data, pathogens and their measurement or estimation, ways to address variability and uncertainty, sensitivity analysis) basis. In addition, the parameters, implications, and limitations were discussed for each QMRA step. Since 2003, the number of papers has greatly increased, highlighting the importance of QMRA for the risk management of recreational waters. Nevertheless, QMRA still exhibits critical issues, above all regarding contamination data and dose-response relationships. To our knowledge, this is the first review to give a wide panoramic view on QMRA in relation to recreational exposure to untreated waters. This could be useful in identifying the current knowledge gaps and research needs.

Microbiological examination of water sample is usually undertaken to ensure that the water is safe to drink and bath in. Many potential pathogens could be associated with the water. In this juncture it is very important to protect and conserve the surface and ground water from the microbial contamination. The successful microbial pollution abatement depends not only on treatment and control but also on efficient monitoring of drinking and bathing water resources. For this, research approaches are very important for providing potable and safe drinking and bathing water to the humanity.

Coastal environments have experienced a rapid transformation due to the expansion of tourism. This growth may enhance problems as over-saturation of spaces or environmental pollution. One of the main problems is associated with the collapse of environmental infrastructures, which may become saturated during high seasons. Indeed, wastewater treatment plants (WWTP) can be located in coastal areas delivering high concentrations of nutrient effluents into the marine environment. Alternatively, WWTP effluents are introduced into coastal aquifers via injection wells, given that the geological matrix is used to filter naturally the transported effluent solutes. However, the injection of significant amounts of WWTP effluents can modify the hydrogeological dynamics and enrich substantially the solute concentrations in groundwaters. Zones with a hydraulic connection between the coastal aquifer and the sea, these contaminated groundwaters may be transferred to coastal environments via Submarine Groundwater Discharge (SGD). Thus, SGD may act as a pathway delivering part of the WWTP-derived nutrients and pollutants into the marine environment, which may lead to eutrophication or harmful algal blooms. More importantly, such process may become threatening for society when the discharge occurs into bathing waters, affecting the ecosystem and perception of stakeholders.In this study, we evaluate the role of SGD as a conveyor of nutrients from a karstic coastal aquifer affected by the injection of WWTP effluents to the Deià cove in Mallorca (Balearic Islands). Results show that the tourism seasonality changes the coastal aquifer natural dynamics during the dry season, delivering via SGD, nutrients concentrations above the maximum limits established by the Spanish and European water framework directives. Due to those enriched nutrient fluxes, the coastal water ecosystem has registered the highest values of ∂15N in Posidonia oceanica in the Balearic Islands and suffers periodic algal blooms, creating a conflict among stakeholders.

The safety of beachgoers and swimmers is determined by the presence or absence of microbial contaminants and cyanobacterial toxins in the water. This study compared the assessment of bathing waters according to the Bathing Water Directive, which is based on the concentration of fecal contaminants, with some modifications, and a new method based on the concentration of chlorophyll-a, which corresponds to the World Health Organization (WHO) guidelines used for determining cyanobacterial density in the water posing threat to people health. The results obtained from the method based on chlorophyll-a concentration clearly showed that the number of bathing waters in Poland with sufficient and insufficient quality were higher in 2018 and 2019, compared to the method based on microbial contamination. The closing of bathing waters based only on the visual confirmation of cyanobacterial blooms might not be enough to prevent the threat to swimmers’ health. The multivariate analyses applied in this study seem to confirm that chlorophyll-a concentration with associated cyanobacterial density might serve as an additional parameter for assessing the quality of bathing waters, and in the case of small water reservoirs, might indirectly inform about the conditions and changes in water ecosystems.

Supplementary data to this article can be found online at https://doi.org/10.1016/j.scitotenv.2020.140237. Thirty people (mostly children) experienced an episode of skin rash days after a sand sifting beach operation at Porto Pim Beach in Faial, Azores during June 2019. An environmental and epidemiologic investigation was conducted to identify the cause of the outbreak of skin rash. The epidemiologic investigation found that some of the patients experiencing symptoms had never entered the beach water. During the pollution period and throughout the epidemiologic investigation, faecal indicator bacteria levels (94 CFU/100 ml for intestinal enterococci and 61 CFU/100 ml for Escherichia coli) in water remained under the limits used for the ninety-five percentile calculation of an Excellent coastal and transitional bathing water defined in the Portuguese Legislation (100 CFU/100 ml for intestinal enterococci and 250 CFU/100 ml for Escherichia coli). Thus sand contact was considered as a likely primary exposure route. Sand microbiological analysis for faecal indicator organisms and electron microscopy strongly suggested faecal contamination. Chemical analysis of the sand also revealed a concomitant substance compatible with sodium-hypochlorite as analysed using gas chromatography and subsequently confirmed by free chlorine analysis. Inspection of the toilet facilities and sewage disposal system revealed a leaking sewage distribution box. Collectively, results suggest that the cause of the outbreak was the leaking underground sewage distribution box that serviced the beach toilet facilities (40 m from beach), where sodium-hypochlorite was used for cleaning and disinfection. This sewage then contaminated the surficial sands to which beach goers were exposed. Chlorine being an irritant substance, was believed to have been the cause of the symptoms given the sudden presentation and dissipation of skin rashes. No gastro-intestinal illness was reported during this episode and during the following 30 days. Like water, beach sand should also be monitored for safety, especially for areas serviced by aged infrastructure. Highlights: An episode of skin rash was experience by 30 people at a beach; Analysis of the sand revealed a substance compatible with NaOCl concomitant high levels of faecal indicator organisms; Sodium-hypochlorite was used for cleaning and disinfection of toilet facilities; A leakage in the sewage system was found to have been the cause of the outbreak. Financial support from CESAM (UID/AMB/50017-POCI-01-0145-FEDER-007638), via FCT/MCTES, from national funds (PIDDAC), cofounded by FEDER, (PT2020 Partnership Agreement and Compete 2020). info:eu-repo/semantics/publishedVersion

The Systems Approach Framework with an integrated Ecological-Social-Economic assessment was applied to address the issue of zebra mussel (Dreissena polymorpha) farming in the large Oder (Szczecin) Lagoon, southern Baltic Sea. Heavy eutrophication hampers the use of the lagoon and zebra mussel farming is considered as new use and potential measure to improve water quality. Three alternative scenarios were developed in interaction with local stakeholders: 1) the production of mussels as fresh feed and meal on a commercial basis seemed not profitable, because of a limited market for fresh mussels (zoos, aquaculture) and low prices for organic feed. 2) Mussel cultivation to improve transparency and attractiveness of bathing waters near beaches had only a limited potential (0.2 m improvement of Secchi depth). A higher mussel biomass would increase the risk of temporary hypoxia. 3) Mussels farms for improving the environmental status (according to EU Water Framework Directive) by supporting macrophyte restoration were considered as the most promising scenario. Our model simulations suggested that as soon as a compensation for nutrient removal is considered, all mussel farm scenarios could cover the costs. Experiments and literature confirm that the conditions for an environmental friendly farming approach in the lagoon are suitable. Steps towards and problems associated with an implementation, e.g. invasion of Dreissena bugensis (quagga mussel), are discussed. Each step of the Ecological-Social-Economic assessment and major lessons learnt are documented in detail. Altogether, the approach turned out to be very suitable for this issue.

Profiling bathing waters supported by Quantitative Microbial Risk Assessment (QMRA) is key to the WHO's recommendations for the 2020/2021 revision of the European Bathing Water Directive. We developed an area-specific QMRA model on four pathogens, using fecal indicator concentrations (E. coli, enterococci) for calculating pathogen loads. The predominance of illness was found to be attributable to Human Adenovirus, followed by Salmonella, Vibrio, and Norovirus. Overall, the cumulative illness risk showed a median of around 1 case/10000 exposures. The risk estimates were strongly influenced by the indicators that were used, suggesting the need for a more detailed investigation of the different sources of fecal contamination. Area-specific threshold values for fecal indicators were estimated on a risk-basis by modelling the cumulative risk against E. coli and enterococci concentrations. To improve bathing waters assessment, we suggest considering source apportionment, locally estimating of pathogen/indicator ratios, and calculating site-specific indicators thresholds based on risk assessment.

致病微生物可以通过饮用水、食物或直接接触感染人群和动物。随着我国经济的高速发展和人民生活水平的提高、旅游度假经济的迅速发展，滨海浴场水质越来越受到人们的关注。海水浴场环境中的微生物污染对旅游者身体健康甚至生命安全有直接影响，越来越受到人们的重视。因此，了解、掌握和有效管理水环境中的微生物污染是相关行业和管理机构所面临的重大挑战之一。随着计算机和数值模拟技术的迅速发展，计算机模型技术正越来越多地被国内外国学者、工程咨询机构和环境管理部门应用于微生物污染的研究及制定相关政策的过程中。然而，我国关于海水浴场微生物污染预测模型的相关研究工作和发达国家相比相对滞后。本文对预测和管理海水浴场污染的有效工具数学模型的研究进展及应用进行研究和总结。 Human and animals may be infected by pathogens in water and food consumption and direct body contact with contaminated waters. With the rapid development of economy and tourism industry and growth in the living standard, bathing water quality in China is getting more attention. The marine tourism industry is the new growth point of economic development in China. Microorganism contamination of coastal bathing water sites is a major threat to swimmers; therefore, coastal bathing water quality is getting more and more attention. The ability to predict fate and transport of faecal bacteria in bathing waters is quite challenging to water managers and government authorities. In recent years, the developments of computing technology and numerical modeling technique have provided valuable tools for water scientists, consulting companies and water management authorities to apply water quality models to bathing waters. However, advances of research on prediction model for micro-organism contamination in China is relatively slow compare to developed countries. Here in this study, the recent advances of physical-based faecal bacteria fate and transport model were studied.

Pollution of surface waters with pathogens from combined sewer overflows limits recreational use of surface waters. Large retention basins are a satisfactory solution but they are rarely sufficient for economic or space reasons. Fast disinfection during the overflow is an alternative, but few methods are known and each has problems. This work evaluated for the first time the full-scale disinfection using performic acid by the removal of the two currently regulated indicator bacteria for bathing water quality, Escherichia coli and Enterococcus . Experiments were performed at a sewage bypass through a sea-outfall pipe with a minimum hydraulic retention time of 24 min. The disinfection efficiency in the field was measured by analyzing samples taken before and after the treatment. Samples were also treated with performic acid in the laboratory to measure the disinfection effectiveness and kinetic of degradation of performic acid. Doses of 1–8 ppm of performic acid achieved 1.0–3.5 log removal of E. coli and 1.0–2.44 log removal of Enterococcus in the field, but were somewhat higher in laboratory conditions at 1.69–4.38 and 1.0–4.27 log units, respectively. Studies of the degradation of performic acid in collected real samples showed more than 50% was degraded in 20 min, and mostly degraded by 120 min. Comparison of field and laboratory dosed samples detected that performic acid synthesis did not start in one event and clogging of the sampler in another event. Overall the tests showed that the treatment was successful but it is indicated that online control could benefit treatments efficiency.

An exploratory study is presented to investigate human activities pollution in the coastal waters of a popular tourist destination in the west coast of Tangier, Morocco. A series of bathing water samples were examined for arsenic (As), iron (Fe) and phosphorus (P) concentrations in the western coastal waters of Tangier. Additionally, quasi-simultaneous satellite images from Sentinels-2 and 3 were processed to retrieve water leaving reflectances in the same locations. The bathing water samples showed high concentrations of As, P and Fe in the Boukhalef River mouth and in two nearby beaches; Jbila and Sidikacem, which appeared closely correlated with Sentinel-3 reflectances at bands 6 (560 nm) and 7 (620 nm). Since algorithms for Chlorophyll-a and Total Suspended Matter Concentrations rely on these wavelengths, they too were found to be closely related to high As, Fe and P concentrations. Therefore, caution must be taken when analysing these level-2 products in close proximity to the Boukhalef River mouth, since results may be biased due to the presence of significant As, Fe and P concentrations. In this case, Sentinel data proved to be a potentially useful tool with prospects to be used for monitoring environmental hazardous substances such as metals (e.g. As and Fe) spatial distributions in the west coast of Tangier, Morocco.

In recent years, there has been growing concern about the impact of diffuse source pollution on water bodies, particularly due to associated health risks. Coastal waters can receive considerable inputs of pollutants from catchments since they serve as sinks for many diffuse pollutants. Furthermore, bathing waters have in the recent past often failed to comply with the various standards set by different bathing water directives. The Severn estuary has recently attracted a lot of attention in terms of bathing water compliance due to its potential to generate a considerable amount of renewable energy for the UK. It is against this background that a physical model of the estuary has been set up in the Hydraulics Laboratory at Cardiff University, for studies to be undertaken to mimic the conditions of the prototype. A sandbox filled with non-cohesive sediments within the laboratory has been set up to investigate the behaviour of pollutants in propagating from the idealised groundwater environment into the estuarine waters. It has been demonstrated that for a semi-diurnal tidal estuary like the Severn, tides have a lesser effect on the transport of solutes than flows from the catchments. Thus the impact of pollution from diffuse sources to marine environments from catchments could be higher in less tidally dominated coastal waters than a tidal one.

The approval of the current Bathing Water Directive (Directive 2006/7/EC) set the necessity to define the bathing water profile. The goals established in the definition of the profile are: (i) to know the processes that determine the concentration of bacteriological indicators in the aquatic environment, (ii) to obtain relationships between the cause of pollution and its effects, and (iii) to evaluate the fulfilment of the Directive and to set the Quality Monitoring and Assessment Program, according to the bacteriological characteristics of the bathing water. In this paper an approach to elaborate the bathing water profile and its application to several bathing waters located in Santander municipality (North Spain) is shown. The methodology involves the assessment of advection, diffusion and reaction processes of bacteriological organisms in the aquatic environment by using mathematical models and the selection of an indicator to evaluate the probability to exceed the bacteriological concentrations established in Directive 2006/7/EC, which is useful for the ‘source apportionment’ assessment. In the definition of the bathing water profile we have considered the sanitation system operating under normal conditions, which includes storm water overflows, uncontrolled discharges and the discharge produced when the pumping system of the wastewater breaks. Finally, according to the bacteriological characteristics of the bathing water it is necessary to develop the Quality Monitoring and Assessment, which has been done taking into account the requirements established in Directive 2006/7/EC and the uncertainties detected in such a method regarding the number of samples to be considered.

The passage makes an analysis about water utilization structure by consulting literature and questionnaire survey. Household water consumption rose steadily and its proportion in domestic water rose from 39.8% in 1999 to 66.8% in 2008, and the flushing and bathing accounted for the largest amount of household water, its proportions is 27.1% and 26.4%. The bathing water of the southern city was wasted; it produces water-using potential. So the prevalence rate of the advanced instruments is important for using water efficiently.

Contamination of public water ways with sewage represents a serious environmental and health risk. We monitored pollution of the river Thames by enumerating the indicator organism Escherichia coli. Samples were taken from a site in central London near Waterloo Bridge in different seasons. E. coli were quantified using a membrane filtration method, and correlated with the tidal variations of the river and meteorological data on rainfall and temperature. More frequent and severe incidents of pollution occurred in the autumn. Heavy rainfall resulted in sharp peaks of E. coli contamination that implies a potential increase of numbers of pathogenic micro-organisms. Sixty percent of all samples were found to be in excess of the accepted upper limit of pollution set by European Union (EU) legislation for bathing water. This study demonstrated that frequent sewage pollution of the Thames results in high numbers of E. coli and incidents of detectable levels of pathogenic bacteria demonstrating the need for regular monitoring of bacterial pollution.

The Scottish Environment Protection Agency (SEPA) has developed, and runs, real-time bathing water quality predictions at ten sites throughout Scotland since 2004. Daily bathing water quality predictions are posted on electronic variable message signs at 10 beach locations networked to a central communication centre and updates are simultaneously made on the SEPA website, phone and text message service. Antecedent rainfall and subsequent river flow can significantly increase the concentrations of faecal indicator organisms in bathing waters. The SEPA signage prediction tool, an Excel spreadsheet based model, was developed and used to set site-specific criteria for rainfall and river flow to predict bathing water quality based on historical data. Real-time predictions against the current EU Bathing Water Directive were correct or precautionary on 99% of days and correct for 82% of compliance samples during 2007, and 81% of compliance samples during the 2008 season. The revised 2006 Directive sets out more stringent bathing water quality standards which require increased model performance. New predictive models are now being trailed using decision tree statistical software and are intended to replace the existing prediction tool by 2012.

This volume offers a detailed overview of currently applied and tested wastewater treatment technologies and the integration of advanced processes to remove trace organic contaminants and microorganisms. It discusses the potential of enhanced biological treatment to produce effluent suitable for reuse, new processes for urban wastewater disinfection and the reduction of antibiotic resistant bacteria, as well as the effect of advanced oxidation processes on wastewater microbiome and chemical contaminants. It also presents membrane bioreactors, moving bed bioreactors, light and solar driven technologies, ozonation and immobilised heterogeneous photocatalysis and provides an evaluation of the potential of constructed wetlands integrated with advanced oxidation technologies to produce wastewater safe for reuse. Furthermore, the volume discusses water reuse issues and standards, the status of membrane bioreactors applications, and the treatment of reverse osmosis concentrate for enhanced water recovery during wastewater treatment. Finally, it presents recent developments in potable water reuse and addresses various important issues in this framework, like the proper protection of public health, reliability and monitoring. This volume is of interest to experts, scientists and practitioners from various fields of research, including analytical and environmental chemistry, toxicology and environmental and sanitary engineering, as well as treatment plant operators and policymakers. This volume offers a detailed overview of currently applied and tested wastewater treatment technologies and the integration of advanced processes to remove trace organic contaminants and microorganisms. It discusses the potential of enhanced biological treatment to produce effluent suitable for reuse, new processes for urban wastewater disinfection and the reduction of antibiotic resistant bacteria, as well as the effect of advanced oxidation processes on wastewater microbiome and chemical contaminants. It also presents membrane bioreactors, moving bed bioreactors, light and solar driven technologies, ozonation and immobilised heterogeneous photocatalysis and provides an evaluation of the potential of constructed wetlands integrated with advanced oxidation technologies to produce wastewater safe for reuse. Furthermore, the volume discusses water reuse issues and standards, the status of membrane bioreactors applications, and the treatment of reverse osmosis concentrate for enhanced water recovery during wastewater treatment. Finally, it presents recent developments in potable water reuse and addresses various important issues in this framework, like the proper protection of public health, reliability and monitoring. This volume is of interest to experts, scientists and practitioners from various fields of research, including analytical and environmental chemistry, toxicology and environmental and sanitary engineering, as well as treatment plant operators and policymakers.

Trihalomethanes (THM) are by-products of disinfection of bathing waters with chlorine. They are formed by reaction of chlorine and/or bromine with the organic matter present in the water. THM represent a major problem in public swimming pools in Slovenia as according to the data of National monitoring program THM levels in public swimming pools in Slovenia in years 2005–2011 exceeded the legally permitted limits in 15 % to 80 % of samples. In the countries where level of THM in the bathing waters is not regulated by national legislation, the situation could be much worse. The THM concentrations in Slovenian swimming pools are not high; although each exceeded THM value is harmful to human health. When an adequate quantity of water in public swimming pools is exchanged on regular basis, the levels of THM are usually not exceeded but when the quantity of exchanged water is not adequate or technology of bathing water preparation is not appropriate, THM values usually exceed legally permitted limits. Today’s state of the art of bathing water preparation techniques allows the efficient preparation of bathing water without resulting in increased levels of THM.

The Working Group and associated workshop series were funded by the Natural Environment Research Council as part of the Delivering Healthy Water project (NE/I022191/1). LF received funding in part by the European Regional Development Fund Programme and the European Social Fund Convergence Programme for Cornwall and the Isles of Scilly The use of molecular tools, principally qPCR, versus traditional culture-based methods for quantifying microbial parameters (e.g., Fecal Indicator Organisms) in bathing waters generates considerable ongoing debate at the science–policy interface. Advances in science have allowed the development and application of molecular biological methods for rapid (~2 h) quantification of microbial pollution in bathing and recreational waters. In contrast, culture-based methods can take between 18 and 96 h for sample processing. Thus, molecular tools offer an opportunity to provide a more meaningful statement of microbial risk to water-users by providing near-real-time information enabling potentially more informed decision-making with regard to water-based activities. However, complementary studies concerning the potential costs and benefits of adopting rapid methods as a regulatory tool are in short supply. We report on findings from an international Working Group that examined the breadth of social impacts, challenges, and research opportunities associated with the application of molecular tools to bathing water regulations. Publisher PDF

Due to the increasing economic and cultural value of bathing waters and the shellfish industry in the UK and worldwide, water quality in estuarine and coastal waters has attracted considerable public attention in recent years. To obtain accurate predictions of the concentration distributions of faecal indicator organisms (FIOs) in coastal waters for better management of bathing water compliance, it is necessary to build an integrated modelling system to predict the complete diffuse and point source inputs from river and catchment basins. In the present paper, details are given of the development of such an integrated modelling system for simulating the transport and decay processes of FIOs, from catchment areas upstream from the coastal region, in which a distributed catchment module, a 1D river network module and a 2D estuarine and coastal module are linked dynamically by boundary inputs and outputs. Extensive measured data from the catchments, river networks and estuaries have been collated to determine the model parameters. Verification results of the distribution of water levels, flows and velocities, and suspended sediment and Escherichia coli concentrations, at controlled monitoring sites are presented, which show that the integrated model predictions generally agree well with the measurements, although locally appreciable errors can occur. The model results also highlight the importance of including the flux of FIOs via sediments being an important factor in terms of assessing the quality of bathing waters. The main factors influencing the relatively high concentration values in the bathing region are analysed, based on the model predictions and measured data, with four categories of FIO concentration levels being reviewed.

An assessment of the impact of the new microbial water quality standards of the proposed EU Bathing Water Directive on the classification of designated Irish coastal bathing areas is presented. The new standards are applied retrospectively to the microbial water quality results for the bathing seasons of 1999, 2000 and 2001, and the outcome is compared with that recorded under the present Bathing Water Directive. A Microsoft EXCEL application was developed to generate the retrospective bathing area classifications according to the proposed Directive (Excellent, Good, Poor). It was found that the number of Irish coastal bathing areas not attaining ‘Excellent’ classification (as would be required at present for the Blue Flag award) was trebled; the number attaining ‘Good’ classification was increased by about 50%, and the number attracting ‘Poor’ classification (equivalent to ‘Fail’ under the present Directive) was increased nine-fold. Some of the shortcomings of the proposed Directive and suggestions for its revision are discussed.

The quality of coastal recreational waters is monitored in Europe and other geographical areas through the analysis of faecal indicator bacteria, i.e. total and faecal coliforms and more recently E. coli and intestinal enterococci as in the new EU Bathing Water Directive (2006/7/EC). The old and new indicators and their methods of analysis are presented in this chapter underlying the limitations detected for the methods included in the new Directive. The expertise achieved along the ca. 25 years of monitoring the Catalan bathing waters revealed the two factors responsible of sporadically altering the otherwise excellent water quality of our beaches. These factors are rain events and incidences of the sewerage system. The Catalan beaches have been classified on the basis of the impact that rain events may have on altering their water quality. This information is now used to provide almost real-time warnings through the recently launched mobile app. Common alteration of the water aspect such as water discolouration, phytoplankton blooms and presence of foam that may be perceived as contamination by the public showed after investigation to correspond mainly to natural phenomena. The interrelationship established with the municipalities and the developed communication systems enabled to obtain accurate timely information from each bathing area.

The ability of Morecambe’s three designated bathing waters to pass the EU Directive on Bathing Water Quality depends on the time of day when the sample is taken, the indicator organism tested for and whether the test uses the most strict (Guideline) or the least strict (Imperative) criteria. Morning and afternoon sampling for faecal coliforms, faecal streptococci and the pathogenCampylobacter was carried out monthly over the 1996 and 1997 bathing seasons. In the afternoons average faecal coliforms declined by 77% in 1996 and 87% in 1997 compared with the mornings, faecal streptococci by 79% and 83% and campylobacters by 66% and 86%. This decline in bacterial numbers between morning and afternoon was related to variations in water temperature and levels of ultraviolet radiation. All three bathing waters failed the Guideline criteria of the EU Directive on Bathing Water Quality. Using the Imperative criteria, no bathing waters passed in the mornings of either year, some passed in the afternoons of 1996 and all passed in the afternoons of 1997. The increased pass rate in 1997 coincided with improved sewage treatment, high temperatures and increased levels of sunshine. In 1997 sampling by the Environment Agency produced fewer failures than our morning sampling but more than our afternoon sampling. Their sampling was done around midday. It is suggested that where possible all sampling of EU designated bathing waters should be carried out in the early morning.

Human health can be adversely affected through lack of access to drinking water, inadequate sanitation, consumption of contaminated freshwater and seafood, and exposure to contaminated bathing water. For example, bioaccumulation of persistent organic contaminants may raise health concerns in vulnerable population groups. The wide range of “contaminants of emerging concern” present in European waters is a growing environmental and human concern. These substances are used in pharmaceuticals, personal care, and other consumer products, and their adverse effects have only recently become apparent. Understanding of their sources, emissions, levels, and effects in the aquatic environment is also limited. In this chapter, we review the advanced technologies recently investigated for the successful elimination of such contaminants present in urban municipal wastewater treatment plant effluents. An overview on the microcontaminants’ behavior throughout conventional and advanced biological systems is also presented, stressing the important buffer effect of their adsorption on supported biofilm. It has been also stressed that combination of membrane filtration technologies and biological treatment avoids secondary clarification and tertiary steps. The use of membranes for wastewater treatment has rapidly increased in the last years due to the exceptional high-quality standards typically for reusing purposes given. Finally, advanced chemical and biological oxidation technologies must be efficient not only in removing microcontaminants but also pathogens and microorganisms from treated water for reusing applications. For instance, the elimination of antibiotics which may lead to proliferation of antibiotic resistance in pathogenic or nonpathogenic microorganisms must be a target jointly with contaminants of emerging concern removal from treated water.

In Denmark the hygienic quality of the bathing water has been controlled, based on general guidelines since 1978. Today more than 1100 control sites in marine areas have been established to ensure safe bathing water quality. According to EEC directives and Danish tradition, the control is usually performed by measuring the content of the indicator bacteria Escherichia coli (E. coli) in 5 to 20 test samples each bathing season.In Denmark, control programmes and data are evaluated using basic statistical quality control principles. This paper presents general guidelines for bacterial control, their statistical background and practical application. Furthermore, the evaluation and application of a specific programme for control of Staphylococcus aureus (S. aureus) are presented. This programme was used in a Danish bay where the authorities prescribe direct control of these potentially harmful bacteria.

Enterolert (IDEXX Laboratories Inc., Westbrook, Maine), a semiautomated, most probable number method for enumeration of enterococci, was compared with the standard membrane filter method by parallel testing of 138 marine and freshwater recreational bathing water samples. No statistically significant difference and a strong linear correlation were found between methods. Culturing of 501 Enterolert test wells resulted in false-positive and false-negative rates of 5.1 and 0.4%, respectively. Less time for setup, incubation (24 versus 48 h), and reading of Enterolert permits more efficient monitoring of recreational bathing areas.

Presents a collection of slides covering the following topics: Yorkshire water area; water environment; water leakage problem; improved leakage detection; network data; bathing water directive; water pollution; energy optimisation; high quality data components; data validity; data accuracy; data reliability; data completeness; and data timeliness.

UV-irradiation as an effective method of diminishing germs in the outlet of wastewater treatment plants was studied in a half-scale pilot-project sponsored by the State of Bavaria/BRD for a period of 3 years. Technical, physical and biological parameters capable of influencing this process were examined. The possibility to improve the hygienic and also the ecological structure of receiving waters was put to discussion. Possible effects of formed bypproducts upon the water biocoenosis of rivers were pointed out. The results demonstrated that UV-irradiation can diminish the number of germs in the outlet of a treatment plant to an extent which is sufficient to guarantee the maintenance of the bacteriological and presumably also the virological values set by the EC Bathing Water Directive. Nevertheless the UV-treatment process requires further technological development and research work concerning i.e. the improvement of hydraulic conditions, coat-forming on the quartz sleeves of the lamps, photochemical forming of by-products, after-growth and effects upon the localised benthic flora and fauna of the receiving water. It has to be stressed that a significant improvement of the bacteriological structure of flowing waters is only attainable, if the influx from non-point sources can be reduced simultaneously.

Design proposals for a pure oxygen based treatment system based on BOC's VITOX process are described for Anglian Water's Southend-on-Sea sewage treatment works which will be required to be uprated from primary to secondary treatment under the requirements of the E.C. Urban Wastewater Treatment Directive. There are very tight space constraints on site. The requirements of the E.C. Bathing Water Directive have to be met too and a potential ozone disinfection system is described. Results of large-scale trials are presented.

The evidence for the link presumed to exist between feecal contamination of recreational waters and the diseases suffered by users of such waters is reassessed. For minor diseases the causes of the symptoms are not clearly established and it is concluded that more research is needed before preventative measures can be realistically devised.

Mass populations of toxic cyanobacteria in recreational waters can present a serious risk to human health. Intelligence on the abundance and distribution of cyanobacteria is therefore needed to aid risk assessment and management activities. In this paper, we use data from the Compact Airborne Spectrographic Imager-2 (CASI-2) to monitor seasonal change in the concentration of chlorophyll a (Chl a) and the cyanobacterial biomarker pigment C-phycocyanin (C-PC) in a series of shallow lakes in the U.K. The World Health Organization guidance levels for cyanobacteria in recreational waters were subsequently used to build a decision tree classification model for cyanobacterial risk assessment which was driven using Chl a and C-PC products derived from the CASI-2 data. The results demonstrate that remote sensing can be used to acquire intelligence on the distribution and abundance of cyanobacteria in inland waterbodies. It is argued the use of remote sensing reconnaissance, in conjunction with in situ based monitoring approaches, would greatly aid the assessment of cyanobacterial risks in inland waters and improve our ability to protect human health.

This paper presents a preliminary study of the water profile with reference to microbiological parameters, required by Directive 2006/07/EC (European Community 2006) concerning the management of bathing water quality, in the coastal belt of the Province of Venice (Italy, Northern Adriatic Sea). A historical database has been implemented with monitoring data for the period 2000-2006 (data on rivers, bathing and marine coastal waters and on the characterization of Wastewater Treatment Plant (WWTP) discharges) from the institutional activity of Veneto Regional Environmental Prevention and Protection Agency (ARPAV). An integrated areal analysis for the microbiological investigation of homogeneous stretches along the coast of the Province of Venice was performed for a preliminary characterization of the bathing water profile considering water quality status and existing pressure sources.ARPAV is the institutional body responsible for environmental monitoring and control activities. Data were produced from monitoring and controls made available by the Regional Environmental Informative System and extracted and elaborated for the period of interest (2000-2006). Sampling and analysis of microbiological parameters were executed following the official Italian methods in accordance with international procedures (APHA et al. 1998). For the purpose of this study, the coast was divided into eight stretches, which were considered to be homogeneous according to their physical and geographical characteristics. An ANOVA statistical assessment has been performed on stretches I, V and VIII.From the integrated areal analysis of microbiological parameters in the homogeneous stretches along the coast of all the investigated matrices, high mean levels of faecal contamination were found in some cases. The most critical situation amongst the stretches evaluated is to be found in stretch VIII-Ca' Roman, Sottomarina and Isola Verde shores (Southern part of the Province). These results can be widely attributed to pressure sources from the Brenta and Adige rivers, rather than to local contributions. Stretches VI and VII, which correspond to the area from Punta Sabbioni (Cavallino shore N-E) to the Pellestrina shore (S-W), present the best conditions for faecal contamination parameters (low pollution levels). These situations can probably be explained given that WWTPs 7 and 8 have two submarine outfalls at a distance of about 4 km from the coastline and therefore a discharge point which is distant from the bathing and marine coastal monitoring stations; there are also no river mouths in these two stretches. Due to lack of data, it was not possible to implement seasonal assessments.This study aimed to develop an integrated areal analysis for biological parameters along the coast over the period 2000-2006 for the identified homogeneous stretches in order to develop a preliminary approach for the characterization of the water profile, as requested by directive 2006/7/EC. From the integrated analysis of the stretches, it is evident that in some cases there are high levels of faecal contamination along the coast which can be caused by river flows which heavily condition the quality of coastal waters as verified with the statistical assessment.From the preliminary analysis, the submarine outfalls seem to be the best solution to guarantee good bathing water quality on the coast. Nevertheless, it must be observed that this solution cannot overlook the possible impact of the discharges on seawaters intended for a specific use, such as mussel farms with reference to coastal hydrodynamics. Therefore, a sound wastewater dispersion analysis on the discharges of the WWTPs for the identification of the interested area and the level of contamination must be performed; a modelling study on pollution dispersion is complementary to this study (Scroccaro et al. 2009). This analysis highlights the critical stretches as being numbers II and, above all, VIII with particular correlation with the main river mouths. Thus, it is evident that the issue of microbiological impact must be studied following a river basin approach according to the influence of river loads on coastal areas.

The Urban Wastewater Treatment Directive (UWWTD) requires EC member states to take action to limit pollution from storm overflows and to improve unsatisfactory intermittent wet weather discharges from combined Sewer Overflows (CSOs) and stormtanks at wastewater treatment plants. While there are no specific European requirements, such wet weather intermittent discharges can also contribute to failures to meet standards set by other Directives, such as the Fishery, Bathing Water and Shellfish Waters Directives.

This report focuses on the studies o f the bathing water microbiological quality in Latvian coastal zone of the Baltic sea and the Gulf of Riga in May-October, 1998-1999. The microbiological studies has been done in the different coastal zones of Kurzeme and Vidzeme, downstreams o f small rivers and biggest rivers Venta and Gauja, discharges o f wastewater treatment plants and the public bathing waters in Ventspils and Saulkrasti municipality area to assess their quality according to the EU Blue Flag and Latvian National Standard criteria. The microbiological examinations were carried out in accordance with the International Standard Methods. A complex of indicatororganisms - total and thermotholerant coliforms (E.coli), streptococci, and heterotrophicplate count (37°,21°C) has been tested. Water quality in the Kurzeme has been found much better on the beaches of the Baltic sea than the most urbanised beaches of Gulf o f Riga. The quality o f the Ventspils public bathing waters has been evaluated as very good (80-100% o f data). Whereas as a result of anthropogenic load only 61-82% o f data conforms the obligatory requirements of the bathing water quality in Saulkrasti coastal zone. In the study the microbiological pollution, sources and levels of their dynamics and hydrological factors are interpreted. The colour maps o f the bathing waters quality are presented.

The applicability of WHO/UNEP criteria and the EC bathing water directive as microbial water quality guidelines were examined by means of an epidemiological-microbiological study of two Mediterranean bathing beaches. Neither set of guidelines proved particularly successful for protecting the public from health hazards related to faecal contamination of bathing waters.

There is a measurable risk of acute gastroenteritis associated with swimming in marine waters contaminated with human fecal wastes to levels that would be aesthetically acceptable. The enterococcus level in the bathing water is the best single measure of its quality relative to the risk of swimming-associated, pollution-related infectious disease. Three mathematically expressable indicator-illness relationships (criteria) are available from which recreational water quality guidelines can be extrapolated from the criteria once a decision has been made as to the acceptable risk of illness. The recently revised USEPA recreational water quality criteria and guidelines reflect this regulatory approach. A model is presented for the regulation of water quality which defines decision-making and actions by federal and local agencies as well as resource users. This model requires the ability to predict illness rates from monitoring data. Three equations, each corresponding to one of the criteria, are available for doing so. Concept and supporting epidemiological data indicate that the criteria do not apply to situations in which the sources of contamination are the fecal wastes from small numbers of individuals (e.g. boat wastes, the bathers themselves) or from lower animals (e.g. stormwater run-off). Differential die-off of viral pathogens and the bacterial indicator during wastewater chlorination and protracted residence in marine waters may also confound the use of the criteria in specific situations.

The current proposal for a revised European Directive concerning the quality of bathing water significantly increases the demands for the control of wet-weather discharges. A densely urbanised combined catchment was modelled for a 19-year long rainfall series in order to assess the current situation and to evaluate the benefits of potential solutions. Storage and advanced physical-chemical treatment of stormwater in the STP may significantly contribute for the reduction of the overflow volumes but reductions of the spill frequency under 2.5 spill days per bathing season are hardly obtained. This study reveals the severe strains that the local rainfall pattern may place on the control of the frequency of wet-weather discharges, pointing to serious technical, social and economical implications, at the local and at the national level, if the current proposal for a revised European Directive on Bathing Water is enforced.

The relatively frequent observation, during periods of onshore drift, of a surface line of convergence in nearshore coastal waters may have significant implications for the sampling procedure used for monitoring compliance with the EC Bathing Water Directive. A simple theory is developed for predicting the formation of the convergence line, and a possible alternative sampling method is suggested.