Carl Stapleton

In Europe, and in many countries around the world, there is an increasing focus on the bacterial quality of recreational bathing waters. Bathing waters are impacted by both continuous and intermittent discharges from urban and rural sources which can be a significant distance away. In order to improve the quality of bathing waters there is a need to be able to target the key sources for improvement measures. The Cloud to Coast project has collected a significant amount of data and developed models, based on the River Ribble basin in the UK, to predict time series FIO concentrations. This paper discusses the modelling of FIOs at the catchment scale and presents results from two catchments within the Ribble basin. The modelling is shown to give reasonably accurate predictions of FIO concentrations, when compared to measured data.

ABSTRACT: Details are given herein of the limitations of numerical hydroenvironmental models in predicting faecal indicator and trace metal fluxes in near-shore coastal systems. Laboratory and empirical field investigations to improve on the predictive capabilities of such models for bacteria and trace metals are outlined, including developing relationships between:(i) bacterial decay, turbidity and suspended sediment levels,(ii) adsorption and desorption kinetics for bacteria, and (iii) partitioning coefficients and salinity effects on ...

The European Union Water Framework Directive requires that Management Plans are developed for individual River Basin Districts. From the point of view of faecal indicator organisms (FIOs), there is a critical need for screening tools that can provide a rapid assessment of the likely FIO concentrations and fluxes within catchments under base- and high-flow conditions, and of the balance ('source apportionment') between agriculture- and sewage-derived sources. Accordingly, the present paper reports on: (1) the development of preliminary generic models, using water quality and land cover data from previous UK catchment studies for assessing FIO concentrations, fluxes and source apportionment within catchments during the summer bathing season; (2) the calibration of national land use data, against data previously used in the models; and (3) provisional FIO concentration and source-apportionment assessments for England and Wales. The models clearly highlighted the crucial importance of high-flow conditions for the flux of FIOs within catchments. At high flow, improved grassland (and associated livestock) was the key FIO source; FIO loadings derived from catchments with high proportions of improved grassland were shown to be as high as from urbanized catchments; and in many rural catchments, especially in NW and SW England and Wales, which are important areas of lowland livestock (especially dairy) farming, ≥ 40% of FIOs was assessed to be derived from agricultural sources. In contrast, under base-flow conditions, when there was little or no runoff from agricultural land, urban (i.e. sewerage-related) sources were assessed to dominate, and even in rural areas the majority of FIOs were attributed to urban sources. The results of the study demonstrate the potential of this type of approach, particularly in light of climate change and the likelihood of more high-flow events, in underpinning informed policy development and prioritization of investment.

In Europe, and in many countries around the world, there is an increasing focus on the bacterial quality of recreational bathing waters. Bathing waters are impacted by both continuous and intermittent discharges from urban and rural sources which can be a significant distance away. In order to improve the quality of bathing waters there is a need to be able to target the key sources for improvement measures. The Cloud to Coast project has collected a significant amount of data and developed models, based on the River Ribble basin in the UK, to predict time series FIO concentrations. This paper discusses the modelling of FIOs at the catchment scale and presents results from two catchments within the Ribble basin. The modelling is shown to give reasonably accurate predictions of FIO concentrations, when compared to measured data.

The virtual elimination of the principal point sources of human bacterial pollution through advanced treatment systems has not produced 100% compliance with microbial standards at all UK bathing water locations where they have been installed. This is partly explained by the existence of diffuse bacterial pollution derived from agricultural activities within catchments draining to the bathing zone. This pollution loading is highly episodic and driven by catchment hydrological dynamics producing a short term flush of faecal pollution early in the hydrograph event. Remediation of this diffuse pollution loading requires the type of upstream catchment management and control noted in the CEC Draft Bathing Water Directive (CEC, 2002) which suggest the implementation of Water Framework Directive (CEC, 2000) principles in the management of complex pollution sources . There is very little information on diffuse source microbial dynamics. In particular, the relative importance of different cat...

Waterborne pathogens (and associated faecal indicator organisms (FIOs)) derived from human and animal faeces are a significant water quality concern in many parts of the world. In the United States of America (USA) “pathogens” (actually FIOs: coliforms and enterococci) are the most frequent cause of “impairment” (i.e. non-compliance) in waters covered by the US Clean Water Act (see: Figure 6.1) (USEPA 2009). The design and implementation of measures to

New ‘health-evidence-based’ water quality standards for coastal waters have been proposed by WHO and incorporated in a revised EU Bathing Water Directive which comes into force in 2015 (WHO, 2003; Kay et al., 2004; Anon., 2006). The standards proposed are more stringent than the existing criteria (Anon., 1976) and are likely to reduce rates of annual compliance in UK bathing waters in the absence of any climatic drivers of environmental change (Wither et al., 2010). (A compliant water is here taken to means a bathing water that complies with the EU ‘imperative’ standard (‘sufficient’ or better after 2015). The compliance of bathing and shellfish harvesting waters is assessed using faecal indicator organisms (FIOs) (principally coliforms and enterococci bacteria) which indicate the presence of faecal matter derived from humans, livestock and wildlife. This may have associated human pathogens, if the contributing population is shedding pathogens at the time. The faecal indicator organ...

Faecal indicator organisms (FIOs) are major pollutants in many catchments world-wide, with streamside pastures on livestock farms being potentially significant sources. Hitherto, few empirical studies have quantified FIO fluxes from such areas or investigated streambank fencing (SBF) and other possible mitigation measures. The aim of this two-phase (before/after intervention) study of the effectiveness of SBF was to generate an empirical evidence-base to enable regulatory authorities to make better-informed decisions concerning the implementation of this measure. It was undertaken during the summer bathing season along a 271 m stream reach in the River Tamar catchment, SW England. The study included: cattle distribution surveys; monitoring of changes in E. coli (EC) and intestinal enterococci (IE) concentrations and fluxes down the reach and of concentrations in ditch flow and surface runoff; phage tracer studies of surface runoff from pasture land; and experimental streambed trampl...

Achieving compliance with the mandatory standards of the 1976 Bathing Water Directive (76/160/EEC) is required at all U.K. identified bathing waters. In recent years, the Fylde coast has been an area of significant investments in 'point source' control, which have not proven, in isolation, to satisfactorily achieve compliance with the mandatory, let alone the guide, levels of water quality in the Directive. The potential impact of riverine sources of pollution was first confirmed after a study in 1997. The completion of sewerage system enhancements offered the potential for the study of faecal indicator delivery from upstream sources comprising both point sources and diffuse agricultural sources. A research project to define these elements commenced in 2001. Initially, a desk study reported here, estimated the principal infrastructure contributions within the Ribble catchment. A second phase of this investigation has involved acquisition of empirical water quality and hydrol...

ABSTRACT Hydrodynamic modelling of near-shore waters has involved significant advances in recent years as rapidly expanding computer power has facilitated step change in the complexity of hydrodynamic models in terms of additional dimensions and reduced grid sizes which could not have been envisaged a decade ago. However, this model refinement has not been paralleled by advances in the representation of two core drivers of near-shore water quality models. Predicting bacterial concentrations is essential for assessment of compliance of near-shore waters with existing and proposed standards for recreational waters (EU, 2000, WHO, 1998, 2002). It is for this reason that hydrodynamic models have generally failed to provide accurate, and, therefore operationally useful, prediction of microbiological concentrations at bathing beach compliance points. This has led to unexpected, and often disappointing, results from significant infrastructure investments designed to improve bathing water quality. This study reports on two advances which have been used to drive the numerical modelling described by our co-investigators (Kashefipour et al., 2002). This approach seeks to make 'dynamic' two 'static' elements of existing modelling frameworks. The first element (addressed in this paper) is the input, or delivery, of faecal indicators into the near-shore zone from multiple sources. This is often difficult to assess because the available data are limited by: (i) sparse and imprecise microbiological enumerations in the various input streams, preventing adequate characterisation of the effects of, for example, discharge on faecal indicator delivery, (ii)sparse 'discharge' information from most sources, especially intermittent discharges from the sewerage infrastructure and (iii) a lack of knowledge on diffuse, i.e. non-sewage, sources of faecal indicator organisms e.g. from river and stream systems. Using data from a UK investigation this paper examines how these issues have been addressed to provide a dynamic, spatially referenced hourly input sequence to the near-shore models explained by our colleagues. The second aspect (addressed by our colleagues' paper) in which the existing models are 'static' is the general assumption of a uniform day time and night time decay rate for faecal indicators. This element examines the factors influencing bacterial survival and disappearance and provides the theoretical underpinning for the dynamic modelling strategy which facilitates consideration of the complex mix of bactericidal factors within the hydrodynamic modelling framework as outlined by (Kashefipour et al., 2002).

... There is a need, however, for pan-European coordination. ... are to be managed effectively through the implementation of the principles enshrined in the directive as clearly envisaged in early drafts 32 of the new Bathing Water Directive published in November 2005. 33. ...

Some 1% of the UK population derives their potable water from 140,000 private water supplies (PWSs) regulated by Local Authorities. The overwhelming majority of these are very small domestic supplies serving a single property or a small number of properties. Treatment for such supplies is rudimentary or non-existent and their microbiological quality has been shown to be poor in every published study to date. Private water supplies serving commercial enterprises such as hotels, restaurants, food production premises and factories are more frequently treated and subject to closer regulation in the United Kingdom. As a result, it has been assumed that these larger commercial supplies are less likely to experience elevated faecal indicator and pathogen concentrations at the consumer tap which have been observed at small domestic supplies. This paper reports on intensive monitoring at seven commercial private water supplies (six of which were treated) spread throughout the UK serving hote...

As the requirements of the Water Framework Directive (WFD) and the US Clean Water Act (USCWA) for the maintenance of microbiological water quality in 'protected areas' highlight, there is a growing recognition that integrated management of point and diffuse sources of microbial pollution is essential. New information on catchment microbial dynamics and, in particular, the sources of faecal indicator bacteria found in bathing and shellfish harvesting waters is a pre-requisite for the design of any 'programme of measures' at the drainage basin scale to secure and maintain compliance with existing and new health-based microbiological standards. This paper reports on a catchment-scale microbial source tracking (MST) study in the Leven Estuary drainage basin, northwest England, an area for which quantitative faecal indicator source apportionment empirical data and land use information were also collected. Since previous MST studies have been based on laboratory trials using 'manufactured' samples or analyses of spot environmental samples without the contextual microbial flux data (under high and low flow conditions) and source information, such background data are needed to evaluate the utility of MST in USCWA total maximum daily load (TMDL) assessments or WFD 'Programmes of Measures'. Thus, the operational utility of MST remains in some doubt. The results of this investigation, using genotyping of Bacteroidetes using polymerase chain reaction (PCR) and male-specific ribonucleic acid coliphage (F + RNA coliphage) using hybridisation, suggest some discrimination is possible between livestock- and human-derived faecal indicator concentrations but, in inter-grade areas, the degree to which the tracer picture reflected the land use pattern and probable faecal indicator loading were less distinct. Interestingly, the MST data was more reliable on high flow samples when much of the faecal indicator flux from catchment systems occurs. Whilst a useful supplementary tool, the MST information did not provide quantitative source apportionment for the study catchment. Thus, it could not replace detailed empirical measurement of microbial flux at key catchment outlets to underpin faecal indicator source apportionment. Therefore, the MST techniques reported herein currently may not meet the standards required to be a useful forensic tool, although continued development of the methods and further catchment scale studies could increase confidence in such methods for future application.

Under the EU Water Framework Directive (WFD) 20/60/EC and the US Federal Water Pollution Control Act 2002 management of water quality within river drainage basins has shifted from traditional point-source control to a holistic approach whereby the overall contribution of point and diffuse sources of pollutants has to be considered. Consequently, there is a requirement to undertake source-apportionment studies of pollutant fluxes within catchments. The inclusion of the Bathing Water Directive (BWD), under the list of 'protected areas' in the WFD places a requirement to control sources of faecal indicator organisms within catchments in order to achieve the objectives of both the BWD (and its revision - 2006/7/EC) and the WFD. This study was therefore initiated to quantify catchment-derived fluxes of faecal indicator compliance parameters originating from both point and diffuse sources. The Ribble drainage basin is the single UK sentinel WFD research catchment and discharges to the south of the Fylde coast, which includes a number of high profile, historically non-compliant, bathing waters. Faecal indicator concentrations (faecal coliform concentrations are reported herein) were measured at 41 riverine locations, the 15 largest wastewater treatment works (WwTWs) and 15 combined sewer overflows (CSOs) across the Ribble basin over a 44-day period during the 2002 bathing season. The sampling programme included targeting rainfall-induced high flow events and sample results were categorised as either base flow or high flow. At the riverine sites, geometric mean faecal coliform concentrations showed statistically significant elevation at high flow compared to base flow. The resultant faecal coliform flux estimates revealed that over 90% of the total organism load to the Ribble Estuary was discharged by sewage related sources during high flow events. These sewage sources were largely related to the urban areas to the south and east of the Ribble basin, with over half the load associated with the relatively small subcatchment of the River Douglas. The majority of this load was attributed to two WwTWs that discharge through a common outfall close to the tidal limit of this catchment. Budgets adjusted to accommodate the impact of proposed UV disinfection of these effluents showed that the load from these sources would be reduced significantly during base flow conditions. However, during high flow events loads would still remain high due to the operation of storm sewage overflows from stormwater retention tanks. The study identified untreated storm sewage spills from urban infrastructure and WwTW stormwater retention tanks as the dominant component of the high flow flux of faecal indicators to receiving waters of the Fylde coast and the associated bathing waters.

Investigating the distribution and origin of Cryptosporidium species in a water catchment affected by destocking and restocking of livestock as a result of a foot and mouth disease epidemic. Surface water, livestock and wildlife samples were screened for Cryptosporidium and oocysts characterised by sequencing SSU rRNA and COWP loci, and fragment analysis of ML1, ML2 and GP60 microsatellite loci. Oocyst concentrations in water samples (0-20.29 per 10 l) were related to rainfall events, amount of rainfall and topography. There was no detectable impact from catchment restocking. Cryptosporidium spp. found in water were indicative of livestock (Cryptosporidium andersoni and Cryptosporidium parvum) and wildlife (novel genotypes) sources. However, C. andersoni was not found in any animals sampled. Calf infections were age related; C. parvum was significantly more common in younger animals (<4 weeks old). Older calves shared Cryptosporidium bovis, Cryptosporidium ryanae and C. parvum. Wildlife shed C. parvum, Cryptosporidium ubiquitum, muskrat genotype II and deer genotype. Several factors affect the occurrence of Cryptosporidium within a catchment. In addition to farmed and wild animal hosts, topography and rainfall patterns are particularly important. These factors must be considered when undertaking risk-based water safety plans.

Faecal indicator organisms (FIOs) are commonly used to quantify pollution of public health significance. Health protection, as indexed by FIO control, is a central aim of new ‘catchment-scale’ water quality management required in the USA by the Clean Water Act and in the European Union (EU) by the Water Framework Directive (WFD). Experience of the former, after a decade of