News Items Archive 2014

A newly published UKWIR project report reviews the comparative benefits and disadvantages of ‘no disruption’ pipe repair methods against those of traditional repair methods.  It assesses whether the choice of repair method affects the risk of network failure in the short-, medium- and long-term.

The Drinking Water Inspectorate has issued Information Letter 04/14 updating its data reporting requirements for Cryptosporidium monitoring in drinking water supplies from 1 January 2015, with particular reference to monitoring and reporting raw water sources.

A recent paper in the Journal of Water and Health presents a review of research relevant to disinfection of bacteria with the potential to pose a severe threat to public health and safety, and their potential surrogates. The efficacy of chlorine, monochloramine, chlorine dioxide, and ultraviolet light to inactivate each organism in suspension is described. The complexities of disinfection under varying water conditions and when the organisms are associated with biofilms in distribution systems are discussed. (abstract)

Japanese workers have developed a quantitative PCR procedure for simultaneously enumerating 11 different human viral pathogens in environmental water saamples.

This Best Practice Guide on the Control of Arsenic in Drinking Water is published by IWA. It arises from the knowledge collected by the European Research Network COST Action 637 involving 27 European countries and the USA. Besides the large number of important papers, reports and reviews already available on various aspects of arsenic occurrence in environment, water and food and related human exposure, this book fills a gap in the field concerning assessment of risks, implications, challenges, and actions required by public health managers.

The July-September issue of Advances in Water Research includes an article advocating pro-active leakage management and includes links to recent Water Research Foundation and other publications relating to water loss. The article refers to a project to help the design of leakage control programmes which produced an analysis tool for leakage component analysis.

A recent article in Advances in Water Research provides a progress report on work funded by the Water Research Foundation under its Water Supply Reservoir Management Strategies project. It includes links to 2 publications already produced and one on oxygenation and circulation anticipated in late 2015. An article anticipating this latter report is also in the journal.

The recent issue of Advances in Water Research carries an article based on a Water Research Foundation project on “Optimising Treatment for the Removal of Cyanobacteria and Toxins” due for publication in 2015(article). The article makes many points including that pre-chlorination should not be used when blooms occur and also that turbidity cannot be used as a surrogate for presence of cyanobacteria.

Preparation is well under way for the proposed revision in 2020 of the WHO Guidelines. The report of meetings held in Singapore in June 2014 to progress the revision are now available. The meetings held over 2 days covered a remarkable amount of detail and the 68 page report is a mineof information. Areas considp://ered included potable re-use; alternative disinfectants; and microbial aspects.

UKWIR has published results of a study which identifies successful ways of engaging with water customers who are at risk of exceeding the standard for lead in drinking water and encouraging them to replace their lead supply pipes. It also provides estimates of the number of customers likely to replace their lead pipes assuming different interventions, and hence determines the overall effectiveness of potential lead replacement programmes.

Water stress and environmental regulations in the UK are driving UK water companies to consider reuse as a strategic supply option and so require evidence on the array of risks and opportunities this brings. This recent UKWIR publication examines evidence from over 200 relevant case studies of both successful and abandoned treated effluent reuse projects. Real (and perceived) risks associated with different reuse scenarios are identified considering their applicability in the UK.

In anticipation of a projected shortfall in water supply in the South East by 2020 Thames Water is investigating indirect potable reuse as a potential new supply option. 2,000 Thames Water customers participated in an on-line survey of their attitudes to indirect potable reuse which showed overall support for the idea of indirect potable reuse.

A recent paper in the Journal of Clinical Endocrinology and Metabolism describing a study of pregnant women with borderline thyroid function showed that exposure to high end perchlorate levels in the first trimester was associated with lower IQ in the children. Some US States already regulate perchlorate in drinking water and USEPA intends to set a standard.

A recent paper in the journal Environmental Health looked retrospectively at pregnancies in 1766 women in New England and concluded that there may be some association between TCE exposure and stillbirth, with mothers exposed to higher than the median level of TCE having a 2.38 times risk of stillbirth at 27 weeks gestation or later.

Groups in New Zealand opposed to fluoridation of drinking water have recently cited poorly designed studies based on very high fluoride levels. Results have been published of a 38 year cohort study carried out in New Zealand. After adjusting for potential confounding variables, including sex, socioeconomic status, breastfeeding, and birth weight (as well as educational attainment for adult IQ outcomes), the study showed no association between fluoride and IQ.

Workers in California have published results of a meta-analysis of published literature on distribution system deficiencies and GII. They reviewed published studies that compared direct tap water consumption to consumption of tap water re-treated at the point of use (POU) and studies of specific system deficiencies such as breach of physical or hydraulic pipe integrity and lack of disinfectant residual. Despite significant deficiencies in many studies and a publication bias in favour of studies showing positive associations they concluded that tap water consumption is associated with GII in malfunctioning distribution networks. System deficiencies such as water outages also are associated with increased GII, suggesting a potential health risk for consumers served by piped water networks.

DWI has published its latest Research Newsletter Issue 9. Completed Projects described are:-

• Assessing the likelihood of selected veterinary medicines reaching drinking water;
• Speciation of manganese in drinking water;
• Health risk reductions;
• On-line monitor performance;
• Risks from personal care products and domestic cleaning products;
• Toxicological evaluation for pharmaceuticals in drinking water;
• Raw water monitoring data;
• Viruses in raw and partially treated water;
• Enhancing the value of molecular methods to the water industry; and
• Brass fittings – a source of lead in drinking water?

Research Newsletter Issue 8

• Monitoring of Nitrogenated DBPs in drinking water;
• Understanding the changes in pesticide usage to inform water company risk assessments;
• Health-based targets for drinking water safety and regulation ;
• Probabilistic modelling for assessment of exposure via drinking water ; and
• Potential contaminants in drinking water treatment chemicals.

A review has recently been published of over 250 published and unpublished studies concerning the environmental preperties, fate, and toxicity of the four major classes of surfactant used in personal care and cleaning products. The exceptionally comprehensive review, promoted by the American Cleaning Institute, deals at length with their structures, mode of action, usage, toxicity, and biodegradability. The review concludes that the surfactants present no risk to aquatic or sediment environments but does not consider implications for drinking water abstractions.

Danish workers have published research showing that contrary to common belief, mineral coating developing in rapid sand filters improves their performance, particlarly in ammonia removal. Mineralisation is associated with increased microbial populations. This suggests that excessive back-washing can be counter-productive.

The British Geological Survey has published maps showing areas suitable for fracking and areas of major water supply aquifers in England and Wales.

In August 2015 IWA published the third edition of its widely used performance indicator system, which represents a further improvement of the original manual. It contains a reviewed and consolidated version of the indicators, resulting from the real needs of water companies worldwide that were expressed during the extensive field testing of the original system. The indicators now properly cover bulk distribution and the needs of developing countries, and all definitions have been thoroughly revised. The confidence grading scheme has been simplified and the procedure to assess the results- uncertainty has been significantly enhanced. In addition to the updated contents of the original edition, a large part of the manual is now devoted to the practical application of the system.

WRc published a DWI funded report in June 2014 on “ Risks to Drinking Water from Personal Care Products and Domestic Cleaning Products”. Of the 692 chemicals that are commonly used in PCPs and DCPs which were screened to develop a shortlist of chemicals that were identified as having a higher potential to occur in drinking water 33 were identified as of potential importance. However, ten of the 33 prioritised chemicals were predicted to produce levels of maximum exposure through drinking water and bathing close to or greater than would be anticipated through their intended use. The Report suggests targeted monitoring for these and also toxicological assessments.

UKWIR has published a review which summarises the current extent and severity of metaldehyde non-compliance in the UK and the water industry's response to it. It collates data on the costs of implementing catchment management initiatives; reviews the effectiveness of catchment management and abstraction management in limiting metaldeyde concentrations in drinking water; and highlights key evidence gaps and examples of best practice.

A European survey of regulated and emerging disinfection by-products (DBPs) in drinking waters in selected regions that were part of epidemiology studies showed that the levels of DBPs found reflected the diverse regions from which the samples were collected, the different treatment/disinfection processes and the different source waters. In addition to a wide range of concentrations of DBPs (e.g. median trihalomethanes (THMs) of 8–85 μg L–1), bromine incorporation was quite diverse (e.g. some waters were highly dominated by bromine-containing DBPs, whereas others only had chlorine-containing species). Bromine incorporation was highest in the haloacetonitriles (HANs) and was lowest in the trihalogenated haloacetic acids (THAAs). In addition, the ratios of THMs to HAAs, THMs to HANs, and THAAs to dihalogenated HAAs varied. Heauthors conclude that exposure assessment based on THMs alone was not sufficient for indicating the presence of emerging DBPs of health concern. Occurrence studies must include a more diverse group of analytes to better understand exposure to DBPs of health concern. (Abstract)

A recent AWWA publication presents 21 case studies—10 waterborne disease outbreaks, 7 cases of severe chemical contamination, and 4 close calls—written largely from the perspective of frontline personnel who experienced the events as they unfolded. An aid to learning from past failures.

Water being the universal foodstuff, this recent paper in Letters in Applied Microbiology should be of interest to anyone looking to develop novel approaches to drinking water microbiology.

A report published by the Association for Public Service Excellence (APSE), demonstrates how councils can be effective local water stewards. The report focusses on local authority planning for, and response to, extreme weather events.

Two new reports that focus on the global electricity water nexus have just been published. Three years of research show that by the year 2040 there will not be enough water in the world to quench the thirst of the world population and keep the current energy and power solutions going if we continue doing what we are doing today. Combining new research results with projections about water shortage and the world population, by 2020 many areas of the world will no longer have access to clean drinking water. The results predict that by 2020 about 30-40% of the world will have water scarcity, and according to the researchers, climate change can make this even worse.

A process for regeneration of adsorbtive medium used to remove arsenic has been developed. The regenerated medium shows no loss or degradation. The first (and only) full-scale deployment is saving the participating utility $20,000 to $30,000 per year. The savings are gained by backwashing and regenerating, rather than repurchasing, iron-based adsorptive media.

A European survey of regulated and emerging disinfection by-products (DBPs) in drinking waters in selected regions that were part of epidemiology studies showed that the levels of DBPs found reflected the diverse regions from which the samples were collected, the different treatment/disinfection processes and the different source waters. In addition to a wide range of concentrations of DBPs (e.g. median trihalomethanes (THMs) of 8–85 μg L–1), bromine incorporation was quite diverse (e.g. some waters were highly dominated by bromine-containing DBPs, whereas others only had chlorine-containing species). Bromine incorporation was highest in the haloacetonitriles (HANs) and was lowest in the trihalogenated haloacetic acids (THAAs). In addition, the ratios of THMs to HAAs, THMs to HANs, and THAAs to dihalogenated HAAs varied. Heauthors conclude that exposure assessment based on THMs alone was not sufficient for indicating the presence of emerging DBPs of health concern. Occurrence studies must include a more diverse group of analytes to better understand exposure to DBPs of health concern.

A recent paper in Advances in Water Research, the US Water Research Foundation Journal, discusses the potential for use of molecular methods in the microbiological analysis of water samples. The adoption of molecular methods is constrained by the use of culture-based methods in standards although the adoption by the EPA of a qPCR method for enterococci in recreational waters is encouraging. A combination of short duration culture followed by qPCR shows promise but needs further development. (Paper)

DWI has added a section on Private Water Supplies(PWS) to its website. The section gives advice to owners and users of PWS as well as installers and suppliers of PWS equipment. It also gives advice to Local Authorities in respect of their PWS duties.

Canadian workers showed that using 3 different PCR assays they could detect total coliforms in at least as many samples as with cultural methods. The 16S rRNA molecular assay on its own was shown to be as efficient as recommended culture-based methods. They say that the assay might be used in combination with an Escherichia coli molecular assay to assess drinking water quality. (Abstract)

WHO has released this draft report for comment by July 25th 2014. The report documents the values specified in national standards for drinking-water parameters and how they compare to those set out in the fourth edition of the WHO Guidelines for Drinking-water Quality.

WHO has recently published a reference tool to help water suppliers and regulators who are familiar with the Water Safety Plan approach, enhance their risk assessment and management and investment planning for their water distribution systems. (Full text)

Continuing work in Canada using two pilot-scale dual media (sand/anthracite) filters confirmed that the parallel biofilters performed similarly with both averaging on 21% biopolymer removal. Raw and treated water biopolymer concentrations were correlated, with increased absolute removals occurring at higher raw water concentrations. Ultrafiltration (UF) membrane fouling experiments showed substantial improvement in performance following biofiltration pretreatment by reducing hydraulically irreversible and reversible fouling rates by 14–68% and 8–55%, respectively. The results also reaffirm the importance of biopolymers at concentrations as low as ∼0.1 mg/L on irreversible and reversible UF membrane fouling and a minimal impact of humic substances. (Abstract)

Danish workers are developing a method for arsenic removal based on electrolytic iron dissolution and efficient aeration prior to sand filtration. The treatment was investigated in a pilot scale plant and full scale waterworks. The pilot scale results showed the potential for efficient arsenic removal from spiked solutions (with As in the range of 50–85 μg/L) depending on the process conditions (flow and applied current). In the waterworks where the system was implemented for a period of 14 months, there was a relationship where the higher applied current from the iron generator resulted in a better quality of water produced. The electrolytic dissolution of the Fe was found to be a practical method for iron dosing; however more work has to be done on process improvement and optimization. (Abstract)

Norwegian workers have developed a system using cultural detection of E.coli followed by molecular methods to detect host-specific markers associated with humans or animals. The method can also be used with additional marker sets to identify the presence of STEC (Shiga Toxin producing E.coli). (Paper)

UKWRIP has published a report of a workshop which mapped out current research investments in water and cities, and identified a number of opportunities to improve the UK’s approach to water and cities. The report includes a spreadsheet of over 130 current relevant initiatives. Although there is little relevant to public water supplies in the UK it is nonetheless a useful compendium.

The new Water Act received Royal Assent on May 14th 2014. The Act is wide-ranging and covers Water Supply and Sewerage licencing, and introduces a requirement to ensure resilience. It also includes sections on Water Resources, Environmental Regulation, and Flood Insurance (Water Act 2014)

A meta-analysis of 319 published studies showed that while water from improved sources is less likely to contain faecal contamination than unimproved sources, they are not consistently safe. This study also provides evidence that by equating “improved” with “safe,” the number of people with access to a safe water source has been greatly overstated, and suggests that a large number and proportion of the world's population use unsafe water (paper).

The US Water Research Foundation has published a detailed review of 1,4 dioxane and its implications for drinking water supplies.

This website has been developed by the Research Councils UK (RCUK) to enable users to search and analyse information about publicly funded research. The website shows data from all seven research councils and the Technology Strategy Board. It enables easy access to information about current research projects and outcomes of past projects and will be of interest to users such as academic institutions and the general public. The site is comprehensive,easy to use and provides access to a large number of related research projects.

The STREAM programme is delivered by five UK academic centres of excellence in water science and engineering in the UK. Coordinated by Cranfield University and including Imperial College London and the universities of Sheffield, Newcastle, and Exeter, the programme is funded by the Engineering and Physical Sciences Research Council (EPSRC) and companies who sponsor research projects. The website gives details of funded new projects available to post graduates.

Studies in many countries have demonstrated a relationship between drinking water mineral content and the risk of death in cardiovascular disease (CVD), particularly for magnesium and it has been suggested that magnesium be added to drinking water. The article evaluates the validity of this suggestion by reviewing information on possible causative agents. Major epidemiological studies on the drinking water content of calcium, magnesium, and hardness were analysed regarding exposure specificity, confounding factors, dose-response relationships and biological plausibility. Intervention experiments were analysed. The risk of death in CVD was related to the content of Ca, Mg and HCO₃⁻. The data demonstrate that Ca and Mg need to be considered together, and that HCO₃⁻ could play a role by intervening with the body acid load. There is no evidence to justify the addition of magnesium only to drinking water for preventive purposes. The data suggest that Ca and Mg could be administered together but no data are available regarding the relative proportions for an optimal effect.

The New Zealand Ministry of Health report for 2012-2103 shows that compliance with all drinking-water standards increased by 0.2 percent to 76.9 percent in population terms during 2012/13, bacterial compliance was 96.7 percent and chemical compliance was 95.3 percent. These bacterial and chemical compliance rates are also across all water supplies serving over 100 people, including small drinking-water supplies which generally experience greater difficulty in achieving compliance. However large supplies only achieved 99.0% compliance for bacterial standards and 97.1% for chemical standards. There was a slight decrease in protozoal compliance, from 79.8 to 79.2 percent. There is clearly a long way to go before drinking water in New Zealand reaches the quality enjoyed in England and Wales. (Summary)

A Water Research Foundation funded study found a set of likely causes of poor Cryptosporidium oocyst recovery in Portland Water Bureau source water from the Bull Run watershed at certain times of the year. The report presents a modification to EPA Method 1623 that improved oocyst recovery for Portland Water Bureau, and this research contributes to an improved understanding of the role that water matrices play in inhibiting oocyst recovery.

Researchers at Bristol University have shown that recovery of chlorine-injured E. coli in Colilert was not impaired within the range 33–39 °C; the equivalent range in Aquatest medium was 31–43 °C. Both these tests recovered E. coli without significant loss of performance over a wider range of temperatures than currently specified. This is important for drinking water testing where laboratory resources are limited. (Abstract)

A waterborne outbreak of cryptosporidiosis in Northamptonshire is the first waterborne outbreak shown to be due to C. cuniculus, a species previously not thought to be a human pathogen. Unusually no children under five were infected in the outbreak, which may have involved over 400 cases of which 23 were shown by laboratory testing to be microbiologically linked to C.cuniculus.

UKWIR has recently published a report (ref. 13/DW/02/67) which aims to provide water companies with an informed assessment of the current knowledge and understanding of the origin and behaviour of the organisms of potential health significance in plumbing systems.

The large number of known DBPs makes measurement impractical, if not impossible. UKWIR has just published a report (14/TX/05/2) which developes a pragmatic risk-based approach to identify potential DBPs, based on knowledge of factors which lead to their formation and mitigation. DBPs have been categorised according to their chemical structures and the potential risks for these categories, based on toxicity, likely occurrence and concentration. The approach has been encapsulated in a spreadsheet-based risk assessment tool that enables the potential formation of DBPs at treatment works to be quickly assessed, and the works to be ranked according to the risk.

Workers supported by Massachusetts Institute of Technology have demonstrated that the pores in plant xylem are capable of retaining bacteria. Passing water through intact sapwood from white pine sealed in PVC tube can remove over 99.9% of bacteria. The technique requires development but may need no external energy source and has potential for use in developing countries and for emergency supplies in the field.

For many years workers have speculated on the role of drinking water in the transmission of the Mycobacterium avium complex (MAC) with no definitive conclusions. A recent Australian PhD thesis addressing the occurrence of MAC in Brisbane's water supplies concluded that strains of MAC found in water supplies were also found in cases of disease in the community. The Author's suggestions regarding the need to boil drinking water for 4 minutes may be considered alarmist (Article)

DWI has issued an Information Letter to update companies on the outcome of the Inspectorate’s assessment of companies’ PR14 submissions for metaldehyde and to set out its position regarding the appropriateness of current legal instruments for metaldehyde and other pesticides.

A novel technique is now available which provides equal results to PCR but requires no thermal cycling and can be carried out at room temperature. The technique is known as Recombinase Polymerase Amplification (RPA) and has been successfully applied to a wide range of pathogens including cryptosporidium.

Established in March 2013 as a semi-state company under the Water Services Act 2013, Irish Water will bring the water and wastewater services of the 34 Local Authorities together under one national service provider. (Company Website)

Irish Water is gradually taking over the responsibilities from these Local Authorities on a phased basis from January 2014. It will take approximately five years for Irish Water to be fully established, at which point it will be responsible for the operation of public water services including management of national water assets, maintenance of the water system, investment and planning, managing capital projects and customer care and billing. An expert has warned that the new Company will inherit 4000 employees but will only need 1700.(Report)

Wessex Water has signed a water resilience agreement with Sembcorp Bournemouth Water to ensure that if a problem occurs on either network, a backup supply would be available to avoid any impact on customers. A small water plant will be constructed at the regional border to facilitate the bulk transfer of water.

DWI has published its annual Research Newsletter. Completed Projects described are

• Monitoring of Nitrogenated DBPs in drinking water;
• Understanding the changes in pesticide usage to inform water company risk assessments;
• Health-based targets for drinking water safety and regulation ;
• Probabilistic modelling for assessment of exposure via drinking water ; and
• Potential contaminants in drinking water treatment chemicals.

WRc has published details of the research projects in its 2014 Portfolio.

HSE has published the fourth edition of “Legionnaires' disease. The control of legionella bacteria in water systems - Approved Code of Practice and guidance”.

The book is aimed at dutyholders, including employers, those in control of premises and those with health and safety responsibilities for others, to help them comply with their legal duties in relation to legionella. These include identifying and assessing sources of risk, preparing a scheme to prevent or control risk, implementing, managing and monitoring precautions, keeping records of precautions and appointing a manager to be responsible for others.

Italian workers have shown a high level of contamination of hospital tap aerators by various species of gram-negative opportunists. A useful critique in the same journal suggests caution when interpreting the health significance of the study.(Paper, Critique)

Engineers from the A*STAR Institute of Materials Research and Engineering and colleagues at the University of Basel, Switzerland, have designed and developed a compact, portable analytical instrument that can detect multiple ions and molecules down to a level of 300 parts per billion (ppb) in less than a minute. The device is not yet commercially available. The machine, based on lab-on-a-chip technology, needs only drop-sized liquid samples. The analysis is very quick, precise and sensitive, and can be performed remotely as no direct contact with the solution is necessary. The paper reports analysis of six cations (NH₄⁺, K⁺, Ca²⁺, Na⁺, Mg²⁺, Li⁺) with a detection limit of approximately 5 μM and the analysis of the anions (Br^-, Cl^-, NO₂^-, NO₃^-, SO₄^2-, F ^-) with a detection limit of about 3 μM. The device is considered to have potential applications in the water, food and beverage, agriculture, environmental, pharmaceutical and medical industries. (Summary)

IWA has just published a review of the literature on Cryptosporidium which helps to identify the findings and formulates the key research questions. It covers these central questions:

• What are the sources/carriers of human pathogenic strains and what are the key species for a range of catchments?
• What is the contribution of pre and post weaned cattle and sheep to catchment contamination?
• What data on animal management practices (including vegetation management of riparian zones) is available?
• What are the different climatic zones across catchments and how will this impact on the survival and transmission of Cryptosporidium?

(Details)

This UKWIR report represents Stage 1 of a project to understand the potential impacts of fracking on the UK water industry. It is an 81-page document presenting an assessment of:

• The location of potential shale gas reserves in the UK;
• The relationship between shale gas reserves and water resources;
• The relationship between shale gas reserves and water company infrastructure; and
• The likely location, scale and timing of water demand

The principal benefit of the work reported here to the UK water industry is that it provides an increased knowledge and understanding of risks to water resources in terms of the likely scale, location and duration of water demand from shale gas operations ISBN1 84057 699 5 (Report)

Gateway to Research (GtR) website has been developed by the Research Councils UK (RCUK) to enable users to search and analyse information about publicly funded research. It includes data from all seven research councils and the Technology Strategy Board. The website enables easy access to information about current research projects and outcomes of past projects and will be of interest to users such as academic institutions and the general public. The site is comprehensive,easy to use and provides access to a large number of water related research projects (gateway)