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The present study aimed to evaluate the diversity of zooplankton including rotifers and cyclops in the various freshwater ecosystems in Assiut Governorate, Egypt. Rotifers can affect the prevalence of different protozoan organisms in water, such as Cryptosporidium species. Cyclops act as intermediate host of some helminthic parasites. Microscopic analysis of the collected samples identified 3 rotifer genera and one copepod in different freshwater supplies including poultry farms, animal farms, human tanks, and fish farms. In the present study, 59 out of 136 (43.3%) water samples were contaminated with plankton. Poultry freshwater showed the highest plankton diversity and prevalence with 29 samples (21.3%), whereas the least prevalence was in human drinking water, 3 (2.2%). In the fishpond, Cyclops were observed in 3 (2.2%) of total samples. The prevalence of rotifers and Cyclops is strongly related to the summer season. Our results enrich the diversity of zooplankton in different freshwater supplies as a bioindicator of water pollution. [ABSTRACT FROM AUTHOR]

In High Mountain Asia, human-induced climate warming threatens the cryosphere. Expected long-term reductions in future runoff from glacial catchments raises concerns regarding the sustainability of these natural 'water towers' and the implications of reduced water availability for regional human and ecological systems. Ice-debris landforms (I-DL), containing ice whether moving or not include rock glaciers and ice-cored moraines, and are likely to be climatically more resilient than debris-covered and debris-free glaciers. Recent work has shown that rock glaciers contain globally valuable water supplies yet over High Mountain Asia information regarding their number, spatial distribution, morphometric characteristics and water content are scarce. Here, we present the first systematic estimate of the current extent and distribution of rock glaciers for a subset of High Mountain Asia (the Himalaya). A sample of 2070 intact and relict rock glaciers were digitized on Google Earth imagery from the Western, Central and Eastern Himalaya regions and then quantitative and qualitative characteristics were analysed regionally based on topographic data from the NASA Shuttle Radar Topography Mission (SRTM) Version 3.0 and then aggregated across the Himalaya using an "upscaling" method. The majority of the digitized landforms (∼65%) were categorised as intact rock glaciers (i.e., ice-debris Landforms, or I-DLs, containing ice) and the remainder as relict rock glaciers (i.e., discrete debris accumulations or DDAs, not containing ice). They range in elevation from 3225 to 5766 m a.s.l., with the lowest in the Central Himalaya. Sampled relict and intact rock glaciers are primarily situated on northern quadrants. Over the entire Himalaya, we identified ∼25,000 landforms, with a total estimated areal coverage of 3747 km2. The area upscaling method was validated in the Manaslu region of Nepal using high-resolution Planet data (5 m) and freely available, fine spatial resolution optical satellite data accessed through Google Earth Pro and ESRI basemaps. In absence of complete rock glacier inventories over the Himalaya, our approach proves useful to investigate the nature, distribution and infer potential future behaviour of these landforms across the Himalaya in a changing climate. • Climate change in the mountains of the Himalaya is driving glacier melting and associated changes in water supplies to downstream areas. • This impacts the water supplies for hundreds of millions of people and ecosystems and is seen as a great challenge for future sustainable development in this part of central Asia. • However, large volumes of ice are contained are contained in rock glaciers (ice-debris landforms common in high arid mountains) although research on the number and extent of these in the Himalaya is limited. • In this paper, we present the first systematic estimate of the current extent and distribution of rock glaciers for the Himalaya and show that around 25,000 landforms exist in the region, with a total estimated areal coverage of 3747 km2. • We argue that rock glaciers constitute hydrologically valuable long-term water stores and, with continued climatically-driven glacier recession and mass loss, their value is likely to become increasingly important. [ABSTRACT FROM AUTHOR]

This paper highlights the need for fire protection systems and why they should be installed, the selection of the correct system to suit the property style, layout, fire risk and also the type of system that meets the budget of the end user. The paper also outlines the requirements to install sprinkler systems throughout the UK, as they are not consistent due to the devolved administrations. [ABSTRACT FROM AUTHOR]

The societal risks of water scarcity andwater-quality impairment have received considerable attention, evidenced by recent analyses of these topics by the 2030 Water Resources Group, the United Nations and the World Economic Forum. What are the effects of fire on the predicted water scarcity and declines in water quality? Drinking water supplies for humans, the emphasis of this exploration, are derived from several land cover types, including forests, grasslands and peatlands, which are vulnerable to fire. In the last two decades, fires have affected thewater supply catchments of Denver (CO) and other southwestern US cities, and four major Australian cities including Sydney, Canberra, Adelaide and Melbourne. In the same time period, several, though not all, national, regional and global water assessments have included fire in evaluations of the risks that affect water supplies. The objective of this discussion is to explore the nexus of fire, water and society with the hope that amore explicit understanding of fire effects on water supplies will encourage the incorporation of fire into future assessments of water supplies, into the pyrogeography conceptual framework and into planning efforts directed at water resiliency. [ABSTRACT FROM AUTHOR]

The production and use of engineered nanoparticles (ENPs) inevitably leads to their release into aquatic environments, with the quantities involved expected to increase significantly in the future. Concerns therefore arise over the possibility that ENPs might pose a threat to drinking water supplies. Investigations into the vulnerability of drinking water supplies to ENPs are hampered by the absence of suitable analytical methods that are capable of detecting and quantifiying ENPs in complex aqueous matrices. Analytical data concerning the presence of ENPs in drinking water supplies is therefore scarce. The eventual fate of ENPs in the natural environment and in processes that are important for drinking water production are currently being investigated through laboratory based-experiments and modelling. Although the information obtained from these studies may not, as yet, be sufficient to allow comprehensive assessment of the complete life-cycle of ENPs, it does provide a valuable starting point for predicting the significance of ENPs to drinking water supplies. This review therefore addresses the vulnerability of drinking water supplies to ENPs. The risk of ENPs entering drinking water is discussed and predicted for drinking water produced from groundwater and from surface water. Our evaluation is based on reviewing published data concerning ENP production amounts and release patterns, the occurrence and behavior of ENPs in aquatic systems relevant for drinking water supply and ENP removability in drinking water purification processes. Quantitative predictions are made based on realistic high-input case scenarios. The results of our synthesis of current knowledge suggest that the risk probability of ENPs being present in surface water resources is generally limited, but that particular local conditions may increase the probability of raw water contamination by ENPs. Drinking water extracted from porous media aquifers are not generally considered to be prone to ENP contamination. In karstic aquifers, however, there is an increased probability that if any ENPs enter the groundwater system they will reach the extraction point of a drinking water treatment plant (DWTP). The ability to remove ENPs during water treatment depends on the specific design of the treatment process. In conventional DWTPs with no flocculation step a proportion of ENPs, if present in the raw water, may reach the final drinking water. The use of ultrafiltration techniques improves drinking water safety with respect to ENP contamination. [ABSTRACT FROM AUTHOR]

Introduction: Drinking water is the main source of fluoride exposure for the population. According to the Spanish Law RD 140/2003, the fluoride content in drinking water should not exceed the parametric value of 1.5 mg/L. Historically, certain drinking waters in the island of Tenerife have exceeded this value due to the geological/ volcanic characteristics of the Canary Islands. Fluoride (F) plays an important role in the prevention of dental caries (tooth decay). However, long exposure to concentrations above 1.5 mg/L in drinking water can cause disorders such as dental fluorosis. Objectives: To determine the amount of fluoride in the tap waters of the 11 municipalities in the north of the island of Tenerife that, at the time of the study, exceeded the parametric value for tluoride set by the Spanish legislation and to toxicologically estimate and evaluate the fluoride daily intakes from water considering the RDI (Recommended Daily Intake) established in Spain for different population groups. Method: 44 samples of tap water collected in the 11 municipalities in the study were analyzed using the fluoride potentiometric determination with an ion selective electrode. Results: 9 of the 11 municipalities presented mean fluoride concentrations in their tap water that exceeded the parametric value set by the Spanish legislation (1.5 mg/L). Considering an average daily water consumption of 2 L, the recommended daily intake (RDI) for women (3mg F/day) is exceeded in 9 of the 11 municipalities and the RDI for men (4 mg F/day) is exceeded in 5 of the 11 municipalities. Considering a daily water consumption of 1.5 L, the RDI for children of 2-3 years (0.7 mg/day) is clearly exceeded in all municipalities. Conclusions: The results show the existing public health problem on the island of Tenerife and justify the tap water consumption restrictions put in force by the Public Health Authorities of the Canary Islands at the time of the study. Children are the most exposed population group to the risks of fluoride because its RDI is lower. [ABSTRACT FROM AUTHOR]

Abstract: This paper introduces a new methodological approach of the ecological footprint explicitly addressing the sustainability of water supplies, which we call the water supply footprint (WSF). The WSF calculates the catchment area or water supply hinterland of a certain society and can serve as a strategic planning tool for local or regional water supplies linking the water demand with the water supply in a water supply footprint matrix. Based on regional water balances it estimates how much water can be appropriated for human use in an environmentally sustainable way. The proposed method is tested on the South East Queensland water supply in Australia, an area where water use restrictions are regularly imposed on the population. Applying the proposed method indicates that supply shortages may be avoided by considerably changing the organisation of water supply, thereby reducing and possibly even avoiding the necessity for large-scale supply side measures like additional sweet water reservoirs or desalination plants. In that way it is demonstrated that the WSF method is applicable at an early and strategic stage of water supply planning. [Copyright &y& Elsevier]

Cryptosporidiosis is one of the most frequent causes of diarrhea in Haiti. Transmission in children less than five years-old, HIV-infected individuals, and people living in low socio-economic conditions is frequently due to consumption of water or food contaminated by Cryptosporidium oocysts. This study examined the circulation of Cryptosporidium oocysts in surface waters and in public water supplies in the district of Port-au-Prince. Data were gathered from December 2000 to June 2002 in 37 sites. In the district of Port-au-Prince, 24/37 samples of water collected (65%) were contaminated by Cryptosporidium oocysts and 10/11 (91%) of those collected in reservoirs used by people living in peripheral areas. The rate of contamination was 7/13 (54%) in water from public standpipes provided by the public company of water distribution. All surface water (4/4) collected was highly contaminated. [ABSTRACT FROM AUTHOR]

Abstract: Groundwater is increasingly being used for public and private water supplies in Scotland, but there is growing evidence that manganese (Mn) concentrations in many groundwater supplies exceed the national drinking water limit of 0.05mgl−1. This study examines the extent and magnitude of high Mn concentrations in groundwater in Scotland and investigates the factors controlling Mn concentrations. A dataset containing 475 high quality groundwater samples was compiled using new data from Baseline Scotland supplemented with additional high quality data where available. Concentrations ranged up to 1.9mgl−1; median Mn concentration was 0.013mgl−1 with 25th and 75th percentiles 0.0014 and 0.072mgl−1 respectively. The Scottish drinking water limit (0.05mgl−1) was exceeded for 30% of samples and the WHO health guideline (0.4mgl−1) by 9%; concentrations were highest in the Carboniferous sedimentary aquifer in central Scotland, the Devonian sedimentary aquifer of Morayshire, and superficial aquifers. Further analysis using 137 samples from the Devonian aquifers indicated strong redox and pH controls (pH, Eh and dissolved oxygen accounted for 58% of variance in Mn concentrations). In addition, an independent relationship between Fe and Mn was observed, suggesting that Fe behaviour in groundwater may affect Mn solubility. Given the redox status and pH of Scottish groundwaters the most likely explanation is sorption of Mn to Fe oxides, which are released into solution when Fe is reduced. Since the occurrence of elevated Mn concentrations is widespread in groundwaters from all aquifer types, consideration should be given to monitoring Mn more widely in both public and private groundwater supplies in Scotland and by implication elsewhere. [Copyright &y& Elsevier]

Abstract: Literature harbours several reports of potable water-associated outbreaks. We studied the prevalence of Shiga toxin- (stx1/2), intimin- (eae) and haemolysin (hlyA) genes in Escherichia coli isolates from drinking water of private and public water supplies in a rural area of Upper Austria; 2633 water samples were gained between November 2000 and December 2003. Two hundred and eighty of these water samples were positive for E. coli (10.6%). Of these, 101 samples were drawn from drilled wells (36%), 96 from dug wells (34%), 61 from springs (22%) and 22 from water supplies without available information on technical details (8%); 141 of the samples were from public water supplies, 139 from private water supplies. Eleven of the E. coli isolates were found to be positive for one of the investigated virulence genes (3.9%): one isolate yielded stx2, seven eae, and three isolates had hlyA. The presence of these genes underlines the importance of control of water quality in public and also private water supplies. [Copyright &y& Elsevier]

Abstract: The correlations between ENSO (El Niño/Southern Oscillation) and crops in China have been recognized, but the research focusing on the causes behind the correlations still remains incomplete. In this study, we concentrate on the causal relationship between ENSO and rice yields in North and Northwest China. We found that there was an inconsistency in the observed correlation between rice yields and the occurrence of ENSO events during various periods from 1960 to 2004 in most provinces. Rice was vulnerable to El Niño events before 1980, while it seemed to benefit from the occurrence of such events following 1980. We established the reason for the change through a combination of mechanistic modeling and empirical statistical analysis. We concluded that much of this inconsistency in yield responses to ENSO can be attributed to the development of water supply systems throughout our study region. The meteorological impacts associated with ENSO events varied with water regime. This important finding provided a key explanation into the interaction processes between ENSO climate variability and the water supply in the rice production system, and further confirmed the importance of considering interactive effects between climate variability and human adaptation practices when assessing climate change impacts on agricultural variability. [Copyright &y& Elsevier]

The number of nosocomial infections due to Legionella pneumophila and Pseudomonas aeruginosa is probably underestimated in many countries. This article discusses the risk of legionellosis due to Legionella and P. aeruginosa for patients and hospitals staff members from the water system in different Palestinian hospitals. A total of 134 water samples were collected in 2005 from six governmental hospitals located in the West Bank. L. pneumophila serogroup 2-14 was isolated from 33 of 53 samples, and P. aeruginosa was isolated from 17 of 81 before thermal disinfection. Thermal disinfection at 80°C and progressively flushing the hot water outlets around the system was successfully efficient to eliminate Legionella and P. aeruginosa pathogens in water distribution systems. The current study is an example of how microbiological methods and site history may be used to successfully track the source of bacterial water contamination and subsequently remediate it. Thorough contaminant characterization and forensic source identification is important for designing of appropriate management strategies. [ABSTRACT FROM AUTHOR]

Using effectiveness data from a recent systematic review and cost data from programme implementers and World Health Organization (WHO) databases, we conducted a cost-effectiveness analysis to compare non-piped in source- (dug well, borehole and communal stand post) and four types of household- (chlorination, filtration, solar disinfection, flocculation/disinfection) based interventions to improve the microbial quality of water for preventing diarrhoeal disease. Results are reported for two WHO epidemiological sub-regions, Afr-E (sub-Saharan African countries with very high adult and child mortality) and Sear-D (South East Asian countries with high adult and child mortality) at 50% intervention coverage. Measured against international benchmarks, source- and household-based interventions were generally cost effective or highly cost effective even before the estimated saving in health costs that would offset the cost of implementation. Household-based chlorination was the most cost-effective where resources are limited; household filtration yields additional health gains at higher budget levels. Flocculation/disinfection was strongly dominated by all other interventions; solar disinfection was weakly dominated by chlorination. In addition to cost-effectiveness, choices among water quality interventions must be guided by local conditions, user preferences, potential for cost recovery from beneficiaries and other factors. [ABSTRACT FROM AUTHOR]

Abstract: Volcanic ash is the most widely-distributed product of explosive volcanic eruptions, and can disrupt vital infrastructure on a large scale. Previous studies of effects of ashfall on natural waters and water supplies have focused mainly on the consequences of increased levels of turbidity (ash suspended in water), acidity and fluoride, with very little attention paid to other contaminants associated with volcanic ash. The aims of this paper are twofold: firstly, to review previous studies of the effects of volcanic ashfall on water supplies and identify information gaps; and secondly, to propose a simple model for predicting effects of ashfall on water supplies using available information on ash composition. We reviewed reported impacts of historic eruptions on water supplies, drawing on case studies from New Zealand, Vanuatu, Argentina, the USA, Costa Rica, Montserrat, Iceland and Guadeloupe. Elevated concentrations of fluoride, iron, sulphate and chloride, as well as turbidity and acidity, have been reported in water supplies. From a public health perspective, the two main issues appear to be: (1) outbreaks of infectious disease caused by the inhibition of disinfection by high levels of suspended ash, and (2) elevated fluoride concentrations. We devised a simple model using volcanic ash leachate composition data to predict effects on receiving waters. Applying this model to the effects of Ruapehu ash, from the 1995/1996 eruptions, suggests that the primary effects of concern are likely to be an increase in acidity (decrease in pH), and increases in concentrations of the metals aluminium, iron and manganese. These metals are not normally considered to pose health risks, and are regulated only by secondary, non-enforceable guidelines. However, exceedences of guideline values for Al, Mn, Fe and pH will cause water to become undrinkable due to a bitter metallic taste and dark colour, and may also cause corrosion, staining and scale deposition problems in water tanks and pipes. Therefore, the main issues following volcanic ashfall of similar composition to Ruapehu ash are likely to be shortages of potable water and damage to distribution systems, rather than risks to public health. [Copyright &y& Elsevier]

In the Zenica–Doboj Canton, 1106 hepatitis A virus (HAV) infections were reported during 2000 (an incidence rate of 252/100 000 population), with 996 (90.1%) cases occurring in nine community-wide outbreaks. Analysis of water supplies showed that 398 (19.1%) samples contained coliforms, including 202 (50.8%) that were contaminated with thermotolerantEscherichia coli.Sewage sanitation systems were absent or substandard in 53 910 (81.8%) rural households. The group most affected during outbreaks comprised children aged 7–14 years (incidence rate of 598/100 000). The development of health promotion and prevention initiatives in schools, combined with rigorous hygiene measures, will be necessary to achieve control of the spread of HAV. [ABSTRACT FROM AUTHOR]