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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]

Wildfires pose a risk to water supplies in the western U.S. and many other parts of the world, due to the potential for degradation of water quality. However, a lack of adequate data hinders prediction and assessment of post-wildfire impacts and recovery. The dearth of such data is related to lack of funding for monitoring extreme events and the challenge of measuring the outsized hydrologic and erosive response after wildfire. Assessment and prediction of post-wildfire surface water quality would be strengthened by the strategic monitoring of key parameters, and the selection of sampling locations based on the following criteria: (1) streamgage with pre-wildfire data; (2) ability to install equipment that can measure water quality at high temporal resolution, with a focus on storm sampling; (3) minimum of 10% drainage area burned at moderate to high severity; (4) lack of major water management; (5) high-frequency precipitation; and (6) availability of pre-wildfire water-quality data and (or) water-quality data from a comparable unburned basin. Water-quality data focused on parameters that are critical to human and (or) ecosystem health, relevant to water-treatment processes and drinking-water quality, and (or) inform the role of precipitation and discharge on flow paths and water quality are most useful. We discuss strategic post-wildfire water-quality monitoring and identify opportunities for advancing assessment and prediction. Improved estimates of the magnitude, timing, and duration of post-wildfire effects on water quality would aid the water resources community prepare for and mitigate against impacts to water supplies.

Slaughtering and sanitation activities within abattoirs in Edo State are entirely dependent on a steady supply of presumed clean water. These sources include; groundwater, surface water and precipitation. The heterotrophic, total coliform and Escherichia coli counts of sampled raw water supplies used by fifteen slaughter-houses in Benin City, Ekpoma and Auchi municipalities was determined using routine procedures which included serial dilution and multiple tube methods. Duplicate water samples were collected from each establishment once monthly for a period of two seasons (November, 2019, April to August 2020, February to March, 2021). The mean bacteriological counts were subjected to one-way ANOVA and Duncan multiple range tests at 95% probability level. Seasonal variations were analyzed using Mann Whitney test (α = 0.05). The overall mean heterotrophic bacterial and total coliform counts ranged from 9.0 × 104 ± 8746 cfu/ml to 1.7 × 105 ± 13422 cfu/ml, 1.7 × 105 ± 19957 cfu/ml and 1.7 × 105 ± 5247 cfu/ml and 83 ± 52 MPN/100 ml to 176 ± 5.2 MPN/100 ml. The variations in these mean values were statistically significant (F=9.275, F=3.664, p<0.05). Eight bacterial isolates were tentatively identified and they include; E. coli, Acinetobacter sp., Bacillus sp., Klebsiella mobilis, Micrococcus sp. Citrobacter sp., Serratia marcescens, Enterobacter sp. and Staphylococcus aureus. The detection of coliforms rendered the raw water unfit for both carcass preparation and sanitation purposes by the respective establishments. [ABSTRACT FROM AUTHOR]

Urbanization and agriculture increase the risk of water contamination in watersheds. A special concern arises when this water is used for public supply. Conventional hydrochemical methods have been applied to identify contaminants in bulk water; however, there is lack of investigation of their origins. Environmental isotopes can be used to address such knowledge gap by tracking the harmful substance back to its origins. This study evaluates the interference of urbanization as well as inorganic fertilizers in the suspended sediments of the tributaries of two impoundments, whose water supplies 72% of the municipality of Caxias do Sul, Southern Brazil. To achieve this goal, the isotopic ratios 87Sr/86Sr, 208Pb/204Pb, 206Pb/204Pb, 207Pb/204Pb, 208Pb/206Pb and 207Pb/206Pb were selected as geochemical tracers, showing promising results to evaluate sources of contamination in source water. The results of strontium isotopes showed two distinct groups, one marked by the geogenic origin of the sediment and the other by inorganic fertilizers. Lead isotopes indicated that suspended sediments have signatures compatible with the rocks that occur in the region and are in a range of isotopic ratios different from fertilizers or copper sulfate. [ABSTRACT FROM AUTHOR]

Mining and wildfires are both landscape disturbances that pose elevated and substantial hazards to water supplies and ecosystems due to increased erosion and transport of sediment, metals, and debris to downstream waters. The risk to water supplies may be amplified when these disturbances occur in the same watershed. This work describes mechanisms by which the intersection of mining and wildfire may lead to elevated metal concentrations in downstream waters: (1) conveyance of metal-rich ash and soil to surface waters, (2) increased dissolution and transport of dissolved metals due to direct contact of precipitation with mine waste, (3) increased erosion and transport of metal-rich sediment from mining waste, (4) remobilization of previously deposited metal-contaminated floodplain sediment by higher postfire flood flows, and (5) increased metal transport from underground mine workings. Predicted increases in wildfire size, frequency, and burn severity, together with the ongoing need for metal resources, indicate that improved mapping, monitoring, modeling, and mitigation techniques are needed to manage the geochemical hazard of the intersection of wildfire and mining and implications for water availability.

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]

Understanding impacts of climate change on water level fluctuations across Earth's large lakes has critical implications for commercial and recreational boating and navigation, coastal planning, and ecological function and management. A common approach to advancing this understanding is the propagation of climate change scenarios (often from global circulation models) through regional hydrological models. We find, however, that this approach does not always fully capture water supply spatiotemporal features evolving from complex relationships between hydrologic variables. Here, we present a statistical approach for projecting plausible climate-related regional water supply scenarios into localized net basin supply sequences utilizing a parametric vine copula. This approach preserves spatial and temporal correlations between hydrologic components and allows for explicit representation and manipulation of component marginal and conditional probability distributions. We demonstrate the capabilities of our new modeling framework on the Laurentian Great Lakes by coupling our copula-derived net basin supply simulations with a newly-formulated monthly lake-to-lake routing model. This coupled system projects monthly average water levels on Lake Superior, Michigan-Huron, and Erie (we omit Lake Ontario from our study due to complications associated with simulating strict regulatory controls on its outflow). We find that our new method faithfully replicates marginal and conditional probability distributions, as well as serial autocorrelation, within and among historical net basin supply sequences. We find that our new method also reproduces seasonal and interannual water level dynamics. Using readily-available climate change simulations for the Great Lakes region, we then identified two plausible, transient, water supply scenarios and propagated them through our model to understand potential impacts on future water levels. Both scenarios result in an average water level increase of

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]

Legionella species are widespread in natural water sources and man-made aqueous environments, as well as fresh-water. The present study was conducted owing to the lack of research regarding the prevalence of Legionella spp in the water sources of Ahvaz city in southwest Iran. In this study the macrophage infectivity potentiator (mip) gene sequencing was used for identification of various Legionella species isolated from different water sources. In this study, 144 water samples were collected and inoculated on the buffered charcoal-yeast extract (BCYE) agar and modified Wadowsky-Yee (MWY) medium. The DNA was extracted from positive cultures. The Legionella species were confirmed by amplifying a 654 bp fragment of the 16S rRNA gene. The mip gene of all isolates were amplified by PCR and purified for sequencing. The mip gene sequences were analyzed by jPHYDIT software version 1. The results showed a 13.9% (20/144) prevalence of Legionella spp. in water sources of Ahvaz city, southwest Iran. Analyzing of the mip gene sequences showed, out of 20 Legionella isolates, 13 isolates (54.1%) were positive for L. pneumophila, 5 isolates (20.8%) were positive for L. worsleinsis, one isolates for each one of L. dumoffi and L. fairfieldensis, (4.1%). According to our research, the occurrence of Legionella spp in water sources could be a hazard for the health systems especially in the hospitals. The regular monitoring of these water sources by health planners may therefore be useful for decreasing the risk for Legionella spp. infections.

Groundwater depletion has been a consequential problem in Kansas, a drought-prone state widely reliant on the High Plains aquifer. This manuscript explores well ownership's moderating effects on the relationships between awareness of water supplies and the use of water-saving devices. It assesses one of the only quantitative datasets of private water well owners used in social scientific research (n = 864) and discusses the intricate results of multi-group structural equation models with respondents organized by their water supplies. Well ownership and water literacy are significantly correlated to owning water-conservation technologies, and well ownership combined with access to municipal water weakens the correlations between awareness and owning water-saving appliances. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to assess drinking water quality at 12th Khoroo of Sukhbaatar District of Ulaanbaatar, Mongolia. Methods: Water samples were collected at four different locations and water sources included a borehole well, plastic containers from two different households and from the drinking water faucet of the Family Health Center. Samples were analyzed for complete physicochemical characterization. Results were compared to the National Standard (MNS 0900:2018), WHO and EPA guideline values. Results: Indicators of drinking water quality were within the national and international guideline values in collected water samples except for aluminum (maximum measured value 1.5 mg/l, WHO guideline value 0.2 mg/l) and iron (maximum measured value 13.9 mg/l, WHO guideline value 0.3 mg/l). In addition, some diversity in concentrations was observed depending on water sources. Conclusion: Overall, samples for majority of physical and chemical parameters lie within guideline limits as set by WHO except for aluminum and iron. Thus, more research is needed to cover a larger area of the city with full physicochemical and microbiological characterization.

The act of ensuring freshwater is considered the most essential and basic need for humanity. Although the planet is water-rich in some terms, the freshwater sources available for human consumption and beneficial uses are very limited. Excess population growth, industrial development coupled with improving living standards have caused an unprecedented need for freshwater all over the world. Regions once rich in water resources are struggling to meet the ever increasing demands in recent years. In addition, climate change and unsustainable management practices have led to a situation called 'drought' in many regions. Water supplies in drought conditions can be addressed by taking two major approaches related to management and technology development. The management approaches include demand mitigation and supply enhancement. Demand mitigation can be done by implementing water conservation practices, and by enforcing a mechanism to influence user-responsible behavior through higher water fares and other billing routes. Supply enhancement can be achieved by utilizing the methods available for water reclamation, reuse and recycle including rain harvesting. This paper provides a critical insight of the causes for drought and the issues caused by persistent drought conditions followed by discussion of management and technological approaches required to maintain adequate water resources around the world. Challenges and opportunities involved in implementation of desalination and water reuse technologies in addressing global water scarcity are discussed in detail with case studies [ABSTRACT FROM AUTHOR]

The water sector is going through a paradigm shift. Many communities are incorporating decentralized solutions such as water reuse and recycling, stormwater capture, and demand-side management in order to address both short-term and long-term water resources challenges due to population increase, economic growth, intensified climate variability, as well as environmental concerns. For these projects to be sustainable, local characteristics including social and institutional contexts must be incorporated in the planning process. This paper presents a flexible and bottom-up framework that facilitates integration of such characteristics in evaluation of various water resource management strategies. It incorporates various locally-driven factors such as water use efficiency, stress on existing supplies, and adaptation capacity potential, to identify how various local and regional solutions affect resiliency at the utility and regional levels. Rather than defining top-down resilience standards, this framework incorporates quantitative and qualitative assessments that can help decision-makers tailor adaptation measures to the needs and opportunities of a given location or community. A case study application of the framework in the San Francisco Bay Area highlights how community-level characteristics can be used to identify opportunities and adaptation strategies in order to enhance both local and collective water resource resiliency. [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]

There is growing concern that a warming climate will alter water supplies in many regions. Determining the best course of management and adaptation is an important task for water managers. This study explores the impact of climate warming and differing treeplanting scenarios on water supplies (peak flow rates, times, and total water yield) in four forested mountain watersheds in Colorado, USA. Tree migration, disturbance, active management (treeplanting), and a changing climate were simulated with a spatially explicit, high-resolution hydrologic model. Disturbance and climate had considerable impacts: relative to current conditions, forest mortality increased water yield, primarily due to lower transpiration losses; peak flows occurred earlier (1-2 weeks); and winter baseflow rates were higher (2-5 times current rates). Planting had minimal effects on peak flow rates/timing and total water yield in some watersheds, but more in others. Simpler topography and low biodiversity were associated with higher sensitivities to vegetation/management choices: depending on the scenario, models predicted a -22 to +12% difference in peak flow rates coupled with a +10 to +117% range in total yield (between scenarios). Overall, certain systems are more sensitive to management than others, and we discuss ways to evaluate potential hydrologic sensitivity to disturbance and management in mountainous watersheds. [ABSTRACT FROM AUTHOR]

The presence of Vibrio cholerae non-O1 in water supplies for human consumption in the city of Campeche and rural locality of Bécal was investigated. V. cholerae non-O1 was detected in 5.9% of the samples obtained in deep pools of Campeche. Studies conducted in Bécal and neighbourhood of Morelos in Campeche indicated that collected samples harbored V. cholerae non-O1 in 31.5% and 8.7% respectively. There was a particular pattern of distribution of V. cholerae non-O1 serotypes among different studied regions. Accordingly, V. cholerae non-O1 serotype O14 predominated in the deep pools of Campeche and together with V. cholerae non-O1, O155 were preferentially founds in samples taken from intradomiciliary faucets in the neighbourhood of Morelos. Samples from Bécal predominantly presented the serotype O112. 60% and 53.8% of all studied strains of V. cholerae non-O1 proved to be resistant to ampicillin and carbenicillin. 3.1%, 7.7% and 6.2% presented resistant to doxycycline, trimethoprim-sulfamethoxazole and erythromycin respectively. The study showed the necessity of performing a strong epidemiologic surveillance for emergence and distribution of V. cholerae non-O1

This article measures irrigated agricultural outcomes under the prior appropriation doctrine by developing a model of farmers’ land allocations in response to water supply change. The modelling approach considers the institutional factors of water rights and permits the inclusive determination of water and land allocations. We utilize farm-level data of irrigated agriculture in Water District #1 in Idaho to examine the predictions from our theoretical model. The water rights priority date is consolidated at the farm level and used to differentiate farmers’ responses. We test a set of hypotheses that relate to water supply and crop revenue. Our results suggest that the water rights priority has a profound impact on agricultural outcomes, indicating strong institutional effects and weak influence of market-based approaches. Farmers respond to both long-term and seasonal water supply change and variation, and they respond to seasonal water supply forecasts in varied ways depending on their water rights portfolios, thus signalling a disproportionate distribution of potential impacts of water supply change. [ABSTRACT FROM PUBLISHER]

Summary: Background: Stenotrophomonas maltophilia causes opportunistic infections and remains a problem pathogen on intensive care unit (ICU) due to its multidrug resistance. Aim: An outbreak of S. maltophilia on ICU is described in order to highlight the risk from contaminated devices for supply of drinking water. Methods: The outbreak was investigated by a combination of epidemiology, environmental sampling and molecular typing. Findings: From 2009 to 2011 isolates of S. maltophilia from 23 patients were found to belong to only two genotypes by contrast with isolates from 52 other patients during this period, which represented distinct strains. The monthly incidence for all S. maltophilia strains ranged from 0 to 11% and for the two outbreak strains from 0 to 9%. Admission and weekly pharyngeal screening on ICU showed that the outbreak strains were acquired on ICU (range: 3–90 days). The majority of isolates (74%) were from the respiratory tract. Only two of 12 (17%) colonized intubated patients developed pneumonia. Environmental sampling found the two outbreak strains in two sinks and in the drinking water of the cooling unit in the ICU kitchen. S. maltophilia had formed a biofilm in the flexible tube from the carbon filter to the chiller and from the latter to the tap at the kitchen sink. This cooled water was used for providing drinking water and mouth care to ICU patients. The outbreak strains disappeared after removal of the water-cooler and the monthly incidence fell to <2% of ICU admissions. Conclusion: This outbreak report highlights the risk from biofilms in devices that supply drinking water for ICU patients. [Copyright &y& Elsevier]

Cha et al. (Water Resources Management, 26(18):4183-4201 ) improved the method used to measure the vulnerability of a reservoir water supply that arises due to water scarcity in a dry season. Water supply vulnerability is expected to increase due to climate change. The authors showed that the Gwangdong Reservoir Drought Management Model (GRDM2), developed in a previous study and based on the adaptation mechanism, is useful to estimate the vulnerability of water supplies. The authors assumed 48 future scenarios, consisting of a combination of 6 future inflow scenarios and 8 future water requirement scenarios, of the Gwangdong reservoir drought management system. They computed damage cost of water scarcity in dry seasons until the 2050s. Simulation results showed that severe damage may take place from the 2020s and damage four times greater than in the 2009 water scarcity event may occur in the 2050s. As a result, GRDM2 was reported to be useful to measure the magnitude of climate change vulnerability, concentrating on damage of water scarcity in a dry season. [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]

As part of a regional screening to evaluate the risk, for the health of populations, to certain classes of emerging substances, several families of pharmaceuticals and hormones were looked for in waters intended to drinking. Thus, 52 substances were investigated in 71 surface waters and 70 groundwaters. Results indicate that no water was free of pollutants, regardless of its origin (surface or groundwater) and the season of collect. The pharmaceuticals most frequently detected and with the highest concentration levels were salicylic acid, carbamazepine and acetaminophen. Among hormones, testosterone, androstenedione and progesterone were detected in almost all the samples. Globally the groundwaters were less contaminated than surface waters in regards pharmaceuticals frequencies and levels. On the other side, androgens and progestagens were present with comparable frequencies and levels in both compartments. The risk linked to the presence of these substances on human health is discussed. [Copyright &y& Elsevier]

Physical modelling experiments have been carried out in a cold room to test on a small scale, the effects of water supply during the thaw of an experimental slope with permafrost. Permafrost was maintained at depth and a thin active layer was frozen and thawed from the surface. Data from the experiments relate to two different conditions, first with moderate rainfall, and second with heavy rainfall during the thaw period. When moderate rainfall is applied during thaw phases, the experimental slope is slightly degraded. At the scale of the experiment, erosion processes involve frost jacking of the coarse blocks, frost creep and gelifluction that induce slow and gradual down slope displacements of the active layer, but also small landslides leading to large but slow mass movements with short displacements. Changes in experimental slope morphology are marked by the initiation of a small-scale drainage network and the development of a little crest line which shows a progressive upslope migration. With such boundary conditions, there is not enough water supply to evacuate downslope the whole of the eroded material and a topographic smoothing is observed. When heavy rainfall is applied during thaw periods, rapid mass wasting (small mud-flows and debris flows) become prominent. Slope failures are largely controlled by the water saturation of the active layer and by the occurrence of steeper slopes. At the scale of the experiment, rates of erosion and maximum incision increase by about 100% leading to significant slope degradation with marked and specific scars comparable to gullying. These morphological changes are dependant on both the size and the frequency of catastrophic events. These experiments provide detailed data that could improve the knowledge of the physical parameters that control the initiation, at a small-scale, of erosion processes on periglacial slopes with a thin active layer and/or with thin cover of mobilizable slope deposits. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This article reports a quantitative microbial risk assessment of the risk of Giardia and Cryptosporidium in very small private water supplies. Both pathogens have been implicated in causing outbreaks of waterborne disease associated with such supplies, though the risk of endemic disease is not known. For exposure assessments, we used existing data to derive regression equations describing the relationships between the concentration of these pathogens and Escherichia coli in private water supplies. Pathogen concentrations were then estimated using national surveillance data of E. coli in private water supplies in England and France. The estimated risk of infection was very high with the median annual risk being of the order of 25-28% for Cryptosporidium and 0.4% to 0.7% for Giardia, though, in the poorer quality supplies the risk could be much higher. These risks are substantially greater than for public water supplies and well above the risk considered tolerable. The observation that observed infection rates are generally much lower may indicate increased immunity in people regularly consuming water from private supplies. However, this increased immunity is presumed to derive from increased disease risk in young children, the group most at risk from severe disease. [ABSTRACT FROM AUTHOR]

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]