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In 2017, a comprehensive review of groundwater resources in Jordan was carried out for the first time since 1995. The change in groundwater levels between 1995 and 2017 was found to be dramatic: large declines have been recorded all over the country, reaching more than 100 m in some areas. The most affected areas are those with large-scale groundwater-irrigated agriculture, but areas that are only used for public water supply are also affected. The decrease of groundwater levels and saturated thickness poses a growing threat for drinking water supply and the demand has to be met from increasingly deeper and more remote sources, causing higher costs for drilling and extraction. Groundwater-level contour lines show that groundwater flow direction has completely reversed in some parts of the main aquifer. Consequently, previously established conceptual models, such as the concept of 12 “groundwater basins” often used in Jordan should be revised or replaced. Additionally, hydraulic conditions are changing from confined to unconfined; this is most likely a major driver for geogenic pollution with heavy metals through leakage from the overlying bituminous aquitard. Three exemplary case studies are presented to illustrate and discuss the main causes for the decline of the water tables (agriculture and population growth) and to show how the results of this assessment can be used on a regional scale.

Copper is an essential trace element, the imbalances of which are associated with various pathological conditions, including cancer, albeit via largely undefined molecular and cellular mechanisms. Here we provide evidence that levels of bioavailable copper modulate tumor growth. Chronic exposure to elevated levels of copper in drinking water, corresponding to the maximum allowed in public water supplies, stimulated proliferation of cancer cells and de novo pancreatic tumor growth in mice. Conversely, reducing systemic copper levels with a chelating drug, clinically used to treat copper disorders, impaired both. Under such copper limitation, tumors displayed decreased activity of the copper-binding mitochondrial enzyme cytochrome c oxidase and reduced ATP levels, despite enhanced glycolysis, which was not accompanied by increased invasiveness of tumors. The antiproliferative effect of copper chelation was enhanced when combined with inhibitors of glycolysis. Interestingly, larger tumors contained less copper than smaller tumors and exhibited comparatively lower activity of cytochrome c oxidase and increased glucose uptake. These results establish copper as a tumor promoter and reveal that varying levels of copper serves to regulate oxidative phosphorylation in rapidly proliferating cancer cells inside solid tumors. Thus, activation of glycolysis in tumors may in part reflect insufficient copper bioavailability in the tumor microenvironment.

Background: Groundwater supplies for drinking water are frequently contaminated with low levels of human enteric virus genomes, yet evidence for waterborne disease transmission is lacking. Objectives: We related quantitative polymerase chain reaction (qPCR)—measured enteric viruses in the tap water of 14 Wisconsin communities supplied by nondisinfected groundwater to acute gastrointestinal illness (AGI) incidence. Methods: AGI incidence was estimated from health diaries completed weekly by households within each study community during four 12-week periods. Water samples were collected monthly from five to eight households per community. Viruses were measured by qPCR, and infectivity assessed by cell culture. AGI incidence was related to virus measures using Poisson regression with random effects. Results: Communities and time periods with the highest virus measures had correspondingly high AGI incidence. This association was particularly strong for norovirus genogroup I (NoV-GI) and between adult AGI and enteroviruses when echovirus serotypes predominated. At mean concentrations of 1 and 0.8 genomic copies/L of NoV-GI and enteroviruses, respectively, the AGI incidence rate ratios (i.e., relative risk) increased by 30%. Adenoviruses were common, but tap-water concentrations were low and not positively associated with AGI. The estimated fraction of AGI attributable to tap-water—borne viruses was between 6% and 22%, depending on the virus exposure—AGI incidence model selected, and could have been as high as 63% among children < 5 years of age during the period when NoV-GI was abundant in drinking water. Conclusions: The majority of groundwater-source public water systems in the United States produce water without disinfection, and our findings suggest that populations served by such systems may be exposed to waterborne viruses and consequent health risks.

Sustainable Development Goal 6 aims to achieve universal access to water and sanitation services by 2030; this is expected to cost an estimated US$150 billion per year. Where will this funding come from? One possibility is private finance in the form of direct equity investment from private water companies and lending from commercial banks. Evidence suggests, however, that private investments in water and sanitation have not materialised as planned due to the sector’s risk – return profile. Water and sanitation are considered 'too risky' by private investors and returns insufficiently rewarding. One alternative that may help to fill the water supply and sanitation (WSS) funding gap is an as yet untapped source of public finance: public banks. There are over 900 public banks in the world, with US$49 trillion in assets; they have, however, been largely underestimated as an important source of water and sanitation funding and have also been neglected by academic research and by mainstream policy organisations such as the World Bank. There is a need to better understand how public banks can be mobilised as effective funders of public water. In this article we provide a brief history of public banking practices in the water sector, review their pros and cons, and discuss the significance of the emergence of a new type of public water operator and the potential these entities offer for financing in this sector.

Groundwater is an integral part of water resources. Groundwater has a vital role in water use in Kabul, Afghanistan. Nowadays, it is the only available source for water supply in Kabul city. The study aimed to comprehensively review the spatiotemporal groundwater distribution, physicochemical and bacteriological specifications of groundwater, and its consumption in Kabul, Afghanistan. Based on developed specific search terms to locate appropriate literature, the cited material is evaluated for relevance and reliability. Due to several causes, the mean annual decrease in groundwater levels between 2008 and 2016 is 1.7 m. About 33% of supply wells are not in operation due to declining groundwater tables. According to most reports, the physicochemical and bacteriological contents of groundwater in Kabul city exceeds World Health Organization (WHO) and National Drinking Water Quality Standard (NDWQS) limits. Individuals use water through four significant suppliers: Private wells, private suppliers, public water supply, and public wells. The study provides further insight into groundwater's current condition, and some recommendations are also presented to improve the sustainable development of groundwater.

Legionella , the causative agent of Legionnaires’ disease, is an emerging concern for water utilities. Passaic Valley Water Commission (PVWC) is a public drinking water supplier, which provides treated surface water to approximately 800,000 customers in New Jersey. To evaluate the occurrence of Legionella in the PVWC distribution system, swab, first draw, and flushed cold water samples were collected from total coliform sites ( n  = 58) during a summer and winter sampling event. Endpoint PCR detection methods were combined with culture for Legionella detection. Among 58 total coliform sites during the summer, 17.2% (10/58) of first draw samples were positive for 16S and mip Legionella DNA markers and 15.5% (9/58) in flushed samples. Across both summer and winter sampling, a total of four out of 58 sites had low-level culture detection of Legionella spp. (0.5–1.6 CFU/mL) among first draw samples. Only one site had both a first and flush draw detection (8.5 CFU/mL and 1.1 CFU/mL) for an estimated culture detection frequency of 0% in the summer and 1.7% in the winter among flushed draw samples. No L. pneumophila was detected by culture. Legionella DNA detection was significantly greater in the summer than in the winter, and detection was greater in samples collected from areas treated with phosphate. No statistical difference was found between first draw and flush sample detection. Total organic carbon, copper, and nitrate were significantly associated with Legionella DNA detection.

Increasingly frequent Harmful Algal Blooms (HABs) are generating growing public concern and attracting new policy focus both across the United States and globally. One particularly acute problem with HABs is the potential impact on drinking water safety due to high levels of microcystin toxins in the public water supply. We study households’ averting expenditure in response to a HAB outbreak in the Toledo, Ohio water supply. Using household level data from the NielsenIQ consumer panel for bottled water purchases, we estimate both post-matching difference-in-difference models and household fixed effect models of averting behavior. Our estimates provide the first revealed preference estimates of averting expenditure associated with drinking water contamination by HABs. We find that household averting behavior in response to a 3-day water advisory persists beyond the transitory event period with a declining magnitude over time. Per household averting expenditure is approximately $3.60, providing a lower bound willingness to pay to avoid HABs in public drinking water supplies. Our results imply a total averting expenditure of $792,950 across all affected households serviced by the Toledo public water supply.

Groundwater contamination by nitrate is a common problem in many parts of the world. The agriculturally important Shimabara district in Nagasaki, Japan, is experiencing this problem. The general source of drinking water of the study area is groundwater and consequently the nitrate contamination is a significant problem. For this reason, a groundwater investigation was performed and water samples were collected at 40 locations including residential areas, public water supply wells, springs, and rivers from August 2011 to November 2013. Results showed that nitrate nitrogen (NO 3 -N) concentration is exceeding the Japanese drinking water quality standards (10 mg L −1 ) at 15 locations. Maximum NO 3 -N concentration was 26.6 mg L −1 . Nitrate ( NO 3 - ) was strongly correlated with Cl − ( r  = 0.96), K + ( r  = 0.68), SO 4 2 - ( r  = 0.66), and Ca 2+ ( r  = 0.59), respectively. The high correlations with Cl − and K + are related to livestock waste. Corresponding correlation with SO 4 2 - is related to chemical fertilizers and Ca 2+ to calcareous material to neutralize acidic soil. Both the first and second components in principal component analysis reflect ion dissolution from aquifer matrix during groundwater flow along the mountain side towards the lower reaches of the alluvial fan. Using hierarchical cluster analysis, chemical characteristics of groundwater were classified into four clusters. One cluster is strongly related to the nitrate contaminated groundwater and the other clusters reflect the origin of the major ions in the groundwater.

Coastal zones are crucial ecosystems supporting significant biodiversity and pertinent socio-economic activities. However, anthropogenic development contributes to socio-environmental complexities, particularly public water supply threats caused by climate change. This research presents a case study on the north-western coast of Yucatan, Mexico, which models potential saltwater intrusion in groundwater for multiple projections of sea level rise and recharge change due to climate change and its implications for the public water supply of the regional population and ecosystem. For this purpose, a previously calibrated and validated numerical model is employed, adapting its boundary conditions, keeping its calibrated hydrogeologic parameters, and considering the 2040 and 2100 climate change projections. Simulation results show that under these projections, significant saltwater intrusion may occur, reducing freshwater thickness due to increased salinity in groundwater and a loss of freshwater sources resulting from brackish-saline wedge intrusion. These scenarios are of particular concern as freshwater in this coastal region is the main source for public water supply and for freshwater input in coastal ecosystems. Moreover, this study underscores the susceptibility of karstic aquifers to salinization, especially in the face of rising sea levels, given their unique hydrogeological characteristics and substantial responsiveness to marine forcings. In spite of the uncertainties in global climate change predictions, this study enhances our understanding of the dynamics of these unique aquifers, and presents future saltwater intrusion projections that offer valuable technical insights to design and implement pertinent and resilient coastal aquifer management strategies.

The analysis of extreme precipitation events plays a crucial role in the management of water resources, infrastructure, public water supply, agriculture, fire control, and public health. For an accurate characterization of precipitation events using historical series, the observed variations must be solely attributable to weather and climate conditions. This study aimed to identify homogeneous gauge stations in Paraná State, southern Brazil, based on four statistical tests (SNHT, Buishand, Pettitt, and Von Neumann) and conduct a homogeneity analysis of daily rainfall data. Missing values were imputed into the time series, and only stations with up to 25% of data gaps were included. Of the 482 stations analyzed in the state, 73.7% ( n = 355) demonstrated homogeneity, 11.6% ( n = 56) were considered doubtful, and 14.7% ( n = 71) were deemed suspect. The highest number of homogeneity breaks was recorded from 1990 to 2005. The number of breaks during this period was estimated at 75 (59.1%) by SNHT, 86 (67.7%) by the Buishand test, and 89 (70.1%) by the Pettitt test. The year with the highest number of homogeneity breaks was 1998, with 81 breaks identified by the Pettitt test. These breaks may be related to El Niño and La Niña phenomena, given that a large sample of rainfall stations was analyzed in the study.