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The Sanitation, Hygiene Education and Water Supply in Bangladesh Programme (SHEWA-B) was a 5-year intervention aiming to improve water, sanitation and hygiene (WASH) practices among 20 million rural residents through community hygiene promoters. This analysis evaluates the impact of SHEWA-B on knowledge, behaviour and childhood diarrhoea outcomes.The evaluation included repeated cross-sectional surveys and health surveillance in matched cohorts in intervention and control clusters. Cross-sectional surveys and structured observations at baseline, midline, and endline assessed the availability of WASH technology, caregiver knowledge and behaviour. Fieldworkers collected monthly health data in a subset of control and intervention households to determine the prevalence of diarrhoea.Of 5091 households surveyed, participants residing in intervention clusters showed minimal improvements in knowledge, reported behaviour, or use of WASH technology compared to the control clusters. During structured observations, intervention households increased more than control households at handwashing before preparing food and after cleaning a baby's anus when comparing endline to baseline, but these changes were not seen when comparing endline to the midline. The prevalence of childhood diarrhoea remained similar in both groups before (10.2% in intervention, 10.0% in control) and after (8.8% in intervention, 11.7% in control) midline changes were made to improve the intervention. Intervention clusters showed no improvement in diarrhoea over time compared to control clusters.SHEWA-B's community-based WASH promotion did not yield the intended impact on knowledge, behaviour or health. Greater priority should be given to approaches that have demonstrated effectiveness. Including rigorous evaluations would broaden the evidence base to support and improve large-scale programmes.

The regulation and permitting of managed aquifer recharge (MAR) has largely been integrated within existing State groundwater regulations. MAR implementation encompasses associated processes that include: (1) source water acquisition and conveyance to the recharge site; (2) source water treatment to ensure compatibility with native groundwater, (3) aquifer capacity to receive recharged water; (4) migration and recovery of recharged water; (5) geochemical reactions of injected water with aquifer matrix and native groundwater; and (6) monitoring and mitigation measures as required. Characterization, design, and operation of the various components involved in successfully recharging groundwater over extended duration is evolving and depends in part on effective coordination and communication between MAR project proponents and regulators. Sustained groundwater availability will depend upon investment in development of effective managed aquifer recharge regulations that are practical, not overly burdensome and support water supply resiliency. MAR has a history of at least 100 years in the United States typically, but not exclusively, in the southwest due to more arid conditions. Regulation and permitting of MAR projects developed over that time vary substantially between states. Implemented properly, MAR project permitting and compliance provide critical oversight to protect water quality and water rights. The MAR regulatory components presented here are intended to inform future development of more consistent and effective regulation across the United States to facilitate investment in their installation and operation.

This study sought to learn how women participated in the recovery process after the Kashmir earthquake of October 2005 in Union Council Langarpura, Azad Kashmir state of Pakistan. Focus-group discussions, semi-structured interviews, and participant observations were conducted with a total of 48 participants. The results revealed that women played various important roles in the reproductive, productive, and community spheres, encompassing, inter alia, normal household responsibilities of cooking, cleaning, and caring for cattle, and non-traditional tasks such as rebuilding the home. In addition, they participated in income-generating activities such as carrying construction materials and water for daily wages, dairy farming, and working in fields and in the education and health sectors. Community endeavours, meanwhile, consisted of search and rescue, caring for the injured, collective cooking and food sharing, and supervising the reconstruction of public structures, including schools, roads, and water supply facilities, and establishing a sewing centre to provide vocational training to local women.هدفت هذه الدراسة إلى التعرف على كيفية مشاركة النساء في عملية التعافي بعد زلزال كشمير في أكتوبر 2005 في مجلس اتحاد لانغاربورا بولاية آزاد كشمير الباكستانية. جرت مناقشات مجموعة التركيز (عددها 2)، والمقابلات شبه المنظمة (عددها 34)، وملاحظات المشاركين بإجمالي بلغ 48 مشاركاً. كشفت النتائج أن النساء في لانغاربورا اضطلعن بمختلف الأدوار المهمة في مجالات الصحة الإنجابية، والإنتاجية، والمجتمعية. تضمنت أدوار النساء واجباتهن المنزلية الاعتيادية المتمثلة في الطهي، والتنظيف، ورعاية الماشية. كما تضمنت مسؤوليات غير تقليدية مثل إعادة بناء منازلهن. كما اضطلعت النساء في لانغاربورا بأدوار إنتاجية تتمثل في المشاركة في الأنشطة المدرة للدخل مثل حمل مواد البناء، والمياه مقابل أجر يومي، والعمل في الحقول، ومزارع الألبان، والعمل في قطاعي التعليم والصحة. من ناحية أخرى، تألفت الأدوار المجتمعية من أنشطة بحث وإنقاذ، ورعاية للمصابين، وطهي جماعي، وتقاسم للطعام، وأدوار غير تقليدية للإشراف على إعادة بناء المباني العامة، بما في ذلك المدارس، والطرق، ومرافق إمدادات المياه، وإنشاء مراكز الخياطة، لتوفير تدريب مهني للمرأة المحلية. عبارات محورية: الزلزال، النوع الجنساني، باكستان ، التعافي، النساء.本研究旨在了解在2005年10月克什米尔地震之后，在巴基斯坦控制的阿扎德克什米尔的琅迦普拉地区（Langarpura）的联合议会，妇女是如何参与恢复进程的。该研究开展了焦点组讨论（n=2）、半结构访谈（n=34）和参与者观察，总计48名参与者参加了研究。结果显示，琅迦普拉地区的妇女在繁衍后代、生产和社区领域扮演了各种重要的角色。妇女在其中扮演的角色，包括做饭、清洁和照顾牛群的常规家庭责任，此外，还包括非传统的责任，比如重建家园。琅迦普拉地区的妇女还扮演了生产领域的角色，包括参加创收活动，如搬运建筑材料和水，以赚取日薪，在田间工作，乳品业劳作，以及从事教育和卫生领域的工作。另一方面，妇女的社区角色包括搜索和救援活动，照顾伤员，集体做饭与共享食物，此外，还包括非传统角色，监督公共设施重建，包括学校、道路和供水设施，以及创办缝纫中心，为当地妇女提供职业培训。 关键词：地震、性别、巴基斯坦、恢复、妇女.

I study the effect of rainfall shocks on child mortality at a sub-national level for a global set of developing countries. I establish that negative (positive) shocks to rainfall lead to an increase (drop) in child deaths overall. Low-income countries (LICs) and the group of countries reliant on agriculture are affected the most due to negative rainfall shocks. In LICs, the impact of negative rainfall shocks is mitigated by around 60% in districts located downstream to dams, an effect predominant among less affluent districts; in addition, the effect of rainfall fluctuations is persistent, lasting for up to three years following the shock. Results remain robust to the inclusion of relevant controls, to the consideration of relevant issues such as selective fertility and migration, and various other robustness tests.

Recharge from preferential flow through mega-thick (100-1000 m) unsaturated zones is a pervasive phenomenon, as demonstrated with a case study of volcanic highland recharge areas in the Great Basin province in southern Nevada, USA. Statistically significant rising water-level trends occur for most study-area wells and resulted from a relatively wet period (1969-2005) in south-central Nevada. Wet and dry winters control water-level trends, with water levels rising within a few months to a year following a wet-winter recharge event and declining during sustained dry periods. Even though a megadrought has persisted since 2000, this drought condition did not preclude major recharge events. Modern groundwater reaching the water table is consistent with previous geochemical studies of the study area that indicate mixing of modern and late Pleistocene recharge water. First-order approximations and simple mixing models of modern and late Pleistocene water indicate that 10% to 40% of recharge is preferential flow and that modern recharge may play a larger role in the water budget than previously thought.

Droughts increasingly threaten the world’s forests and their potential to mitigate climate change. In 2018–2019, Central European forests were hit by two consecutive hotter drought years, an unprecedented phenomenon that is likely to occur more frequently with climate change. Here, we examine tree growth and physiological stress responses (increase in carbon isotope composition; Δδ13C) to this consecutive drought based on tree-rings of dominant tree species in a Central European floodplain forest. Tree growth was not reduced for most species in 2018, indicating that water supply in floodplain forests can partly buffer meteorological water deficits. Drought stress responses in 2018 were comparable to former single drought years but the hotter drought in 2018 induced drought legacies in tree growth while former droughts did not. We observed strong decreases in tree growth and increases in Δδ13C across all tree species in 2019, which are likely driven by the cumulative stress both consecutive hotter droughts exerted. Our results show that consecutive hotter droughts pose a novel threat to forests under climate change, even in forest ecosystems with comparably high levels of water supply.

Reproductive success largely defines the fitness of plant species. Understanding how heat and drought affect plant reproduction is thus key to predicting future plant fitness under rising global temperatures. Recent work suggests reproductive tissues are highly vulnerable to water stress in perennial plants where reproductive sacrifice could preserve plant survival. However, most crop species are annuals where such a strategy would theoretically reduce fitness. We examined the reproductive strategy of tomato (Solanum lycopersicum var. Rheinlands Ruhm) to determine whether water supply to fruits is prioritized above vegetative tissues during drought. Using optical methods, we map xylem cavitation and tissue shrinkage in vegetative and reproductive organs during dehydration to determine the priority of water flow under acute water stress. Stems and peduncles of tomato showed significantly greater xylem cavitation resistance than leaves. This maintenance of intact water supply enabled tomato fruit to continue expanding during acute water stress, utilising xylem water made available by tissue collapse and early cavitation of leaves. Here, tomato plants prioritize water supply to reproductive tissues, maintaining fruit development under drought conditions. These results emphasize the critical role of water transport in shaping life history and suggest a broad relevance of hydraulic prioritization in plant ecology. This article is protected by copyright. All rights reserved.

In the summer of 1976, north-west Europe experienced an exceptional heatwave and drought, which impacted agriculture and public water supply. This study aims to assess how the likelihood of the event in the present-day climate has changed since 1976 due to climate change. The analysis focuses on the England and Wales region, which was particularly badly impacted. Three key factors contributing to the extreme summer were identified: the dry preceding winter–spring period, the dry summer and the hot summer. Following the principles of event attribution, three methods are used to evaluate the change in event risk: one using observational data, a second using CMIP5 coupled climate models, and a third using HadGEM3-A atmosphere-only simulations. This is the first time that this method has been used to evaluate how the risk of a historical extreme event has changed since it originally occurred. The results from the three methods agree qualitatively. The probability of a summer at least as hot as 1976 has increased significantly between 1970s and the present-day climate (estimated risk ratios 11 (5–95% confidence interval (CI) [7, 14]), 9 (CI [4, 28]) and 19 (CI [5, 25]) based on the three respective methods). In contrast, no significant change in the probability of an extreme dry winter–spring or an extreme dry summer was found. However, the joint probability of an extreme dry winter-spring followed by an extreme hot summer, and the probability of an extreme hot and dry summer, have both increased significantly between the 1970s and the present day (estimated risk ratios between 5 and 79, and between 3 and 39, respectively). Water resource systems should therefore be robust enough to cope with more frequent occurrences of summers as extreme as 1976.

BACKGROUND Water is critical to the production of crops, especially when faced with seasonal drought or freshwater scarcity. We compared the effect of negative pressure irrigation (NPI) on water use efficiency (WUE), nutrient uptake, yield and quality of Brassica chinensis L. using a greenhouse plot experiment. Three different water supply pressures (-5, -10 and -15 kPa), and a conventional irrigation (CK) treatment, were arranged in a randomized design with three replications. RESULTS Our results suggest that plant height, leaf area, number of leaves and ratio of root to shoot were significantly correlated with water supply pressure. Specifically, our results show that B. chinensis L. yield was increased 50% with NPI versus CK. Water supply pressure had a significant effect on N and P nutrient uptake and no significant effect on K. The average concentration of vitamin C was greatest with -5 kPa treatment and consecutively declined. According to our results, NPI can save up to 36.8% of water used and improve WUE by 61.3% during growth of B. chinensis L. Our results suggest that the optimum irrigation management strategy is -5 kPa treatment. CONCLUSION NPI versus CK can provide more stable irrigation water and retain soil moisture during plant growth, resulting in an increased WUE and yield with suitable water supply pressure. While our results suggest that NPI can enhance B. chinensis L. yield and perhaps also quality, future research should explore the mechanism of NPI in relation to yield and water use efficiency. © 2021 Society of Chemical Industry.

This study is among the first to investigate whether patterns of access to basic services could explain the disproportionately severe impact of COVID-19 in slums. Using geolocated containment zones and COVID-19 case data for Mumbai, India?s most populous city, we find that cases and case fatality rates are higher in slums compared to formal residential buildings. Our results show that access to toilets for men is associated with lower COVID-19 prevalence. However, the effect is opposite in the case of toilets for women. This could be because limited hours for safely using toilets and higher waiting times increase risk of exposure, and women and children sharing toilet facilities results in crowding. Proximity to water pipelines has no effect on prevalence, likely because slumdwellers are disconnected from formal water supply networks. Indoor crowding does not seem to have an effect on case prevalence. Finally, while police capacity ? measured by number of police station outposts ? is associated with lower prevalence in non-slum areas, indicating effective enforcement of containment, this relationship does not hold in slums. The study highlights the urgency of finding viable solutions for slum improvement and upgrading to mitigate the effects of contagion for some of the most vulnerable populations. This article is protected by copyright. All rights reserved.

We analyze the problem of allocating irrigation water among het- erogenous farmers when water supply is stochastic. If farmers are risk-neutral, a spot market for water is e¢ cient; while the oft-used uniform rationing system is ine¢ cient, both ex-ante and ex-post. In- deed, we show that it leads farmers to overexpose to risk, thus making shortages more severe and more frequent in case of drought. We pro- pose instead a regulation by priority classes extending Wilson (1989), and we derive an e¢ ciency result. We characterize the set of farmers that would win or loose from such a reform. We also argue that a system of priority classes may be preferred to a spot market system, because scarcity is easier to manage ex-ante than ex-post, and because this system facilitates the supply of insurance to risk-averse agents.

Many of the world's major aquifers are under severe stress as a result of intensive pumping to support irrigated agriculture and provide drinking water supplies for millions. The question of what the future holds for these aquifers is one of global importance. Without better information about subsurface conditions, it will be difficult to reliably assess an aquifer's response to management actions and climatic stresses. One important but underutilized source of information is the data from monitoring well networks that provide near-continuous records of water levels through time. Most organizations running these networks are, by necessity, primarily focused on network maintenance. The result is that relatively little attention is given to interpretation of the acquired hydrographs. However, embedded in those hydrographs is valuable information about subsurface conditions and aquifer responses to natural and anthropogenic stresses. We demonstrate the range of insights that can be gleaned from such hydrographs using data from the High Plains aquifer index well network of the Kansas Geological Survey. We show how information about an aquifer's hydraulic state and lateral extent, the nature of recharge, the hydraulic connection to the aquifer and nearby pumping wells, and the expected response to conservation-based pumping reductions can be extracted from these hydrographs. The value of this information is dependent on accurate water-level measurements; errors in those measurements can make it difficult to fully exploit the insights that water-well hydrographs can provide. We therefore conclude by presenting measures that can help reduce the potential for such errors.

Deep-water access is arguably the most effective, but under-studied, mechanism that plants employ to survive during drought. Vulnerability to embolism and hydraulic safety margins can predict mortality risk at given levels of dehydration, but deep-water access may delay plant dehydration. Here, we tested the role of deep-water access in enabling survival within a diverse tropical forest community in Panama using a novel data-model approach. We inversely estimated the effective rooting depth (ERD, as the average depth of water extraction), for 29 canopy species by linking diameter growth dynamics (1990-2015) to vapor pressure deficit, water potentials in the whole-soil column, and leaf hydraulic vulnerability curves. We validated ERD estimates against existing isotopic data of potential water-access depths. Across species, deeper ERD was associated with higher maximum stem hydraulic conductivity, greater vulnerability to xylem embolism, narrower safety margins, and lower mortality rates during extreme droughts over 35years (1981-2015) among evergreen species. Species exposure to water stress declined with deeper ERD indicating that trees compensate for water stress-related mortality risk through deep-water access. The role of deep-water access in mitigating mortality of hydraulically-vulnerable trees has important implications for our predictive understanding of forest dynamics under current and future climates.

Nature based solutions (NBS) can be used in combination with reopening of piped rivers to support area development. In certain cases, piped rivers can run through disused landfills and this presents a complicating factor as the landfills provide the possibility for river water to be contaminated by waste. In Skien municipality close to Oslo, Norway, NBS are being considered as part of a potential reopening of the Kjorbekk stream. A 4 km stretch of the stream is contained in an aging pipe infrastructure that is buried under two disused landfills. The pipe infrastructure does not have the physical capacity to cope with an increase in precipitation that accompanies current climate change, and in certain areas, the pipe has started to leak. This means that surface water run off that cannot be accommodated by the pipe, as well as water that leaks from the pipe can become contaminated by the waste in the disused landfill. The water can furthermore be transported with the stream course to the final recipient, taking the contamination with it. Reopening the stream and providing new water pathways can alleviate these problems, but it must be carried out in such a way that contamination is not spread. This case study shows how certain NBS that focus on reducing the amount of water in contact with pollutants, reducing the amount of particle spreading, remediating contaminated water and remediating contaminated soil, could be implemented at the site and function as a catalyst for an incremental city development. Key Points: The kjorbekk stream runs in an old pipe infrastructure which is unable to accommodate the increase in rainfall predicted via climate change. The pipe runs through two disused landfill sites which were built without bottom membranes and waste in the landfill has the potential to contaminate excess rainfall water that it comes into contact with. Nature based solutions are being considered in combination with reopening of the kjorbekk stream, however they must ensure that the pollutants are not mobilized and do not result in a wider area becoming contaminated. This article is protected by copyright. All rights reserved.

The US Army Corps of Engineers (USACE) manages hundreds of reservoirs and thousands of miles of navigation channels that provide invaluable flood control, commercial transport of materials, water supply, recreation, and stream flow regulation. This capability is being threatened by the continued occurrence of large-scale wildfires across the western United States. The wildfires damage watersheds in part by denuding landscapes, reducing infiltration rates, and increasing runoff rates, thereby dramatically increasing the potential for the erosion of denuded slopes, destabilizing stream channels, increasing the infilling potential of reservoirs and, hence, reducing their capacity. The increased erosion rates highlight the need to develop innovative solutions to reduce erosion of watersheds laid bare after wildfires engulf the area. The Santa Clara Pueblo in northern New Mexico extends from the top of the eastern Jemez Mountains to the floodplains of the Rio Grande River. The Pueblo designed and constructed thousands of structures built from natural materials, consistent with Engineering With Nature (EWN) principles for erosion control incorporating low-cost and readily available materials such as logs, mulch, vegetation, and local rock to stabilize highly erodible parts of the watershed. The watersheds where these natural structures were constructed were monitored after construction to assess their effectiveness, guiding a series of recommendations for broader implementation. As part of a continued emphasis on updating USACE engineering guidance, research, and development, funding has been focused on developing sustainable and resilient project designs using natural materials like those implemented by the Santa Clara Pueblo. This paper focuses on the innovative EWN-based watershed stabilization practices that were implemented in the upper section of this wildfire affected canyon and tributary streams. Recommendations for future implementation based on lessons learned from this project are also provided. Integr Environ Assess Manag 2021;17:1194-1202. Published 2021. This article is a US Government work and is in the public domain in the USA.

Models based on the Kumaraswamy law are used with variables that assume values in (0, 1). In some cases, however, the data contain zeros and/or ones, that is, there is data inflation. We introduce a class of regression models that can be used with such inflated data, namely: the class of inflated Kumaraswamy regression models. We consider inflation at zero, at one, and at both zero and one. We introduce the model and provide closed‐form expressions for its score vector and Fisher's information matrix. The proposed model is used to evaluate the impacts of different conditioning variables on the proportion of people who live in households with inadequate water supply and sewage in Brazilian municipalities. Our results reveal that policies directed to increasing the population share with college education in places where it is low are particularly effective in reducing the prevalence of people who live under inadequate sanitation conditions.

Unidad de excelencia María de Maeztu CEX2019-000940-M BACKGROUND: Urban agriculture contributes to meet food production demand in cities. In a context of low water availability, it is important to consider alternatives that are able to maintain production. This study aimed to assess the use of substrates made from local materials and high water retention capacity as an alternative for urban agriculture in periods with water stress. Different substrates were used for 3 consecutive crop cycles of lettuce (Lactuca sativa L.) during the spring and summer periods of 2018 to observe these substrates performance during warmer periods of the year in an integrated rooftop greenhouse near Barcelona. The substrates used were coir commercial organic substrate, vegetable Compost from urban organic waste, Perlite (as control) commercial standard substrate, and a Mixture of the urban Compost and Perlite (1:1). Substrate crop performance was assessed under conventionally irrigation (0-5 cbar) and water restricted conditions (irrigation stop until the water tension inside the perlite bags reached -20 cbar). RESULTS: The results demonstrate that the Compost and Mix yields were similar to those obtained from Perlite (11.5% y 3.7% of more production in a restricted water condition average values). Compared to the Perlite, the organic substrates increased the crops resilience to water restriction, through biomass accumulation comparison, it took longer for Coir to lose water (1 and 2 test); however, when dryness began, it occurred very quickly. CONCLUSION: The vegetable Compost and the substrate Mixture presented tolerance to water restriction when water restriction reached -20 cbar.

BACKGROUND: In explaining and predicting spatial vegetation patterns, ecologists have increasingly favoured the use of climatic water balance variables, including actual evapotranspiration (AET) and climatic water deficit (CWD), for representing the hydrologic and energetic environment experienced by plants. Much of the interest in these variables lies in their hypothesized potential to characterize biologically relevant environmental variation more directly than simple climate variables, such as precipitation and temperature. Practically, obtaining AET and CWD values across space requires hydrologic process models that involve assumptions, including assumptions about vegetation transpiration rates. However, transpiration parameter values are rarely known with precision and can vary several‐fold within and among vegetation types. APPROACH: We evaluate the extent to which assumptions about vegetation physiology in water balance models affect (a) relative spatial variation in modelled water balance values and (b) ecological inferences that are derived from analyses using water balance variables. We demonstrate an approach for identifying inferences that are robust to these assumptions. RESULTS: Assumptions about vegetation physiology can substantially affect relative spatial variation in modelled water balance values. More importantly, such assumptions can also substantially affect the inferences (e.g., expected vegetation distributions) drawn from ecological analyses that use water balance variables as predictors. Water balance variables are less sensitive to assumptions in environmental settings with abundant water supply, where AET variation is driven primarily by available energy (e.g., temperature and insolation), but they can be highly sensitive to assumptions in drier environments. CONCLUSION: Because of their sensitivity to assumptions, water balance variables are not unambiguously superior to simpler climatic and topographic variables, such as precipitation and temperature. However, they retain some advantages, primarily related to their mechanistic incorporation of interactions between water and energy, which may support their use in applications where sensitivity to hydrologic modelling assumptions is low or of minor concern.

Due to increasing water demands globally, freshwater ecosystems are under constant pressure. Groundwater resources, as the main source of accessible freshwater, are crucially important for irrigation worldwide. Over-abstraction of groundwater leads to declines in groundwater levels; consequently, the groundwater inflow to streams decreases. The reduction in baseflow and alteration of the streamflow regime can potentially have an adverse effect on groundwater-dependent ecosystems. A spatially distributed, coupled groundwater-surface water model can simulate the impacts of groundwater abstraction on aquatic ecosystems. A constrained optimization algorithm and a simulation model in combination can provide an objective tool for the water practitioner to evaluate the interplay between economic benefits of groundwater abstractions and requirements to environmental flow. In this study, a holistic catchment-scale groundwater abstraction optimization framework has been developed that allows for a spatially explicit optimization of groundwater abstraction, while fulfilling a predefined maximum allowed reduction of streamflow (baseflow [Q95] or median flow [Q50]) as constraint criteria for 1484 stream locations across the catchment. A balanced K-Means clustering method was implemented to reduce the computational burden of the optimization. The model parameters and observation uncertainties calculated based on Bayesian linear theory allow for a risk assessment on the optimized groundwater abstraction values. The results from different optimization scenarios indicated that using the linear programming optimization algorithm in conjunction with integrated models provides valuable information for guiding the water practitioners in designing an effective groundwater abstraction plan with the consideration of environmental flow criteria important for the ecological status of the entire system.

Objectives\ud To determine the prevalence of dental fluorosis, and factors associated with its occurrence in two cohorts of children exposed to different fluoride concentrations in the Malaysian water supply.\ud \ud Methods\ud A cross‐sectional study was conducted among lifelong residents (n = 1,155) aged 9 and 12 years old living in fluoridated and nonfluoridated areas. Malaysian children aged 12 years were born when the level of fluoride in the public water supply was 0.7 ppm while those aged 9 years were born after the level was reduced to 0.5 ppm. Fluorosis was blind scored using standardized photographs of maxillary central incisors using Dean's criteria. Fluoride exposures and other factors were assessed by parental questionnaire. Data were analyzed using descriptive statistics, Chi‐squared analyses, and logistic regression.\ud \ud Results\ud Fluorosis prevalence was lower (31.9 percent) among the younger children born after the reduction of fluoride concentration in the water, compared to a prevalence of 38.4 percent in the older cohort. Early tooth brushing practices and fluoridated toothpaste were not statistically associated with fluorosis status. However, the prevalence of fluorosis was significantly associated with parents' education level, parents' income, fluoridated water, type of infant feeding method, age breast feeding ceased, use of formula milk, duration of formula milk intake, and type of water used to reconstitute formula milk via simple logistic regression. Fluoridated water remained a significant risk factor for fluorosis in multiple logistic regression.\ud \ud Conclusions\ud Fluorosis was lower among children born after the adjustment of fluoride concentration in the water. Fluoridated water remained as a strong risk factor for fluorosis after downward adjustment of its fluoride concentration.

Understanding the water consumption patterns within a specific population informs development of increasingly accurate, spatially specific exposure and/or risk assessment of waterborne infection. The current study examined the consumption patterns of private well users in Ontario while considering potentially influential underlying sociodemographics, household characteristics, and experiential factors. A province-wide online survey was circulated between May and August 2018 (n = 1,162). Overall, 81.5% of respondents reported daily well water consumption (i.e., tap water). Results indicate a mean daily well water consumption rate of 1,132 mL/day (SD = 649 mL/day) among well water consumers. Gender was significantly associated with well water consumption, with higher consumption rates found among female respondents. The experience of acute gastrointestinal illness (AGI) symptoms or diagnosis in the past 12 months did not impact the volume of water consumed, suggesting that experiencing previous AGI does not decrease consumption volumes, and therefore exposure over time. Significantly higher rates of well water consumption were found among respondents who reported previous testing or ongoing water treatment. Approximately 45.5% of survey respondents who stated that they do not consume well water selected bottled water as their primary household drinking water supply. Bottled water consumption was also not associated with previous AGI experiences. Findings will inform future quantitative microbial risk assessments associated with private well water use by providing spatially and demographically specific estimates of well water consumption.

Time-domain analytical solution for groundwater flow to a fully penetrating flowing well is derived using the same substitution technique used to re-derive (Perina 2010) the Theis (1935) equation and the approximate solution by Mishra and Guyonnet (1992) is confirmed. The exponential integral-based flowing well function is a computationally effective alternative to the original Jacob and Lohman (1952) solution in integral form. For a constant drawdown test, the ratio of drawdown at an observation well to the flowrate is equivalent to drawdown response to pumping at unit constant rate; the transformed observations can be analyzed using the Theis (1935) function. Analysis of field test shows that simultaneous fitting to measurements of flow from the test well and drawdown at an observation well results in more accurate and better resolved estimates of aquifer properties than fitting to flow observations only.

Environmental disasters impact disadvantaged communities disproportionately both through the epidemiological challenge of exposure, but also by undermining the progress of public health efforts. This paper studies changes to smoking cessation, breastfeeding, and weight gain during pregnancy in the period following the switch in water supply in Flint, Michigan, in April 2014. As the switch resulted in immediate and significant deterioration in water quality, eventually leading to its contamination with lead, we estimate a 10.5 percentage point increase in smoking and a 2.1 percentage point decrease in breastfeeding. We show evidence that these changes in maternal behavior are linked to increased stress due to changing water quality. We estimate that the increase in smoking alone is responsible for most of the increase in incidence of low birthweight among infants in Flint, resulting in $700 additional costs per birth. Increased smoking during pregnancy and lower breastfeeding rates in Flint roll back years of public health efforts, resulting in lifetime higher rates of cardiovascular disease, diabetes, and cancer for mothers in the community.

This paper deals with water pumping cost minimization, in a confined infinite aquifer, proposing an alternate pulsed pumping schedule. The transient flow analysis is conducted for two wells with equal pumping rates. Specifically, two pumping schedules are analytically compared. In the first case, well users pump simultaneously, and in the second one they cooperate so that they pump alternately. This paper proves that the proposed alternate pumping schedule works as a stabilizer, reducing the high hydraulic drawdowns values, regardless of the aquifer characteristics. Moreover, pumping alternately is better in terms of pumping cost, compared to simultaneous pumping, though benefit become negligible as distance between wells becomes large. Two simplified equations are proposed, one to find the difference of the hydraulic drawdowns between the two pumping schedules and the other one to find the economic benefit of each well from cooperation. The equations are finally applied to a number of cases and their results are compared to the results obtained from an algorithm created to calculate the hydraulic drawdowns and the pumping cost, using the Theis equation. The results can be very useful in irrigation scheduling, as they can be applied to systems of well users/farmers, to reduce pumping cost.