Public Water Supply Research Articles

Gerasa’s ‘Nymphaeum’: a reappraisal of its history and function

The Decapolis town of Gerasa became a sizeable urban centre in the province of Arabia in the 2nd century CE. The study of its monumental fountain, the so-called Nymphaeum, has been neglected despite its excellent state of preservation. This small but imposing late 2nd-century monument functioned as an aesthetic display and public water supply, although public access was restricted to the frontal spouts. This article comprehensively reappraises the evidence, identifying new material and providing a diachronic analysis of the monument’s function and hydraulic operation. It is proposed that the original monument was also designed to supply secondary fountain installations. The later extension of this role to supply the expanded Cardo fountain network, marked a change to a wholly utilitarian function. Later changes included the removal of a previously added wall to the parapet and spout modifications. Subsequent earthquakes severely damaged the monument, and it remained in a ruinous state until cleared in the mid-1920s.

Water Supply Processes Are Responsible for Significant Nitrogen Fluxes Across the United States

AbstractExcessive nutrient concentrations within fresh waters are a globally persistent problem. Developing effective nutrient management strategies requires improvements to nitrogen (N) mass balances, including the identification and quantification of previously unrecognized anthropogenic N fluxes. Using publicly available data, we establish that freshwater abstractions from both surface waters and groundwaters, alongside watermains leakage from public distribution networks, are responsible for significant nitrate‐N (NO3‐N) fluxes across the contiguous United States. Nationally, freshwater abstraction temporarily retains 417 (min‐max: 190–857) kt NO3‐N yr−1, equivalent to 21% of pastureland N uptake and 2% of previous global abstraction‐N flux estimates. Fluxes due to irrigation, thermoelectric power, and public water supply collectively account for 87% of this total. We find large intercounty variation in area‐normalized abstraction fluxes (min‐max: 0–8,267 kg NO3‐N km−2 yr−1), with eastern regions generally associated with larger fluxes. Watermains leakage returns 7 (min‐max: 6.3–7.7) kt NO3‐N yr−1 back to the environment, equivalent to 13% of NO3‐N initially abstracted for public supply and 1.3% of previous global leakage flux estimates. Our analyses reveal inter‐county variations in area‐normalized leakage fluxes (min‐max: 0–576 kg NO3‐N km−2 yr−1), with this flux exceeding other major N inputs (agricultural N fertilizer) in some urbanized and coastal counties, highlighting their importance in these areas. The local and national importance of these fluxes has implications for policy makers and water resource managers aiming to better manage the impacts of N within the environment and calls for their inclusion in both US and global N budgets.

Device Provides Proof of Public Water Supply

Device Provides Proof of Public Water Supply

Failure mode effects and criticality analysis of water supply systems' risks: Path to water resources planning and policy

AbstractThe risk assessment of drinking‐water supply systems in Ogun State, Nigeria, was carried out using the failure mode effects and criticality analysis (FMECA) approach. The FMECA is a systemic process that identifies potentials failure modes within a system and was chosen for its causes and effect approach to assessing risks. The objective of the study was to assess drinking‐water supply systems and identify water supply systems' risks from source to point‐of‐use. Three major water supply sources were selected for assessment: hand‐dug wells, boreholes and public water supply sources. The sources were assessed by identifying the potential failure modes that exist within the water supply sources and the consequence of the identified risks on relevant stakeholders. The sources were divided into modules. The risk in each module was determined by multiplying failure rate (likelihood) and consequences of failure of the module. Risk reduction options include repair and maintenance measures, information dissemination on the procedures to reduce the identified risks and preventive and regulatory approaches. The resulting risks were characterized using FMECA risk matrix of each water source and classified into high, medium and low risks. Well cover and lining were the most risk‐prone modules for hand‐dug wells (high and medium risks). Broken well cover and lining serve as pathways to contaminants into the well. Casing and screen modules posed the highest risk for boreholes, recording high to medium risk. Cracked casing and broken screen provide access for contamination into boreholes. The module with the greatest risk for public water supply source was the point‐of‐abstraction/use module. Unsanitary containers and poor storage conditions is believed to be responsible for recontamination of the treated water Climate variability, environmental and anthropogenic influences were observed to be responsible for most of the identified risks. The study highlights that consumer participation is vital in ensuring the availability of safe drinking‐water, stressing consumer education as the most important channel. The study recommends the use of FMECA to ensure implementing preventive and regulatory measures by water monitoring agencies and for water resources planning and policy making.

The environmental impact of community caries prevention - part 3: water fluoridation.

Introduction Community-level interventions for the prevention of dental caries in children include fluoride varnish in schools, supervised toothbrushing in schools, the provision of toothbrushes and toothpaste and water fluoridation. The environmental impact of these interventions is an important factor to consider when commissioning these services.Materials and methods A comparative life cycle assessment (LCA) was conducted to quantify the environmental impact of fluoridation of the public water supply for a five-year-old child over a one-year period. These results were compared to LCA data for fluoride varnish in schools, supervised toothbrushing and the provision of toothbrushes and toothpaste.Results When comparing community-level caries prevention programmes, water fluoridation had the lowest environmental impact in all 16 categories and had the lowest disability-adjusted life years impact.Discussion All community-level caries prevention programmes have an associated environmental cost. Water fluoridation performed well in this LCA study in all measures of environmental sustainability. The results of this study could be used, along with cost and clinical effectiveness data, to inform public healthcare policy.

Improvement of Onsite Wastewater Systems Performance: Experimental and Numerical Investigation

Population growth and the associated increase in the use of Onsite Wastewater Treatment Systems (OWTS) in the Black Hills have been a reason for interest in nitrate contamination within the public water supply over the past few years. The main concern for the Black Hills is the presence of karst formation that all OWTS for wastewater travel faster, limiting the natural attenuation of wastewater contaminants. The treatment performance of common soils in the Black Hills and wood-based media was evaluated using soil column experiments and a numerical model, HYDRUS 2D. Nitrate treatment performances were evaluated using alluvial and cedar soils collected from the Black Hills, sand, woodchips (loose and dense), and biochar. This research investigated hydraulic and reaction parameters through a combination of experimental and inverse modeling approaches. A good agreement was obtained between the measured and model-predicted soil moisture content, with R2 values ranging from 0.57 to 0.99. The model was calibrated using flow data and nitrate concentration data measured from leachate collected at the bottom of the experimental columns. Nitrate removal rates varied from 32.3% to 70%, with the highest removal rate in loose woodchips, followed by dense woodchip and biochar, and the lowest removal rate in alluvial materials. The biochar and loose woodchips removed an additional 20% compared to common soils, attributable to the enhanced denitrification rate due to higher water content and organic content. The use of woodchips and biochar should be implemented in OWTS, where there are known karst formations.

Where you drink water: An assessment of the Tennessee, USA public water supply.

Monitoring drinking water quality is essential to protect people's health and wellbeing. In the United States, the Safe Drinking Water Information System (SDWIS) database records the occurrence of a drinking water violation regulation in public water systems. A notable shortcoming of SDWIS is the lack of the contaminant concentration level about the allowable maximum contaminant threshold. In this study, we take advantage of both the SDWIS violation database and the contaminants sampling database at the state level to examine the drinking water quality of all kinds of drinking water systems in detail. We obtained sampling data (i.e., the concentration level of contaminants) of public water systems (PWSs) in Tennessee and explored the statistical distribution of contaminant concentration data in relation to the enforceable maximum regulatory contaminant level). We use both SDWIS violation records and actual concentrations of contaminants from the sampling data to study the factors that influence the drinking water quality of PWSs. We find that different types of violations were more frequent in (1) specific geological regions, (2) counties with PWSs that serve a larger population (10,000 to 100,000 people), and (3) places with abundant surface water, such as near a lake or major river. Additionally, the distribution of measured concentrations for many contaminants was not smooth but was punctuated by discontinuities at selected levels, such as at 50% of the maximum contaminant level. Such anomalies in the sampling data do not indicate violations, but more investigation is needed to determine the reasons behind the punctuated changes.

Biomass and essential oil production of basil at recirculation intervals of nutrient solutions prepared with treated domestic effluents

Considering the growing water crisis, using wastewater helps reduce the pressure on good-quality water consumption. In this context, this study aimed to evaluate the growth, production, and essential oil content of Alfavaca Basilicão and Grecco a Palla basil genotypes with a DFT (deep flow technique) hydroponic system adapted to PVC tubes at different recirculation intervals of nutrient solutions prepared with treated domestic effluents. The experiment was performed in a greenhouse with Alfavaca Basilicão and Grecco a Palla basil genotypes analyzed individually. It was a completely randomized design with four replicates in a 2 x 3 factorial scheme: two types of water (public-supply water and wastewater) and three recirculation intervals of nutrient solutions (2, 4, and 6 hours). At 35 days after transplanting, the study evaluated plant height, stem diameter, shoot fresh mass, shoot dry mass, water consumption, water use efficiency, and essential oil content and yield. The types of water did not significantly influence the variables of growth, production, and essential oil content of the basil genotypes. Basil cultivation with the DFT system in tubes is technically feasible with nutrient solutions prepared with treated domestic effluents and recirculation every 2 and 6 hours for Grecco a Palla and Alfavaca Basilicão genotypes, respectively. The means of essential oil content were 1.6 and 1.7% (v/m) for Alfavaca Basilicão and Grecco a Palla genotypes, respectively.

Dental Fluorosis and Its Associated Factors Amongst Libyan Schoolchildren

BackgroundLittle is known about dental fluorosis (DF) in Benghazi, Libya, where the public water supply is naturally fluoridated. ObjectiveThe study aims to investigate the distribution of DF and its related risk factors and impact on oral health–related quality of life (OHRQoL) and the association between DF and caries amongst Libyan school children. MethodsA cross-sectional survey was carried out amongst 12-year-old schoolchildren in the city of Benghazi. Dean's and decayed, missing, and filled surfaces (DMF) indices were used to assess the severity of DF and dental caries. In addition, a self-administered questionnaire was used to collect sociodemographic and behavioural information and OHRQoL using the Child Oral Health Impact Profile–Short Version 19 (COHIP-SF19). ResultsOut of 1125 children who participated in the study, 15%, 7.8%, 2.2%, and 0.4% of participants were coded as having questionable, mild, moderate, and severe DF, respectively. Children enrolled in private schools were less likely to have DF (odds ratio, 0.55; 95% confidence interval, 0.35–0.83; P = .007). Moderate-severe DF was associated with more decayed surfaces and DMF scores and low scores for COHIP-SF19 and its socioemotional well-being subscale. ConclusionsThe data demonstrate that rates of DF are relatively low in naturally fluoridated areas in Libya. DF amongst Libyan schoolchildren was associated with social disparities, higher caries rates, and negative impacts on OHRQoL.

Cleaner construction of durable green rooftop in residential buildings with municipal water supply

Rooftop vegetation is a popular choice among architects and builders at present because of its aesthetical appeal and environmental benefits. It has consistently been regarded as a sustainable and eco-friendly approach to the construction of buildings. Recently, people have adopted rooftop vegetation in their homes, and it has become popular. Large scale roof gardens in commercial buildings are safe due to proper design and protection techniques by experts. Due to economic constraints, rooftop vegetation in normal residential buildings cannot follow stringent regulations and expensive protection techniques. However, it is to be kept in mind that any rooftop vegetation endeavour, if not properly designed and maintained, might result in severe durability problems in roof concrete. There are unseen drawbacks to simple practices of concrete rooftop vegetation in common residential buildings, specifically the presence of aggressive agents in treated water from the public water supply, which is commonly used to irrigate the vegetation in such buildings. The effect of vegetation on the concrete roof and its influence on various salient aspects, specifically the durability of concrete, is discussed in this paper. The influence of chlorides and sulphates present in the municipal treated water used for watering plants and shrubs on the durability of concrete is also presented. Moreover, the chloride threshold value of the reinforcement is between 0.1% and 1.5%. The total charges passed through concrete are also reduced to less than 1000 Columbus with the addition of agricultural by-products. In addition, root intrusion tendency of commonly grown plants on rooftop and corrosion due to agricultural chemicals are also mentioned. In the latter sections, remedial measures are highlighted to minimize the negative impacts of rooftop vegetation on the durability of concrete. In addition, to highlight the impact of chlorides on the roof concrete, the study also presented the chloride permeability and service life of blended concrete.

Panorama of the water supply in the Campinas region and a brief comparison with other regions in the Southeast of Brazil

Access to drinking water is one of the most important factors for health. The lack of access to safe drinking water results in a high prevalence of infections, such as bacterial gastroenteritis and outbreaks of diarrhea. This study evaluated the quality of the public water supply in 42 municipalities located in the eastern region of the State of São Paulo, Brazil, from 2016 to 2020. Physical, chemical, and microbiological parameters were investigated. Sample collection, preservation and analyses were carried out in accordance with national and international standards. The results demonstrated non-compliance with Brazilian legislation for apparent color (1.1%), turbidity (0.4%), fluoride content (14.2%), total coliforms (4.4%) and Escherichia coli (E. coli) (0.4%). In a brief comparison with other studies in the southeastern region of Brazil, the highest percentage of unsatisfactory samples is due to the fact that fluorine is below the minimum of <0.6 ppm, demonstrating the need for training in the fluoridation process. The need to invest in the training of health surveillance teams to carry out field analyses (chlorine and pH) was also observed. This study can inform future actions, guiding the adoption of preventive and corrective measures and demonstrating the importance of monitoring water-supply quality.
 Keywords: drinking water, public health, water quality.

Women's participation in disaster recovery after the 2005 Kashmir, Pakistan earthquake.

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.

The challenge of urban food production and sustainable water use: Current situation and future perspectives of the urban agriculture in Brazil and Italy

• Tap water use in urban agriculture albeit climate change/urban water risk scenarios. • No studies addressed impacts of urban agriculture on public water supply systems. • Research need on urban agriculture policies and practices towards water security. • Fruit trees and wild edible plants are water-saving options. Urban agriculture (UA) initiatives have been increasing in recent years as a nature-based solution for achieving many of the 2030 UN Sustainable Development Goals. However, climate change is expected to have effects on rainfall patterns, which are likely to impact urban food production. The main aim of this paper is to evaluate how issues related to water sources for UA have been addressed in the scientific literature from two different socioeconomic and environmental realities, Brazil and Italy. The method involved a systematic literature review, considering the PRISMA guidelines. The Web of Science database and papers' reference lists were used for retrieving original articles, published in 2000–2020 interval, indexed on scientific databases, and containing data on the typology and quality of water sources used in UA studies. After applying the eligibility criteria, 191 papers were selected – Brazil (108) and Italy (83). The last five years have seen an intensification of studies into issues involving water. Tap water has been identified as an important source of irrigation water for UA, if not the main one. No studies were found that addressed the impact of UA on public water supply systems. The findings point towards more sustainable practices involving the reuse of water and adaptive practices towards water security. We identified that innovative production systems like container farming, aquaponics and indoor agriculture, as well as cultivation of fruit trees, wild edible plants and varieties with low water requirements can represent water-saving options.

Possibilities of Romania to achieve Objective 11 – “Sustainable cities and communities” under the 2030 Sustainable Development Strategy

Abstract The paper represents an analysis of Romania’s possibilities of achieving Objective 11 of the 2030 Sustainable Development Strategy, entitled “Sustainable Cities and Communities”. In order to determine the possibilities to achieve the objective, the average evolution rate method was used to predict the evolution of the indicator “share of the population served by the public water supply system” until 2030. Also, given the very large regional gaps between the 8 development regions of Romania, with the help of the rank method, the regions were ranked according to three important indicators that can be the basis for achieving objective 11, respectively: the share of the population served by the public water supply system; gross investments in tangible goods from local units active in the production and supply of electricity and heat, gas, hot water and air conditioning and water distribution and sanitation, waste management, decontamination activities, per capita and gross domestic product per capita.

Special issue: NBS for resilient cities and communities — How understanding the micro components of domestic water consumption can provide multiple water uses to facilitate a transition to a Circular Economy of Water

Resilient cities and communities of the future will require a Circular Economy of Water (CEW), where used water is either reused with minimal treatment and/or separated at source, collected, treated and recycled on or off site to provide a “Fit for Purpose” water. Understanding the micro components of household water use and the different used waters generated is an important first step in this approach. This paper presents results from two separate studies. The first study monitored household water use in four households over a continuous 24-month period in Ireland. Meters were installed to monitor public mains water supply, toilet flushing, hot water, cold water supply to taps and water supply to kitchen. Daily water use profiles were generated. Per capita consumption rates varied from 71 L/hd/day to 132 L/hd/day. This compares to a national average in Ireland of 129 L/hd.d. These variations reflect the diversity between homes in terms of the way occupants utilise water for different practices (personal hygiene, laundry, kitchen, WC use). Averaging the results across all study households, for every 100 L of potable mains water supplied to the household, 28 L was flushed down the toilet, 22 L was used in the hot water system, 17 L was supplied to cold water taps for personal hygiene uses and 33 L was used in the kitchen. This study compares with results from an EU study compiled by the authors where over 75% of household water use across selected EU countries was also used for bathing and showering, WC flushing and laundry. Trends show that household water use has reduced across all selected countries in recent years. The influence of water meters in achieving this reduction is evident in the EU data. This effect is particularly evident from England and Wales, where water use in unmetered households is estimated to be 30% higher than metered households. The data shows that universal metering, increased water charges and a national focus on water efficiency and demand management programs can achieve significant reductions in household water consumption. The authors propose a Circular Economy of Water hierarchy focused on Reduce, Reuse, Recycle and Recover. A twelve step approach is suggested to facilitate this transition to a water smart society.

Review of Community-Managed Water Supply—Factors Affecting Its Long-Term Sustainability

Although water is considered a human right, rural communities in many countries face challenges related to the lack of a safe water supply. In rural areas, where there is no access to public or private water supply, populations have no other choice than to rely on other unsafe sources of water. Community-managed water supply (CMWS) has emerged as an alternative to address the lack of access to safe water. Nonetheless, this alternative has several critical characteristics that harm the sustainability of water supplies. Studies on sustainability and the long-term impact of the CMWS were explored through a review of recent literature using Scopus and Web of Science databases, which analyzed 86 papers reporting on research into the sustainability and efficiency of water supply systems managed and operated by local communities, as well as the long-term critical factors that can interfere with the functionality of these systems. Based on the critical factors most cited in the literature, we proposed a framework of strategies that interrelate and integrate the critical factors into levels of responsibility. The most critical factors are related to the community level, such as inadequate capacity and ineffective systems. This demonstrates the relevance of local characteristics in the implementation of water management systems. The most cited sustainability strategies refer to the local level as the one requiring action to promote effective community involvement and post-construction support. The framework helps to conceptualize what we called an enabling environment for decision-making, and thus, the achievement of the long-term sustainability of water supply.

Prevalence and risk factors of Neospora caninum and Toxoplasma gondii infection in breeding ewes from central western Mexico.

The objective of the study was to analyse the prevalence of infection by N. caninum and T. gondii in breeding ewes from central western Mexico. For this purpose, 184 blood samples were collected from sheep in the reproductive stage, which were analysed by ELISA and PCR tests, respectively, and the association between seroprevalence and some management factors was estimated by means of a logistic regression analysis. For N. caninum, a seroprevalence of 15.22% was identified, while the DNA detection in blood was 14.13% (26/184); positive animals were found in 75% of the farms (6/8). The variables poor placental waste management (OR 8.4), abortion history (OR 1.5) and presence of rodents (OR 1.3) were identified as risk factors for N. caninum infection. In the case of T. gondii, a seroprevalence of 61.96% was found, and antibodies were detected in eight farms included in the study; no positive samples were identified for T. gondii by the PCR test. The main identified risk factors for T. gondii were as follows: poor hygiene conditions (OR 12.5), presence of cats (OR 9.5), presence of other domestic animals (OR 5.7), urban context of the farm (OR 9.5) and public water supply (OR 5.3). The seroprevalence of co-infection of T. gondii and N. caninum in breeding ewes was 7% (13/184; 95% CI 6.92-7.20). T. gondii has a high seroprevalence while N. caninum was of lower proportion, and both may be associated with reproductive losses for these herds studied.

Blockchain Empowered Smart Home: A Scalable Architecture for Sustainable Smart Cities

Emerging growth in technology has rapidly changed our homes and cities. Present homes and cities will be upgraded to smart homes and smart cities in the near future. Various solutions used to build the smart-city network demand a scalable and decentralized solution. This study proposes a blockchain-empowered decentralized and scalable solution for a sustainable smart-city network. The Internet of Things (IoT), fog nodes, permissioned trust chain, smart contract, blockchain, and InterPlanetary file system (IPFS) are deployed to construct a scalable and decentralized solution for a sustainable smart city. Three main public sector departments, i.e., electricity, water supply, and health care, are studied over the proposed solution. The proposed solution is implemented over constrained application protocol (CoAP) and Ethereum blockchain. The performance of the proposed model is evaluated for 1500 devices and over 10,000 records. A total 77.44% improvement is registered during performance evaluation over a scalable environment. The performance evaluation of each case study and collaborative performance evaluation concludes the improvised performance of the proposed solution for scalable and distributed applications. Better performance, scalability, and the distributed nature of the presented model make it suitable for the sustainable smart-city network.

Cyanotoxins and water quality parameters as risk assessment indicators for aquatic life in reservoirs

We assessed the extent of pollution in an essential public water supply reservoir (southeastern Brazil). An environmental monitoring study was performed at the Billings Reservoir (at the water catchment site) to assess the water quality in 2017, 2018, and 2019. Physicochemical parameters were analyzed, quantifying the total cyanobacteria and the cyanotoxins microcystins (MCs) and saxitoxins (SXTs), as well as their possible ecological risk to the aquatic environment. We also determined metals and metalloids (As, Ba, Cd, Pb, Cu, Cr, Fe, Mn, Ni, Zn, and Sb) and fecal bacteria (Escherichia coli). Monthly samplings were performed for 2017, 2018, and 2019 (totaling 36 sampling campaigns). Metals, metalloids, and E. coli values were below the maximum limit allowed by the Brazilian legislation. High concentrations of total cyanobacteria (3.07 × 104 – 3.23 × 105 cells/mL), microcystin variants MC-LR (0.67–23.63 μg/L), MC-LA (0.03–8.66 μg/L), MC-RR (0.56–7.92 μg/L), and MC-YR (0.04–1.24 μg/L), as well as the saxitoxins GTX2 (0.18–5.37 μg/L), GTX3 (0.13–4.40 μg/L), and STX (0.12–2.92 μg/L) were detected. From an ecotoxicological point of view, the estimated values for the risk quotient (RQ) for microcystins and saxitoxins were largely greater than 1, indicating a high risk to aquatic life. Therefore, further efforts need to be made to delay the eutrophication of the reservoir.

Chlorination for low-cost household water disinfection - A critical review and status in three Latin American countries.

Chlorination has historically provided microbiologically safe drinking water in public water supplies. Likewise, chlorine has also been introduced as a low-cost disinfection method in rural and marginalized communities, both at community and household level, as well as during emergencies. Although this practice is common and well established for use as a household water treatment technology in the Global South, several challenges in effective and efficient implementation still need to be addressed. Here, we explored these issues by a literature review and narrowed them to the status of three Latin American countries (Mexico, Colombia, and Brazil). Overall, it was found that although guidance on household-based chlorination includes information on health risks and hygiene, this may not create enough incentive for the user to adapt the method satisfactorily. Physicochemical quality of the water influences chlorination efficiency and it is found that variations in quality are rarely considered when recommending chlorine doses during implementation. These are far more often based on a few measurements of turbidity, thereby not considering dissolved organic matter, or seasonal and day-to-day variations. Other factors such as user preferences, chlorine product quality and availability also represent potential barriers to the sustainable use of chlorination. For chlorination to become a sustainable household water treatment, more focus should therefore be given to local conditions prior to the intervention, as well as support and maintenance of behavioural changes during and after the intervention.