Community Perception of Water Quality in a Mining-Affected Area: A Case Study for the Certej Catchment in the Apuseni Mountains in Romania

Mining-contaminated sites and the affected communities at risk are important issues on the agenda of both researchers and policy makers, particularly in the former communist block countries in Eastern Europe. Integrated analyses and expert based assessments concerning mining affected areas are important in providing solid policy guidelines for environmental and social risk management and mitigation. Based on a survey for 103 households conducted in a former mining site in the Certej Catchment of the Apuseni Mountains, western Romania, this study assesses local communities’ perceptions on the quality of water in their living area. Logistic regression was used to examine peoples’ perception on the quality of the main river water and of the drinking water based on several predictors relating to social and economic conditions. The results from the perception analysis were then compared with the measurements of heavy metal contamination of the main river and drinking water undertaken in the same study area. The findings indicate that perception and measurement results for the water quality in the Certej Catchment are convergent, suggesting an obvious risk that mining activities pose on the surface water. However, the perception on drinking water quality was little predicted by the regression model and does not seem to be so much related to mining as to other explanatory factors, such as special mineralogy of rock and soils or improper water treatment infrastructure, facts suggested by the measurements of the contaminants. Discussion about the implications of these joint findings for risk mitigation policies completes this article.     

Influence of alkalinity, hardness and dissolved solids on drinking water taste: A case study of consumer satisfaction

Two surveys of consumer satisfaction with drinking water conducted by Taiwan Water Supply Corp. are presented in this study. The study results show that although a lot of money was invested to modify traditional treatment processes, over 60% of local residents still avoided drinking tap water. Over half of the respondents felt that sample TT (from the traditional treatment process) was not a good drinking water, whether in the first or second survey, whereas almost 60% of respondents felt that samples PA, PB, CCL and CT (from advanced treatment processes) were good to drink. For all drinking water samples, respondent satisfaction with a sample primarily depended on it having no unpleasant flavors. Taiwan Environmental Protection Administration plans to revise the drinking water quality standards for TH and TDS in the near future. The new standards require a lower TH concentration (from currently 400mg/L (as CaCO(3)) to 150mg/L (as CaCO(3))), and a lower TDS maximum admissible concentration from the current guideline of 600 to 250mg/L. Therefore, this study also evaluated the impacts on drinking water tastes caused by variations in TH and TDS concentrations, and assessed the need to issue more strict drinking water quality standards for TH and TDS. The research results showed that most respondents could not tell the difference in water taste among water samples with different TDS, TH and alkalinity. Furthermore, hardness was found to be inversely associated with cardiovascular diseases and cancers, and complying with more strict standards would lead most water facilities to invest billions of dollars to upgrade their treatment processes. Consequently, in terms of drinking water tastes alone, this study suggested that Taiwan Environmental Protection Administration should conduct more thorough reviews of the scientific literature that provides the rationale for setting standards and reconsider if it is necessary to revise drinking water quality standards for TH and TDS.     

Uncertainty modelling in multi-criteria analysis of water safety measures

Water utilities must assess risks and make decisions on safety measures in order to obtain a safe and sustainable drinking water supply. The World Health Organization emphasises preparation of water safety plans, in which risk ranking by means of risk matrices with discretised probability and consequence scales is commonly used. Risk ranking enables prioritisation of risks, but there is currently no common and structured way of performing uncertainty analysis and using risk ranking for evaluating and comparing water safety measures. To enable a proper prioritisation of safety measures and an efficient use of available resources for risk reduction, two alternative models linking risk ranking and multi-criteria decision analysis (MCDA) are presented and evaluated. The two models specifically enable uncertainty modelling in MCDA, and they differ in terms of how uncertainties in risk levels are considered. The need of formal handling of risk and uncertainty in MCDA is emphasised in the literature, and the suggested models provide innovations that are not dependent on the application domain. In the case study application presented here, possible safety measures are evaluated based on the benefit of estimated risk reduction, the cost of implementation and the probability of not achieving an acceptable risk level. Additional criteria such as environmental impact and consumer trust may also be included when applying the models. The case study shows how safety measures can be ranked based on preference scores or cost-effectiveness and how measures not reducing the risk enough can be identified and disqualified. Furthermore, the probability of each safety measure being ranked highest can be calculated. The two models provide a stepwise procedure for prioritising safety measures and enable a formalised handling of uncertainties in input data and results.     

Drinking water risk assessment in practice: the case of Swedish drinking water producers at risk from floods

To achieve a safe and reliable drinking water supply, water producers need to manage a large range of risks regarding both water quality and quantity. A risk management approach where risks are systematically identified and handled in a preventive manner is promoted by the World Health Organization and supported by researchers and drinking water experts worldwide. Risk assessment is an important part of such a management approach, and a variety of tools for risk assessment are described in the literature. There is, however, little knowledge of how drinking water risk assessment is performed in practice, including which tools that are actually used. This study investigates the use of risk assessment tools, and the approach to risk management, on a local level in the Swedish water sector. It is based on interviews with key persons from a targeted selection of water producers. We find that the application of tools as well as the approach to risk assessment and management differs considerably between the water producers. The tools most frequently used are mainly the ones promoted or required by Swedish national organizations. Although many of the water producers have done some kind of risk assessment, most have not implemented a risk management approach. Furthermore, their knowledge of the concepts of risk and risk management is often limited. The largest challenge identified is to prioritize risk assessment, so that it is actually performed and then used as a basis for managing risk in a systematic way.     

Spatial variations of human health risk associated with exposure to chlorination by-products occurring in drinking water

During disinfection, chlorine reacts with organic matter present in drinking water and forms various undesirable chlorinated by-products (CBPs). This paper describes a study of the spatial variability of human health risk (i.e., cancer effects) from CBP exposure through drinking water in a specific region. The region under study involves nine drinking water distribution systems divided into several zones based on their characteristics. The spatial distribution of cancer risk (CR) was estimated using two years of data (2006-2008) on various CBP species. In this analysis, trihalomethanes (THMs) and haloacetic acids (HAAs) served as surrogates for CBPs. Three possible routes of exposure (i.e., via ingestion, inhalation and dermal contact) were considered for each selected compound. The cancer risk assessment involved estimating a unit risk (R(T)) in each zone of the selected distribution systems. A probabilistic analysis based on Monte Carlo simulations was employed. Risk assessment results showed that cancer risk varied between systems, but also within individual systems. As a result, the population of the same region was not exposed to the same risk associated with CBPs in drinking water. Unacceptable levels (i.e., R(T) > 10(-4)) for the estimated CR were determined for several zones in the studied region. This study demonstrates that a spatial-based analysis performed to represent the spatial distribution of risk estimates can be helpful in identifying suitable risk management strategies. Suggestions for improving the risk analysis procedure are also presented.     

Unsafe waters: the hydrosocial cycle of drinking water in Western Mexico

ABSTRACT

Mexico faces multiple water quality challenges, both in terms of the water supplied to the population as well as surface and underground water sources. Problems with drinking water supply affect the population in diverse ways, from associated health risks to high levels of intermittency in service to the poor perception of the quality of piped water – leading to high levels of bottled water consumption. In this text we explore the issue of drinking water quality in three contexts in the state of Jalisco: in Guadalajara, the state’s main urban area, in the peri-urban municipality of El Salto, and in the mid-sized city of San Juan de los Lagos. Our analysis explores drinking water regulations, the water quality monitoring undertaken by state and local authorities, access to information, as well as the actions and perceptions of water service providers. Looking at cases of indirect reuse of wastewater as well as groundwater sources with high levels of fluoride and arsenic, we argue that the foregrounding of water quality is key to illuminating social inequalities in access to water and in teasing out power relations prevailing in current hydrosocial regimes. We conclude that this hydrosocial cycle of drinking water is characterised by prioritising access to water for economic actors, facilitated by lax regulations and minimal enforcement, as well as by the systematic neglect by government authorities at all levels of the protection of watersheds and aquifers, and of water quality issues generally.     

Cost-benefit analysis of central softening for production of drinking water

Softening drinking water before distribution yields advantages with environmental impact, such as lower household products consumption, less scaling in piping and machines, and the avoidance of decentralized, domestic softeners. Central softening is under consideration in Flanders by the largest water supplier, VMW (Dutch acronym for “Flemish Company for Water Supply”), to deliver soft (15 °F) water to their customers. A case study is presented for a region with hard water (47 °F). The chosen technique is the pellet reactor, based on precipitation of CaCO₃ by NaOH addition. This softening operation has possibly large impact on the environment and the water consumption pattern.A cost-benefit analysis has been made to estimate the added value of central softening, by investigating the impact on the drinking water company, on their customers, on employment, on environment, on health, etc. The analysis for the region of study revealed benefits for customers which were higher than the costs for the drinking water company. However, pricing of drinking water remains an important problem.A sensitivity analysis of these results has also been made, to evaluate the impact of important hypothesis, and to be able to expand this study to other regions. The conclusions for this part show that softening is beneficial if water hardness is to be decreased by at least 5 °F.     

Development of performance indicators for small Quebec drinking water utilities

This study presents a comparative performance analysis of small drinking water utilities in Quebec (Canada). The investigation bears on 10 utilities that use surface water or groundwater under the direct influence of runoff and apply chlorination as the only treatment before distribution. The utilities under study were divided into two groups: four utilities that had never or rarely provided water violating provincial drinking water microbiological standards (relating to fecal and/or total coliform bacteria), called nonproblematic utilities, and six utilities that quite often violated the standards, designated as problematic utilities. The objective of the study is to develop utility performance indicators capable of explaining current and historical distributed water quality. Indicators are based on operational, infrastructure, and maintenance characteristics of utilities that are integrated using a multivariable weight-based index. Results show that utility performance indicators are systematically better for the nonproblematic group of utilities as compared to the problematic group. Disinfection-related, infrastructure, and maintenance variables are those that most contributed to indicator values. Sensitivity analyses served to assess the impact on indicator results of excluding variables and changing their weights.     

Evaluation of the vulnerability to contamination of drinking water systems for rural regions in Québec,Canada

The aim of this paper is to describe a method for evaluating the vulnerability of drinking water systems to contamination, in particular in rural regions used intensively for agriculture. To do so, various indicators were developed to represent the source to tap multi-barrier approach for drinking water safety. These indicators correspond to four barriers: source susceptibility to contamination; water treatment efficiency; distribution system management; and, overall management of water quality. The indicators were classified, regrouped and weighted within a model based on a multi-criteria analysis. The method was developed and applied to 39 municipal water systems of rural Quebec, Canada. The model obtained can be used for planning purposes to prioritise water systems requiring improvements.     

Water distribution system failure: a framework for forensic analysis

The main purpose of a water distribution system (WDS) is to deliver safe water of desirable quality, quantity and continuity to consumers. However, in many cases, a WDS fails to fulfill its goal owing to structural and associated hydraulic failures and/or water quality failures. The impact of these failures can be reduced significantly if preventive actions are taken based on their potential of occurrences or if a failure occurs and is detected within a minimum period of time after its occurrence. The aim of this research was to develop a forensic system for WDS failures. As part of the proposed forensic analysis, a framework has been developed, which investigates structural and associated hydraulic failures as well as water quality failures and integrates all failure investigation under a single platform. Under this framework, four different models have been developed to evaluate and identify structural and associated hydraulic failures and water quality failures. If a failure is detected in the system, the framework is capable of identifying the most probable location of the failure. To investigate the effectiveness of the proposed framework, the developed models have been tested and implemented in different WDSs.     

Establishing components of community satisfaction with recycled water use through a structural equation model

The use of recycled water is being promoted through policy in many parts of the world with the aim of achieving sustainable water management. However there are some major barriers to the success of recycled water use policies and their instruments, in particular for potable reuse schemes. One of these barriers can be a lack of community support. Despite the critical nature of community attitudes to recycled water to the success of projects, they are often little understood. Further information is required to ensure the successful implementation of recycled water policy and to ensure sustainable management of water resources is achieved. The aim of this paper is to establish the key components of community satisfaction with recycled water. This was investigated through a case study of the Mawson Lakes population in South Australia, where recycled water is used for non-potable purposes through a dual water supply system (the 'recycled water system'). This paper reports results from a survey of 162 Mawson Lakes residents. A structural equation model (SEM) was developed and tested to explain and predict components of community satisfaction with recycled water use (for non-potable use) through the dual water supply system. Results indicate the components of satisfaction with recycled water use were an individual's positive perception of: the Water Authority's communication, trust in the Water Authority, fairness in the recycled water system's implementation, quality of the recycled water, financial value of the recycled water system, and risk associated with recycled water use (negative relationship). The results of this study have positive implications for the future management and implementation of recycled water projects in particular through dual water supply systems. The results indicate to water authorities and water policy developers guiding principles for community consultation with regards to the management of recycled water projects.     

嘉陵江下游饮用水氟化物时空变异特征研究

饮用水中可溶性氟化物是公众摄入氟的主要途径,其含量水平影响人体健康。分别于2015~2017年的丰水期和枯水期6次随机采集监测了嘉陵江下游52个饮用水样中氟化物含量,并基于地理信息系统平台和健康风险指数法进行了评价。结果表明,该区域饮用水中氟化物浓度平均为0.20~0.25 mg/L。除2015年部分样点外,其余样点的氟浓度均低于国家标准限值。其年际变化为2015年明显高于2016年和2017年(P<0.05);年内变化为枯水期略高于丰水期。研究表明,研究区饮用水中氟化物不会对人体造成威胁,且有逐年降低的趋势,建议当地居民适当增加氟的摄入量,以降低患龋齿的风险。     

ARE RURAL RESIDENTS WILLING TO PAY ENOUGH TO IMPROVE DRINKING WATER QUALITY?1

ABSTRACT: The concentrations of iron and sulfate in community water supplies are a concern for a number of areas in southwestern Minnesota. This study used the contingent valuation method to determine how much consumers would be willing to pay to improve their drinking water quality. On average, individuals were willing to pay US$5.25 per month (in 1995 U.S. dollars) to reduce the level of iron and US$4.33 per month to reduce the level of sulfate in their water to the USEPA's secondary standards for drinking water quality. Respondents with negative perceptions of their drinking water quality were willing to pay more to improve water quality. The aggregate annual willingness to pay (WTP) for all consumers in community water systems in southwestern Minnesota that were out of compliance with water quality standards were estimated to be US$2.4 million and US$2.0 million (in 1995 dollars) for reducing the levels of iron and sulfate, respectively. Yet the total WTP of consumers who use small community water systems may not be enough to pay the full cost of providing improved water in those systems. Economies of scale in water treatment and difficulties in financing improvements mean that technical innovation, government assistance, or institutional changes may be needed to improve water quality in these areas.     

Adaptive management for mitigating Cryptosporidium risk in source water: A case study in an agricultural catchment in South Australia

Water-borne pathogens such as Cryptosporidium pose a significant human health risk and catchments provide the first critical pollution ‘barrier’ in mitigating risk in drinking water supply. In this paper we apply an adaptive management framework to mitigating Cryptosporidium risk in source water using a case study of the Myponga catchment in South Australia. Firstly, we evaluated the effectiveness of past water quality management programs in relation to the adoption of practices by landholders using a socio-economic survey of land use and management in the catchment. The impact of past management on the mitigation of Cryptosporidium risk in source water was also evaluated based on analysis of water quality monitoring data. Quantitative risk assessment was used in planning the next round of management in the adaptive cycle. Specifically, a pathogen budget model was used to identify the major remaining sources of Cryptosporidium in the catchment and estimate the mitigation impact of 30 alternative catchment management scenarios. Survey results show that earlier programs have resulted in the comprehensive adoption of best management practices by dairy farmers including exclusion of stock from watercourses and effluent management from 2000 to 2007. Whilst median Cryptosporidium concentrations in source water have decreased since 2004 they remain above target levels and put pressure on other barriers to mitigate risk, particularly the treatment plant. Non-dairy calves were identified as the major remaining source of Cryptosporidium in the Myponga catchment. The restriction of watercourse access of non-dairy calves could achieve a further reduction in Cryptosporidium export to the Myponga reservoir of around 90% from current levels. The adaptive management framework applied in this study was useful in guiding learning from past management, and in analysing, planning and refocussing the next round of catchment management strategies to achieve water quality targets.     

The real water consumption behind drinking water: the case of Italy

The real amount of drinking water available per capita is a topic of great interest for human health and the economic and political management of resources. The global market of bottled drinking water, for instance, has shown exponential growth in the last twenty years, mainly due to reductions in production costs and investment in promotion. This paper aims to evaluate how much freshwater is actually consumed when water is drunk in Italy, which can be considered a mature bottled-water market. A Water Footprint (WF) calculation was used to compare the alternatives: bottled and tap water. Six Italian brands of water sold in PET bottles were inventoried, analysed and compared with the public tap water of the city of Siena, as representative of the Italian context. Results showed that more than 3 L of water were needed to provide consumers with 1.50 L of drinking water. In particular, a volume of 1.50 L of PET-bottled water required an extra virtual volume of 1.93 L of water while an extra 2.13 L was necessary to supply the same volume of tap water. These values had very different composition and origin. The WF of tap water was mainly due to losses of water during pipeline distribution and usage, while WF of bottled water was greatly influenced by the production of plastic materials. When the contribution of cooling water was added to the calculation, the WF of bottled water rose from 3.43 to 6.92 L. Different strategies to reduce total water footprint are discussed.     

Relative cancer risks of chemical contaminants in the great lakes

Anyone who drinks water or eats fish from the Great Lakes consumes potentially carcinogenic chemicals. In choosing how to respond to such pollution, it is important to put the risks these contaminants pose in perspective. Based on recent measurements of carcinogens in Great Lakes fish and water, calculations of lifetime risks of cancer indicate that consumers of sport fish face cancer risks from Great Lakes contaminants that are several orders of magnitude higher than the risks posed by drinking Great Lakes water. But drinking urban groundwater and breathing urban air may be as hazardous as frequent consumption of sport fish from the Great Lakes. Making such comparisons is difficult because of variation in types and quality of information available and in the methods for estimating risk. Much uncertainty pervades the risk assessment process in such areas as estimating carcinogenic potency and human exposure to contaminants. If risk assessment is to be made more useful, it is important to quantify this uncertainty.     

Privatization and Europeanization: The Changing Context of Water Supply in Britain and France

This paper examines changes in the provision of water services, and in particular drinking water supply, in two Member States of the European Union, Britain England and Wales and France, by considering the impact of the twin processes of water service privatization and the Europeanization of environmental regulatory regimes. The paper demonstrates that in two nations with very different water service traditions, the articulation of these processes has led to profound shifts not only in management style but also in the perception of drinking water supply as a service to consumers. The British and French models are compared as are their responses to these twin processes. It is argued that while the British model has proved more responsive to the exigencies of European Union environmentalstandards,this has been at the expense of public confidence. In France, the existence of a well established traditional management style is, potentially, under greater long term threat from the growth of private water companies and the increasing importance of European legislation.     

Understanding stewardship behaviour: factors facilitating and constraining private water well stewardship

Regulatory frameworks to ensure municipal drinking water safety exist in most North American jurisdictions. However, similar protection is rarely provided to people reliant on water provided from private wells. In Canada, approximately 4 million people depend on privately owned, domestic wells for their drinking water. Numerous studies have shown that people who rely on private wells for their water supplies are at risk from nitrate and bacterial contamination. Given the fact that regulations relating to private wells tend to be weak or poorly enforced, actions taken by well owners to protect their own drinking water safety are extremely important. Drawing on one of the largest and most comprehensive surveys of private well owners ever conducted in Canada or elsewhere, this paper explores factors that influence well owner stewardship behaviour. Key behaviours examined included annual testing of well water and inspection of wells, measures to protect water quality, and proper decommissioning of unused wells. A geographically-stratified survey, sent to 4950 well owners in Ontario, Canada, resulted in an effective response rate of 34% (n = 1567). Logistic regression analyses revealed that motivations for well stewardship behaviours included reassurance, the perception of problems, and knowledge of the environment. Knowing how to perform stewardship behaviours was an important antecedent to action. Barriers to stewardship included complacency, inconvenience, ignorance, cost, and privacy concerns. To promote stewardship, local initiatives, better educational materials, and enforcement through real estate laws are all required. Ultimately, drinking water safety for people reliant on private wells is shown to be a responsibility shared by governments and private well owners.     

Water quality indices appraisal and health risk assessment of nitrate,mercury and lead in water distribution network: A case study of Robat Karim in Tehran,Iran

Groundwater is a basic source of drinking water supply for urban and rural areas. This is especially the case for communities located in arid and semi-arid regions that rely on groundwater for drinking purposes. The present study set out to assess the potential health impacts of water impurities and to investigate the qualitative status of drinking water in Robat Karim rural areas, located in southwest Tehran, Iran. A total of 66 samples were collected from the water distribution network of 11 villages (33 sampling points, on two occasions) during September 2020 and were tested in terms of the most common quality parameters such as pH, mercury (Hg), lead (Pb), copper (Cu), zinc (Zn), chloride (Cl^–), chlorate (ClO₃^–), nitrite (NO₂^–), nitrate (NO₃^–), and flouride (F^–). Multiple methods and indexes including water quality index (WQI), hazard quotient (HQ), and hazard index (HI), were worked out to assess the quality of water and health risk assessment of NO₃^– Pb²⁺ and Hg²⁺. The results revealed that 33% and 90% of sampling sites have significantly high nitrate and total hardness (TH) concentrations, exceeding the maximum permissible limits set by World Health Organization (WHO; 50 and 200 mg/L, respectively). Furthermore, five sampling points exhibited poor WQIs mainly related to NO₃^– and TH. HQ values higher than 1 for nitrate were noticed in most sampling locations. Except for one sampling point, the HQ obtained for Pb²⁺ and Hg²⁺ were below 1 indicating no obvious health hazard. This study represents that children and infants are at higher risk of chronic toxicity by excess NO₃^– intake. The health hazard that is yet imposed on the community by NO₃^– necessitates regular monitoring of drinking water, the use of advanced technologies to purify water or otherwise alternative resources should be proposed.