ARSENIC POISONING IN BANGLADESH: A GEOGRAPHIC ANALYSIS1

ABSTRACT: Drinking of arsenic‐contaminated tubewell water has become a serious health threat in Bangladesh. Arsenic contaminated tubewells are believed to be responsible for poisoning nearly two‐thirds of this country's population. If proper actions are not taken immediately, many people in Bangladesh will die from arsenic poisoning in just a few years. Causes and consequences of arsenic poisoning, the extent of area affected by it, and local knowledge and beliefs about the arsenic problem — including solutions and international responses to the problem — are analyzed. Although no one knows precisely how the arsenic is released into the ground water, several contradictory theories exist to account for its release. Initial symptoms of the poisoning consist of a dryness and throat constriction, difficulty in swallowing, and acute epigastric pain. Long‐term exposure leads to skin, lung, or bladder cancer. Both government and nongovernmental organizations (NGOs) in Bangladesh, foreign governments, and international agencies are now involved in mitigating the effects of the arsenic poisoning, as well as developing cost‐effective remedial measures that are affordable by the rural people.     

WELFARE IMPLICATIONS OF TUBEWELL IRRIGATION IN BANGLADESH1

ABSTRACT: This paper investigates and estimates the welfare loss due to monopoly in tubewell irrigation water market in Bangladesh. In this context, an attempt has been made to evaluate the efficacy of the landless irrigation groups. Using cross-sectional data and regression analysis, cost and demand functions for irrigation water are estimated. The study demonstrates the relatively superior performance of the landless groups in terms of economic efficiency in shallow tubewell irrigation operation, in comparison to irrigation operation by the landowners.     

Support services for lift irrigation in Bangladesh

The impacts of changing support systems for lift irrigation in Bangladesh from the public to the private sector are examined. Data are presented from an extensive study undertaken by IIMI and the Bangladesh Agricultural University. The results of the study clearly demonstrate that farmers, small dealers and input sellers all feel that transfer to the private sector has improved the quality of support services. As a result of the privatization of support services, more fuel is available, it is closer to the farms and there is less adulteration. A similar case holds for agricultural chemicals. In addition to improving the situation for small farmers, privatization has created thousands of jobs for small traders and repair shops. Data are presented that document the improvements in services and the expansion of small traders. The one issue that still must be solved is the future of deep tubewells, as the article documents that they are not economically vaiable without Government subsidies.     

Value of arsenic-free drinking water to rural households in Bangladesh

Using contingent valuation survey data for about 2700 households in rural Bangladesh, and applying a multinomial logit model, the paper estimates the value of arsenic-free drinking water to the rural people. The estimates indicate that the rural people in arsenic-affected areas of Bangladesh place a low value on arsenic-free drinking water. It is about 10-14 percent of the amount they are willing to pay for piped water and only about 0.2-0.3 percent of the average household income. The implication of the result is that robust but costly arsenic reduction technologies such as activated alumina technology may find little social acceptance, unless heavily subsidized.     

Pond management in rural Bangladesh: problems and possibilities in the context of the water supply crisis

Today, Bangladesh is confronted with an immense water supply crisis: the decline of surface water bodies as well as a fall in the water table, together with the multiple pollution of the water in general, has put pressure on a precious resource that needs to meet the demand of a growing population. However, the most serious problem became public just four years ago—the contamination of the groundwater with arsenic. Considering the extent of the water supply problem, solutions for the future provision of safe drinking water are urgently needed. This article argues that ponds, a traditional water source in Bangladesh, could contribute to a solution. However, it is essential to recognise the problems and advantages of ponds in order to make suggestions on how to integrate ponds into the national water policy. Therefore, this paper analyses pond management—the use, maintenance and control of ponds—and its change from the past to the present. A holistic, dynamic and actor-oriented approach on a small scale was proved to be the appropriate instrument for this analysis.     

STATISTICAL ANALYSIS OF WATER CONSUMPTION1

The purpose of this study was to determine the degree of influence of various factors on municipal water consumption in Illinois. For the collection of basic data, questionnaires were sent to all public water works of incorporated towns. The questionnaire was designed to obtain information on factors which may have any effect on water use. The effects of the different parameters on water consumption were based on several correlation and regression combinations of predictands and predictors. It was found that in the Chicago region the percent of services and water used for commercial and industrial purposes and the age of the water works were the most important parameters influencing water consumption (gallons per capita per day) when pumpage is metered at the water works as well as at the customers. For the State, excluding the Chicago region, percent of public water use, persons per service, population and commercial and industrial water use were the most important parameters. It has been recommended that similar statistical analysis be conducted periodically to establish a trend or law of change from the influencing parameters.     

Diversion of the Ganges Water at Farakka and Its Effects on Salinity in Bangladesh

/ The Ganges River supplies water to the southwest region of Bangladesh mainly through one of its distributaries-the Gorai River. India commissioned a barrage on the Ganges River at Farakka in April 1975 to divert water and make the Bhagirathi-Hooghly River navigable. The diversion has reduced the dry season discharge of the Ganges and Gorai rivers in Bangladesh. Statistical analyses indicate that the changes in the dry season discharge of these rivers are significant. Reduced discharge in the Gorai River has induced accelerated sedimentation and increased salinity in the southwest region of Bangladesh. Empirical analyses demonstrate the relationship between discharge in the Gorai River and salinity. Analyses also determine the requirement of flow for the Ganges and Gorai rivers to keep salinity at threshold limits. Increased salinity has caused negative effects on agriculture, forestry, industry, and drinking water in the southwest region of Bangladesh.KEY WORDS: Bangladesh; Ganges River; Gorai River; Farakka diversion; Salinity     

Review of socio-economic drivers of community acceptance and adoption of decentralised water systems

The aim of this paper is to highlight key social and economic drivers crucial to understanding community acceptance and adoption of decentralised water systems. The review focused on social science literature pertaining to alternative forms of household water, with an emphasis on research examining decentralised water acceptance. Researchers consistently reported that most communities were open to alternative water sources for domestic applications; however, this was highly dependent upon the level of personal contact with the water. Acceptance and adoption of alternative water technology, such as decentralised systems, was influenced by risk perception, water culture, and threat perception. Motivational drivers were also identified as potentially influencing adoption of decentralised systems. A clear limitation of the literature was found to be an over-reliance on measuring people's intentions to adopt alternative water systems and building a conceptual understanding of acceptance solely on hypothetical water supply scenarios. Further, within the social science literature there appears to be a skewing towards focusing on acceptance of centralised alternative water, such as recycled and desalinated water systems. Although there are some research outcomes that are generalizable to the decentralised water context, it is clear that there is a significant gap in the knowledge base of social drivers specific to the acceptance of decentralised water systems and the factors contributing to its widespread use. It is recommended that future research focus on examining public attitudes relevant to decentralised water systems, as well as adoption behaviours among current users of these systems. This will assist in developing policies specific to domestic decentralised water use.     

饮用水中砷去除技术综述

自从1996年孟加拉国和印度报道慢性砷中毒事件以来,饮用水砷污染和砷中毒问题就受到全世界的关注。如何解决这一难题,研究人员进行了大量研究。本文综述了饮用水中砷的去除方法,包括混凝／沉淀、吸附、离子交换技术等,对各种除砷技术进行了总结和比较。     

INFLUENCES OF WATERSHED URBANIZATION AND INSTREAM HABITAT ON MACROINVERTEBRATES IN COLD WATER STREAMS1

ABSTRACT: We analyzed data from riffle and snag habitats for 39 small cold water streams with different levels of watershed urbanization in Wisconsin and Minnesota to evaluate the influences of urban land use and instream habitat on macroinvertebrate communities. Multivariate analysis indicated that stream temperature and amount of urban land use in the watersheds were the most influential factors determining macroinvertebrate assemblages. The amount of watershed urbanization was nonlinearly and negatively correlated with percentages of Ephemeroptera‐Plecoptera‐Trichoptera (EPT) abundance, EPT taxa, filterers, and scrapers and positively correlated with Hilsenhoff biotic index. High quality macroinvertebrate index values were possible if effective imperviousness was less than 7 percent of the watershed area. Beyond this level of imperviousness, index values tended to be consistently poor. Land uses in the riparian area were equal or more influential relative to land use elsewhere in the watershed, although riparian area consisted of only a small portion of the entire watershed area. Our study implies that it is extremely important to restrict watershed impervious land use and protect stream riparian areas for reducing human degradation on stream quality in low level urbanizing watersheds. Stream temperature may be one of the major factors through which human activities degrade cold‐water streams, and management efforts that can maintain a natural thermal regime will help preserve stream quality.     

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.     

Potential fresh water saving using greywater in toilet flushing in Syria

Greywater reuse is becoming an increasingly important factor for potable water saving in many countries. Syria is one of the most water scarce countries in the Middle East. However, greywater reuse is still not common in the country. Regulations and standards for greywater reuse are not available. Recently, however, several stakeholders have started to plan for greywater reuse. The main objective of this paper is to evaluate the potential for potable water saving by using greywater for toilet flushing in a typical Syrian city. The Sweida city in the southern part of Syria was chosen for this purpose. Interviews were made in order to reflect the social acceptance, water consumption, and the percentage of different indoor water uses. An artificial wetland (AW) and a commercial bio filter (CBF) were proposed to treat the greywater, and an economic analysis was performed for the treatment system. Results show that using treated greywater for toilet flushing would save about 35% of the drinking water. The economic analyses of the two proposed systems showed that, in the current water tariff, the payback period for AW and CBF in block systems is 7 and 52 years, respectively. However, this period will reduce to 3 and 21 years, respectively, if full water costs are paid by beneficiaries. Hence, introducing artificial wetlands in order to make greywater use efficient appears to be a viable alternative to save potable water.     

When sustainable may not mean just: a critical interpretation of urban water consumption decline in Barcelona

In this paper, we document and analyse the recent decline (2007–2013) in domestic water consumption in Barcelona. The postulates of ecological modernisation and market environmentalism celebrate these declines as an example of sustainable development, thanks to the combination of more efficient technologies and economic incentives. However, these interpretations ignore the new framework of social relations introduced by technologies and markets and take environmental improvements as homogeneous and universal regardless of distributional issues. Therefore, it would be perfectly possible to achieve optimal environmental situations in the context of deteriorating social conditions, particularly in terms of access to basic resources by the most disadvantaged. We explored the relationships between declining domestic water consumption and the uneven impact of the economic crisis on Barcelona’s urban geography. We found that the alleged increase in environmental sustainability that follows decline in resource use translates into highly uneven social impacts in terms of both accessibility and consumption. These results show that water flows have profound political dimensions and that water justice in terms of distributional costs and benefits but also in terms of recognition and participation of the less well-off should be a fundamental component of future urban water policies in this area.     

IMPLICATIONS OF ON‐GROUND NITROGEN LOADING AND SOIL TRANSFORMATIONS ON GROUND WATER QUALITY MANAGEMENT1

ABSTRACT: This paper presents a modeling approach based on a geographic information system (GIS) to estimate the variability of on‐ground nitrogen loading and the corresponding nitrate leaching to ground water. The methodology integrates all point and nonpoint sources of nitrogen, the national land cover database, soil nitrogen transformations, and the uncertainty of key soil and land use‐related parameters to predict the nitrate mass leaching to ground water. The analysis considered 21 different land use classes with information derived from nitrogen sources such as fertilizer and dairy manure applications, dairy lagoons, septic systems, and dry and wet depositions. Simulations were performed at a temporal resolution of one month to capture seasonal trends. The model was applied to a large aquifer of 376 square miles in Washington State that serves more than 100,000 residents with drinking water. The results showed that dairy manure is the main source of nitrogen in the area followed by fertilizers. It was also seen that nitrate leaching is controlled by the recharge rate, and there can be a substantial buildup of soil nitrogen over long periods of time. Uncertainty analysis showed that denitrification rate is the most influential parameter on nitrate leaching. The results showed that combining management alternatives is a successful strategy, especially with the use of nitrification inhibitors. Also, change in the land use pattern has a noticeable impact on nitrate leaching.     

Impact of Human Activities on Carbon Dioxide (CO<Subscript>2</Subscript>) Emissions: A Statistical Analysis

Summary The balance of evidence suggests a perceptible human influence on global ecosystems. Human activities are affecting the global ecosystem, some directly and some indirectly. If researchers could clarify the extent to which specific human activities affect global ecosystems, they would be in a much better position to suggest strategies for mitigating against the worst disturbances. Sophisticated statistical analysis can help in interpreting the influence of specific human activities on global ecosystems more carefully. This study aims at identifying significant or influential human activities (i.e. factors) on CO₂ emissions using statistical analyses. The study was conducted for two cases: (i) developed countries and (ii) developing countries. In developed countries, this study identified three influential human activities for CO₂ emissions: (i) combustion of fossil fuels, (ii) population pressure on natural and terrestrial ecosystems, and (iii) land use change. In developing countries, the significant human activities causing an upsurge of CO₂ emissions are: (i) combustion of fossil fuels, (ii) terrestrial ecosystem strength and (iii) land use change. Among these factors, combustion of fossil fuels is the most influential human activity for CO₂ emissions both in developed and developing countries. Regression analysis based on the factor scores indicated that combustion of fossil fuels has significant positive influence on CO₂ emissions in both developed and developing countries. Terrestrial ecosystem strength has a significant negative influence on CO₂ emissions. Land use change and CO₂ emissions are positively related, although regression analysis showed that the influence of land use change on CO₂ emissions was still insignificant. It is anticipated, from the findings of this study, that CO₂ emissions can be reduced by reducing fossil-fuel consumption and switching to alternative energy sources, preserving exiting forests, planting trees on abandoned and degraded forest lands, or by planting trees by social/agroforestry on agricultural lands.     

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.     

Household water use behavior: An integrated model

Water authorities are dealing with the challenge of ensuring that there is enough water to meet demand in the face of drought, population growth and predictions of reduced supply due to climate change. In order to develop effective household demand management programs, water managers need to understand the factors that influence household water use. Following an examination and re-analysis of current water consumption behavioral models we propose a new model for understanding household water consumption. We argue that trust plays a role in household water consumption, since people will not save water if they feel others are not minimizing their water use (inter-personal trust). Furthermore, people are less likely to save water if they do not trust the water authority (institutional trust). This paper proposes that to fully understand the factors involved in determining household water use the impact of trust on water consumption needs investigation.     

地表水水源地突发水污染风险评价方法现状

饮用水水源地与人民的生命安全和社会经济的稳定发展联系非常密切,突发水污染事故严重威胁着水源地饮用水安全。突发水污染事故具有不确定性和模糊性,对不同类型的水源地影响侧重点不同;引发突发水污染事故的因素可以分为人为因素和非人为因素,突发水污染事故多为人为因素所引发;评价方法分为3种类型,分析了分别适用于大尺度河流型的体系构建法和小尺度湖库型的模型模拟法,指出体系构建法综合宏观的特点,以及模型模拟法微观量化的评价方式,综合评价法则结合了这2种方法的优点;分析了评价方法的不足并对发展趋势做出展望,以期为水源地保护工作者提供对水源地突发水污染事故选择评价方法的思路。     

湖南城乡居民虚拟水消费结构及其用水效率评价

运用水足迹方法,根据2000—2008年的统计资料,对湖南省城乡居民虚拟水消费结构和城乡居民用水效率进行综合评价。结果表明,近年来湖南省总水足迹和人均水足迹均呈下降趋势;城镇居民虚拟水消费结构多样性指数值高于农村,城镇居民消费观念和消费模式更为合理;虚拟水消费结构多样性指数整体呈上升趋势,居民消费结构逐渐转向多元化;社会水资源稀缺指数不高,水资源利用还有较大空间,利用效率有了明显提高。     

农村水源地水质重金属健康风险评估研究

介绍了饮用水水源地中基因毒物质和躯体毒物质所致的健康危害的风险度计算模型,并根据雅安市雨城区农村水源地水质实测资料,进行健康风险评价与分析。结果表明:(1)基因毒物质由饮水途径所致健康危害的个人年风险按大小排列为Cr(VI)>As>Cd,而躯体毒物质的个人年风险按大小排列为Hg>Pb>Mn>Fe,但前者的影响远大于后者;(2)水源地中的3种基因毒物质所致健康危害的个人年风险,远远超过瑞典环保局、荷兰建设和环境部推荐的最大可接受水平1.00×10-6a-1,且Cr(VI)的健康风险危害超过国际辐射防护委员会(ICRP)推荐的最大可接受值5.00×10-5a-1,应将Cr(VI)视为本区饮水的优先治理污染物。