Non-agglutinating cholera-like Vibrios in sewage,surface water and sea water

Routine bacteriological analysis of sewage work effluents and surface waters has not revealed evidence of Vibrio cholerae or Vibrio El Tor, whereas, non-agglutinating cholera vibrios of Heiberg's groups I and II [so-called non-agglutinating strains (NAG)] have been detected quite frequently. This frequency of NAG presence is approximately equivalent to the presence of Salmonella. Depending on local conditions, quantitative studies of equal amounts of sewage resulted in a ratio of about 1 NAG/10²Salmonella/10⁷E. coli.When it became known that NAG vibrios were capable of producing a clinical appearance in man that resembled cholera by its symptoms and severeness, NAG vibrios raised epidemiological interest. Unlike Salmonella, the nutrient requirements of NAG vibrios are moderate. The decisive factors for their persistence in the environmental are attributed to a certain chloride content in the water and an elevated pH value. Both factors are preferably present in sea water. Over a period of 3 yr, samples of water from the Baltic Sea (Lübecker Bucht) were regularly examined for the presence of NAG vibrios. During this period, there have been a number of positive findings in a sample of 100 ml water while identical samples were always Salmonella-negative.     

Managing the village-level open-access water resources in a region facing rapidly declining water availability

Growing population, human settlements, industrialization and intensification in groundwater-based cultivation have resulted in severe onslaught on underground aquifers in West Bengal, an eastern province of India with high population density. The present paper focuses on this water resource management issue. The study shows that traditional, village-level surface water reservoirs which for centuries had supplemented irrigation in addition to providing water for all sorts of domestic needs are now in doldrums. Through statistical analysis, the study shows that for all practical purposes, there is very little effective management of these precious open-access water resources. The situation calls for paradigm shift in policy on water resource management that entails development of community-based management catalyzed by government intervention, external agencies and NGOs under supervision and control of local elected bodies.     

Natural radionuclides in bottled water in Austria

Concentration levels of 226Ra, 222Rn and 210Pb were analyzed in domestic bottled waters commercially available in Austria. Concentrations up to 0.23 Bq/l, with a geometric mean of 0.041 Bq/l were found for 226Ra. Concentrations for 222Rn ranged from <0.12-18 Bq/l, the geometric mean being 0.54 Bq/l. Lead-210 was analyzed in selected samples, the concentrations ranging from <2 to 34 mBq/l, with a geometric mean of 4.7 mBq/l. Ingestion doses resulting from consumption of these waters were calculated for the geometric mean and the maximum concentrations of the three radionuclides. The effective dose equivalents for different age groups of the population due to the intake of 226Ra range from 0.001 to 0.22 mSv/y and of 210Pb from 0.0003 to 0.05 mSv/y. Ingestion doses from 222Rn are low compared to those from 226Ra and 210Pb, ranging from 0.0001 to 0.011 mSv/y for adults and children, respectively. The doses are compared to the total ingestion dose from dietary intake of natural radionuclides on an annual basis.     

Significant issues in water resources policy

The difficulties in resolving water resource policy questions are analogous in many ways to the difficulties in resolving energy policy questions — technical, legal, institutional and social. Federal involvement in water resources began in 1809 and continues to the present time. The most recent comprehensive study was the Second National Water Assessment by the U.S. Water Resources Council in 1979. Conclusions reached were that water quality and quantity and surface and ground water are artificial distinctions, that water policies should reflect national needs and priorities, that flood control must be accelerated and drinking water quality protected and that more decisions should be made at a local level while integrated into national planning and development. Though the study disaggregated the U.S. into 106 subregions, its projections of a single future rather than a range of futures gives an erroneous sense of predictability to the work. To help resolve the major problems, inadequate supply and contamination and flooding and erosion, ultrasophisticated mathematical models are widely utilized without sufficient verification. A more tractable approach for policy studies would be to use simplified semi-empirical models rather than first principle models. Possibly more important, policy resolution awaits social value resolution which means that the policies adopted must be flexible, incremental, and non-divisive.     

The transition in Dutch water management

Over the past decades, the Dutch people have been confronted with severe water-related problems, which are the result of an unsustainable water system, arising from human interventions in the physical infrastructure of the water system and the water management style. The claims of housing, industry, infrastructure and agriculture have resulted in increasing pressure on the water system. The continuous subsidence of soil and climate change has put pressure on the land. Hence, the nature and magnitude of water-related problems have changed. Longitudinal research of relevant national policy documents reveals that the water management regime has changed its water management style over the past 30 years from a technocratic scientific style towards an integral and participatory style. We have investigated if the historical development in Dutch Water management can be characterized as a transition. Based on longitudinal research through an integrated systems analysis, document research and expert interviews, we have reconstructed the historical narrative by using the transition concepts of multi-level and multi-phase. This research indicates that the shift in Dutch Water management can be characterized as a transition. This transition is currently in the take-off stage and near the acceleration stage. This is a crucial stage as long as the considerable gap between the strategic macro-vision and the practical implementation at the micro-level remains. As long as these levels are not compatible (modulation), the transition will not be completed successfully. Transition management as multi-level governance model should therefore be adopted to facilitate the modulation.     

Radionuclide tracing of water masses and processes in the water column and sediment in the Algerian Basin

Caesium-137 and (239,240)PU were analysed in the water column along the Algerian coast. The (137)Cs activity concentration in surface water increased from the west to the east from 1.6 to 3.3 mBq L(-1), documenting a presence of Modified Atlantic Water (MAW) in the region. Higher concentrations observed in deep waters may be due to an intrusion of Levantine Intermediate Water (LIW), which has been carrying higher levels of (137)Cs from Chernobyl accident. The (239,240)Pu sub-surface concentration peaked at about 250 m water depth as a result of biogeochemical processes in the water column. The observed (239,240)Pu/(137)Cs activity ratio at the surface (0.003) was significantly lower than that in global fallout (0.04). This decrease exceeds that expected from radioactive decay of (137)Cs, and confirms that Pu due to its adsorption on sinking particles is more effectively removed from surface layers than is (137)Cs. An increase of the (239,240)Pu/(137)Cs activity ratio with depth suggests that (239,240)Pu, similarly as (137)Cs, should be also transported by advection to maintain the observed ratios in deep waters. An intrusion of LIW may enhance therefore both the (137)Cs and (239,240)Pu concentrations in deep waters. The average (238)Pu/(239+240)Pu activity ratio in seawater was 0.03+/-0.02, confirming a global fallout origin of Pu in the Algerian Basin. Caesium-137 and (239,240)Pu inventories in the water column were estimated to be from 2.7+/-0.5 kBq m(-2) to 3.8+/-0.7 kBq m(-2), and from 13.8+/-2.6 Bq m(-2) to 41+/-7B qm(-2), respectively. The (137)Cs massic activities in surface sediment were almost constant, the average activity was 9.0+/-0.8 Bq kg(-1). Sedimentation rates obtained using the (210)Pb method were from 0.1 to 0.7 cm y(-1), and resulting penetration depths of (137)Cs in the sediment cores were from 15 to over 40 cm. The (137)Cs peaks found in the sediment cores were associated with the Chernobyl accident (1986) and global fallout (1964). The (137)Cs inventories in the sediment were increasing from the west (180 Bq m(-2)) to the east (350 Bq m(-2)).     

Impacts of climate change on surface water quality in relation to drinking water production

Besides climate change impacts on water availability and hydrological risks, the consequences on water quality is just beginning to be studied. This review aims at proposing a synthesis of the most recent existing interdisciplinary literature on the topic. After a short presentation about the role of the main factors (warming and consequences of extreme events) explaining climate change effects on water quality, the focus will be on two main points. First, the impacts on water quality of resources (rivers and lakes) modifying parameters values (physico-chemical parameters, micropollutants and biological parameters) are considered. Then, the expected impacts on drinking water production and quality of supplied water are discussed. The main conclusion which can be drawn is that a degradation trend of drinking water quality in the context of climate change leads to an increase of at risk situations related to potential health impact.     

Human health effects of residual carbon nanotubes and traditional water treatment chemicals in drinking water

The volume of industrial and domestic wastewater is increasing significantly year by year with the change in the lifestyle based on mass consumption and mass disposal brought about by the dramatic development of economies and industries. Therefore, effective advanced wastewater treatment is required because wastewater contains a variety of constituents such as particles, organic materials, and emulsion depending on the resource. However, residual chemicals that remain during the treatment of wastewaters form a variety of known and unknown by-products through reactions between the chemicals and some pollutants. Chronic exposure to these by-products or residual chemicals through the ingestion of drinking water, inhalation and dermal contact during regular indoor activities (e.g., showering, bathing, cooking) may pose cancer and non-cancer risks to human health. For example, residual aluminium salts in treated water may cause Alzheimer's disease (AD). As for carbon nanotubes (CNTs), despite their potential impacts on human health and the environment having been receiving more and more attention in the recent past, existing information on the toxicity of CNTs in drinking water is limited with many open questions. Furthermore, though general topics on the human health impacts of traditional water treatment chemicals have been studied, no comparative analysis has been done. Therefore, a qualitative comparison of the human health effects of both residual CNTs and traditional water treatment chemicals is given in this paper. In addition, it is also important to cover and compare the human health effects of CNTs to those of traditional water treatment chemicals together in one review because they are both used for water treatment and purification.     

A commentary on recent water safety initiatives in the context of water utility risk management

Over the last decade, suppliers of drinking water have recognised the limitations of relying solely on end-product monitoring to ensure safe water quality and have sought to reinforce their approach by adopting preventative strategies where risks are proactively identified, assessed and managed. This is leading to the development of water safety plans; structured 'route maps' for managing risks to water supply, from catchment to consumer taps. This paper reviews the Hazard Analysis and Critical Control Point (HACCP) procedure on which many water safety plans are based and considers its appropriateness in the context of drinking water risk management. We examine water safety plans in a broad context, looking at a variety of monitoring, optimisation and risk management initiatives that can be taken to improve drinking water safety. These are cross-compared using a simple framework that facilitates an integrated approach to water safety. Finally, we look at how risk management practices are being integrated across water companies and how this is likely to affect the future development of water safety plans.     

Photochemical behavior of mercury ore in water

The photochemical behavior of mercury ore (cinnabar) in water was studied using a blacklight lamp as a substitute of sunlight. The mercury ore was photosolubilized in water as mercuric ion, and metallic mercury was then volatilized from the aqueous suspension of mercury ore by photoirradiation. The photosolubilization of the mercury ore and the mercury volatilization were enhanced by the presence of an electrolyte in suspension. From the results of chemical analysis of the aqueous suspension after the photoirradiation, it appears that the mercury sulfide in the ore is dissociated into mercuric ions and free sulfur in water by photoexcitation, and hence mercury ore is solubilized into water. Furthermore, the oxidation of the free sulfur into sulfate ions via polythionic acid results in the reduction of mercuric ions to metallic mercury; hence, the metallic mercury is volatilized.     

The human cycle of water: water management and anthropogenic contaminant pathways in Pótam,Sonora, Mexico’s water cycle

Women are the primary decision makers regarding household water sources in many developing nations, but are often overlooked by researchers and organizations as primary water managers. This study took place in Pótam, Sonora, Mexico, during the summer of 2007, with a follow-up visit in February 2008. The study aimed at understand the human cycle of water by identifying potential exposure pathways for water contamination, as well as to understand the link between cultural beliefs, perceptions, and associated health issues. In total, sixty women were interviewed, as well as community elders and the Water Committee president. Discussions of household water use decisions, perceptions of disease causation, and treatment proved crucial in the discovery of potential pathways by which anthropogenic contaminants come into contact with the water cycle in Pótam. Most of the households (87%) believe their water sources are contaminated with biological and or chemical contaminants. Furthermore, of the sixty informants interviewed, seventy percent reported diarrhea as a common symptom. The majority of informants (76%) made a link between consumption of contaminated water and high rates of diarrhea. The study determined that the community is in need of outreach programs geared toward women as household water managers, independent lab analysis of water quality samples, and an epidemiological study to determine the causes for the most commonly reported illness and symptoms.     

Governing water in federal river basins

Regional Environmental Change -     

Quantifying monthly water balance to estimate water deficit in Mayurakshi River basin of Eastern India

Environment, Development and Sustainability - Recorded seasonal variation and uneven distribution of rainfall is one of the major issues to the agrarian society and the domestic water users today....     

Dangerous climate change and water resources in Australia

Water resources in Australia are sensitive to changes in rainfall. Ongoing droughts in south-west and south-east Australia are stressing water resources in the major cities and in agricultural regions. Climate change scenarios for Australia include reasonable prospects of long-term drying, which would exacerbate these issues. The dryer scenarios would entail major readjustments and costs on natural and human systems.     

Alpha radioactivity in drinking water in Quebec, Canada

The median gross-alpha radioactivity found in 236 drinking water samples in Quebec was 52 mBq/l. Only 3% of samples studied have an activity higher than the Maximum Contaminant Level of 555 mBq/l. The median detection limit of the method described is 24 mBq/l.     

Direct methods for radionuclides measurement in water environment

The paper is devoted to the direct method of anthropogenic radionuclide measurement in the water environment. Opportunities of application of submersible gamma-spectrometers for in situ underwater measurements of gamma-radiating nuclides and also the direct method for 90Sr detection are considered.     

Perspectives and limitations of indicators in water management

This paper addresses the issue of indicators for water management by considering why we need them, what the characteristics of a good indicator should be, how they can add value to policy and decision-making, and what are their limitations. There are a vast quantity of data available on water in Europe from which a range of basic trend indicators has been derived. Most of these indicators address "what is happening?"-type questions. Some indicators go further and address "does it matter?" questions by assessing trends against prescribed standards and targets. There have been some interesting developments in indicators which help to understand the demand side of water management and to assess the relative efficiencies of resource usage in different socio-economic sectors. More effort is needed to bring together relevant social, economic and environmental information interactively to define indicators that address questions about the sustainability of water use and the contribution of the water environment to our overall quality of life. The development of indicators to date has concentrated on making the best use of available information. However, we now need to move from a position of "best available information" towards "best needed information". This will require better communication between information users and providers. It will also require a rethinking of exactly what our priority knowledge needs are to support policy-making and environmental management. This is essential if we are to obtain the best value from limited monitoring resources by eliminating the current redundancy in reporting requirements and refocusing programmes to deliver priority information needs. Electronic Publication     

Mineral content of drinking water in lowland papua

This study presents concentration of nine minerals (Na, K, Mg, Ca, Cl, Mn, Zn, Cd, Pb) in 31 drinking water samples collected in the Papua New Guinea lowland, where coastal villagers draw water from artificial wells blended with sea water, riverside villagers utilize brackish river water, and inland villagers fetch creek or swamp water whose chemical composition is close to rain water. During the dry season, the coastal well water contains 500 mgL⁻¹ of sodium and 50–90 μgL⁻¹ of lead. The inland creek or swamp water contains very small amount of minerals; on the average, for instance, 0.64 mgL⁻¹ of magnesium, 0.84 mgL⁻¹ of calcium, and 4.78 mgL⁻¹ of water hardness (as CaCO₃). From some epidemiological evidence in industrialized countries, these mineral concentrations are judged to be indicative of high risk of cardiovascular disorders.     

Microbial degradation of hydrocarbons in Ismailia canal water

The biodegradation of hydrocarbons was performed in refinery wastewater obtained by natural microbial flora in Ismailia canal water. About 87% of hydrocarbons were degraded after 9 days under simulated natural conditions. It was found that the addition of fuel oil to the canal water, which already contained significant amounts of refinery wastewater, retarded biological degradation. Percentage of degradation was found to be 67%. This increase in the hydrocarbons concentration affects dramatically on the generation rate of microorganisms present naturally in canal water.     

水资源权属管理改革形势下水权确权登记制度研究

水资源作为一种公共资源,由于其产权制度的不明晰,导致水资源的利用效率低下,污染和浪费现象严重,水环境形势严峻,水资源权属管理制度亟需改革。水资源权属管理应该重点关注水资源的使用权,包括取水权、农村集体经济组织水使用权、少量用水权和应急用水权。水资源确权登记是水资源权属管理改革中的基础和根本环节。文章通过演化博弈模型构建用水户之间的复制动态和进化稳定策略,论证建立水资源确权登记制度的理论支撑,结果表明一个区域内取水量越小,采取超额取水策略的用水户比例越大,当采取超额取水策略的用水户比例较高时,区域内各个用水户的期望收益和整体期望收益都较低,极易造成水资源使用过程中的用水矛盾冲突,而用水户采取限额取水策略能够增加总体的期望收益。本文明确了水资源产权确权与登记制度的主要含义,重点研究了水资源确权登记的范围包括取水权和农村集体经济组织水使用权,并在此基础上明确了取水权和用水权的确权主体和确权内容、水权确权登记的机关、确权和登记的具体程序,提出水资源确权在整个确权登记过程处于主导地位,而登记是取水权交易的前提条件,在此基础上提出对当前取水许可制度进行改革,按照产权制度的要求,强化水权的权属管理和水权的法律保护。据此,本文提出中央机构应与地方政府相互配合,明确分工,密切结合实际,做好水资源确权登记工作,改善水资源权属管理混乱的现状,加快水资源权属管理改革。