Growing Water Scarcity Research Articles

Ultrahigh Water Flow Enhancement by Optimizing Nanopore Chemistry and Geometry.

The high permeability of nanoporous membranes is crucial for separation processes and energy conversions, especially for the world today that is facing growing water scarcity and energy demands. Unfortunately, further improving permeability, without sacrificing the required selectivity for specific applications, is still extremely challenging. Here, we shed light on the mechanisms of extremely high water permeability of artificial nanopores with the aquaporin-inspired pore geometry and propose a simple yet practical optimization strategy by using computational research to relate nanopore chemistry and geometry to permeability performance. We demonstrated that an ultrahigh water flow enhancement, up to 7 orders of magnitude, can be achieved by optimizing the combination of chemical and geometrical parameters of bioinspired artificial nanopores. Moreover, we addressed an existing debate over the water flow enhancement spanning over 10-1 to 105, attributed to the huge differences in chemical and geometrical properties. Our work provides a guideline to the design and optimization of nanofluidic devices with excellent performance.

Dynamics of urban water supply management of two Himalayan towns in India

Abstract Many towns in the Indian Himalayan Region (IHR) are experiencing permanent water crises due to increasing population pressure, urbanization, and poor management of existing water sources. This paper focuses on two towns – Mussoorie and Devprayag in the western IHR – to understand various aspects of the growing water scarcity and urban water management. In the current scenario of a changing climate, natural springs, their main water resource, are drying up. Mussoorie experiences an acute shortage of water in summer, precisely when the town hosts numerous tourists. In Devprayag, religious tourism and in-migration from rural areas contribute to rising demand. The reduced discharge in nearby streams has widened the demand–supply gap. An integrated management of water sources is crucial to solving water problems in Mussoorie and Devprayag. In both towns, little effort has been made towards recharging existing water sources. Detailed planning of the water supply system while being mindful of the floating population, a proper sewage and storm water management system, and rainwater harvesting schemes, are absent. There is an urgent need to adopt a comprehensive approach to solving urban water issues, covering aspects of demand, supply and water resources management in these hill towns for adaptive water management.

Assessment of Water, Sanitation and Hygiene Services in Sub-Saharan Africa

Adequate provision of water, sanitation and hygiene (WASH) facilities are supporting pillars of healthy living. Hence, this review was aimed at the assessment of the status of WASH services in sub-Saharan Africa. The study used secondary data, sourced from the Joint Monitoring Programme (JMP) report by UNICEF and WHO (2015). This data was used to assess the WASH status of sub-Saharan Africa. Other information highlighted in the paper were obtained from existing literature, in peer reviewed journals, conference proceedings, commissioned studies and the internet. Data obtained were presented in tables and further analyzed using percentages. The review revealed thatWASH services are poorly provided in sub-Saharan Africa, with negative consequencies on the health and socio-economic development of people who have poor access to WASH services. Some of the reasons that have led to the poor provision of WASH services in the region are broadly classified into natural and human-related. The natural causes are the region’s extreme climate and rainfall variability, which has been made worst by climate change, resulting in desertification, shrinkage of some water bodies and growing water scarcity; while the human-related causes include, poor governance, weak institutions, poor financing, and corruption in the WASH sector, amongst others. The study recommends the adoption of a comprehensive, inclusive and integrated WASH strategy that fit the peculiarities of each country in the region. This would help in maximizing the benefits of WASH services and the promotion of healthy living in the region.

Water security and the pursuit of food, energy, and earth systems resilience

ABSTRACTThis article addresses the emergence and interrelation of food, energy, and water security in terms of resource use and the ensuing societal and environmental outcomes. For decades, food security and energy security have been well-accepted, operational concepts. Water security is the latest entrant, yet the implications of water insecurity for food, energy and earth systems resilience have not been adequately considered. This article examines how and why this is so – particularly with growing water scarcity and insecurity that may compete with energy and food security – and emphasizes the critical need to link water-energy-food nexus approaches to earth systems resilience.

Public perceptions of reusing treated wastewater for urban and industrial applications: challenges and opportunities

The growing water scarcity and quality deterioration promote the development of new water resources. Development of water treatment technologies has made water recycling and wastewater reuse a feasible solution to current limitations. However, water recycling plan and reuse has been halted repeatedly by the lack of public acceptance. This study focused on understanding public concerns and perceptions regarding treated wastewater reuse. The study also investigated how public perceptions might affect the current and future utilization of the resources in Muscat, Sultanate of Oman. The public’s perceptions and opinions were achieved by conducting a questionnaire survey from 115 randomly selected residents with different backgrounds. The results indicated that the residents were positive to support any possible option that supported human health and the environment. The majority of the statistical society was optimistic about the reuse of the treated wastewater for irrigation purposes (except for non-edible crops), urban practices, recharge of groundwater, and industrial activities. Using as drinking water was the least preferred option according to the survey. The outcome of this survey study can be used to address the public concerns regarding wastewater-reuse practices. Additionally, this study hopes to support the effective management plans in the future.

Group multicriteria model for allocating resources to combat drought in the Brazilian semi-arid region

AbstractThe world is facing a growing water scarcity problem in the most diverse regions. The Rio Grande do Norte (RN), a Brazilian semi-arid region, is facing its severest drought in the last 100 years. Given this context, managing water resources and combating the effects of the drought have become even more important. Decisions made in this context may involve multiple criteria established by more than one decision-maker. To tackle this issue, a multicriteria model for group decisions is proposed in order to rank the municipalities of the region and thus guide the public administration's efforts in tackling the drought and mitigating its effects. The applicability of the model is exemplified by studying the Apodi-Mossoró river basin, for which the PROMETHEE GDSS method was selected and the preferences of three decision-makers were calculated.

An Introduction to the Hyperspace of Penman-Monteith Reference Evapotranspiration

Evapotranspiration is crucial and very relevant to hydrology, particularly under global warming and the growing water scarcity. The FAO Penman-Monteith is the highly used method to calculate the daily standardised reference evapotranspiration (ETo). It utilises seven variables, mostly climatic and produces a complex n-dimensional domain (or hyperspace). No study has presented the internal structure of this 8D space which forms the objective of the present work. To this end, a computer program called HyperET is developed to facilitate the advancement of two intertwined processes: creating windows into the hyperspace and understanding the resulting regions of the domain. The former gives 2D figures for partial analysis and the latter presents significant infeasible regions which are subspaces composed of ETo values outside its chosen minimum and maximum (or thresholds). HyperET is expensive computationally and presents an ETo domain that resembles Swiss holey cheese with three types of infeasible regions and emerging nonlinearity.

Coyote Lake Ranch v. City of Lubbock: a ranch, a city and the battle over surface use

In a time when the competition for water resources is increasing, water law and policy for groundwater is evolving, bringing to the fore the conflict between surface use and groundwater. Unlike the oil and gas context where the mineral estate is dominant, the superiority of severed groundwater to the surface estate has remained uncertain. The recent Texas Supreme Court case, Coyote Lake Ranch v. City of Lubbock, addressed this question, holding that the accommodation doctrine (long applied to mineral estates) applied to groundwater interests in that case. On its face, the case was a dispute between a Texas city and a landowner over the use and damage to surface property caused by groundwater development. The implications of the Supreme Court’s holding, however, run deep and are significant in this time of growing water scarcity. The Coyote Lake Ranch case signals a continued push toward unifying the law governing mineral and groundwater law and emphasizes the need for the courts and the Texas Legislature to be proactive in balancing the interests and rights of all parties. Citation: Bradbury JD, Smith CC, Ory A. 2017. Coyote Lake Ranch v. City of Lubbock: a ranch, a city and the battle over surface use. Texas Water Journal. 8(1):87-96. Available from: https://doi.org/10.21423/twj.v8i1.7054.

Examining the reduction in potable water consumption by households in Catalonia (Spain): Structural and contingent factors

Water consumption by households is influenced by a host of factors, widely investigated in the literature. However, the effects of contingent situations like drought episodes and economic crises, which may strongly restrict direct water use in households, remain less explored, and especially a combination of both. Catalonia, a Mediterranean region, suffered the worst drought episode in the last 75 years in 2007 and 2008, followed immediately by the worst economic crisis also in several decades between 2009 and 2014 (though still fishtailing). Taking it as a case study and using metered water data for the household sector, we propose a generalized linear mixed model in which the influence of both the drought episode and the economic crisis on per capita water consumption by comarques (supra-municipal entities) is assessed using a drought index on one hand, and economic variables and the water price on the other hand. Likewise, demographic, territorial and climatic determinants, as well as environmental behaviour, are also evaluated. The dataset (N = 287) consists of panel data for the forty-one comarques of Catalonia covering the 2007 to 2013 period. Results confirm that the contingent factors analysed have contributed to further reduce per capita water consumption, being significant the drought index and water price. The proportion of elderly people, the household size and the proxy for environmental behaviour, also have a negative effect on consumption; whereas seasonal population has the expected positive effect. However, neither the climatic and economic variables analysed, nor urban density and the proportion of foreign population, are found to be significant. A better understanding of the factors influencing residential water consumption in a context of growing water scarcity and economic downturn may aid policy makers and water managers not only to improve the effectiveness and efficiency of demand-side management measures that affect households, but to address emerging social concerns such as water poverty.

Substituting freshwater: Can ocean desalination and water recycling capacities substitute for groundwater depletion in California?

While the sustainability of resource depletion is a longstanding environmental concern, wider attention has recently been given to growing water scarcity and groundwater depletion. This study seeks to test the substitutability assumption embedded in weak sustainability indicators using a case study of Californian water supply. The volume of groundwater depletion is used as a proxy for unsustainable water consumption, and defined by synthesising existing research estimates into low, medium and high depletion baselines. These are compared against projected water supply increases from ocean desalination and water recycling by 2035, to determine whether new, drought-proof water sources can substitute for currently unsustainable groundwater consumption. Results show that the maximum projected supply of new water, 2.47 million acre-feet per year (MAF/yr), is sufficient to meet low depletion estimates of 2.02 MAF/yr, but fails to come near the high depletion estimate of 3.44 MAF/yr. This does not necessarily indicate physical limitations of substitutability, but more so socio-economic limitations influenced by high comparative costs. By including capacities in demand-substitutability via urban water conservation, maximum predicted capacities reach 5.57 MAF/yr, indicating wide room for substitution. Based on these results, investment in social and institutional capital is an important factor to enhance demand-side substitutability of water and other natural resources, which has been somewhat neglected by the literature on the substitutability of natural resources.

Prior appropriation and water planning reform in Montana’s Yellowstone River Basin: path dependency or boundary object?

ABSTRACTThis study deepens our understanding of the institutional limitations of participatory water planning. Based on an analysis of a participatory planning effort in Montana, U.S.A., we examine the ways in which prior appropriation (PA), an established legal doctrine based on privatized water rights, both constrains and enables the effective functioning of this mode of governance to enhance water conservation practices. In one situation, a state-led proposal to require water-use measuring was undermined by strong libertarian resistance to governmental regulation. As an expression of path dependency, PA redirected the deliberations back to the status-quo. Yet, in another state-led proposal, PA functioned as a boundary object that helped garner consensual support for what is effectively an alternative water sharing plan based on ‘shared sacrifice.’ In this second case, PA functioned as a pragmatic means to facilitate conservation practices to address future projections of growing water scarcity and drought. The study empirically examines the discursive framework of both policy recommendations and the mechanisms that led to their seemingly divergent receptions from planning participants. Evidence is drawn from a systematic content analysis of video recording transcriptions, ethnographic notes taken during meetings, and key interactions observed among planning participants and the research team.

Creating an enabling environment for WR&R implementation.

Reclaimed water is receiving growing attention worldwide as an effective solution for alleviating the growing water scarcity in many areas. Despite the various benefits associated with reclaimed water, water recycling and reuse (WR&R) practices are not widely applied around the world. This is mostly due to complex and inadequate local legal and institutional frameworks and socio-economic structures, which pose barriers to wider WR&R implementation. An integrated approach is therefore needed while planning the implementation of WR&R schemes, considering all the potential barriers, and aiming to develop favourable conditions for enhancing reclaimed water use. This paper proposes a comprehensive methodology supporting the development of an enabling environment for WR&R implementation. The political, economic, social, technical, legal and institutional factors that may influence positively (drivers) or negatively (barriers) WR&R implementation in the regional water systems are identified, through the mapping of local stakeholder perceptions. The identified barriers are further analysed, following a Cross-Impact/System analysis, to recognize the most significant barriers inhibiting system transition, and to prioritize the enabling instruments and arrangements that are needed to boost WR&R implementation. The proposed methodology was applied in the Copiapó River Basin in Chile, which faces severe water scarcity. Through the analysis, it was observed that barriers outweigh drivers for the implementation of WR&R schemes in the Copiapó River Basin, while the key barriers which could be useful for policy formulation towards an enabling environment in the area concern the unclear legal framework regarding the ownership of treated wastewater, the lack of environmental policies focusing on pollution control, the limited integration of reclaimed water use in current land use and development policies, the limited public awareness on WR&R, and the limited availability of governmental funding sources for WR&R.

Systematic Review of Water-Economy Modeling Applications

AbstractIncreasing demand for water coupled with reduced water availability in many regions of the world is leading to growing water scarcity and calls for implementation of a range of technologica...

Photodegradation of micropollutants using V-UV/UV-C processes; Triclosan as a model compound

Non-potable reuse of treated wastewater is becoming widespread as means to address growing water scarcity. Removal of micropollutants (MPs) from such water often requires advanced oxidation processes using OH radicals. OH can be generated in-situ via water photolysis under vacuum-UV (λ<200nm) irradiation.The aim of this study was to investigate the potential of unmasking V-UV radiation from low pressure Hg lamps (emitting at 185 and 254nm), commonly used in decentralized treatment systems, for enhancing MPs removal efficiency. Triclosan, a biocide of limited biodegradability, served as a model compound for MPs that are not very biodegradable. Its degradation kinetics and identification of intermediate products were investigated under 254nm and under combined 254/185nm irradiation both in dry thin films and in aqueous solutions. In the latter, degradation was faster under combined 254/185nm radiation, although the 185nm radiation accounted for only 4% of the total UV light intensity. In contrast, triclosan photodegradation in dry film did not show significant differences between these irradiation wavelengths, suggesting that the enhanced degradation of dissolved triclosan under combined radiation is mainly due to oxidation by OH formed via water photolysis under V-UV. This conclusion was supported by slower TCS degradation in aqueous solution when methanol was added as OH scavenger. Under both irradiation types (254, 254/185nm) three transformation products (TPs) were identified: 2,8-dichlorodibenzo-p-dioxin, 5-chloro-2-(4- or 2-chlorophenoxy)phenol, and 2-hydroxy-8-chlorodibenzodioxin. In-silico QSAR toxicity assessment predicted potential toxicity and moderate-to-low biodegradability of these TPs. Removal of these TPs was faster under 254/185nm irradiation.Considering the low cost, simple operation (i.e. no chemicals addition) and small size of such low-pressure mercury lamps, this is a promising direction. Further investigation of the process in flow-through reactors and real wastewater/greywater effluent is needed for its future implementation in small on-site systems for post-treatment of persistent pollutants.

Virtual water trade and bilateral conflicts

In light of growing water scarcity, virtual water, or the water embedded in key water-intensive commodities, has been an active area of debate among practitioners and academics alike. As of yet, however, there is no consensus on whether water scarcity affects conflict behavior and we still lack empirical research intending to account for the role of virtual water in affecting the odds of militarized disputes between states. Using quantitative methods and data on virtual water trade, we find that bilateral and multilateral trade openness reduce the probability of war between any given pair of countries, which is consistent with the strategic role of this important commodity and the opportunity cost associated with the loss of trade gains. We also find that the substantive effect of virtual water trade is comparable to that of oil and gas, the archetypal natural resources, in determining interstate conflicts’ probability.

River use, conservation and management among riverine communities in Southeastern Nigeria

Water holds important and diverse benefits for society. It is essential for economic and social development and is important for maintaining the livelihoods of people both in rural and urban areas. The connection between people and water dates back to the earliest origins of life and show the cultural values and social differences that are present in societies. With growing water scarcity, competition for the resource, climate change impacts and pollution, integrated water resource management has been increasingly enlisted as a way to better manage the resource. However the problem remains that many water resource planning and management regimes do not capture the views of the myriad of stakeholders and the many benefits of ecological services. This paper examines river use, conservation and management among riverine communities in South Eastern Nigeria using descriptive statistics on primary data collected from a survey of rural households along two rivers in southeastern Nigeria., Although more than 60% of the respondents in the Local Government areas sampled indicated uses of water for various domestic ends and that other uses like recreation, industry and ecosystem services were indicated and that they are able to attach economic values to these roles, the communities lack the capacity for resource management and conservation. It proposes a strong need for public enlightenment and empowerment for effective water resource management. Keywords: Water use, Conservation, Livelihoods, Participation, Common property

Virtual Water Trade and Bilateral Conflicts

In light of growing water scarcity, virtual water, or the water embedded in key water-intensive commodities, has been an active area of debate among practitioners and academics alike. As of yet, however, there is no consensus on whether water scarcity affects conflict behavior and we still lack empirical research intending to account for the role of virtual water in affecting the odds of militarized disputes between states. Using quantitative methods and data on virtual water trade, we find that bilateral and multilateral trade openness reduce the probability of war between any given pair of country, which is consistent with the strategic role of this important commodity and the opportunity cost associated with the loss of trade gains. We also find that the substantive effect of virtual water trade is comparable to that of oil and gas, the archetypal natural resources, in determining interstate conflicts’ probability.

A comprehensive analysis of blue water scarcity from the production, consumption, and water transfer perspectives

The issue of growing water scarcity has been increasingly perceived as a global systemic risk. To solve it, an integrated approach considering different perspectives of water scarcity is at a premise. In this study, we developed an approach to calculate the blue water scarcity (BWS) and integrated the production, consumption, and water transfer perspectives into a single framework. The results are as follows: The average BWS in the Hetao irrigation district was 0.491 during the 2001–2010 year period, which was much larger than the threshold of 0.30, indicating a high water stress level. From the production perspective, the agricultural sector was the largest contributor to regional water scarcity and the average BWS was as high as 0.479. From the consumption perspective, BWS related to virtual water export was much larger than that related to water consumption for making products to be consumed locally and the values were 0.422 and 0.069, respectively. Under the influence of physical and virtual water transfer, BWS changed from 0.242 (medium to high water stress level) to 0.491 (high water stress level). Strategies for reducing agricultural water consumption, such as increasing crop water productivity, improving irrigation efficiency, and promoting more reasonable irrigation water price, could be adopted in the Hetao irrigation district to alleviate regional BWS. Compared with physical and virtual water import, the virtual water export played a more important role in influencing the regional water scarcity, and the increase in crop water productivity, decrease in crop export volume, or adjustment of trade pattern from water-intensive crops to water-extensive ones could be feasible measures to decrease virtual water export for lower water stress, while the trade-offs in the product-consuming regions should be considered.

Multilevel Factorial Fractional Programming for Sustainable Water Resources Management

AbstractThe need for more efficient water use has increased in importance with growing water scarcity and increasing competition among water users. Measuring the economic efficiency of water use has become a useful indicator for water resources management at all levels. This study proposes a multilevel factorial fractional programming model to support water resources management under uncertainty. Linear fractional programming is introduced to provide a practical way for taking into account the ratio of economic benefit to water consumption in the modeling process. This approach allows water allocation plans to be developed on the basis of the optimal economic efficiency of water use rather than economic incentives. A multilevel factorial analysis technique is integrated within linear fractional programming framework to deal with data uncertainty. This technique can quantify the individual and interactive effects of uncertain parameters on system performance and help decision makers gain improved insight i...

Long time-series spatiotemporal variations of NPP and water use efficiency in the lower Heihe River Basin with serious water scarcity

It is of great significance to analyze the long time-series spatiotemporal dynamics of water use efficiency (WUE) to formulating appropriate management measures in response to the growing water scarcity in arid and semi-arid regions. This study analyzed the long time-series variations of WUE in the Lower Heihe River Basin, a typical arid and semi-arid region in China. The net primary productivity (NPP) was first estimated with the C-fix model, then WUE during 2001–2010 was calculated with the NPP and evapotranspiration (ET) data, and the accumulative WUE was further calculated. The results showed that the annual NPP and WUE in the study area ranged from zero to 448.70 gC/(m2 a) and from zero to 2.20 gC kg−1 H2O, respectively, both of which showed an overall increasing trend during 2001–2010. Besides, the spatial pattern of WUE kept overall unchanged during 2001–2010, but with remarkable change in some part of the study area. In addition, the accumulative WUE of the whole study area showed a first sharply decreasing and then gradually increasing trend, but there was still some scope to improve the WUE, and it is necessary to carry out some more specific policies to further improve the water allocation and WUE within the Lower Heihe River Basin. Although with some uncertainties, these results still can provide valuable reference information for improving the water resource management and ecological conservation to guarantee provision of essential ecosystem services in arid and semi-arid regions.