Mitigate Water Scarcity Research Articles

Riverbank filtration and managed aquifer recharge as alternative water supply technologies for India: strengths–weaknesses–opportunities–threats analysis

As part of the Saph Pani project, a rapid assessment of a riverbank filtration site in Haridwar and data from literature on riverbank filtration and managed aquifer recharge in India are used for a strengths–weaknesses–opportunities–threats (SWOT) analysis based on environmental, social, institutional and economic aspects. Both technologies show a high potential for future application in India, where alternative solutions are required to mitigate water scarcity and reduce the over-exploitation of groundwater aquifers.

Assessing the economic impact of North China’s water scarcity mitigation strategy: a multi-region, water-extended computable general equilibrium analysis

This paper describes a multi-region computable general equilibrium model for analyzing the effectiveness of measures and policies for mitigating North China’s water scarcity with respect to three different groups of scenarios. The findings suggest that a reduction in groundwater use would negatively affect economic growth and household incomes. A planned water-transfer project would improve economic development and reduce the over-exploitation of local water resources, while water demand management policies would improve water-use efficiency through reallocating water to those sectors having a higher marginal product value. Several important policy implications are drawn from these findings.

A simple approach to assess water scarcity integrating water quantity and quality

Water scarcity has become widespread all over the world. Current methods for water scarcity assessment are mainly based on water quantity and seldom consider water quality. Here, we develop a simple approach for assessing water scarcity considering both water quantity and quality. In this approach, a new water scarcity index is used to describe the severity of water scarcity in the form of a water scarcity meter, which may help to communicate water scarcity to a wider audience. To illustrate the approach, we analyzed the historical trend of water scarcity for Beijing city in China during 1995–2009. The results show that Beijing made a huge progress in mitigating water scarcity, and that from 1999 to 2009 the blue and grey water scarcity index decreased by 59% and 62%, respectively. These achievements were made through great efforts of water-saving measures and wastewater treatment. Despite this progress, we demonstrate that Beijing is still characterized by serious water scarcity due to both water quantity and quality. The water scarcity index remained at a high value of 3.5 with a blue and grey water scarcity index of 1.2 and 2.3 in 2009 (exceeding the thresholds of 0.4 and 1, respectively). As a result of unsustainable water use and pollution, groundwater levels continue to decline, and water quality shows a continuously deteriorating trend. To curb this trend, future water policies should further decrease water withdrawal from local sources (in particular groundwater) within Beijing, and should limit the grey water footprint below the total amount of water resources.

Impacts of urbanization on groundwater quality and recharge in a semi-arid alluvial basin

► We sampled and analyzed groundwater wells previously analyzed for tritium in the late 1980s to early 1990s. ► We analyzed groundwater samples for tritium ( 3 H), helium-3 ( 3 H/ 3 He), chlorofluorocarbons (CFCs), and water quality. ► 3 H– 3 He groundwater ages ranged from 22 years before 2009 to modern recharge. ► CFCs were anomalously high. ► Non-point source pollution in runoff and/or leaky infrastructure is the most plausible source of this contamination. The management of groundwater resources is paramount in semi-arid regions experiencing urban development. In the southwestern United States, enhancing recharge of urban storm runoff has been identified as a strategy for augmenting groundwater resources. An understanding of how urbanization may impact the timing of groundwater recharge and its quality is a prerequisite for mitigating water scarcity and identifying vulnerability to contamination. We sampled groundwater wells along the Rillito Creek in southern Arizona that had been previously analyzed for tritium in the late 1980s to early 1990s and analyzed samples for tritium ( 3 H) and helium-3 ( 3 H/ 3 He) to evaluate changes in 3 H and age date groundwaters. Groundwater samples were also analyzed for chlorofluorocarbons (CFCs) and basic water quality metrics. Substantial changes in 3 H values from waters sampled in the early 1990s compared to 2009 were identified after accounting for radioactive decay and indicate areas of rapid recharge. 3 H– 3 He groundwater ages ranged from 22 years before 2009 to modern recharge. CFC-11, -12 and -113 concentrations were anomalously high across the basin, and non-point source pollution in runoff and/or leaky infrastructure was identified as the most plausible source of this contamination. CFCs were strongly and positively correlated to nitrate ( r 2 = 0.77) and a mobile trace metal, nickel ( r 2 = 0.71), suggesting that solutes were derived from a similar source. Findings from this study suggest new waters from urban non-point sources are contributing to groundwater recharge and adversely affecting water quality. Reducing delivery of contaminants to areas of focused recharge will be critical to protect future groundwater resources.

Rainwater harvesting potentials for drought mitigation in Iran

In order to evaluate the potential of rainwater harvesting (RWH) for mitigating water scarcity in a semi-arid zone of the country (Mashhad-Iran), three typical RWH systems were installed and monitored. The first system consists of 5,000 m² natural ground catchment which was leveled and covered with plastic sheets allowing for maximum possible runoff generation. Surface runoff was conducted into a 500 m³ ground reservoir via a series of draining ditches and an end collection channel. The water collected from a plastic covered catchment was used for irrigation of dryland wheat cultivation. According to the result of two years measurements, grain yield was almost doubled in irrigated plots when compared to conventional rainfed cultivation. In the second RWH system, runoff generated from about 2 ha asphaltic road and parking was diverted into a 1,200 m³ ground reservoir. The results of 2 years measurement for reservoir inflow and outflow indicated that runoff generated during rainy season was sufficient to produce necessary water for irrigating 900 planted fruit trees during successive dry seasons. The last experiment reported here is about a 40 m² roof area which was connected to a plastic tank for runoff measurement. The conclusion was that the proposed RWH system can produce enough water for building's toilets' flashes and other sanitary purposes so that the potable water could be saved considerably. In general, the results of three rainwater harvesting experiments showed the importance of using rainwater for compensating the effect of water shortages which is repeatedly occurring due to the effect of current climate change and ever increasing water utilization for drinking and food production.

Management of water scarcity: A focus on social capacities and options

Water is a scarce resource. It is critical to social and economic development, and directly affects the behaviour of society. With close links between society and water management, the importance of social and economic approaches to management of water scarcity is increasingly being recognized. The focus is here on the adaptive capacity of societies both for policy making and for conflict resolution to address water scarcity, recognizing the limitations in these adaptive capacities. Social resource scarcity could limit not only capacity to address water scarcity but also have wider social security implications for adaptive processes. There is therefore a need to develop policy options to stimulate adaptive processes and strengthen social resource capacity. Further, the paper discusses the links between water scarcity and its driving forces, such as population increase, environmental degradation and unequal access to water, and the various categories of related conflicts.The need to consider the social resource capacity of countries and societies and the use of alternative indicators for this purpose is addressed using the UNDP Human Development Index as a proxy for the social adaptive capacity of societies. A broad programme of research and capacity building in the use of a composite biological-social index could be expected to trigger a better understanding between disciplines and re-focus technical cooperation programmes on social issues.While markets can sometimes react efficiently to mitigate water scarcity, the necessary institutional conditions are seldom met. Social, environmental and equity parameters also need to be considered in applying market approaches, and neo-classical water resources economics is losing ground to economic paradigms related to political and evolutionary processes.Macro- and sectoral issues are increasingly at the forefront of the water scarcity debate, involving a range of questions: from virtual water, high costs of O&M, to privatization of water sector operations. Macro and sector policies often have an important impact on realization of socio-economic and environmental benefits from present and future investments in the water sector. A country's overall development strategy and use of macro-economic policies, including fiscal, monetary and trade policies, affect water demand and investment. As a consequence, there is need for an integrated approach encompassing social, economic and environmental policies.The paper draws from examples on water scarcity management that were presented in a recent FAO electronic conference and in regional expert consultations on water scarcity management in the Near East.

The Balmer: Paschen ratio in the chromosphere and the equilibrium populations of hydrogen angular-momentum states

Mexico, the United States, and Canada are home to a diverse array of river systems. As is the case for rivers across the globe, complex mixtures and interactions of stressors have fundamentally altered the structure and function of these ecosystems. Here, we summarize the intensity and extent of major regional stressors to North American rivers and their impacts on important physical, biological, and chemical properties. The large lakes ecoregion is impacted by broad-scale physical alterations of watercourses, which include both point and nonpoint pollution from industry, municipalities, and agriculture. The establishment of invasive aquatic species is another key stressor. The most pressing stressor in polar freshwaters is rapid anthropogenic climate change. Urbanization is a focal stressor in temperate coastal river habitats. Increasing agricultural production, fine-sediment pollution, and nutrient enrichment are major threats to temperate floodplain rivers. Stressors common across temperate upland river systems include increasing populations and urban areas, impoundments and surface-water abstraction, and land-use change. Point-source pollution, nonnative species, and climatic vulnerability are primary stressors affecting tropical and subtropical coastal rivers. Similarly, climate change and human activities that mitigate water scarcity such as impoundments, diversions, crop irrigation, and surface and groundwater withdrawals are principal stressors in xeric and endorheic river systems. Across ecoregions, these and other stressors can interact and cause surprising ecological responses. Further, the development and introduction of new contaminant sources (e.g., genetically modified crops, antibiotics, hormones, pharmaceuticals, and personal health care products) pose new challenges for river conservation.