Brackish Groundwater And Its Potential To Augment Freshwater Supplies

Accounting for approximately 99% of all liquid freshwater on Earth, groundwater has the potential to provide societies with tremendous social, economic and environmental benefits and opportunities. However, this natural resource is often poorly understood, and consequently undervalued, mismanaged and even abused. In spite of its overall abundance, groundwater remains vulnerable to over-exploitation and pollution, both of which can have devastating effects on the resource and its availability. In the context of growing water scarcity across many parts of the world, the enormous potential of groundwater and the need to manage it sustainably can no longer be overlooked. The 2022 edition of The United Nations World Water Development Report describes the challenges and opportunities associated with the development, management and governance of groundwater across the world.

There has been an exponential increase in desalination capacity both globally and nationally since 1960, fueled in part by growing concern for local water scarcity and made possible to a great extent by a major federal investment for desalination research and development. Traditional sources of supply are increasingly expensive, unavailable, or controversial, but desalination technology offers the potential to substantially reduce water scarcity by converting the almost inexhaustible supply of seawater and the apparently vast quantities of brackish groundwater into new sources of freshwater. Desalination assesses the state of the art in relevant desalination technologies, and factors such as cost and implementation challenges. It also describes reasonable long-term goals for advancing desalination technology, posits recommendations for action and research, estimates the funding necessary to support the proposed research agenda, and identifies appropriate roles for governmental and nongovernmental entities.

The 2020 edition of the WWDR, titled 'Water and Climate Change' illustrates the critical linkages between water and climate change in the context of the broader sustainable development agenda. Supported by examples from across the world, it describes both the challenges and opportunities created by climate change, and provides potential responses - in terms of adaptation, mitigation and improved resilience - that can be undertaken by enhancing water resources management, attenuating water-related risks, and improving access to water supply and sanitation services for all in a sustainable manner. It addresses the interrelations between water, people, environment and economics in a changing climate, demonstrating how climate change can be a positive catalyst for improved water management, governance and financing to achieve a sustainable and prosperous world for all. The report provides a fact-based, water-focused contribution to the knowledge base on climate change. It is complementary to existing scientific assessments and designed to support international political frameworks, with the goals of helping the water community tackle the challenges of climate change, and informing the climate change community about the opportunities that improved water management offers in terms of adaptation and mitigation.

In UNESCO World Water Assessment Programme (WWAP); UN-Water. The United Nations World Water Development Report 2020: water and climate change. Paris, France: UNESCO

Comprising specially selected papers this book presents trans-disciplinary research on issues related to the nature of water, and its use and exploitation by society. The valuable research contained in this book demonstrates the need to bridge the gap between physical, biological, environmental and health sciences. Water is essential for sustaining life on our planet, nevertheless its unequal distribution is a source of permanent conflict. It is predicted that population growth and irregular rainfall, due to climate change, may lead to more restricted access to water in certain regions of the world. This problem is made even more severe by human actions that can cause degradation to nature and the environment. The availability of clean and inexpensive water can no longer be taken for granted as the need for water continues to increase due a growing global population. Heavy water consumers such as agriculture and industry often contribute to its contamination. Water distribution networks in urban areas and soiled water collection systems, present serious problems as well as the need to maintain ageing infrastructures. Possible technologically solutions, such as desalination or pumping systems are energy demanding but, as costs rise, the techniques currently developed may need to be re-assessed.

This Book includes selected papers that has been published in the Water journal Special Issue (SI) on Water Supply and Water Scarcity. Moreover, an overview of the SI is included. The papers selected for publication in the SI include review and research papers on water history, on water management issues under water scarcity regimes, on rainwater harvesting, on water quality and degradation, and on climatic variability impacts on water resources. Overall, the issue identify and highlight the main challenges in water sector, and particularly in management and protection of water resources and in use of alternative (non-conventional) water resources, especially in areas with demographic change and climate vulnerability in order to achieve sustainable and secure water supply. Furthermore, general guidelines and possible solutions for an improved and sophisticated water management system are proposed and discussed, such as the adoption of advanced technological solutions and practices that improve water-use efficiency and the use of alternative water resources, to address the growing environmental and health issues and to reduce the emerging conflicts among water users.