Challenges and Solutions for Global Water Scarcity

Abstract

Climate change, global population growth, and rising standards of living have put immense strain on natural resources, resulting in the unsecured availability of water as an existential resource. Access to high-quality drinking water is crucial for daily life, food production, industry, and nature. However, the demand for freshwater resources exceeds the available supply, making it essential to utilize all alternative water resources such as the desalination of brackish water, seawater, and wastewater. Reverse osmosis desalination is a highly efficient method to increase water supplies and make clean, affordable water accessible to millions of people. However, to ensure universal access to water, various measures need to be implemented, including centralized governance, educational campaigns, improvements in water catchment and harvesting technologies, infrastructure development, irrigation and agricultural practices, pollution control, investments in novel water technologies, and transboundary water cooperation. This paper provides a comprehensive overview of measures for utilizing alternative water sources, with particular emphasis on seawater desalination and wastewater reclamation techniques. In particular, membrane-based technologies are critically reviewed, with a focus on their energy consumption, costs, and environmental impacts.

Keywords: desalination; energy consumption; environmental impacts; reverse osmosis; wastewater reclamation.

Figure 4

Major applications for water reuse and their contributions (data form [138]).

Figure 1

Schematics of the desalination process.

Figure 2

Averaged predicted unit production, capital, and energy costs of SWRO desalination. Climate policy assumed stringent policies to constrain global warming (data obtained from [84]).

Figure 3

The area affected by the saline brine for ∆S > 2.5 and 5.0% (data from [115]).