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Water is life, and without water, there would be no civilizations and a vacant Earth. Water is considered an abundant natural resource on the earth. Water covers 3/4 of the surface. However, 97% of the available water on the earth is salty oceanic water, and only a tiny fraction (3%) is freshwater. This small portion of the available water supplies the needs of humans and animals. However, freshwater exists in underground, rivers, and lakes and is insufficient to cover all the world’s water demands. Thus, water saving, water reuse, rainwater harvesting, stormwater utilization, and desalination are critical for maintaining water supplies for the future of humanity. Desalination has a long history spanning centuries from ancient times to the present. In the last two decades, desalination has been rapidly expanding to meet water needs in stressed water regions of the world. Yet, there are still some problems with its implementation in several areas of the world. This review provides a comprehensive assessment of the history of desalination for wiser and smarter water extraction and uses to sustain and support the water needs of the earth’s inhabitants.

The new coronavirus, COVID-19, spread quickly and causes the death for thousands of people, and a major freeze for the economy and people activities worldwide. This study made statistical analysis for the influences of the environmental conditions such as temperature, humidity, precipitation, wind, and air pollution, which may aid in spreading this virus very fast. The study also investigated statistically the impact of people customs such as smoking, drinking wine, and eating pig meat on the number of deaths among infected people. The study depicted reasons for spreading it in some places much more than others over the world. A statistical software SPSS was adopted to find a correlation among the different variables affecting the virus spread. The results exhibited a significant relationship between the suggested conditions and the virus spread. The study introduced two regression equations for expecting infected people and deaths based on the examined conditions for any region.

Arid countries such as Arabian Gulf countries are suffering from a water shortage, especially with the recent high-water demand. The best solution for this shortage is the management of currently available water resources, through the reuse of treated wastewater for irrigation purposes. This solution also solves the problem of regularization of wastewater discharge, with positive impacts on the environment. This study aimed to apply an innovative, advanced method for treating wastewater with a favorable environment, low economic cost, and less energy consumption. The research investigated the possibility of using natural rocks such as volcanic and zeolite for advanced treatment of wastewater effluent. The research methodology relied on an experimental work in the lab scales and applied on materials available in Saudi Arabia. The experiments included a leaching batch test to first examine what leaches out from these rocks into water. Then, the materials were tested with wastewater effluent. The main mechanism of treatment was based on the absorption process. The results exhibited significant improvement in the water quality of treated wastewater. On the other hand, the results of the leaching tests showed many ions being dissolved from both rocks into water; thus, it is recommended to soak and flush these solid materials with clean water before using them for the treatment process. Further research is required to determine the best pretreated methods to be applied on these rocks to improve their performance as absorbents.

The contamination of fresh groundwater by saltwater intrusion (SWI) becomes a worldwide alarming problem, which threatens all countries depending on groundwater abstraction from coastal areas. Various control and treatment strategies have been suggested to prevent SWI. The construction of subsurface physical barriers is one of the most practical implementation methods to prevent SWI. In this work, the use of subsurface dam as a remediation and protection tool was investigated in a heterogeneous aquifer via lab scale experiments and numerical simulation. The experiments depended on a novel automated imaged analysis method for SWI measurements. Glass beads of different grain sizes were used in sandbox experiments. The simulation works adopted the SEAWAT code for validation of the experimental results and making numerical sensitivity analyses for affecting parameters. Results proved the significant impact of using sub water dams with heterogonous aquifers. The remediation impacts of the dam was captured clearly in preventing and backwashing of the existed SWI. The results revealed also that the heterogeneous aquifers with high permeability in the bottom boundary behave closer to the homogenous aquifers in SWI than those having low hydraulic conductivity in the bottom. Sensitivity analyses results showed that the closer dam to seawater boundary led to the quicker and more effective backwashing process. Results exhibited also that the dam height with 50% of the aquifer dam has the ability to hold the seawater so long as the hydraulic gradient is high and dams with 67% of aquifer height prevent the saltwater intrusion completely.

An underground aqueduct is usually a canal built in the subsurface to transfer water from a starting point to a distant location. Systems of underground aqueducts have been applied by ancient civilizations to manage different aspects of water supply. This research reviews underground aqueducts from the prehistoric period to modern times to assess the potential of achieving sustainable development of water distribution in the sectors of agriculture and urban management, and provides valuable insights into various types of ancient underground systems and tunnels. The review illustrates how these old structures are a testament of ancient people’s ability to manage water resources using sustainable tools such as aqueducts, where the functionality works by using, besides gravity, only “natural” engineering tools like inverted siphons. The study sheds new light on human’s capability to collect and use water in the past. In addition, it critically analyzes numerous examples of ancient/historic/pre-industrial underground water supply systems that appear to have remained sustainable up until recent times. The sustainability of several underground structures is examined, correlated to their sound construction and regular maintenance. Moreover, several lessons can be learned from the analysis of ancient hydraulic works, particularly now, as many periodically hydrologic crises have occurred recently, overwhelmingly impacted by climate change and/or over-exploitation and degradation of available water resources.

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The use of water for domestic and agricultural purpose is not a new phenomenon. It has been used throughout centuries all over the world. After food, water is the basic component of human life and their settlement. This paper considers developments in water dams and water harvesting systems throughout history in different civilisations. The major component of this review consists of hydraulic dams during Pre-Historical Time, Bronze Ages (Minoan Era, Indus Valley Civilization, Early Ancient Egyptian Era, Hittites in Anatolia, and Mycenaean Civilization), Historical Period, (Pre-Columbian, Archaic Period, Classical Greek and Hellenistic Civilizations, Gandahara and Mauryan Empire, Roman Period, and early Chinese dynasties), Medieval times (Byzantine Period, Sui, Tang and Song Dynasties in China, Venetian Period, Aztec Civilization, and Incas) and Modern Time (Ottoman Period and Present Time). The main aim of the review is to present advances in design and construction of water dams and water harvesting systems of the past civilizations with reference to its use for domestic as well as agricultural purposes, its impact on different civilizations and its comparison to the modern technological era. In addition, emerging trends and perspectives are discussed.

The Sultanate of Oman is an arid country with scarce water resources mainly consisting of groundwater. Aflaj are artificial canals constructed centuries ago to transfer horizontally the groundwater to a location at the surface. The water quality of these Aflaj is a very important factor to be considered for healthy and safe use of this water. This paper aimed to study the characteristics of the groundwater through its journey in Aflaj from source point up to its usage point. An experimental programme was adopted to investigate the water quality of Al Hammam Aflaj in Muscat, Sultanate of Oman. The results showed that some positions of the Falaj have high content of some elements, such as Ca, above the allowable values of drinking water standards. Results proved that the water of Al Hammam Falaj in general can be used with caution as a drinking water; however, some care and monitoring should be applied regularly. Results of sodium adsorption ratio (SAR) and soluble sodium percentage (SSP) equations revealed that the water Falaj can be used for irrigation for all soil types but cannot be used on soils with restricted drainage due to its relatively high salinity.

The characterization of dissolved organic matter (DOM) is an important parameter for the management of water resources. In this study, physical and chemical characteristics of DOM in Kushiro river, and its territory (Eastern Hokkaido, Japan) were analyzed using multiple analytical tools. Multiple samples were collected from diverse locations (Kushiro river, Kushiro wetland, compost fertilizer, forest and treated sewage) and compared them against their DOM characteristics. Among the samples, Kushiro wetland samples presented higher specific ultraviolet absorbance (SUVA) values demonstrating DOM derived from vascular plants which are rich in aromatic-components. The SUVA values of the two samples of the Kushiro river were relatively close to those of the wetland samples implying the fact that the river contains high amount of plant derived aromatic DOM compounds, originating from the wetland. The excitation–emission matrix (EEM) fluorescence results showed that generally all water samples have two peaks namely, A and C. These two peaks are related to humic-like substance typically derived from the breakdown of organic matters. The excitation–emission matrix (EEM) fluorescence results of the river samples were also similar to those of the wetland samples, characterized by no appearance of protein, amino acid, polysaccharide, and fluvic like matter, but more pronounced to the aromatic component rich humic acid. Principal component analysis revealed that approximately 88% of the variance in the DOM characteristics might be explained by the type of different sources. From the loadings on PC1 and PC2 in the scores plot, the properties of the DOM of the wetland appeared to be similar to those of the river DOM. Combined results exhibited that the quality of the Kushiro river water is fundamentally inherited from the Kushiro wetland, and the main structure of the river water is characterized by poly-aromatic humic like matter and higher molecular weight.

This study aims to investigate the ability of low cost ceramic membrane filtration in removing three common heavy metals namely; Pb2+, Cu2+, and Cd2+ from water media. The work includes manufacturing ceramic membranes with dimensions of 15 by 15 cm and 2 cm thickness. The membranes were made from low cost materials of local clay mixed with different sawdust percentages of 0.5%, 2.0%, and 5.0%. The used clay was characterized by X-ray diffraction (XRD) and X-ray fluorescence analysis. Aqueous solutions of heavy metals were prepared in the laboratory and filtered through the ceramic membranes. The influence of the main parameters such as pH, initial driving pressure head, and concentration of heavy metals on their removal efficiency by ceramic membranes was investigated. Water samples were collected before and after the filtration process and their heavy metal concentrations were determined by chemical analysis. Moreover, a microstructural analysis using scanning electronic microscope (SEM) was performed on ceramic membranes before and after the filtration process. The chemical analysis results showed high removal efficiency up to 99% for the concerned heavy metals. SEM images approved these results by showing adsorbed metal ions on sides of the internal pores of the ceramic membranes.

Summarization: Since prehistoric times, water conflicts have occurred as a result of a wide range of tensions and/or violence, which have rarely taken the form of traditional warfare waged over water resources alone. Instead, water has historically been a (re)source of tension and a factor in conflicts that start for other reasons. In some cases, water was used directly as a weapon through its ability to cause damage through deprivation or erosion or water resources of enemy populations and their armies. However, water conflicts, both past and present, arise for several reasons; including territorial disputes, fight for resources, and strategic advantage. The main reasons of water conflicts are usually delimitation of boundaries, waterlogging (e.g., dams and lakes), diversion of rivers flow, running water, food, and political distresses. In recent decades, the number of human casualties caused by water conflicts is more than that of natural disasters, indicating the importance of emerging trends on water wars in the world. This paper presents arguments, fights, discourses, and conflicts around water from ancient times to the present. This diachronic survey attempts to provide water governance alternatives for the current and future. Presented on