Chemistry and Water

The Science Behind Sustaining the World's Most Crucial Resource

Satinder Ahuja

• Publisher: Elsevier
• Year: 2016
• ISBN:
  9780128096055
• Topic: Physical Sciences
• Subtopic: Analytic Chemistry

After air, water is the most crucial resource for human survival. To achieve water sustainability, we will have to deal with its scarcity and quality, and find ways to reclaim it from various sources. Chemistry and Water: The Science Behind Sustaining the World's Most Crucial Resource applies contemporary and sophisticated separation science and chromatographic methods to address the pressing worldwide concerns of potable water for drinking and safe water for irrigation to raise food for communities around the world.

Edited and authored by world-leading analytical chemists, the book presents the latest research and solutions on topics including water quality and pollution, water treatment technologies and practices, watershed management, water quality and food production, challenges to achieving sustainable water supplies, water reclamation techniques, and wastewater reuse.

• Explores the role water plays to assure our survival and maintain life
• Provides valuable information from world leaders in chemistry and water research
• Addresses water challenges and solutions globally to ensure sustainability

Chapter One

Overview

Sustaining Water, the World's Most Crucial Resource

S. Ahuja Ahuja Consulting, Calabash, NC, United States

Abstract

Water is the most crucial resource for human survival after air. This overview chapter shows how we can achieve water sustainability by dealing appropriately with its scarcity and quality by finding ways to reclaim water from various sources.

Keywords

Contaminants; Monitoring; Quality; Reclamation; Sanitation; Sustainability; Water

1. Overview

Water is a crucial resource for human survival [1–6]. Unfortunately, clean safe drinking water is scarce, even though the Earth is made up of 70% water. Only 3% of freshwater is available to us, and, of that amount, only 0.06% is readily accessible. Nearly 1 billion people in the developing world cannot access safe drinking water; they may spend a better part of their days searching for it. On the other hand, those of us who live in the developed world take it for granted. We waste water and are willing to pay too much to drink it from plastic bottles, which have a large water footprint and add significant problems in terms of disposal. Water leaks drain city water supplies. According to the Wall Street Journal of June 22, 2016, p. A3, brittle, aging systems lose trillions of gallons of water every year.

Water is a simple molecule made up of two atoms of hydrogen and one of oxygen, with a molecular weight of 18. It can occur as liquid, solid (ice), and gas (steam). A molecule with such a low weight should be gaseous; however, hydrogen bonding makes it into a unique liquid that quenches our thirst, feeds our crops, and helps us produce energy. It is almost a universal solvent, as most compounds can be solubilized in it at various levels, depending on their polarity. As can be anticipated, polar compounds dissolve more favorably; however, nonpolar compounds can be solubilized at ultratrace levels (below parts-per-million). This means that contaminants in water need to be monitored at ultratrace levels to assure purity and safety for drinking. Hundreds of unregulated contaminants may be flowing from our taps; they are mostly invisible, tasteless, and difficult to detect [7]. Over 700 different chemicals have been found in US drinking water when it flows from the tap. The US Environmental Protection Agency (EPA) classifies 129 of these different chemicals as being particularly dangerous and has set standards for approximately 90 contaminants in drinking water.

The water crisis is the number one global risk, based on the impact to society as a measure of devastation, according to the World Economic Forum [9]. Water sustains life; without water, life would not be possible. This is one of the reasons that our space program is constantly looking for water on various planets to detect potential life there. Here on Earth, we know that water is the most crucial resource for human survival, after air. Benjamin Franklin made this point crystal clear: “When the well is dry, we learn the worth of water.” Many Native American tribes recognized it early as they consider specific lakes to be the source of life, for example, Lake Tahoe (do-wa-ga, “center of existence” to the Washoe). In India, the Ganges and Yamuna rivers are considered holy. There was a time when you could drink the water of the Ganges without any health concerns; this is definitely not possible anymore.

All human beings need a safe and sustainable supply of water for drinking, washing/cleaning, cooking, and growing food. Unfortunately, governments worldwide do not ensure that their citizens are provided with this essential material (one could argue that it is a basic human right). In many countries around the world, taps, wells, and pipes simply do not exist. Even where they do exist, they are often not affordable for the poorest people or are not designed to last. It has been suggested that conflicts in the 21st century will be fought over water rather than over oil. According to a 2003 UN report, 507 documented “conflictive events” occurred over the last 50 years, with 37 of them involving violence and 21 resulting in military action [8].

1.1. Water Scarcity

Water scarcity is defined as “the point at which the aggregate impact of all users impinges on the supply or quality of water under prevailing institutional arrangements to the extent that the demand by all sectors, including the environment, cannot be fully satisfied.” Hydrologists typically assess scarcity by looking at the population–water equation. Water stress is experienced when annual water supplies drop below 700 m³ per person. When annual water supplies drop below 1000 m³ per person, the population faces water scarcity, and below 500 m³, “absolute scarcity.” Water scarcity is a relative concept and can occur at any level of supply or demand. Scarcity may be due to social reasons (a product of affluence, expectations, and customary behavior) or the consequence of altered supply patterns that may be affected by climate change [9].

Global water scarcity is depicted in Fig. 1.1, where the US, Canada, and a few other countries have an abundant supply of water, while a large area of the world suffers from physical water scarcity or lacks economic means to secure water [10]. With the existing climate change scenario, almost half the world's population will be living in areas of high water stress by 2030 (including between 75 million and 250 million people in Africa alone). Sub-Saharan Africa has the largest number of water-stressed countries of any region in the world. In addition, water scarcity in some arid and semiarid areas could displace as many as 700 million people.

Figure 1.1 Global water scarcity. World Water Development Report 4. World Water Assessment Programme (WWAP); March 2012.

Water scarcity already affects every continent. Around 1.2 billion people, or almost one-fifth of the world's population, live in areas of physical water scarcity, and 500 million people are approaching this situation. Another 1.6 billion people, or almost one-quarter of the world's population, face economic water shortages (where countries lack the necessary infrastructure to take water from rivers and aquifers).

Data on water consumption in the world are available from the United Nations (UN/UNESCO). Worldwide water consumption is estimated to be around 914,546 billion liters per year. Agriculture accounts for 70% of all water consumption, industrial usage accounts for 20%, and domestic usage is 10%. In highly industrialized countries, however, manufacturing consumes more than half of the available water. In Belgium, for example, industries use up to 80% of the available water. Over the last 50 years, freshwater withdrawals have tripled. The demand for freshwater is increasing by 64 billion cubic meters per year (1 m³ = 1000 L) because of the following reasons:

• The world's population is growing by roughly 80 million each year.

• Changes in lifestyles and eating habits in recent years require more water consumption per capita.

• Water demand is rapidly increasing because of accelerated energy demand.

• The manufacture of energy from alternate sources such as biofuels has a major impact on water demand because 1000–4000 L of water are needed to produce just 1 L of biofuel.

• By 2025, the UN estimates two-thirds of the global population will live under water-stressed conditions. This problem is further compounded by the fact that nearly one-third population of the world has no toilets; human waste can affect water supplies and cause several diseases from bacteria and parasites.

The water scarcity problem is further compounded by inadequate sanitation for almost 2.5 billion people. Globally, one-third of all schools lack access to safe water and adequate sanitation. Poor sanitation affects water quality; nearly 80% of diseases in developing countries are associated with water quality. Water shortages in this century are among the main problems faced by many societies. Water use has been growing at more than twice the rate of population increase in the last century, and although there is no global water scarcity as such, an increasing number of regions are chronically short of water. Water scarcity is both a natural and human-made phenomenon. There is enough freshwater on the planet for 7 billion people, but it is distributed unevenly and too much of it is wasted, polluted, and unsustainably managed.

A review of rural water system sustainability in eight countries in Africa, South Asia, and Central America found an average water project failure rate of 20–40%. Recently, Gina McCarthy, EPA Chief, delivered a dire warning: the US water supply infrastructure is aging, and states are not prepared to face current and future water challenges, which include scarcity and threats from emerging contaminants [11].

1.2. Water Quality

The world's seas are inundated by a variety of water pollution problems [12]. With a warming planet and acidifying oceans, species from corals to lobsters and fish are succumbing to pathogenic infections. Table 1.1 shows the most acute problem in major bodies of water.

Table 1.1

Pollution Problems in Major Water Bodies

Water Bodies	Most Acute Problem
Baltic Sea (North Europe), Yellow Sea (northeast coast of China), Bohol Sea (in South Pacific), Lake Victoria (Central Africa)	Eutrophication (nitrogen and phosphorus pollution)
Gulf of Mexico, Lake Victoria (Central Africa)	Microbiological
Caribbean Sea, Congo Basin, Victoria Lake, Benguela Current (west coast of Africa)	Solid wastes
Benguela Current, Pacific Islands	Radionuclides

The extensive use of plastics and their careless disposal has led to the pollution of various water bodies. Paul Ahuja, from La Paz, Mexico, reports that a group of more than 1000 volunteers have collected more than 10 tons of trash in coastal waters in just 1 year. In hopes of educating the public, the leader did in-class presentations to more than 3000 youngsters. Large parts of the Pacific Ocean are referred to as “pl...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Dedication
• List of Contributors
• Preface
• Chapter One. Overview: Sustaining Water, the World's Most Crucial Resource
• Chapter Two. Progress and Lessons Learned from Water-Quality Monitoring Networks
• Chapter Three. Impact of Climate Change on Water with Reference to the Ganges–Brahmaputra–Meghna River Basin
• Chapter Four. Forested Watersheds, Water Resources, and Ecosystem Services, with Examples from the United States, Panama, and Puerto Rico
• Chapter Five. Water Quality and Sustainability in India: Challenges and Opportunities
• Chapter Six. Challenges and Solutions to Water Problems in the Middle East
• Chapter Seven. Challenges and Solutions to Water Problems in Africa
• Chapter Eight. Comparative Analysis of Existing Water Resources Data in the Western Balkan States of Bosnia and Herzegovina, Macedonia, Montenegro, and Serbia
• Chapter Nine. Ion Chromatography Instrumentation for Water Analysis
• Chapter Ten. Use of Ion Chromatography for Monitoring Ionic Contaminants in Water
• Chapter Eleven. Can Incongruent Studies Effectively Characterize Long-Term Water Quality?
• Chapter Twelve. Historical Perspectives on Water Purification
• Chapter Thirteen. Evaluation of Animal Manure Composition for Protection of Sensitive Water Supplies Through Nutrient Recovery Processes
• Chapter Fourteen. Effect of Upflow Velocity on Nutrient Recovery from Swine Wastewater by Fluidized Bed Struvite Crystallization
• Chapter Fifteen. Drought-Inspired Economic Use of Water in Wine Production
• Chapter Sixteen. Developing a Global Hydrohub: Singapore's Leadership in Water Innovation
• Chapter Seventeen. Water Quality and Public Health: Role of Wastewater
• Chapter Eighteen. Challenges to Achieving the Sustainable Development Goals: Water Treatment
• Index