Freshwater
Water is the foundation for our economies, communities, ecosystems, and quality of life. ~ American politician Kate Brown
Earth is a watery world. There is a tremendous reservoir of water deep underground: 25 times what is on the crust.
70% of the Earth’s surface is covered with water. 97% of it is salty.
Of total freshwater, over 68% is frozen: locked up in glaciers and ice caps (at least for the time being). The other 32% is usable. That constitutes 1,250 km3: about 1/10,000th of 1% of total water on Earth.
So, for such a watery world, the freshwater that plants and animals require is a tiny fraction of planet’s water; and that supply is essentially fixed. Freshwater is indeed a precious resource.
Globally, rivers are the source of most of the fresh water used. Groundwater provides 20% of water needs and half of the world’s drinking water. In arid countries, such as in the Middle East and north Africa, aquifers supply nearly 100%.
Much of this groundwater is shared by 2 or more countries. This makes water management more difficult, and conflict over water rights easier.
Disputes over water are nothing new. The Sumerian cities of Lagsh and Umma fought a 150-year-long war over control of irrigation water ~2500 bce.
Humans once settled where water was plentiful. Economic development shifted populations to places less well-endowed with water. Developed economies use and waste more water: crops, cattle, power plants, and factories prodigiously pound water down.
Electricity production runs on water. Nearly half of the water withdrawals in industrialized countries are just for cooling power plants. During the 2008 drought in the southeastern US, some power plants were within days of shutting down because of limited water supplies.
An atomic reactor consumes 2,650 liters of water per megawatt hour. A coal-fired plant takes 1,900. Generating electricity via natural gas requires 750 liters/mw-hour.
So-called ‘renewable’ energy production is not necessarily an improvement in water consumption. A hydroelectric generator goes through 15,000–68,000 liters/mw-hour; a concentrating solar power plant takes 3,000 liters/mw-hour. Though they have other drawbacks, photovoltaic and wind farms use virtually no water to operate.
Over the past 100 years, human water demand increased almost 8-fold, due to the quadrupling of the global population, increases in per capita food demands, and rising standards of living. ~ Dutch Earth scientist Ted Veldkamp et al
Almost all of the freshwater bodies around the world have been fouled. A 2018 study by the European Environment Agency found that over 60% of European surface waters were badly polluted, despite better protective laws and regulations than the rest of the world. Mercury and other toxic industrial chemical contamination are common, along with pesticide pollution and inadequate waste treatment.
65% of the world’s rivers are ladled with antibiotics; 16% of them at levels dangerous to humans. In Africa and Asia, where sewage and waste are blithely dumped into rivers, are the worst. Europe’s 2nd-largest river, the Danube, is that continent’s most polluted. Even the Thames, generally regarded as one of Europe’s cleanest rivers, is grossly contaminated with antibiotics.
35–45% of water consumption goes to food production in industrialized nations. 80% of this is for irrigation. In Africa and Asia, 85–90% of water extraction is for agriculture.
Global electricity demand from industry in the 1st half of the 21st century is expected to increase 400%, but there is not going to be enough water to meet that demand.
When the well is dry, we learn the worth of water. ~ Benjamin Franklin
Climate change is drying parts of the planet out while dousing other regions. This alone will cause water shortages: 19 of the 29 largest cities in the world depend on locally generated rainfall, via evaporation from surrounding areas, for over 1/3rd of their water supplies. Dependence on rain rises with drier weather, when it does not rain.
Many megacities are not able to buffer themselves from fluctuations in climate and seasonal weather patterns, such as Lagos in Nigeria, or Rio de Janeiro in Brazil. ~ American ecologist Patrick Keys
People in developed countries use 10 times more water at home every day than those in developing countries. Half of the water used is for showering or bathing. 30% goes to washing clothes. Only 0.07% is consumed as drinking water.
As all other natural resources, people are wasteful with the freshwater available. The abundance of Nature has long been taken for granted.
Clean water is no longer a free gift of Nature. It is a shared resource that can be preserved only through judicious investments and active engagement. ~ American hydrologist David Soll
One of the greatest failures of mankind has been an idiotic belief in the price mechanism, which, for natural resources, is based upon extraction cost, with no regard for sustainability. Owing to its easy accessibility, underpricing water has engendered its egregious waste.
750 million people do not have access to safe drinking water. Roughly 80% of wastewater is discharged untreated into oceans, rivers, and lakes. Nearly 2 million children under the age of 5 die every year for want of clean water and decent sanitation. 1 billion people in 22 countries still defecate in the open. 2 1/2 billion people do not have adequate sewage disposal. ~ Swedish diplomat Jan Eliasson in 2015
1980–2016, the top 10% of the most stressed river basins supplied water for ~19% of the global population, 19% of the water used for electricity generation, and 35% of irrigated food production. At present, over 2/3rds of the world population struggle with severe water shortages; nearly half live in India and China.
Around the world, usable freshwater is dwindling. Non-renewed freshwater extraction doubled 1960–2010. Most went to irrigation.
