Global Water Reserves in 21st Century

Map of Global Aquifiers in the 21st Century

Researchers at McGill and Utrecht University in the Netherlands have recently published a map showing the regions where the use of water from these aquifers vastly exceeds the rate at which they're being refilled by rain. 

The map compares the usage footprint with the actual rainfall a particular aquifer gets. Blue areas receive more rain than is being used up by humans. For example, Russia has plenty of freshwater. But orange or red areas indicate places where irrigation and drinking water use is drawing out more water from the aquifers than the rain can refill.

Water is limited
 
Nature has decreed that the supply of water is fixed. Meanwhile demand rises inexorably as the world's population increases and enriches itself. Homes, factories and offices are sucking up ever more. But it is the planet's growing need for food (and the water involved in producing crops and meat) that matters most. Farming accounts for 70% of withdrawals.

Few of the world's great rivers that run through grain-growing areas now reach the sea all the year round or, if they do, they do so as a trickle. Less obvious, though even more serious, are the withdrawals from underground aquifers, which are hidden from sight but big enough to produce changes in the Earth's gravitational field that can be monitored by NASA's satellites in space. Water tables are now falling in many parts of the world, including America, India and China.

But there are many potential solutions
 
Although the supply of water cannot be increased, we can use what there is better—in four ways. One is through the improvement of storage and delivery, by creating underground reservoirs, replacing leaking pipes, lining earth-bottomed canals, irrigating plants at their roots with just the right amount of water, and so on. A second route focuses on making farming less thirsty—for instance by growing newly bred, perhaps genetically modified, crops that are drought-resistant or higher-yielding. A third way is to invest in technologies to take the salt out of sea water and thus increase supply of the fresh stuff. The fourth is of a different kind: unleash the market on water-users and let the price mechanism bring supply and demand into balance. And once water is properly priced, trade will encourage well-watered countries to make water-intensive goods, and arid ones to make those that are water-light. It is too early to tell how we will decide to manage our global water reserves. 

Water in the 21st Century

Water is a common pool resource in the 21st Century

From the water wars and the pumping races in California in the 1950s to irrigation systems in Spain and mountain villages in Switzerland, all have demonstrated that people are able to draw up sensible rules for the use of common-pool resources like water. Water in the 21st century will increasingly need its own set of sensible rules to meet the new political, economic and environmental realities of the 21st century.

The Colorado River in the US

The Colorado River provides much of the water for many cities and farms in seven states in the US including Colorado, Wyoming, Utah, New Mexico, Nevada, Arizona and California before it reaches México. But flows of water on the Colorado River in the US have been forecast to decrease by up to 30pc by 2050. In the Northern States its water supports cattle empires. In the Southern States especially in California, the river irrigates deserts to produce much of the US' agricultural products, fruit and winter vegetables. And all along the way, aqueducts branch off to supply cities from Salt Lake City, Denver, Phoenix and Los Angeles. Interestingly, the Metropolis closest to Lake Mead, Las Vegas, gets 90pc of its water from this one source. 

Map of Colorado River in US West

Arguments over water tend to have four dimensions – physical, legal, political and cultural. For the physical the standard response is to summon the engineers. In the case of the Colorado River, engineers are already digging a new intake at 890 feet (lower than the current intakes as the water level in Lake Mead has decreased to ensure a guaranteed water supply to Las Vegas). Another response is to call in the lawyers. This was the preferred approach in the 20th century, in the era of the so called “water wars”. Starting with the the Colorado River Compact of 1922 and continuing with statutes, a treaty with México and case law until the 1960s, a truce was achieved. Called the Law of the River, the resulting regime determines who along the river has what right to how much water. 

At least, it does in theory. The problem is that the law took shape after two decades of record water flows, which became the basis for allocation. As a result it apportions more water than there is in the river. For decades that did not matter, since there was so few people. Then the cattle, fruit and people multiplied. The law's seniority rules theoretically mean that, for example, the taps to Las Vegas would be shut completely before agriculture in California were to loose a drop of water. This gives rise to the political dimension.

In the 21st century, cooperation has mostly replaced the old rivalries among agricultural and urban users among the seven river states. Nevada and Arizona have a water banking partnership and Arizona stores excess water in its aquifers to share with Nevada if needed. In California, the water utility of Los Angeles has bought water rights from some farmers. But inevitably arguments still persist. 

This leads into the final dimension which is the cultural dimension. The argument here is directly related to the culture of the US West. For example, does every middle-class household really need a lawn in a desert? In some cases, counties have begun paying their citizens to rip out their turf and opt for a desert landscape garden instead that can be just as chic. 

Egypt and Ethiopia are fighting for the Nile's water too

Most of the water that flows down the lower reaches of the Nile, the world's longest river, comes from the Ethiopian highlands. Up until recently the Ethiopian Government had been content to abide by a Nile River Water Treaty negotiated in 1959. The trouble is the current treaty has strongly favoured the biggest and most influential consumer of Nile water, Egypt. Ethiopia, which has recently overtaken Egypt as Africa's second-most populous nation has joined together with the other upstream Nile nations including Burundi, Congo, Kenya, Rwanda, Tanzania and Uganda to re-write the 1959 Nile River Water treaty taking advantage of the power vaccuum in Egypt's leadership after the Arab Spring. 

The combined population of the upstream countries along the Nile is 240m against Egypt (85m) and Sudan (30m) and South Sudan (14m). There are also plans afoot for Ethiopia to dam its bit of the Blue Nile and to build a large hydro-power capacity that would be the centrepiece of a plan to increase the country's electricity supply five fold over the next five years. These plans will undoubtedly have a big impact on other Nile countries downstream and have the potential to provoke cross-border water conflicts.

 And what about fracking and high water use it requires

In order to extract gas held in the hard shale rock, it is necessary to break up small sections by firing large quantities of water mixed with fine sand and fracking chemicals at a very high pressure to make the shale rock give up its gas. Water has been identified as a serious problem for mining shale gas mainly because of the quantities of it that are needed to successfully frack wells. But worse of all there have already been cases where local ground water aquifiers have been polluted by the harsh chemicals used in the fracking process. It is estimated that the average shale well uses around of 22m litres of water to extract the gas. If as predicted by many energy experts, shale gas extraction goes ahead at full speed, worldwide gas could make up around 25pc of primary energy by 2035 adding further pressure to the common pool resource of water.

So what does the future hold

The Geo-Trade Blog believes there is an increasing awareness of the need to act on the world’s impending water challenge in the 21st Century. Nevertheless growing global resource use highlights the complex interdependencies between water and energy, agriculture, industry, urban growth and ecosystems.

Governments and business need to prepare for long term water scarcity and to consider a framework to share the world's water - a common pool resource. Of particular importance are the challenges to addressing water issues at policy level nationally and internationally, to avoid cross-border water conflict. The Geo-Trade Blog believes that people do have the capacity to  draw up sensible rules for water use in the 21st Century but consideration needs to start now.

Water for the North of China – 南水北调



Map of the three routes for the South-to-North Water Transfer Project to
alleviate the lack of water in the north of China


Water scarcity in Chinese history is a big issue. China has suffered from water scarcity in the north since ancient times. Summer monsoon winds originating in the Indian Ocean sweep into China. When the summer monsoon is stronger, the moisture-laden winds push the rains farther northwest into China. But when the monsoon is weak, the rains fall farther south and east, depriving northern and western parts of China of summer rains.

Recent research on the strength of monsoon rains over the last two millenia has thrown up some interesting results. The research was based on the layers of stone in a 118-mm-long stalagmite dating from 190 AD found in a cave in Gansu Province in China. It has allowed researchers to match, the amounts of uranium and thorium throughout the stalagmite, to tell the date each layer was formed with the “oxygen signature” in the stalagmite that shows the amounts of rainfall—a measure of summer monsoon strength—to those dates. The researchers discovered that periods of weak summer monsoons coincided with the final years of the Tang (618-906AD), Yuan (1279-1368AD) and Ming (1368-1644AD) dynasties, which are known to have been times of popular unrest and social upheaval. In contrast, strong summer monsoons prevailed during one of China's "golden ages," the Northern Song Dynasty (960-1279AD).

Without the strong rains, food becomes scarce causing social problems and unrest. Hence it is no coincidence that China's most successful dynasties all fell in times of water scarcity. In the 20th century Mao was greatly aware of the need to keep the north watered, in 1952, he called for a scheme that would divert water from the southern Chinese rivers to the north to ease the growing water shortages in the cities of Beijing and Tianjin and the northern provinces of Hebei, Henan and Shandong.

The South-to-North Water Transfer Project

In the 21st century, the mammoth task of transferring water to the north has begun. The South-to-North Water Transfer Project is an incredible feat of engineering on a very grand scale, the aim of the project is to transfer at least 44.8bn cubic metres of water each year from the the Yangtze River in the south, to counter the thirst of the north China plain and its 440 million people. It is the largest project of its kind ever undertaken in the world. The rapid growth of megacities — around 22 million people in Beijing and 12 million in Tianjin alone — has put considerable strain on the ground water aquifiers in the north. In recent years, urban and industrial development has often been supplied with water at the expense of agriculture leading to severe water shortages in rural areas.

Map of the the three routes of South-to-North Water Diversion Project

The project will link China's four main rivers – the Yangtze, Yellow River, Huaihe and Haihe – and requires the construction of three transfer routes, stretching south-to-north across the eastern, central and western parts of the country. In August 2002, the project was approved  and work began on the eastern route of the project in late 2002, and on the central route in 2003. The Central route is due to be completed shortly. Work on the western route is more complicated and is not due to be completed until 2050.

But not everyone is in favour

The project has been criticised for its lack of concern for the environmental impact and the human impact on people being relocated to make way for the canal on the central route. Questions about the cleanliness of some of the water being transferred have also been raised. In the US, the New York Times said the project was like "...channeling water from the Mississippi River to meet the drinking needs of Boston, New York and Washington." 

The below video report provides some further opinions on the the South-to-North Water Transfer Project:

Nevertheless, it is clear, that if China is to continue its growth and development in the 21st century, it must resolve the problem of water scarcity in the north. With 22pc of the world's population, China has only 8pc of the world's fresh water which adds to the challenge. Its per capita availability of fresh water is barely a quarter of the world average. Furthermore, the north accounts for around 37pc of the country's total population, but has only 12pc of the country's total water resources. Yet, in the south, about 1,000bn cubic meters of water from the Yangtze River empties into the sea each year. There is no easy solution to this geographical conundrum and the scale of the problem is huge.

The Geo-Trade Blog believes the South-to-North Water Transfer Project provides a practical solution to a tricky geographical problem that goes back thousands of years. The water transfer project appears to be a logical trade-off as long as the north continues to play fair and does not take advantage of the arrangement to develop further at the south's expense by taking a greater share of the water from the Yangtze River. Although if water remains at present levels, there appears to be enough water for all.