When the last drop falls

Unrealistic? Not really because water scarcity is becoming an increasingly major problem worldwide. At the moment, the best-known example is Cape Town. At the city’s airport tourists are currently greeted with somewhat strange looking signs informing them to “Slow the flow: Save H2O” or “Don’t waste a drop!”. These slogans are just two of many instructions for tourists and residents to be careful with water. Due to unusually dry winters over the past three years, the South African city is likely to become the world‘s first major city to run out of water. This emergency situation makes it clear that mankind is still highly dependent on nature when it comes to sustainable water supply.

Although water covers almost 70% of the Earth‘s surface, drinking water, in particular, is not as abundant as one might think. Only 3% are actually fresh, drinkable water. The World Bank classifies water scarcity as the situation when people in a particular region have less than 1,000 cubic meters of fresh water per person per year. According to the UN, the global demand for freshwater will exceed the supply by 40% in 2030. The reason for this is a combination of climate change and population growth. But already now more than a billion people have no access to water. Another 2.7 billion people suffer from water scarcity for at least one month. A 2014 survey of the 500 largest cities in the world estimates that one out of four is in a state of "water stress".

Among them are also some metropolises around the globe that you probably do not have on the radar when it comes to poor water supply. The Brazilian financial center Sao Paulo, in whose surroundings there is also an ANDRITZ location, is one of the ten most populous cities in the world. Already in 2015, the city faced a similar scenario as Cape Town. The main water reserves fell below 4%. At the height of the crisis, the city, with more than 21.7 million people, could only ensure a classic water supply for less than 20 days, and police had to escort the vehicles transporting water to prevent lootings. It is believed that a drought that affected southeastern Brazil in previous years caused the situation, but a UN mission in São Paulo also criticized the "poor planning and investment" of state authorities. The water crisis was officially "ended" in 2016, but in January 2017, the major reserves were again 15% below the levels expected for that period - again challenging
the city‘s future water supply.

Across the Atlantic, the situation does not look more "watery". According to official figures of the Turkish government, the country is actually in water stress. Since 2016, the water supply per capita has fallen below 1,700 cubic meters. Conurbations such as Istanbul with 14 million inhabitants repeatedly experience troubles in the water supply in dry months. Local experts now warn that this situation can lead to a water shortage in 2030.

Of all the cities in the world, London is certainly not the first one that comes to mind when you think of water scarcity. The reality is different. London receives 80% of the necessary water from rivers and thus is heavily dependent on the annual rainfall. In most images, the British capital may seem rainy, but with about 600 millimeters of average rainfall per year, it is about less than half of the rain that falls in New York City per year. According to the Greater London Authority, the city is already close to the limits of its present capacity and will most likely face supply problems in 2025 and serious water shortages by 2040.

These cities and countries are only selected representatives of a problem that has more or less hit the entire globe and is pushing for solutions. Water transport is one possibility. 20% of the world‘s population lives in China, which, however, has only 7% of the world‘s fresh water reserves. 40% of the surface water in the capital, Beijing, is so polluted that it is no longer usable even for agriculture or industrial use. To get this under control, Chinese authorities have launched massive water diversion projects. The Hui Nan Zhuang pumping station in the southwestern part of the Chinese capital Beijing is equipped with eight horizontal double-flow split-case-pumps. They press a total of 60 cubic meters of water per second into two pipes that convey the drinking water to Beijing located 60 kilometers away. The pipes, each with a diameter of four meters, are fed by three pumps, with the fourth unit in each case as standby, which can be activated immediately in an emergency.

Following a similar principle, the state capital of Georgia, Atlanta, is striving to secure a sustainable water infrastructure for future generations. One of the most prestigious projects in this campaign concerns the old Bellwood granite quarry in the northwestern part of the city. This area is to be transformed into one of the largest drinking water reservoirs in the United States, with a capacity of 9.5 billion liters of water (2.5 billion US gallons). In addition to the construction work, the project also includes building two central pumping stations that will transport the water to the population of over one million in and around the city of Atlanta. One of these two pumping stations is the Quarry Pump Station, which pumps 40,834 m³ of water per hour (253 mgd ) every day. This pumping station has an extremely low water level, which in turn creates complex general conditions for transporting the water. Thanks to its technically superior, innovative, and very economical solution, ANDRITZ was awarded this strategically important contract to supply three submersible motor pumps complete with peripheral equipment for this pump station. Completion of the entire project is scheduled for 2019.

On the western side of the United States, you get another turn. The US metropolis Las Vegas lies in a desert region and draws 90 percent of its drinking water from the neighboring Lake Mead. In order to guarantee the water supply for the population of around 600,000 and just under 40 million visitors every year, and also make the supply more efficient, three large double-suction submersible motor pumps with more than 8,000 kW, designed and manufactured by ANDRITZ pump, the water (17,200 m³/h) up to this city in the desert from a depth of 80 meters.

In addition to pipelines, reservoirs and deep wells, desalination plants are another way of obtaining water. After a low point in 2014, seawater desalination has seen an increasing growth and not only in its traditional area around the Arabian Gulf. With enduring water scarcity problems, this area is still likely to retain the largest share of contracted seawater capacity for the future, but China, Singapore and Morocco have also seen significant awards in recent years. There are already around 18,500 desalination plants worldwide that produce almost 90 million cubic meters of fresh water per day. Thus, about 300 million people can be supplied with water. A fast growing number of these plants contain ANDRITZ pump technology from seawater intake to the treatment of seawater as drinking water, irrigation water or for industrial purposes. Depending on the temperature and salinity, these pumps are manufactured in duplex and super duplex steel.
Approaches like these make it clear that cities and countries do not need to be fully dependent on nature for safe and sustainable drinking water supplies. A shortage of drinking and service water is not inevitable. But it is about time that authorities, ministries and financial backers set the appropriate course by making the right and sustainable decisions in order to identify the potentials and opportunities and to implement them in a technically useful and effective way. Thereby, desalination, in particular, will play a major role in the future in order to be able to use a part of the 70% seawater that covers our planet for other purposes.