2 Where does the need arise?
There is a rather obvious question that has to be raised at some point, so we may as well get it over with now: Why do we present ourselves with all these problems? After all, life would be easier without them and we could all go off and do jobs that don't involve them. Do we really need to know everything about the universe? Or to send people into space, at significant cost and human risk? Do we really need to send sound and pictures through space? Do we really need to communicate with people we've never met? Do we really need to educate people about health?
I hope you have at least agreed with the last one, and you can probably see a connection that runs through the points that were used as evidence in the last section. What it illustrates is an order of priority of human needs, ranging from the immediate and essential, to the remote and desirable, and that engineers are active at every level.
Arrange the following items in order of human physical need, with the most basic requirement at the top:
This is only my list, and your own personality will probably dictate how you placed the bottom six. The point is that we can survive no more than a few minutes without oxygen, a day or two without water, and a week or two without food. In extreme environments we can't survive without shelter and/or warmth. As for the rest: well, on this particular scale they can be seen as life's luxuries, although in relatively rich societies we are expecting more and more as our right rather than privilege. Engineers are involved in meeting all these needs at every level and at every depth of complexity.
However you organised the above list, you can see that there is a hierarchy of human requirement where the needs become increasingly refined and complex, and that there are problems, challenges and opportunities for the engineer at every level. All the items in the list could be expanded to consider the engineering involved. Box 4 Meeting the liquid challenge looks at how we meet the fundamental need for a supply of clean water.
Box 4 Meeting the liquid challenges
To all practical intents and purposes, water on Earth is part of a closed system – there is no more or less water on the Earth's surface now than when the first humans were alive. It is approximately 1400 million cubic kilometres of the ultimate recyclable resource, and it is random in its availability. We use it to drink, cook, wash and flush sewers, and without it any one of us would die within a week. Apart from the very air we breathe, it has to be our most basic need.
In temperate zones in the northern hemisphere, we are lucky enough to get a reliable amount of rainfall, which we can store in artificial reservoirs. Water has to be collected from lakes and reservoirs, wells, rivers and underground pools, then treated and transported for domestic and commercial use on a mammoth scale (Figure 6).
Think about the engineering involved in designing, building and lining reservoirs; designing and laying pipes of the right material and capacity; controlling water flow through the pipes; filtration and purification; delivery to domestic and business premises; removing, storing and treating sewage; managing the logistics of supply and demand; and the financial and technical administration of the water system. We may have cause to grumble about the occasional shortage in supply during long dry summers, but our system is generally robust. Generations of engineers have been responsible for the development of reliable water provision around the world (though there are still places where the challenges remain). If you have ever visited a country where you had to rely on sterilised or boiled water, you will appreciate it all the more.
In many poor countries the history of problems caused by drought or contaminated water is well documented. It is currently estimated that 2.4 billion people worldwide lack access to basic sanitation, and over a billion are drinking unsafe water. The engineering challenges posed in these countries (mainly in Eastern and Southern Africa, and South Asia) are different from those met in most of Europe as the rainfall is less reliable, work is often funded by overstretched charities and, although a long-term infrastructure is needed, there is also an urgent necessity to provide instant clean water. Engineers are working on a small, local scale, sometimes having to show innovation with the materials and resources available and meet needs by practicality at the expense of efficiency. They might have to find water below ground, or find a means of purifying water from a river. Engineers may also find themselves becoming educators – passing on their skills and advice to local communities who can then carry out work for themselves.
Internationally, as in any industry, there are groups of engineers and scientists committed to research and development at the boundaries of our existing knowledge. The most recent high-profile discoveries in the water industry are to do with the desalination of sea water, a huge and largely untapped aqueous resource.
Many sectors of engineering are involved in meeting such a basic need as the supply of fresh water. The three classifications of solution – innovation by context, innovation by development and routine – are all represented many times over, and there are numerous angles of opportunity and challenge. If you consider a similar breakdown for each of the needs you listed in Exercise 2, you begin to get some idea of how and where engineering solutions are required. Here's a summary for this case:
designing, building and lining reservoirs;
designing and laying pipes of the right material and capacity;
controlling water flow through the pipes;
filtration and purification;
delivery to domestic and business premises;
removing, storing and treating sewage;
managing the logistics of supply and demand;
the financial and technical administration of the water system.