While most of the earth’s surface is covered in water, there are ever increasing water shortages. One cause is obvious: the human population is increasing and the same amount of water is being spread among an increasing number of people. So, there is less water per person as our population increases.
Water is also being used in more ways than before, and industrializing countries have increased their water use. To illustrate, AI, manufacturing and agriculture use massive amounts of water, often in places that are ill-suited to such activity. In some cases, water can be reclaimed and re-used, but not always.
It is not just the amount of water that matters, but what it can be safely used for. As we contaminate water, we decrease the usable water supply. In some cases, we transform it from a resource to a waste that must be sealed away. Industrial chemicals, fertilizers, and even radioactivity are examples of water contaminants. Fracking, for example, contaminates water—even when it is done properly. While contaminated water can sometimes be re-used, it is usually unfit for human consumption. While it can be argued that contamination is limited and the amount of water vast (“the solution to pollution is dilution”), the earth’s water is obviously still finite. That means that as water is contaminated, the amount of usable water is reduced. If this goes on long enough and the water is not decontaminated, the effects will be significant. While worldwide contamination is of concern, what matters to most people is not the total available water, but what is available to them. In addition to contamination, there is also the impact of climate.
While some deny climate change or the role of humans in the process, it is well-established historical fact that the climate does change and the ruins of ancient cities attest to this. In these cases, it is the location of water that matters and shifts in climate (whatever the cause) can create zones of shortage. This is happening today, just as it happened in the past. While the total water on the earth is not really impacted by climate change, the location and quality of the water is affected. For example, while drought in one area does not mean that the earth has less overall water, it does mean that the people living there have less water. Climate change can also cause contamination. For example, my adopted state of Florida is plagued by blooms of toxic algae which might be impacted by the changing climate. While some might taunt those concerned with this for being lake huggers, these outbreaks impact what matters most to the “practical folk”, namely money. Florida, after all, generates revenue from tourism and few want to travel to look at green slime. There is also the concern with the water supply as green slime is not safe to drink. While it is possible to continue the litany of water worries, the above should suffice to show that water shortages are a concern. This raises the question of how to deal with the problem.
Environmentalists have been arguing for years that the solution is to reduce pollution and address climate change. While a reduction of pollution has been a general trend in the United States (thanks in part to Richard Nixon creating the EPA), the current political environment favors an increase in pollution and a decrease in regulation. The moral value behind this view is that environmental costs should be shifted from those who profit from causing damage to those impacted by the damage. For example, rolling back regulations on what companies can dump into the water reduces their costs, but imposes health costs on those who drink contaminated water. The principle of fairness would seem to require that those who make the profit also pay the cost, but politicians are very selective in their concerns about fairness. Because of the current political climate, we should expect an increase in water contamination.
One controversial solution is to recycle waste water, especially sewage, so that it can be used as potable water. While recycling always involves some loss, this would allow cities to address water shortages by reusing their water. It would also have environmental benefits, if the waste was dealt with properly (and, interestingly, sewerage can provide valuable raw materials).
One major obstacle is the cost as recycling water for human consumption requires infrastructure. However, this cost can be worth it in the face of water shortages. It is, after all, probably cheaper and more convenient to recycle water than to transport water (and that water must obviously come from somewhere).
Another major obstacle is psychological. Many people find the idea of drinking water that was recycled from sewage distasteful, even if the recycled water is cleaner than the water they currently consume. To be fair, there are real concerns about ensuring the water is properly treated and improperly recycled sewage could contain harmful microbes or chemicals. But these are problems that can (and have) been addressed so that recycled sewage is no riskier than a conventional water supply (and perhaps less so in many places).
Even when people accept treated water as safe, the distaste problem remains because some think that drinking water that was recently sewage is gross, even though the water is pure and safe to drink. As such, simply proving it is safe will not solve this psychological problem.
This is analogous to proposals to use processed insects as a food source. Even if the food is indistinguishable from “normal” food, clean, healthy and nutritious, many people think this is gross. This includes people who regularly devour parts of animal corpses (better known as “meat”)
Since this is a problem of feeling rather than reason, the solution would need to focus on changing how people feel about recycled water so they can reason about it. One possible approach is by telling the story of water in general. With a little reflection, people understand that tap water has been recycled countless times. Any water you recently drank was most likely filtered through the kidneys of many creatures over the millennia and probably passed through many humans. It might have even passed through you at one point. As such, all the water we consume is recycled already and was almost certainly disgusting (vulture vomit, for example) at one point. However, the process of cleaning it, , cleans it: the water is then fine to drink. As such, if a person is willing to drink any water, then they should also be willing to drink properly recycled water. Water that was just recycled properly from sewage is no more disgusting than water that was once part of vulture vomit and is now in your coffee or bottled water.
People can still say that it is proximity that matters. Recycled water was just recently sewage, but their bottled water or coffee has (probably) not been vulture vomit for a long time. From a rational standpoint this difference should be irrelevant: clean water is clean water, regardless of how long it has been clean. Unless one believes in some sort of mystical or metaphysical contamination that is undetectable by empirical means, then the rejection of safe recycled water would be unfounded. However, unfounded and irrational beliefs drive much of politics and human decision making in general, so the practical challenge is to influence people to not be disgusted by recycled water. Some might be won over by other feelings, such as positive feelings about the environment or the survival instinct (recycled water is preferable to no water). Hard core campers and hikers, who have sucked up bog water through a filtration straw, might be the easiest people to win over. But such psychological manipulation goes beyond the scope of philosophy, so I will leave this matter to the experts in that field.