In 2018, Cape Town, on South Africa, was about to become the first city in the world without water. The local authorities gave an ultimatum to its population, warning that if in 3 months they did not manage to reduce their consumption enough, supplies would be cut off, which would only go to hospitals and other basic services. The reasons were many, some as obvious as a severe drought that lasted for several years. But also others much more curious and unexpected, such as the influence of some invasive plant species.
Fortunately, the situation was reversible, but it remained as a reminder of how serious it can be not take actions on time. At the moment no city holds the title of the first to run out of water, but sooner or later it will come. Therefore, learn from what happened in South Africa it may be a more than good idea. Unfortunately, some things are difficult to fix now, but for others we are on time, as the capenses.
Drastic measures to avoid running out of water
By March 2018, Cape Town reservoirs they were below 30% of its capacity. Furthermore, of that remaining water, less than 20% could be used.
The situation was very serious, since if you wanted to conserve water to supply basic services and to be able to maintain agriculture and livestock it would be necessary to deprive the population of it.
Therefore, it was decided to put a limit on the amount of water that each neighbor could consume. Until then, this city in South Africa had been consuming some 87 liters per day per person, which represents a total of 600 million liters per day throughout its territory. Initially it was decided to restrict consumption by people to 50 liters per day, but later it was further reduced.
Each inhabitant would have to go for their water to collective points, in which it would be ensured that no one took more than 25 liters per day. Little more than a shower. That was the maximum; although, of course, each neighbor was invited to consume even less. Fortunately, this measure was sufficient, the reservoirs recovered and, now, three years later, this is no longer such a serious concern. Now, how could it be that they got to that situation?
Drought and invasive species
In the years before 2018, this South African city had seen increase your population sharply by 50%. This, logically, required a much higher water consumption than what had occurred so far.
To this was added an intense drought, which lasted for three years, throwing the water levels in the dams towards historical lows. Climate change was painfully showing its claws. But that is not all.
Also something as seemingly innocent as the presence of invasive plant species was behind excessive water consumption. This is, for example, the case of pine and black acacia. As he explains in his book History of invasive species the biologist Angel Lion Honeycomb, it is estimated that these plants can consume 100 million water per day. It is a very important part of the total consumption of the city; So while they cannot be singled out as the only culprits, they are important pieces in the puzzle that explains why this city came so close to breaking a sad record.
Can anything be done to avoid all this? Of course, the measures implemented to combat climate change. But without forgetting the role of invasive species. There are invasions, both of animals and plants, that occurred many years ago and are already very difficult to solve. But at least it is important to pay attention to their populations. And it is that seemingly insignificant details may be behind such dramatic milestones as what almost happened in this South African city.