“How to fix things by putting a lot of duct tape.” A couple of years ago, Professor Manuel Herrador he said he was “convinced that at some point in the future people will look at how we build today and will think the same as when they tell us that surgeons used to bloodletting and poultices”. Herrador knows what he is talking about, he is a professor of Structural Concrete at the University of Coruña and has been very interested for years in what this concrete will be like in the world to come.
I couldn’t stop thinking about that idea as I walked away from the “unused” dam at Rules and reached the white villages of the Alpujarra in Granada. There, in just a handful of kilometers, you can see a textbook case in which we have tried to fix with “a lot of brute force”, things that could be done in a much more surgical, much more economical and much more sustainable way. And all this with a medieval technology that is about to be lost.
How to stop time? That is the question that farmers had to ask themselves who, in the middle of the Middle Ages (or even before) realized that yes, Sierra Nevada was filled with snow every year; but just as it arrived it went to the sea. The stone of the high Penibetic peaks meant that as the thaw started, the water quickly descended towards the Guadalfeo and, from there, reached the Mediterranean in the blink of an eye.
There is no doubt that they could not stop the huge wheel of the water cycle, but could they slow it down? In other words, was there a way to ‘entertain’ the water? The answer was called “acequia de careo”.
A medieval technology… that works Unlike normal ditches, careo ditches do not serve to “spatially” distribute water. Its main function is not to carry the precious liquid from the rivers, ponds and torrents to the farmland. Its objective is that “this water resurfaces further down, although at a much later time, after the thaw, allowing water to be available in the dry summer period”: entertain her. The careo ditches were a dense network of capitals that tried to ensure that the meltwater did not flow down the torrents, but rather that it be ‘swallowed’ by the mountain (and, in this way, gain time before it came to the surface through springs). and springs).
Or rather, it worked.. For centuries, this was the fundamental mechanism that allowed mountain agriculture on one of the roofs of the peninsula: the water moved along the slopes of the mountain range, infiltrating it, until it reached chasms specifically identified so that the water accumulated and filtered the earth. However, that ended with the rural exodus and migrations to the cities. The large careo ditches of the Andalusian penibéticas have been more than three decades with a more than deficient operation.
The return to the origins. Fortunately, in recent years efforts to recover and understand them have allowed them to come back to life. And it has not been easy: the first thing these “water sowers” learned is that ditches are not enough. It was necessary to restore the formations of junipers, junipers and the rest of the plant formations associated with these infrastructures because they were key to stabilizing the soil and preventing erosion.
That is, they began to understand that not only “brute force” is needed, but also a lot of “gardening”. If we look at it with perspective, we realize that Sierra Nevada is not only one of the highest mountains in the country, but it is also a huge reservoir. A reservoir made of ditches, sinkholes, spillways, traps, and dams; but, above all, a reservoir made for the future.
Image | UGR