If there is an element that we fully identify with life, it is water. If there is water there is life, and in the Eume hydroelectric plant (A Coruña), there is it at its maximum expression. Anyone who has had the opportunity to walk through its magical fragas knows it, a unique Atlantic forest that extends through a steep valley of deep gorges. Just a few kilometers upstream we find the Eume hydroelectric plant, an infrastructure with a centuries-old technology base and the 'mother' of renewable energies.
That hydroelectric plants have a crucial role in the energy transition is experienced day by day by José Antonio Galván, director of Endesa's Northwest Hydraulic Production Unit. He knows inside out the secrets of this infrastructure built in the 50s of the last century. Operated since the 1980s by Endesa, it is an engineering work in itself, with a spectacular vault dam that at the time was one of the highest in Europe: 101 meters high on foundations and 225,000 cubic meters of concrete.
“At that time and with not so advanced technical means, a lot of manpower was needed. It was a milestone in civil engineering,” explains the head of the Eume hydroelectric plant. Those who started it were unaware that it was one of the most sustainable ways to produce energy there is. His predecessors did not think beyond that of taking advantage of “a driving force that the water had due to the fact that it was dammed and could be turbined.” But that generation was already, from its very conception, renewable energy.
In those early days, it was just another energy that accompanied other more polluting ones, such as thermal energy, from coal, but today that story has changed. “Now it is a guarantee that the rest of the renewables, such as wind or photovoltaic, have a backup in times when that energy is not available due to lack of sun or wind, because with hydraulics we can store water,” shares the director of the center. “We are an energy with a lot of past, but with a lot of future,” he summarizes.
“Our activity does not only take place here, within the central building, we have a close relationship with the rest of the people and organizations in the territory,” shares Galván. One of those people was the senior patron of the Pontedeume Fishermen's Guild, who worriedly conveyed to him a problem detected by the shellfish harvesters: the productivity of the estuary that is formed at the mouth of the river, enormously rich for shellfish, has not stopped. fall.
As a company with strong roots in the Eume and everything that surrounds it, Endesa did not hesitate to undertake the search for the problem and its possible solutions, counting on the University of Santiago to lead a rigorous scientific study to search for the causes. A project that has been pioneering in encompassing, for the first time, a complete evaluation of the estuary: from the quality and changes in the substrate, through the quality and characteristics of the water (salinity, temperature, parasites, etc.) to the modifications at the mouth of the river itself caused by human intervention (works that may modify the channel or the way in which sediments are deposited).
The shellfish harvesters agree: “Where there used to be a sandy substrate, now there is a clay substrate, very rich in organic matter,” says Xosé Lois Otero, researcher at the University of Santiago and coordinator of the study. Therefore, part of the problem may be due to the fact that, for some time now, the texture of the substrate has changed substantially. “It has to do with the water or the substrate, because you have to understand that clams, and bivalves in general, are planted like any other crop,” he adds.
The coordinator of the study supported by Endesa explains: when this type of very fine texture is combined with a lot of organic matter, substances are generated in the sediment that can be toxic for bivalves in general. “The regional administration estimates that 70% has been lost in the productivity of certain species of bivalves, especially the slimy clam, which is the most productive and the one that pays the best,” Otero summarizes.
But do we know the causes of this sharp decline?: “We have been investigating for a year, but we need more time. The hypotheses point to many causes and hence the difficulty,” they say. For Xosé Lois, we must take into account the change in water temperature, which favors the expansion of certain parasites, and also the change in the nature of the substrate, fueled by unnatural transformations that alter the coast, such as breakwaters.
There is still time to draw conclusions, but one thing is certain: “Fundamentally, we are passionate about our knowledge being applied and solving the problems of our Galicians, our people. When this happens, our work gains a lot of value,” highlights the researcher from the University of Santiago. “When with knowledge, in some way, you solve problems for society, the cycle of our activity closes. And that is what we always look for, although it is not easy,” he adds.
The focus of this research, led by the University of Santiago and promoted by Endesa and the Pontedeume Fishermen's Guild, is the estuary, a Galician word that has no translation in another language. “And from there everything is said,” says Otero, “because if it is a unique system, it must be respected as such.” “Any infrastructure activity that is carried out must be thought out several times and must be supported with sufficient scientific information to evaluate whether it is relevant to do it and if it must be done, how it must be done,” he says.
There is too much at stake, as Elena López, Councilor for Tourism and Commerce of As Pontes, highlights. It is not the first time that the municipality, where the coal-fired power plant is located, is in the process of closing, and another combined cycle plant is in operation; It has the support of the electricity company to protect the territory and its valuable resources. Thanks to a rehabilitation process, the enormous shaft of a coal mine and its waste dump, closed for years, are today a natural paradise: As Pontes Lake. Today it is Eume who receives his attention and help.
As López highlights, “it is the leading resource in the entire industrial transformation of our town. For decades we lived with our backs to the river and I believe that is the debt we have with it, respecting it and valuing everything it offers," shares the councilor, who adds: "We have to be aware that what we are as a people comes for nature, for the territory in which we live and we always have to find that balance.”
From their department, they are focused on an environmental inventory to disseminate all the nature around them. With the help of Endesa, they have also promoted industrial tourism experiences, to give value to the entrance to the Las Fragas park through the Eume hydroelectric plant reservoir, operated by the electricity company, an infrastructure that, in addition to being the cradle of renewables, is redefined as an ally in the protection of the entire ecosystem to which it owes so much, upstream and downstream.
