Spain broke a record in 2021, that of having demolished 108 infrastructures obstructing its waterways, according to Dam Removal Europe, a collective of seven environmental NGOs. No other country has done more in Europe. According to the Spanish daily The country, these obstacles are mostly dams and dykes. There would be some 171,000 across the country – according to an estimate by the Amber project (a European atlas which lists dams across the Old Continent), cited by the Madrid newspaper – over the 187,800 kilometers of rivers flowing into Spain. Some of them are “intermittent” et “have ceased to flow freely for some time”, adds center left newspaper.
“Although the usefulness of hydraulic works is obvious [pour, par exemple, irriguer les terres ou contribuer à la production d’énergie dans les centrales hydrauliques]many constructions have become obsolete over the years”, develops daily life in Madrid. Before adding:
“Nowadays, it is considered that freeing these waterways, allowing them to re-enter their banks, not only has great environmental benefits, but is also the best way to prevent flood damage.”
This argument raises “a lively debate”, nuance The country. In some areas of Spain, dams are essential to prevent watercourses from flowing towards homes in the event of flooding.
The importance of “conveyor belt” sediments
On the contrary, in other cases, they can block the transport of sediments. “When an obstacle stands on [le cours d’eau, qu’El País compare à “un tapis roulant”], sediment accumulates there, while the treadmill continues to move forward. This has many implications for water flow, the erosion it causes and the retreat of estuaries and beaches, where the conveyor belt arrives with much less input than before.”
Another strong argument put forward by the newspaper, the removal of dams makes it easier for fish to circulate in the waterways.
The destruction of several hydraulic dams is part of a European Union strategy in favor of biodiversity. By 2030, the EU wants to restore the free flow of at least 25,000 kilometers of rivers in European countries. In a report published in 2021, the Spanish branch of the NGO WWF identified 5,400 dams as priorities for demolition in Spain, “which she says could free up more than 17,000 kilometers of waterways,” concludes The country.