Shared Rivers, Failed Protection and the Broken Promises of the Albufeira Convention

Spain and Portugal share history, culture, customs, traditions — and rivers. They share mountains and pastures, farming practices and even the Mediterranean diet. Although they do not share a common language, with a bit of effort from both sides, “Portuñol” is, at large, intelligible.

So why is cross-border cooperation for environmental protection so deficient or, as local environmental associations describe it, “practically non-existent?”

In the spring and summer of 2024, journalist Emerson Mendoza Ayala travelled along the three largest rivers the two Iberian countries share — the Douro (or Duero), Tagus and Guadiana — to document the environmental challenges they face and to explore the solutions being studied to better protect them, as outlined in the Albufeira Convention.

Officially called the Convention on Cooperation for the Protection and Sustainable Use of the Waters of the Spanish-Portuguese Hydrographic Basins, the Albufeira Convention was signed in 1998. Twenty-seven years later, environmental groups on both sides of the border say that shared protection mechanisms are failing to deliver. What was signed, they argue, often remains on paper due to inaction or political obstacles.

Yet, scientists and these same groups continue to point toward possible solutions and renewed opportunities for cooperation.

The longest river in the Iberian Peninsula gives shape and life to the Monfragüe Biosphere Reserve and the International Biosphere Reserve that bears its name. It is also a bridge, connecting the World Heritage cities of Toledo and Lisbon and creating a natural and cultural corridor between Madrid and the Atlantic.

“The banks of the Tagus have been my playground,” recalls Alejandro Cano Saavedra, president of the Toledo Platform in Defense of the Tagus. As a child, he bathed in the river in Aranjuez with his father and fished in it in Toledo with his brothers. Back then, “the fish obtained from the rivers and the Tagus were absolutely edible,” he says, mentioning a vast variety of species, including crabs and molluscs. “All the species have disappeared,” he adds with regret.

Cano remembers the Tagus as “a dynamic river,” with floods in spring and winter, low waters in summer, and even beaches along its banks — as can be seen in the snapshots that Cano treasures like relics.

Pollution, he says, began in the 1960s with Madrid’s rapid expansion. Untreated water from the Jarama and Guadarrama rivers inevitably flowed into the Tagus.

“There were no treatment plants — or very few,” he says.

The controversial Tagus-Segura water transfer — an infrastructure connecting the Tagus and Segura river basins — which began in 1979, further aggravated the situation; it reduced the amount of natural water coming from the headwaters of the Tagus and concentrated pollution.

Cano also denounces the lack of an adequate number of treatment plants and purification systems across the Tagus basin. “There are still many villages that discharge their wastewater directly into natural waterways,” he says.

Despite the environmental damage, Cano remains hopeful. He believes it is still possible to reverse the situation and that people could once again enjoy bathing in the Tagus within four or five years — although it all “depends on the political will to do so.”

Two hundred miles northwest of Toledo, close to the Spanish-Portuguese border, José Manuel Pilo, mayor of the picturesque town of Fermoselle (known for its “thousand underground cellars”), is far less optimistic. In 2001, Article 13 of the Natural Resources Management Plan for the Arribes del Duero Natural Area called for proper treatment of urban, industrial, agricultural or livestock discharges to be achieved as soon as possible.

More than 20 years later, Pilo wonders if that goal will ever be met. His municipality of 1,149 inhabitants still lacks a wastewater treatment plant, and its untreated wastewater flows into the international waters of the Duero River, which are part of the Iberian Plateau Transboundary Biosphere Reserve. 

“On the Spanish side, none of the towns located within the natural park have wastewater treatment systems,” Pilo says. “That’s a deficiency that must be corrected as soon as possible.”

Projects like the “New Fermoselle Waste Water Treatment Plant” have been delayed and vastly over budget, leaving the charming village of Fermoselle a “focal point of insalubrity for the whole area and for the Portuguese villages that use the water for their consumption,” Pilo says.

Diffuse pollution worsens the problem. Nutrients and pesticides from agriculture, along with industrial pollutants, run off into reservoirs and rivers, causing algae blooms and contamination.