The Ter River triples its flow twice a week and for six hours with the aim of maintaining the ecological conditions of the river, which is one of the most affected by the current drought scenario.
As a result of this episode, in February the Generalitat decided to apply emergency flows in this and other rivers. The objective was none other than to preserve the maximum possible water in the reservoirs of the internal basins that had dropped below 16% capacity. Currently, the Susqueda reservoir is at 21% capacity and the Sau reservoir – which had reached a tiny 1% – is at 7.3%.
The emergency flow in the Ter River was agreed to be 600 l/s, but it was decided to gradually reduce it. If its ecological flow was 2,000 l/s, it was first decided to reduce it to 1,400 l/s and subsequently to 1,000 l/s, which is the amount of water currently released. What the Generalitat has ruled out, as a result of the recent rains and snowfalls, is reducing the emergency flow to 600 l/s in the short term.
To maintain the environmental quality of the river, Acció Climàtica has established periodic floods. Hydrotips that are carried out twice a week and for six hours in each maneuver. In the case of the Ter river, 3,000 liters per second are released and in the Muga, 300. In total, in the last two months, about 40 maneuvers of this type have been carried out in these two river courses.
These caused floods prevent the water from becoming stuck in the lower areas of the river. “These unnatural water avenues help to regenerate and oxygenate the water and maintain the quality of natural spaces,” explains Anna Barnadas, secretary of Acció Climàtica, who will apply as many floods as necessary in order to avoid “irreversible damage.” to the ecosystem”.
The emergency flow in the Muga River is 70 l/s, far from the ecological flow which is established at about 200 l/s. With artificial floods that are also carried out periodically, 300 l/s are reached.
In the Llobregat River, taking into account that increases in flow must occur at its lowest point, contributions are made through regenerated water from the Llobregat treatment plant.
Barnadas highlights the importance of these “surgical operations” to guarantee the environmental quality of the rivers. “If there is an ecosystem that reaches a point of no return, we will always put the survival of the ecosystem first,” he highlights.
On the other hand, the Catalan Water Agency (ACA) has created a network of 27 points for biological monitoring in river sections affected by drought and the reduction of flows with the aim of having the main physicochemical data and the most relevant biological indicators. In total, 138,000 euros will be invested to intensify these controls.
