Sport, sustainability and work: Water management in Lake Certascan

Water is a natural resource that is not only used for drinking, household chores and irrigation, it is also essential for generating 100% renewable energy as well as practising adventure sports and active tourism.

Sustainability is one of Endesa's central pillars and water is a strategic resource, which is why we make such an effort to focus on its integral management. To such an extent that we currently collaborate with more than 40 cultural and sports entities to enable the social and legal use of rivers with safety and respect for the environment. This involves undertaking about 1,400 operations a year to adjust the optimal water flow to make it possible to practise sports like rafting, canoeing, kayaking and canyoning.

In the course of the year, there are about 300,000 sports activities relating to water, which means that it has becomes an engine for economic and social change. These sports are a major factor in the promotion of tourism, cultural activities and they generate almost 2,000 jobs a year in a number of different places. An example of this is Lake Certascan.

Water management in Lake Certascan

Lake Certascan is the largest in the Catalan Pyrenees with a surface area of 61.2 Ha and it is nearly 100 metres deep. The lake is of glacial origin and its crown is located at 2,235.04 meters above sea level, in the heart of the Alto Pirineo Nature Reserve and in the headwaters of the Noguera de Cardos River, in the region of Pallars Sòbira (Lleida).

One of its unusual features is that can be managed thanks to a cavern and a cage made in the 70s. Inside, there is also a micro-turbine that takes advantage of the ecological volume of water that flows from the lake and generates the electricity required to enable remote communication and manoeuvres, which makes it possible to manage and control the lake.

This manageability is of great benefit to the territory. This involves Endesa's technical specialists analysing the hydraulic balance of the lake every day and they use the results to review management planning, which varies depending on how much snow has fallen during the winter.

If a large amount of snow has accumulated, the lake is managed so that, when it starts to thaw, it can accumulate as much water as possible, which reduces risks further downstream and in this way the risks from excess flows are minimised. However, if the winter has been dry, all the water is kept in the lake so that when summer arrives and the natural flows in the river are minimal, the caging and manageability of the lake make it possible for the water to be used to guarantee the practice of adventure sports and other social-cultural activities.

As well as sports activities, another prominent feature is the water release manoeuvre. This has become quite a tourist attraction, as it creates a waterfall of almost 200 m that can be seen from the path that leads to the lake. During the dry summer months, this would simply not occur naturally.

The other parts of the puzzle

Lake Certascan is the most important piece of a complex puzzle, but it is not the only one. The water is redirected to a gallery that can send it to the Tavascan Superior power station or to Lake Rumedo, depending on the need to cover peak energy consumption by those using clean and renewable energy such as hydroelectric power.

The Tavascan Superior power station is one of Endesa's most energy-efficient because with 1 litre of water it is capable of producing 7.6 kW of power. The Montamara reversible power station can also use the water, but in this case it is sent to the Graus reservoir that is linked to the Tavascan Inferior power station.

The water that has passed through the Tavascan Superior power station's turbines together with that from the Tasvascan Inferior power station is stored in the small Tavascan reservoir that is fed through a gallery to the Llavorsi power station. This is responsible for supplying any additional flow required, coming from the main axis of Noguera Pallaresa, so it is ideal for adventure sports and other activities.

All this means that every day a new analysis needs to be made and it requires meticulous planning of the water that needs to be released from Lake Certascan and programming the flow through the turbines of all the power stations so the volume of water necessary for all the activities in the territory is ready.

For all these reasons, the perfect state of availability for all the installations involved is essential. This is why there is a rigorous and studied surveillance and maintenance plan together with strong periodic investments that enable the installations to remain in perfectly safe and available, both for people and for the environment.