Hydropower and nature conservation: compensatory measures put to the practical test

Today, the Lonza is a small river. It flows leisurely through the winter landscape between Wiler and Kippel in the Lötschental valley in the canton of Valais; it is peaceful. It is not always like this. “Since the power plant was commissioned three years ago, we have already experienced several flood events,” says Patrick Manz, former project manager for the construction of the Wiler-Kippel hydropower plant. In addition, the water intake is located within the hazard perimeter for wet-snow avalanches. Suitable structural measures on the intake structure and a stream diversion have significantly reduced the potential extent of damage caused by floods and avalanches. “We use the water here to generate electricity. The infrastructure required for this is an intervention in nature. We have to compensate for this intervention, while at the same time protecting the infrastructure against natural hazards.”

Compensatory measures offset the impact on nature

The Federal Act on the Protection of Nature and Cultural Heritage (NCHA) requires that damage to natural habitats caused by technical interventions be avoided wherever possible and otherwise offset through appropriate compensatory measures (see Art. 18 para. 1ter NCHA). In the case of the Wiler-Kippel hydropower plant, various measures were implemented on the left bank of the river to compensate for the interventions required for the power plant and flood protection.

The former campsite in Kippel, which had to be closed due to the risk of flooding, thus gave way to a new side arm of the river. To this end, the site was first freed from contamination caused by lead residues. In addition, a newly created side arm enhances the river and riverbanks ecologically. Kraftwerke Wiler-Kippel AG implemented similar measures further upstream on the Lonza, namely another side arm and the creation of new biotopes. This made it possible to create new habitats along the river, comply with legal requirements and ultimately implement the project, which now produces electricity for around 3,200 households per year.

Agreement on measures is not always easy to reach

It is not always easy to find suitable replacement measures. For example, at the Sousbach hydropower plant in the Lauterbrunnen Valley, which is still under construction, it was not possible to provide compensation directly at the site of the intervention. “The Sousbach is located in a steep and ecologically valuable area. An underground pressure pipeline was deemed not to be eligible for approval, which is why we built the headrace tunnel inside the mountain. Larger replacement measures within the project perimeter were not possible,” says Patrick Manz, who also manages this project. As compensation for the lost habitat of the brown trout in the Sousbach, a section of around 280 metres on the Weisse Lütschine in Lauterbrunnen was enhanced. It can sometimes also be challenging to obtain the consent of those on whose land the replacement measures are to be implemented. If no agreement can be reached or objections are threatened, a project may be delayed further.

Compensation measures have also been introduced by the Electricity Act

Any delay to the projects jeopardises the expansion targets for renewables and therefore the net-zero target by 2050. BKW is also interested in reaching agreements with all parties involved so that its projects can be implemented promptly. It therefore welcomes the fact that, in the case of the enlargement of Lake Grimsel, an agreement on replacement measures has been reached in the so-called "Grimsel Dialogue" between the operator KWO, in which BKW holds a 50% stake, the environmental organisations and the Canton of Bern.

This means that, for the first time across Switzerland, a next step is now pending: compensation measures still need to be defined. Compensation measures are measures with ecological or landscape added value that are agreed in addition to the legally required replacement measures. They are intended to result in a nature-positive impact from the project and apply only to the 16 hydropower projects providing two terawatt hours of additional winter electricity, for which the Electricity Act provides for swift implementation. The negotiations on the additional compensation measures are challenging, as to date there are no clear legal framework conditions, as there are for the replacement measures, or precedents from practice on which to rely. However, an early agreement is important for the successful implementation of the project – if it is not achieved, there is a risk of delay or even a blockade here too.

Could measures and the project be separated in future?

The Federal Council and Parliament want renewable energies to be expanded more quickly. The National Council and Council of States are therefore currently discussing the so-called Acceleration Decree (23.051). Parliament has now also turned its attention to replacement and compensation measures. In future, these are to be separated from the project and, if necessary, even delegated to the canton; the power plant operators would continue to finance them. The National Council will discuss this during the upcoming spring session.

BKW favours partnership-based agreements that bring together the various interests surrounding hydropower. It therefore remains optimistic that the “Grimsel Dialogue” will achieve a first-ever agreement on the additional compensation measures. However, in the event of a potential blockage of the project, separating the replacement and compensation measures from the construction project could have an accelerating effect and help advance the expansion of renewables as planned.

Project for the ecological remediation of hydropower plants

With around 40 projects, BKW is remediating its existing hydropower plants and bringing them more closely into harmony with nature. The revised Waters Protection Act requires this ecological remediation. BKW is expected to ensure free fish migration at all power plants by 2030. In addition, it is improving the impacts caused by hydropeaking as well as the sediment balance downstream of the power plants.

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