PROCEDURE / PROCESS

Neither. The Gornerli project will be implemented by means of an amendment to the current Grande Dixence concessions. This concession amendment only concerns the Gornerli part; Grande Dixence’s concessions are not affected.

The Municipality of Zermatt is kept abreast of the development of the project and asserts its interests if necessary. Future collaboration and all relevant topics (flood protection, irrigation, drinking water network, etc.) will be handled jointly by the Municipality of Zermatt and Grande Dixence SA.

The population of Zermatt and the other municipalities in the Mattertal Valley that grant the concession will vote on amendments to existing concessions at primary assemblies. The project planning, including the Environmental Impact Assessment, will also be completed so that the population is fully informed when making its choice. The date of these votes has not yet been set because this vote requires a complete dossier, which in turn must be provided by the negotiations with the Association des collectivités concédantes de Grande Dixence (ACC GD) and depends on the determination of the compensatory measures.
The 20 licensing municipalities and the Canton will also have to decide on the residual value agreement.

• The Municipality of Zermatt will enjoy many advantages: – flood protection and an efficient long-term water supply for the whole valley:
  long-term artificial snow cover for the ski area
• ideal conditions to ensure the long-term secure and local electricity supply throughout the year
• additional revenue from water charges as well as from taxes
• long-term added value, as a future shareholder of Grande Dixence SA, as the Gornerli project will further increase the storage capacity and thus the value of Grande Dixence (added value in terms of storage and the ability to regulate renewable energy)
• a major contribution to the security of electricity supply at cantonal and national level

The Canton is currently the licensor of Grande Dixence and participates in the project as licensor.

The current concession and the concession amendments will last until the end of Grande Dixence’s existing concessions, i.e. at the end of 2044. After that, either the concession must be renewed or a new concession granted. In accordance with the current legislation, cantonal participation through FMV is envisaged in this context. Several of the Canton’s services also participate as part of the Gornerli Dialogue in the project’s various support groups.

We understand the concerns of the local population with regard to logistics and take them very seriously. Most of the equipment will be transported using a combination of trains and two temporary cableways, which will be dismantled after the construction phase. Some special transport operations will be carried out by trucks driving through the village, but this will be kept to a minimum. The logistics project is currently being developed and the corresponding contacts with logistics partners and landowners are actual the subject of specific negotiations. An initial presentation of this concept took place during the second public information evening on 4 March 2026.

The volume of the Gornerli reservoir would have prevented the two Mattervispa flooding incidents at the end of June 2024 in Zermatt and would have reduced the flood damage in Val d’Hérens and the entire Zermatt Valley (with the exception of damage caused by the Triftbach, one of the tributaries of the Mattervispa). According to experts, similar or even larger violent events can be expected in the future due to climate change. They will also become more frequent. The Gornerli project will limit these risks, notably through an additional freeboard with a reserve volume of 13 million m³. This corresponds to 16 times the volume of the Z’Mutt reservoir. It will also significantly mitigate local hazards such as glacial lake drainage, debris flows or rockfalls.

Flood protection and water supply will be a priority through the storage of water volumes. Management will be governed by a binding agreement between Grande Dixence SA and the Municipality of Zermatt.

The Gornerli reservoir will ensure that the water required to operate the EWZ power plant (the local electricity distributor) in Mutt is available at all times. It will thus contribute directly to increasing the long-term security of supply of Zermatt. However, this requires investment on the part of EWZ. Discussions are also ongoing with EWZ to find further synergies to cover the local security of electricity supply.

As with any project of this size, they are of several types of challenge. Firstly, there is the question of concession amendments and negotiation of the residual value agreement with the licensing municipalities and the Canton, implementation of ordinary and additional compensation measures and, more generally, environmental issues. In addition, taking into account the presence of the glacier and natural hazards is essential to the project. Implementing such a complex project requires that many, sometimes conflicting, interests be reconciled.

It is one of the largest infrastructure projects in Switzerland. It is clear that unanimity will not be possible. The essential task for Grande Dixence SA is to balance the benefits of this project – the security of Switzerland’s electricity supply, flood protection and water supply – with the impacts on the landscape and nature, as well as local impacts on tourism and the population. These benefits and impacts were already weighed up in 2021 at the Round Table, where the authorities and the environmental and electrical associations agreed that Gornerli should be one of the 16 priority projects.

The concessions for the Gornerli project run until 2044. Grande Dixence pays an average of more than CHF 46 million per year in taxes and water charges to the licensing authorities, including almost CHF 4 million to the Municipality of Zermatt. After this date, the Gornerli facilities, like all the other Grande Dixence installations, will be transferred to the licensing municipalities. This means that from 2045, these municipalities and the Canton will be co-owners of all the facilities. Let’s assume that the project goes live in 2034. The current owners will only operate it for 10 years, but the licensing municipalities and the Canton will then be able to operate it for much longer, at least another 80 years. The potential earnings do not, therefore, primarily accrue to the large energy companies. And the local disruptions and risks inherent in the construction of such a project must be weighed against the long-term added value enjoyed by the region.

Alongside the concession amendments, an agreement must also be reached with the 20 licensing municipalities and the Canton with regard to fair compensation for residual value when the concessions expire in 2044. As the planned investments cannot be amortised over the remaining term of the concessions, i.e. approximately 10 years at most, the compensation for the residual value must be determined jointly by the current owner, Grande Dixence, and the licensors. In order to conduct these negotiations, the Association des collectivités concédantes de Grande Dixence (ACC GD) has been active since November 2025. It is within this framework that compensation for the residual value of the investment for Gornerli will also be negotiated.

Technically, it is not possible to raise the Grande Dixence dam by more than about five metres. The reasons for this are first increased risks associated with the existing tunnel system behind it and second because of the installations downstream of the dam (surge chamber, pressure shafts and valves). In addition, the feasibility of the project from a legislative perspective finally resolved.

Due to its maximum storage potential of 100 GWh, the Dix+ project neither offers an alternative to nor competes with the Gornerli project. It could, however, be a suitable addition in the overall context of developing the Lake Dix facilities with a view to securing the national winter energy supply.

Not at all. We have always said that the initial figures cited in the feasibility study would be estimates of the maximum values, which should be confirmed by further studies. In addition, it has always been clear that the final storage volume and therefore also the final height of the dam depend on the inputs that can be captured in the long term. The storage volume that can be used will depend on the retreat of glaciers.

The current legislation provides for financial assistance for new hydroelectric plants. This measure is intended to lay the foundations for the Energy Strategy 2050, which aims to replace fossil fuels with renewable ones. The amount of the subsidies awarded to individual projects depends on construction costs and electricity price forecasts. Although the Gornerli project is of economic interest, it also relies on subsidies based on forecasts of market prices and final construction costs.

Gornerli is the most important project of the Round Table. The new Electricity Act simplifies the land planning procedure, while retaining the concession and building permit procedures. The adoption of the Electricity Act gives the Gornerli project greater weight in relation to other conflicting national interests, such as nature and landscape protection. In addition, the Acceleration Act limits aspects such as appeals against the 16 hydroelectric projects of the Round Table to the cantonal court. In this respect, the Round Table further agreed that the projects should propose and implement appropriate additional compensation measures.

In Switzerland, each dam is subject to the Federal Act on Storage Facilities and its implementing ordinance. The Swiss Federal Office of Energy (SFOE) is responsible for compliance with the requirements of this legislation and draws up the implementing directives. The SFOE will monitor the project and ensure compliance with all applicable laws, ordinances and directives. Operators will have to take the necessary measures (safety equipment, measuring equipment, tests, etc.).

During the development of the project, Grande Dixence reached the conclusion that the current variant is in total the best. Nevertheless, within the scope of Dialog Gornerli, an analysis of other possible alternatives is currently being discussed with all stakeholders (environmental NGOs, fishermen, Swiss Alpine Club, association of mountain guides) as well as with external experts. Among other things, this includes a two embankments variant proposed at the time by IG Gornerli. The corresponding results will be available in 2026. The solution developed by Grande Dixence continues to be refined. If any relevant new findings from this variants study were to be demonstrated, they would be taken into account by Grande Dixence when designing the project.