In Ticino, between Manno and Mendrisio, there is a 150-kV Swissgrid power line that is crucial for supplying the Sottoceneri region. Set in the picturesque surroundings of the Lake Lugano region, this infrastructure recently underwent major renovation work on the section between Morcote and Brusino. A 66-kV power line operated by the Swiss Federal Railways (SBB) is also installed along the same route. SBB renovated its line between October 2024 and January 2025, while between March and October 2025, Swissgrid replaced the cables that had been laid at the bottom of the lake in the 1980s along a length of approximately 2.8 km. We take stock of this fascinating project with project manager Mauro Dolfini.

Mauro, can you explain the importance of the line replacement project between Morcote and Brusino?

Of course. Electricity is the lifeblood of modern society: it powers homes, transport, businesses and communications. In an increasingly digital and sustainable environment, demand is growing rapidly. This project is part of Swissgrid’s commitment to ensure a flexible, secure and intelligent transmission system capable of meeting the challenges of the future.

What are the main technical features of the intervention?

The existing line, laid in the 1980s, was completely replaced along the pre-existing 2.8-kilometre route, 2.4 kilometres of which are under water. Six new cables were laid for Swissgrid and two for SBB. These cables are essential for ensuring the efficient transport of electricity and the proper functioning of the railway network. At the same time, a fibre-optic cable was laid, enabling the exchange of data between the Lugano and Mendrisiotto areas, which is vital in our increasingly digital society.

How was the work planned?

The project was divided into several phases to ensure the operational continuity of the power lines. This approach allows us to intervene in a targeted manner, minimising disruption. The construction work lasted about six months.

What were the most significant technical challenges you faced?

One of the main challenges was to lay the cables at the bottom of Lake Lugano. The cables had to be inserted into special tubes and transported on reels weighing approximately 25 tonnes. We had to minimise the site areas and operate in a very limited space. It was a fascinating challenge, which we faced with great determination.

What is the planned investment for this project?

Swissgrid’s investment totals CHF 6.8 million. The project is not just a technical necessity, but a conscious choice for the collective good. Interventions like this integrate the most innovative concepts and respond to new consumption habits.

Mauro, one final question, is there anyone you would like to thank for the success of this project?

Absolutely. I would like to thank the entire Swissgrid project team for the commitment, expertise and dedication shown at every stage of the work. It was a complex project, but they went about it with great professionalism. Special thanks also go to Swiss Federal Railways (SBB), a key partner in the initiative: the cooperation was excellent, and always focussed on finding solutions. And we mustn’t forget our suppliers, who contributed to the implementation of such a complex project. It was a real team effort.