The longest MESIL (Mise en Souterrain d’Initiative Locale – Undergrounding by Local Initiative) project in France was completed on 20 October 2020, in Montpellier. RTE conducted this exceptional project over several years in collaboration with metropolitan authorities.
Four high-voltage cables, including two at 225 kV, were buried by RTE, allowing the old overhead lines to be taken down. With a total of 13 km of lines taken down and 36 pylons removed, the project has freed up land for economic activities that will support Montpellier’s development. It will also benefit those who live and work in the region by improving the quality of their urban environment and landscapes.
The project represented an investment of €18.6 million, of which €13.6 million was financed by Montpellier Méditerranée Métropole.

The next MESIL project will be completed in 2023. It will involve undergrounding five overhead power lines running through the towns of Clamart and Le Plessis-Robinson, in the Paris region.
A total of 14 km of overhead lines will be taken down and 18 km of underground lines created, with security of supply to the area guaranteed throughout the project. In all, 54 km of power cables will be laid unground. Launched in 2017, this project will allow Clamart and Le Plessis-Robinson to realise their plans to enhance their attractiveness by building 350,000 sq m of new homes and 85,000 sq m of retail.
