The French ski resort of Tignes will soon be able to offer 365-day skiing after having plans approved to build a €62m (US$66.4m, £52.1m) indoor slope on one of its existing runs.

French architects De Jong (DJA) are behind the 400m (1,300ft) Ski Line snow centre, which will sit at an altitude of 2,000m (6,500ft) and will feature a chairlift to take visitors to the top of the slope, as well as an indoor surf pool at the bottom.

Tignes boasts one of the longest ski seasons anywhere in the world – around nine months – with its glacier runs above an altitude of 2,500m (8,200sq ft) open even during the summer months. As such the resort is very popular as a training destination for ski racers off-season and for tourists.

Tignes mayor Jean-Christophe Vitale said in a statement that the move will make snow-sports possible 365 days a year – something the resort could previously offer when the glacier was bigger – having decreased around 30 per cent in size thanks to global warming over the years.

Environmental groups have raised concerns about the development – approved by the region’s commission for new tourist units – with fears over competition leading to similar projects for other resorts and “denaturising” the alpine landscape.

To snow centre – which is expected to be completed by 2018 – will be powered by the town’s hydroelectricity dam, and will have solar panels and a biomass boiler. The slope will use real snow in the winter months and create artificial snow during the summer.