On Thursday 9th March 2017 the road between the turning down to Les Brevieres and the dam at the Lac de Chevril will be closed from 11am until 1.30pm. Here’s a look at what’s causing this 2 1/2 hour road closure.
La Combe de la Davie is an area approximately 4 kilometres square in size that is situated between the road above the village of Les Brevieres and the peak of Rocher de la Davie. It goes from around 1700m high up to 3100m at the peak of the Rocher de la Davie.
This large West facing bowl collects a lot of snow over the Winter, and if it’s not controlled a vast amount of snow could come tumbling down a steep narrow gully that opens out over the road just below the tunnel before the turning to Brevieres. This is why from time to time the road is closed while a helicopter is called in to drop explosives with the aim of setting off a preventative avalanche. This is what is scheduled to happen tomorrow (Thursday 9th March 2017) between 11am and 1.30pm.
In the event of an avalanche being triggered naturally when the road is open, there is a safety measure in place. There are red lights by the roadside to stop the traffic which are triggered by cords across the gully. If the top cord is broken the red lights come on for 5 minutes and then go out, unless the lower cord is broken in which case they stay on until the safety team have visited. These also work if there is a flash flood in the summer, for instance, after a thunderstorm. There are also a lot of earthworks or berms below the road to deflect any avalanche away from the chalets of Les Brevieres.
If the controlled avalanche is successfully released tomorrow, it should be a fairly spectacular event. Meteo Mike reckons it’ll be visible from numerous spots around the Brevieres sector of the Tignes Val D’Isere ski area, including just before the sharp 90 degree turn in the piste just below the top of the Brevieres bubble. So, if you’re out and about tomorrow and hear or see a helicopter in that direction, pause and have a gander- it may well be worth it!