Avalanche protection in Geiranger

- "No-one will be killed by avalanches and the county road from Grande will not be closed preventively. Only when landslides actually occur," says Kristian Bjørdal of Møre og Romsdal County Council.

Grandefonna and Sildesteinen are the avalanche points that threaten county road 63, Ørneveien from Grande to Geiranger. Over the past 20 years, there have been 16 avalanches. The road has been closed as a precautionary measure against avalanches.

- "Now it will only be closed when an avalanche actually occurs. And it will be quickly reopened when the avalanche masses do not reach the road surface," says Bjørdal.

First radar

He is the construction manager and is leading the work to establish the county's first active avalanche warning system to prevent motorists from being caught by avalanches triggered from an altitude of 1,500 metres and which can hit the road at a speed of 40 metres per second.

- We get greater predictability. The road will be closed less frequently. When it is closed, it can be quickly reopened if landslides do not reach the road surface. Road users are protected by barriers and lights. There are two systems that need to talk to each other.

- The avalanche area will be monitored by two radars. They are placed in two different locations. This means that the radars at Årsethaugsvingen and Homlung will be coordinated with a logic that automatically closes and opens the road. "This is the first time this has been done," says Lars Krangnes of Cautus Geo.

Three objectives

The purpose of the avalanche warning system is threefold. Møre og Romsdal County Council wants to increase road safety. Landslides should not occur on open roads. In addition, the road will have increased regularity. The number of days the road is closed will be reduced and knowledge of avalanche incidents will be improved.

The county council has a joint warning system with Innlandet County Council at Stavbrekka. There, Cautus Geo monitors avalanche conditions with ground-based InSAR. The aim is to ensure the earliest possible reopening of the tourist route over Geirangerfjellet, which is closed in winter.

- "We're now getting our first active avalanche warning system that will keep road users safe throughout the winter. It will provide a safer winter road," says Bjørdal.

700 cars/day

The annual daily traffic on Ørneveien is 700. Somewhat lower in the winter months. There are 495 metres between the two avalanche paths that will now be monitored.

- The avalanche report shows that cars on the road can be stopped before entering the avalanche-prone area, even if they are travelling significantly slower than the speed limit. "We have good experience of warning systems with traffic management," says Krangnes.

A radar-based monitoring and warning system is located in Lom. It was the first of its kind in the country when it went into operation in 2014. In February 2020, it saved lives. At that time, traffic was stopped by the lighting system and prevented cars from being caught by the debris that swept across the road surface.

New year 2025

- "The aim is to establish the facility early in the new year, so that it can be put into active operation as soon as possible this winter," says Bjørdal.

The contract with Cautus Geo is for six years with the possibility of extension. All landslides must be documented with a camera system and visual presentation of data. Including landslides that do not reach the road surface. Everything will be available in Cautus Web.

- There will be both traffic lights and a road barrier. "We look forward to having a safer road. It's about saving lives and limiting the consequences of avalanches to material assets," says Bjørdal.