MASS MOVEMENTS ALONG ROADS IN THE FJORDS

Most of the roads along the fjords in Western Norway are all year around the scene for mass movement of different sorts and sizes. This may include rock falls, rockslides, landslides, debris flows, mud flows, snow avalanches and rock avalanches.

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By Geologist Christer Hoel, M.Sc.
Read more: Rock Avalanches in the Fjords

Some of the roads are particularly well-known for their high level of mass movements exposed over them. The road E 16 between Bergen and Voss along a fjord area often experience such events. The following are just some examples of what may happen.

Mass Movements along Roads in the Fjords

The result of the rockslide near Stanghelle.
The result of the rockslide near Stanghelle.

In March 2010 a rockslide with large blocks fell down near the eastern opening of a road tunnel near Stanghelle between Vaksdal and Dale. Fortunately no vehicles were hit by this rockslide, but it had a large potential to create a terrible accident.

Such events have happened numerous times along the E 16 road between Bergen and Voss, and have contributed to the fact that this road has got the reputation as being Norways most dangerous road. The last 20 years much more than 300 different mass movements have happened along this road.

Events with similarities have occurred many other places too, like e.g. the landslide between Eidfjord and Brimnes in inner Hardanger that happed in June 2011.

After the landslide went between Eidfjord and Brimnes.
After the landslide went between Eidfjord and Brimnes.

 

In order to try to control potential rockslides, landslides etc. the Norwegian Public Roads Administration make efforts to secure the sides of hills and mountains.

A well-known sight on roads in Western Norway is that steep mountain sides are being secured with bolts and different sorts of net.
A well-known sight on roads in Western Norway is that steep mountain sides are being secured with bolts and different sorts of net.

A well-known sight on roads in Western Norway is that steep mountain sides are being secured with bolts and different sorts of net. This is work not without danger for those who perform it. Suddenly released blocks and stones can fall. Other efforts are sometimes also made, like building mounds to collect the falling material.

Due to heavy precipitation, which is quite common in Western Norway, many brooks and small rivers sometimes create flows, which in turn can lead to washing out of soil followed by debris flows and landslides.

Other times heavy precipitation is enough to soak the soil with water, followed by landslides and debris flows without the help of any watercourse.

A combination seems to have created the Boge landslide by Vaksdal near Stanghelle in 2015. This landslide did not only fill up the E 16 road and closed it for some days for clearing up, it also made the Bergen-Oslo Railway Line closed for some days.

The Boge landslide by Vaksdal.
The Boge landslide by Vaksdal.

Also mass movements of even larger scale do occur along the E 16 road. In June 2016 blocks high up in a mountain side were relased, initiating a landslide with blocks, stone, soil, trees and more, finally 100 meters wide when going over the road.

This happened near the road tunnel Hyvingtunnelen to the west of Bolstadøyri. The landslide hit a truck driving on the road. The driver jumped out of the truck, while the truck was caught by the landslide.

The landslide near the road tunnel Hyvingtunnelen. The fjord Bolstadfjorden is seen to the right.
The landslide near the road tunnel Hyvingtunnelen. The fjord Bolstadfjorden is seen to the right.

 

The clearing work is starting.
The clearing work is starting.

 

The landslide widened as it moved downwards.
The landslide widened as it moved downwards.

The roads on the east and west sides of the Sørfjorden tributary fjord in the inner Hardanger are exposed to many mass movements of different kinds during a year.

According to some information, the road on the east side, between Odda and Lofthus, which is a distance of 30 km, have been hit by around 200 rock falls, rockslides, landslides, snow avalanches etc. during a ten year period.

The western side is more known for large snow avalanches. An example, however, of what may happen also on the road on the western side of Sørfjorden, on the Folgefonn Peninsula, is the fall of some large blocks onto the road between Utne and Grimo in April 2018. A car arrived just a few seconds after the fall of the blocks. At the arrival still dust came up from them into the air.

Large blocks fell down onto the road between Utne and Grimo.
Large blocks fell down onto the road between Utne and Grimo.

In the summer of 2017 large amounts of precipitation caused the river in Utvik in Nordfjord, Vestland County, to increase and cause an enormous flow. This flow caused large amounts of soil, stones, gravel, sand etc. to be washed out, creating enormous destruction. The community appeared almost like a war zone.

Some of the results of the flow in Utvik in Nordfjord, Sogn and Fjordane County.
Some of the results of the flow in Utvik in Nordfjord, Sogn and Fjordane County.

 

Snow avalanche in Oldedalen.
Snow avalanche in Oldedalen.

In February 2019 a large snow avalanche went in Oldedalen near Olden in Nordfjord. No one was injured, but a settlement was isolated and for a while evacuated.

These events are some examples of what may happen along roads in fjord areas and adjacent areas in Western Norway. Isolation of settlements, electric power failure, closed roads and evacuation of people are sometimes some of the consequences.

Video about a Snow Avalanche in Gaupne in Luster in 2018

Tribute to the everydays heroes

Let these lines be a tribute to the everyday heroes of the fjord areas and valleys of Western Norway, who live their lives and keep up the local communities under often challenging, difficult and dangerous conditions.

Det Norske flagg. Foto: Christer Hoel.
Photo: Christer Hoel.

 

References

This article is written by Geologist Christer Hoel, M.Sc. – Linkedin