The expert group presents its report at a press conference on Monday 12 December at 12.00. – The technical reason for the landslide is work carried out in connection with the new E39 Betna-Hestnes, says Lars Andresen. He is the leader of the expert group and managing director of the Norwegian Geotechnical Institute (NGI). An entire house was destroyed by the avalanche. Photo: Bjarte Johannesen / news The landslide occurred on Friday evening, September 2, in the village of Hennset in Valsøyfjord in Heim municipality in Trøndelag. One house was taken from the earth masses. The 85-year-old woman who lived in the house died. Six people were sent to hospital, including a two-year-old who was rescued from the house. In the area, work is taking place on the construction of the new E39, and work was being done on a construction road a few meters opposite the damaged house when the landslide occurred. Already the day after the landslide, the Norwegian Public Roads Administration confirmed that the construction work could have been the trigger. How the road construction work has been carried out and which safety assessments were made in both planning and implementation have been examined by the expert group. They have also looked at the terrain topography and waterways in the area. The expert group was appointed by the Norwegian Road Administration shortly after the landslide and their report is handed over to the Road Administration, by project director Ove Nesje. – The expert group has done a good and thorough job here. It is important that we understand what happened so that we can learn from it to avoid it happening again. The findings in the report are also in line with the Swedish Road Administration’s own assessments, says Nesje. This is what the landslide area looks like today. Photo: John J. Storholt Do not drill in the area In planning work and risk analyzes ahead of the road work, no pronounced risk of landslides in the area has emerged, nor has NVE marked danger zones there. In geotechnical reports from 2014 and 2020, however, further drilling and test excavations in the area were recommended, in order to get a better assessment of the stability of the ground. Shortly after the landslide, the Swedish Road Administration was able to confirm that such additional ground investigations had been planned, but there was no drilling in the area of the landslide at the time. There are also supposed to have been changes in water conditions in the area ahead of the landslide, and geologists have previously told VG that water going astray could be a possible explanation. A geologist also told news that frequent periods of rainfall lead to an increased risk of landslides, and that this is something that must be taken into account in excavations. The geologist believed that the people should never have been in the house. A few tens of meters above the house that was taken by the landslide, a construction road had been built in connection with the road construction. It is this road that you see in the foreground – in the middle of the picture you see the remains of the house. Photo: Morten Andersen / news Important to learn lessons Mayor of Heim municipality, Odd Jarle Svanem, tells news that the local community is affected by the incident. – This is a small community where everyone knows everyone, so this is noticeable. Svanem says that the municipality has been in contact with both the affected family, the rescue workers, the Norwegian Public Roads Administration and the contractor. His impression is that the Swedish Road Administration and the contractor have taken this very seriously, and the mayor believes it is now important to learn from what appears in the report. – It is important that it is revealed what happened, and what could be involved in causing such a landslide. Learning lessons is important, and in this context, basic research is perhaps particularly important. Mayor Odd Jarle Svanem (Sp) and municipal director Ola Morten Teigen visited the accident site the day after the landslide. Photo: Bjarte Johannesen / news New report before Easter The road work was paused as a result of the landslide, but was taken up again the following Monday. Then with increased geotechnical expertise and geotechnicians on site almost daily. The Norwegian Public Roads Administration has previously stated that routines and choices must be thoroughly evaluated, and that this incident may have consequences for how planning and projects are done in the future. The expert group visited the area shortly after the landslide. The group consists of Lars Andresen (NGI), Anders Beitnes (Faveo project management), Johan Arnt Vatnan (Cajun Management AS), Arnstein Watn (NTNU) and Ingrid Havnen (NVE). Photo: Jøte Toftaker / news The expert group will also prepare a report with suggestions for learning and improvement points. This report must be presented before Easter 2023. The police have also investigated the landslide, but have not yet finished their criminal law assessments.
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The expert group presents a causal report after the landslide in Valsøyfjorden in Heim municipality – news Trøndelag
