New county road to be secured with radar

The county road is prone to landslides. Seven landslides have been recorded since 2010. In January, the road surface was buried under heavy snow.

The client is Nordland County Council. The avalanche warning system must be established before 1 February. Next winter, it will also have automatic road closure with a lighting system.

The facility will be the fifth avalanche monitoring centre established by Cautus Geo in Norway. In addition, Cautus Geo has delivered systems for continuous monitoring of avalanches in Iceland and Austria.

Closure lighting system

- "The warning system will be fine-tuned this winter. Then Nordland County Council will connect the lighting system next winter," says CTO Lars Krangnes of Cautus Geo.

The radar will be established on the south side of Beisfjorden, in an area without electricity. From there, it's 2.5 kilometres to the mountain peak where the landslides are triggered, called Moskochokka at 1,350 metres.

- "We solve the lack of power with a special solution. It combines a solar cell and a generator that charges a large battery pack to supply the facility with electricity throughout the winter," says Krangnes.

Safeguarding life and health

- We want to safeguard life and health. 950 cars pass Blomlia every day. Almost 700 residents have the road as their only connection. If the road has to be closed, the alternative is boat transport on the fjord when it's not covered in ice. An additional disadvantage is the lack of a quay," says geologist Sølve Ustøl Pettersen of Nordland County Council.

Blomlia is also prone to landslides, rockfalls and icefalls. Landslides also occur elsewhere along the fjord. They generally do not reach the road surface.

Six avalanches have reached the road since 2011. Four are avalanches.

Avalanches that reach the road can cover 250-300 metres. There, cars pass at 80 kilometres per hour, which is the speed limit.

Large landslide in January

In January this year, the largest known avalanche ever hit Blomlia. Large trees snapped like thin matches. A quarter of a kilometre of road was buried under heavy snow.

Other parts of the county road along Beisfjorden are also at risk. There, landslides come thundering down from a height of around 1,050 metres, but mainly stop above the forest line.

Twice in the last 50 years, other landslides have reached the road.

- This happened most recently in January this year at inner Olderneset," says Pettersen.

More open roadway

- Establishing avalanche warning systems will increase safety and reduce long-term road closures. There is still a residual risk. It's linked to other exposed parts of the road. In that case, we may have to close the road and consider triggering avalanches manually," says Pettersen.

The plant will be in operation this year.

The signalling system will be in place next winter.

- The roadway can then be closed and reopened automatically if the landslide masses do not reach the road," says Pettersen.

Climate change increases the risk

More landslides are likely in the years to come.

- This is due to climate change. This may result in periods of heavier precipitation in terms of intensity and frequency," says Pettersen.

This year's January avalanche took one minute from the top of the mountain. Calculations show that snow masses can fall at a speed of 33 metres per second.

- Even snow ploughs travelling at 40 kilometres per hour, which is the optimum speed for efficient snow removal, will be protected by the placement of the traffic lights," says Pettersen.

The delivery includes:

• Radar system
• Camera system
• Subject support system
• Local power supply
• Necessary infrastructure for the operation of the detection system, such as foundations, masts, fasteners, weather protection and internet connection.
• Interaction with supplier of signalling systems
• Forest clearing for visibility and access
• Shipping and installation
• Down-rigging
• Drift

Radar to warn of landslides to

• Signalling systems
• Camera system
• Supplier database (Cautus Web)
• TEXT MESSAGE
• E-mail address
• RegObs
• Natural hazard portal