During the first half of October, the ground collapsed under the historic Gruvebadet building in Ny-Ålesund. The reason was a melting of what are known as ice lenses, resulting in kettle holes, according to a report by geologist Sverre Barlindhaug. Parts of the building, currently used as a research station, were hanging in thin air and the building was in danger of sustaining major damage.
Lots of warmth
"The meltwater has a lot of warmth in it and that is what has led to this happening," Barlindhaug said til Svalbardposten.
The geologist said the kettle holes arose because there has been excavation in the area of Gruvebadet. As a result, water drained along different paths than previously and thawed the permafrost. In addition, drainage from the main flow resulted in a concentration of water in the ground under the building. Eventually the runoff reached down to the ice c ps that melted and resulted in the sinking of the foundation.
Barlindhaug's conclusion is that, in addition to repairs, the foundation material needs to be exchanged for firmer materials that can be built up under Gruvebadet to ensure water doesn't deteriorate the foundation.
Now he's warning several other incidents were apparently the result of drainage and construction errors.
"Having a dump under the building I would say is a design error"
Ice caps are common within moraine masses. During construction of the Svalbard Global Seed Vault such caps were found four to five meters down the hillside. The caps were up to two meters in size.
Many of Svalbard's buildings are on such masses and Barlindhaug said there may eventually be numerous instances where the ground becomes unstable or yields because of meltwater. Measurements also show there has been more rainfall in Svalbard in recent years.
In addition, construction defects are creating problems, he added. Many buildings in Longyearbyen and Ny-Ålesund trap water underneath and therefore it is not redirected away. Furthermore, there are trenches that resulted in a concentration of water in the ground.
"What you should have done is to have raised platforms under the buildings so that all the melted snow drains away and avoids decay," he said. "When water flows away, it also avoids ground thawing."
Does Barlindhaug believe there have been construction errors?
"Yes, I would say that it is a design fault," he said. "Having a dump under the building I would say is a design error. But we were not aware of this before."
For the unfortunate, there are ice lenses in the ground under their buildings. The third factor that will affect structures, he said, is buried pipes and cables. The heat from these can ensure meltwater finds new paths into the permafrost.
Barlindhaug said he is also unsure how steel pilings will work if there is more moisture and rainfall infiltrating.
In Longyearbyen, building owners are discovering wood pilings need to be replaced because they're rotting. Barlindhaug said he believes it's unlikely the decay would have occurred if foundations of solid mass were under the buildings.
Longyearbyen's municipal government has not experienced any foundational failures, but is among those who have noted the consequences of moisture in pilings under buildings. In 2012, an inspection to determine the state of selected buildings was made under the auspices of Mycoteam, which specializes in decay and moisture damage.
Decay was discovered in pilings under several city buildings, the worst of which was was at two townhomes in Funksjonærbyen. These buildings are now condemned.
Dag Arne Husdal, an operations engineer, and Marius Larsen, the project's manager, said they believe they have good control of the situation.
"We have done a thorough investigation and evaluation report on our buildings," Husdal said.
Both said the preliminary investigation of existing foundations was thorough and that pilings today are as deep as the geology requires. In addition, steel pilings are more common.
The lessons learned from replacing pilings was there are broad local fluctuations, but that rot and damage occurred in the transition between the frozen ground and air.
"We have several houses that need to be protected," Larsen said. "It becoming more of a continuous maintenance."
Pipes and cables in Longyearbyen are insulated to prevent heat being emitted, according to the city.
"Here we have complete control"
Going the opposite way
While the city is installing new pilings under buildings with decay, Spitsbergen Travel is taking a different approach by using technology from the Canadian company Triodetic when the tourism company's buildings gets new foundations.
Three barracks in Nybyen will get "floating" foundations, with the company awaiting approval from The Governor of Svalbard and the Longyearbyen Community Council for two more. In addition, the new terrace around the Radisson Blu Polar Hotel will have its foundation replaced using the same method.
Steinar Hegle, Spitsbergen Travel's technical manager, said they haven't experienced changes in the ground surface, but is confident there won't be problems.
"In this case, the whole reason is in accordance with a long-term plan," he said. "Here we will have complete control."
According Hegle, the new foundations have a lifespan of 60 years. Company officials visited northern Canada to look at a building that has stood on such a foundation for 25 years.
Translated by Mark Sabbatini