Lesedauer: Berechne...
The municipality of Östersund installed a water pipeline with a total distance of about 8 km between the old ferry ports in Frösön and Sunne in the first half of 2023. A complex project, as the pipeline had to be laid through the completely frozen Lake Storsjön. The pipe system used was the Extena pressure pipe made of polyethylene PE 100-RC, which has also been approved according to DK-VAND.
“This project was truly special because we had to lay a pipeline through the ice, which placed higher demands on us as a contractor.“
Johannes Håkansson, contractor Jämtland UV
Decisive factor: wheather conditions
In addition to precise planning, the time factor also played a major role, as the ice break-up took place unusually early this year, on 27 April. Accordingly, the laying of the pipeline had to be completed beforehand. The construction company Jämtland UV relied on Extena pressure pipes made of polyethylene PE 100-RC, SDR 11 for the implementation of this ambitious project, which was completed exactly on schedule with the connection of the land connections in June.
During dry periods, the municipality of Östersund has recently been unable to supply the areas in and around Fannbyn and Orrviken with sufficient drinking water. That is why a new water pipeline had to be installed to connect these places. “It was important for the municipality of Östersund that the pipes we used were — in addition to all common approvals — also approved according to DK-VAND. This is to ensure that all requirements for drinking water pipes will be met”, according to Johannes Håkansson, contractor Jämtland UV.
DK-VAND is a product certification system to ensure that certified products meet the strict requirements set out by the Danish Ministry of Environment and Food’s regulations and additional requirements for pipes intended for drinking water. That there are no substances in concentrations that could be hazardous to health in pipes used for the distribution of drinking water. So far, there is no equivalent to the Danish DK-VAND in Sweden. Therefore, pipes are certified against the Danish DK-VAND, in Sweden as well. All pipes manufactured by Extena have been certified according to DK-VAND.
Spectacular installation through ice
As the pipeline had to be installed on the bottom of Lake Storsjön, it was first welded on land, then pulled onto the ice, weighted and filled with water to facilitate making it sink to the bottom. The last step was undoubtedly the most exciting one: after a narrow channel had been sawn into the ice along the pipe, the finished pipeline could be lowered through this opening to the bottom of the lake. The pipeline had previously been examined for possible risks of damage to the pipes and prepared accordingly.
“It was important that the pipes had minimal ovality, which is one of the prerequisites for us being able to generate good and secure joints. Moreover, it was important to choose a reliable pipe supplier to ensure that delivery takes place on time, which is especially important in larger projects, thus increasing certainty for us as entrepreneurs”, according to Johannes Håkansson, contractor Jämtland UV.
Project data
| Project description | Installation of a new drinking water pipeline between the old ferry ports in Frösön and Sunne (Sweden) |
| Challenges | Installation on the bottom of frozen Lake Storsjön |
| Solution | Extena pressure pipes made of polyethylene PE 100-RC, SDR 11 |
| Installation | Welding on land, lowering of pipes to the lake bottom through a channel sawn into the ice |
| Pipe system | Extena pressure pipes made of polyethylene PE 100-RC, SDR 11; dimensions: ø 160: 1.800 m, ø 200: 7.200 m |
| Parties involved in the project | Client: Östersund Municipality Construction company: Jämtland UV Pipe supplier: Extena AB |
| Approvals | Nordic Poly Mark (Nordic quality mark) DK-VAND (Certification by the Danish Ministry of Environment and Food) FI (Certification by the Finnish Ministry of the Environment) |
Thomas Nordin
Sales Director, Extena AB
Tel. +46 7052 33373
tomas.nordin@extena.se
