A remarkable 650 pumps are being rented by Skanska Maskin to contractors working on a massive underground power cable project linking Sweden and Norway.
The €807 million South-West link project, which began in 2012, includes the construction of 250 km of underground transmission lines to connect Sweden’s power grid at Nässjö to the Norwegian grid in Oslo.
The new cable follows the route of old power lines through remote villages and forests, and in areas prone to high rain levels and floods. The project is being implemented by Swedish utility company Svenska Kraftnät and its Norwegian counterpart Statnett.
To combat the high water levels and occasional swamp-like conditions, Skanska Maskin has supplied 650 Tsurumi pumps.
“These projects don’t come around very often,” said Magnus Malmerin, manager at Tsurumi-Intec Sweden, “Using a hundred pumps is quite common but I have never experienced 650 being used on one project before.”
The project requires pipes to be installed in the ground every 30-50 metres along the cable trench, with the pumps placed inside the pipes to lower the water table before cables are installed. Additional pumps are also placed directly in the trench where required. The pumps are powered by movable generators and can be placed anywhere along the line.
“Some water is visible and very close to the surface but even if the ground appears dry, lots of water is trapped underneath”, said Mr Malmerin, “When you start digging, water floods the area, causing a potential safety hazard. Safety precautions are crucial because the transmission cable will eventually be carrying about 1400 MW of electricity.”
There are three different models of Tsurumi pumps being used at the project, the lightweight LB800 and the heavy duty KTV2-22 and KTV3-37 units.