Fortum has now begun work on improving the dam safety at the Lima hydroelectric power station.
Lima is located on the river Dalälven in the municipal district of Malung-Sälen. The Lima power station was commissioned in 1960, and now, after 55 years of operation, it is time to invest SEK 100 million in improvements to the dams to ensure their compliance with today's regulatory requirements.
In 2014, Fortum received an environmental protection order to carry out work at the Lima power station to improve the safety of the dams. After a year-long procurement process, it is time for the work to commence. The measures to be implemented include new erosion control structures, filters and supportive fill material for the earthfill dams. Fortum will also inspect the watertight core of the dam and update the leak detection system
"We have a high level of safety at our hydroelectric dams and we're now taking steps to further improve it. The ongoing climate change means that we must expect to have to cope with higher river flows in the future. The goal of the work is to ensure that the power station can cope with the largest flow that can be expected over a thousand-year period," says Hans Ingfält, who is Fortum's manager for the project.
In addition to this, a new flap gate will be installed in the spillway dam to replace the old timber-rafting gate. The timber-rafting gate will be demolished. The two existing spillways will also be modified and upgraded. Total investment is expected to be SEK 100 million.
"The Lima facilities have played a crucial role in making Sweden a modern, industrialised welfare state by providing households and industries with clean and safe electricity. By modernising the dams, we will ensure that the power station can be part of the new renewable energy system that is now emerging," Hans Ingfält explains.
The work is scheduled for completion at the end of June 2017 and the building contractor is Skanska Sverige AB. The contractor for the new flap gate is Gullängets Mekaniska Verkstad AB in Örnsköldsvik. Mobin Hydraulic in Borlänge is responsible for the refurbishment and upgrade of the existing gates.