Water information a
Building an impressive tunnel
In the new proposal, Lake Autajaure was spared from regulation. Instead a tunnel was to be built from Lake Sitasjaure, leading the water to the power station. The construction of the tunnel was one of the most ambitious rock excavation operations in Sweden at the time, with the volume of excavated rock amounting to 2.5 million m3. The final stretch of the tunnel has impressive statistics: 16.3 kilometres in length and a width and height of 11 metres each. The machine hall was excavated 160 metres below ground level and had the largest unit in the whole of the Lule Älv River at the time.
Another breakthrough in conjunction with the construction of the Ritsem power station was the use of advanced drilling technology. Pneumatic drills were being replaced by hydraulically driven drills, reducing the problem of oil mist and increasing efficiency. Furthermore, hand-held drilling was replaced by mechanical drilling. For the first time ever in Sweden, they used a so-called full-face assembly for a power plant.
Characteristics of the Lule Älv River
Hydro power is a reliable, safe and renewable source of energy. Today, hydro power accounts for nearly half of Sweden’s total electricity demand. The Lule Älv River, by which Ritsem is located, is Vattenfall’s and Sweden’s most important river for hydro power generation.
When Ritsem Power Station was commissioned in 1977, it was the last facility to be commissioned in the Lule Älv River.