People & environment
The construction project is extensive, but only has a minimal effect on the environment and landscape. Lasting environmental impact will occur in relation to the landscape, however the changes compared to the initial state will only be perceptible in the planned increase to the height of the pylons. The heights of 7 pylons will be raised between 2 and 6 metres, primarily in the Alpine region between Leukerbad and Kandersteg, but isolated pylon height increases will occur along the entire line. Targeted measures will minimise the negative impact on the soil, flora and fauna, and the initial state will be restored following the completion of the construction work.
The renovation work will reduce the magnetic field load along the entire line and significantly improve the current state. While operation at 380 kilovolts will increase noise emissions, the measures that have been introduced ensure that the emission limits are complied with across the board.
Restriction of operating current
Swissgrid always observes the statutory limits when constructing lines. The Ordinance on Protection from Non-Ionising Radiation (NISV) is always complied with. Swissgrid also reserves the right to operate the line at the previous intensity of current of 1920 amperes. This is based on the version of the NISV revised in July 2016. Increasing the voltage from 220 kilovolts to 380 kilovolts requires the heights of isolated pylons to be raised, certain foundations to be reinforced and the wire rope hoists to be tensioned in certain sections. These measures reduce the magnetic field without significantly restricting the operating current.