The Alta Power Plant's dam, by Sautso, is one of the tallest arched dams in Norway. The dam's arched form and upper termination into the mountainside is quite an impressive construction. It is a massive, double-curvature arched dam. The crown of the dam is roughly four metres wide. From the top, one has a magnificent view to the north down the canyon and southward of the elongated lake Virdnejàvri. From the base of the dam (at the bottom of the canyon) to crown of the dam it measures 110 meters.

The power plant is comprised of an intake hopper, intake point, dam with a flood diversion structure, water channels and the actual power station. In the last half of the 20th century, power stations, such as Alta, were often constructed into the sides of mountains on stable bedrock. These types of power stations are nearly "hidden" from sight. From an opening in the mountainside, one enters the power station through a tunnel. At the start of the tunnel, the entrance is marked by a portal building with premises serving various purposes. At the Alta Power Station there are two portal buildings, one located at the power station itself and one at the crown of the dam. Both the portal buildings and the power station hall were designed by the architect Egil Sorteberg.