A short tailrace canal links Sigalda Station with Hrauneyjafoss Station
Sigalda Power station is located just above the Hrauneyjafoss Station, south of Lake Þórisvatn. The station came on-line in early 1978. A short tailrace canal links Sigalda Station with Hrauneyjafoss Station. Sigalda Station was built following the development at Búrfell. Its construction was a race against time as there was great demand for more hydropower stations to satisfy energy requirements in Iceland following the powerintensive industrial growth in Straumsvík and Hvalfjörður.
The Sigalda Dam dams the Tungnaá River at the top of the canyon above Sigalda Hill, where it forms Krókslón, a 14 km2 reservoir. The rock-fill dam is 925 m long, clad with asphalt, and 40 m tall at its highest point. The water is carried 1 km through an intake canal from Krókslón Reservoir to the western edge of Sigalda Hill. Three pressure shafts, 216 m long and 4.3 m in diameter, run to the powerhouse north of the old riverbed, in part buried inside the Sigalda hillside. The harnessed head is 74 m. A 550 m tailrace canal leads from the powerhouse into the Hrauneyjafoss Reservoir.