|Location||Near Eiði, Faroe Islands|
|Catchment area||42.6 km2 (16.4 sq mi)|
|Basin countries||Faroe Islands|
|Surface area||47 ha (120 acres) (natural size)|
|Water volume||17,000,000 m3 (14,000 acre⋅ft)|
|Surface elevation||129–149 m (423–489 ft)|
Lake Eiði is located between the villages of Eiði and Ljósá. It is the fifth-largest natural lake in the Faroe Islands, with a natural size of 47 hectares (120 acres) that has been increased to 1.14 square kilometers (0.44 sq mi). The size of the lake was increased by walls 22 and 13 m high, constructed by the SEV company in connection with the Eiði power plant, which uses the lake as a reservoir. Electricity production was started in 1987. Two tunnels redirect water from adjacent valleys to Eiði.