Fjergen is a lake in MerÃÂ¥ker Municipality in Trøndelag county, Norway. The lake has a hydropower dam on the southern end which flows out into the KÃÂ¥pperÃÂ¥a river which is part of the Stjørdalselva river system. There is about of water stored in the lake.
The lake is located about north of the village of KopperÃÂ¥ and about northeast of the municipal center of Midtbygda. The lakes Feren and Funnsjøen lie several kilometers to the northwest, and the border with Sweden lies a few kilometers to the east.