Fjergen is a lake in the municipality of Meråker in Nord-Trøndelag county, Norway. The 14.41-square-kilometre (5.56 sq mi) lake has a hydropower dam on the southern end which flows out into the Kåpperåa river which is part of the Stjørdalselva river system.The lake is located about 5 kilometres (3.1 mi) north of the village of Kopperå and about 7 kilometres (4.3 mi) northeast of the municipal center of Midtbygda.