Work began on the SKr 645m ($US 77m) project in December 2013 and involved the construction of 10 new bridges, including a 200m-long structure which carries the line across Harnäs Bay.
The new alignment is designed for 200km/h operation and the line will be used by around 112 trains per day, comprising 40 passenger trains and 72 freight trains.
The completion of the Skutskär - Furuvik project leaves just one remaining section of single track on the East Coast Line between Stockholm and Gävle. Track-doubling on the stretch through Gamla Uppsala is due to be completed in autumn 2017.
