Residents in the central Taiwan city are waiting for the service on the Green Line to resume following the discovery of safety issues shortly after it started carrying passengers in November last year, the city's Transportation Bureau said.
Despite that setback, planning on the Blue Line and Orange Line have continued, they added.
The Green Line connects Taichung High Speed Railway Station and two Taiwan Railways Administration (TRA) stations, Songzhu and and Daqing, as well as Taichung City Hall.
The two new lines are expected to greatly enhance the performance of the system.
The Blue Line, which will run parallel to the city's main traffic axis Taiwan Boulevard, will be reviewed by the Ministry of Transportation and Communications (MOTC) that includes an environmental impact assessment, the bureau said.
The 24.8-kilometer line will extend from Taichung Port in the west to TRA Taichung Station in the east, intersecting with the Green Line at city hall, it said.
There will be 20 stations along the NT$128.5 billion (US$4.62 billion) line, which will also pass close to TRA Shalu Station and Taichung Industrial Park, bureau officials said.
Meanwhile, the Orange Line, is at a more preliminary stage but also just finished a feasibility review which will also be submitted to the ministry for approval.
The 29.2-km-long line is expected to cost NT$118.5 billion to build, officials said, and meet the transportation needs of passengers traveling to and from Taichung International Airport.
There will be 26 stations along the line, connecting TRA Taichung Station, Shuinan Economic and Trade Park and Taichung Software Park.
