The initial phase totals 9.6km and comprises the Green Mountain Line, which will link Hongshulin station on the Taipei Metro Tamsui Line to Danhai New Township with 11 stations, and a three-station branch to Danshui Fisherman's Wharf, which will be known as the Blue Ocean Line. The $NT 12.8bn ($US 439m) project is due to be completed in 2018.

A second phase totalling 4.4km is also expected to open by 2023, and the network will have capacity for around 120,000 passengers per day.

The CEPD previously considered extending the metro to Danhai before adopting light rail as its preferred option.