The initial 13.1km 11-station phase will link Mill Woods Town Centre with 102 Street in the city centre and is initially expected to carry around 31,500 passengers per day.
The $C 1.8bn ($US 1.29bn) project is being implemented by the TransEd Partners consortium of Bechtel, Bombardier, EllisDon and Fengate Capital Management under a design-build-operate-maintain finance contract which reached financial close in February.
Commissioning is scheduled for 2020 and future phases will extend the Valley Line to Lewis Farms to create a 27km line with 28 stations carrying around 100,000 passengers per day.
