 The new Metro Line, a branch of the existing Capital Line, opened in September 2015.The separate Valley Line, currently under construction with its first phase due to open in 2020, will use low-floor vehicles.In 2001, to supplement its bus rapid transit (BRT) system, Ottawa opened a diesel light rail pilot project, the O-Train, which was relatively inexpensive to construct (), due to its single-track route along a little used freight-rail right of way and use of diesel multiple units (DMUs) to avoid the cost of building overhead lines along the tracks.