Phase 1 opened about four years ago with the Milpitas and Berryessa/North San Jose station. Phase 2 will be much more complicated as it requires a subway to be built for three of the stations and will utilize a tunneling method that has been done in the United States. Impact to Downtown San Jose and local businesses should be much less using this method over traditional "cut and cover" subway construction.
The 2nd phase is expected to cost $13 billion and be ready for use in 12 years. The initial estimate was a price tag of $4.4 billion and an opening in 2026. Hopefully there will be some ways to reduce cost and expedite the timeline in the near future.
Source: The Mercury News
Source: The Mercury News