Metro is set to start on dozens of new transit projects over the next 50 years.

In November, Los Angeles County voters approved a sweeping sales tax initiative to fund dozens of transit projects throughout the region over the course of the next 50 years. Now, Metro is looking to accelerate the arrival of a few of those projects, potentially making them available years earlier than expected.

The transit agency announced Thursday that it would issue requests for proposals from contractors based on three unsolicited pitches the agency received for public-private partnerships that would speed up construction of a transit line through the Sepulveda Pass, a light rail between Union Station and Artesia, and an expansion of the express lane system on local freeways.

The details of those potential partnerships between Metro and private firms are confidential, so it’s hard to say how they might work or how much more quickly the projects would arrive.

When Metro announced it was considering the public-private partnerships earlier this year, County Supervisor and Metro board member Janice Hahn predicted the partnership to accelerate the West Santa Ana Transit Corridor would result in the project’s completion 14 to 15 years ahead of schedule. (Work on the light rail is currently projected to wrap up in 2041.)

Metro CEO Phil Washington has previous experience overseeing public-private partnerships, having negotiated a major agreement as head of Denver’s transit agency with a group called Denver Transit Partners. Under that deal, the privately owned organization will build, maintain, and operate a pair of rail lines with heavy taxpayer subsidies.

What partnership agreements will look like in LA remains to be seen, but city leaders have been optimistic about their potential to quickly expand the region’s transit network.

“By creating innovative partnerships with the private sector,” said Mayor Eric Garcetti in a statement, “we can accelerate Measure M projects, and ease traffic across our region even more quickly than we expected.”