The Silver Line launches this Sunday, December 13, and will run from the Artesia Transit Center to the El Monte Station, consolidating a bunch of lines that were running along its route on the El Monte Busway (the 10 HOV lane) and Harbor Transitway (the 110 HOV roadway). The old routes will be renumbered and rejiggered to become local lines connecting to the Silver Line.
Silver gets a color because Metro considers it Bus Rapid Transit, like the Orange Line, but it doesn't have its own right of way like Orange. It has the HOV lanes. The launch this weekend is just Phase One of the plan, though--the eventual idea is for the Silver Line to benefit from Caltrans and Metro's ExpressLanes project, which will convert HOV lanes to toll lanes (Called High-Occupancy Toll lanes, aka HOT Lanes. We're going to have fun writing about those.). The program, scheduled to start a one year trial next winter, will have dynamic pricing, so cars will be charged more when the HOT lanes are more full.
Phase Two for the Silver Line is scheduled for June completion and will include service enhancements on the Harbor Transitway and Park & Ride improvements. Phase Three, scheduled for December completion (just before the ExpressLanes kickoff), will connect the Silver Line to the Patsaouras Transit Plaza at Union Station, give the line signal priority in Downtown, and incorporate 41 natural gas-powered buses.