I think this is a valid question to ask Metro to clarify… I think the preliminary documents seems to suggest their preferred routing is the one I described rather than the one Jerard mentioned.

Personally, my bet is on running service like this;
A)Expo-Pasadena and
B) Long Beach-East LA.

Because the Pasadena and Expo lines will need a transfer at Union Station to connect Metrolink riders to destinations along each route (Pasadena, USC, West LA and Santa Monica; when Expo is completed). The Long Beach-Eastside alignment I feel is more dependant on a connection at 7th Street Metro Center for the most ridership and may not see a lot of ridership towards Union Station.

Yes, exactly what I was trying to say but in a much long winded way…

After completion of Downtown connector, at 7th St Metro Center, the Pasadena-Long Beach and East LA-Culver City train will indeed form an X pattern as Jarrett suggests. But for some reason, he thinks the “X” needs to be at Union Station. That’s ok in theory… but in practice (and in planning for the future), the local transit movements converge in 7th St Metro Center. It’s going to be much more important transfer node than Union Station.

In Downtown LA the current and future rail lines follow a “C shaped” pattern. From the Civic Center to the South Park area down to either Figueroa or Broadway corridors. But look closely when the connector is built an X is formed at one central point, 7th Street/Metro Center. Thankfully that is where the X makes the most sense.

It would have been nice if the original Red Line subway had four tracks in it’s Downtown portion to allow these trains to go through, but alas that wasn’t the case. But this will still do the job quite well when it’s all built.

And the reason it is not a big deal is because Expo line will intersect with the Red/Purple line subway at 7th St Metro Center… LA’s de facto “Penn Station” if you consider Union Station to be our “Grand Central”. At 7th St Metro Center, the very few East LA riders that want to go to Union Station can change train and go “backwards”. The majority will either stay on Expo to Santa Monica, or they will transfer to the subway to either North Hollywood or Century City.

Why isn’t there demand for people from East LA to Union Station? Well, the fastest way to get to Pasadena from East LA is not through Downtown… This is the reason why Metro itself is projecting very low ridership for people raking the Gold line from East LA to Pasadena under the current configuration. Most people will board the trains from Pasadena or East LA and end their trip in Downtown. Granted in the future when CA-HSR is up and running, there may be more significant demand for East LA to Union Station but it is still going to be vastly out numbered by the East LA to West LA movements.

I think it makes sense to see the Gold Line keep running for the reasons you pointed out — that people need to be able to transfer. L.A.’s existing frequencies on the Gold Line are relatively low, so this isn’t technically impossible — you could have 2 Expo or Blue and then 1 Gold every ten minutes (18 trains/hour). But the real question is whether ridership will stand up. L.A.’s transit system probably needs to mature and expand before it makes sense to keep the Gold Line running at high frequencies — and that might happen by the time this thing opens in 2017.

I do wonder, though, if this problem could be solved simply by adding a stop south of Little Tokyo for Expo Line trains if the X formation is used and the Gold Line is canceled. Riders would simply have to walk around the corner to the Blue Line stop, and voila, transfer between the lines.