The QLine can't really be expanded into a light rail system, for a few reasons.

The current stations are too small and many of them are in locations where there's not space to make them bigger. Each platform needs to be a few times longer than it is right now, to fit longer trains. And the platforms really need to be deeper, so that there's more room for people to get on and off the trains. When there's crowding at really narrow platforms there are safety issues, and takes longer for people to board. If it takes even 30 seconds longer per stop, it would increase travel times by 10 minutes to Ferndale. The platform depth isn't as much of an issue for neighborhood stations where there aren't going to be a lot of passengers, but many of the current stations are places where you would expect a lot of people to use them.

The current vehicles are street cars and not light rail. You need longer trains with more capacity. You need more doors.

The operations and maintenance facility is too small. It's too small to even use as train storage for light rail trains. And it can't be expanded.

Since you have to move things around in order to get the stations to fit, you'd have to rebuild a lot of the rail itself. There's also the dedicated lanes issue.

And for light rail you would also need to build power substations, which afaik the QLine doesn't have.


So getting the QLine to be light rail would involve redoing it all.

It could be extended as a streetcar short distances though.