https://vancouver.ca/streets-transportation/granville-bridge-structural-work.aspx
One might think that the 1950s Granville_Street_Bridge was built with a lot of future capacity in mind.
https://vancouver.ca/streets-transportation/granville-bridge-connector.aspx
At least the bridge started out with 8 lanes, but to put in a good sidewalk & bike lanes, 2 traffic lanes had to be removed. At least with 6 lanes, the G Bridge can still eventually have 2 bus lanes. However, had the original sidewalks been tripled in width, the bridge could have still had 8 lanes. 6 general lanes & 2 bus lanes.
https://granvilleisland.com/news/transportation-updates-on-granville-bridge-city-of-vancouver
Unfortunatly, the Granville+Street+Bridge wasn't designed to have a lower deck for future streetcars or tram-trains, because it didn't seem necessary back in the 1950s. Of course Vancouver & the region never built a series of wide freeways & expressways, so retaining the streetcars & interurban trains would have been a good idea.
Fortunately, the backward Vancouver mentality wasn't able to convince Melbourne to give up on its trams. Imagine if Toronto, Boston, Philadelphia, New Orléans & especially SF gave up on having their streetcars.
Now Vancouver stands to be one of the last major cities & urban areas to bring back the streetcars or tram-trains in the form of modern LRT vehicles.
Express bus lanes or rapid bus right of ways can be very good, but LRT is also a very good transit mode that's in-between a subway or an urban metro train line.
https://jfdatalinks.blogspot.com/search?q=Granville+Street+Bridge