Hello, as explained on another thread I just got back from another 4 weeks in Japan, where layers are nothing to be afraid of.
In cities with growing population and restricted geography (sounds a lot like Vancouver) layers become a necessity to keep surface areas prime for pedestrians and bicycles.
I dont feel like going on a big rant, I just feel like posting a couple pictures i took.
These two pics are the same spot and show a very common scene in Osaka. 3 layers, on the surface we have a relatively calm street with lots of pedestrian activity, above that is a metro line viaduct (akin to skytrain) and above that is a highway viaduct (where all of the trucks and through traffic goes). This is about at 11 at night on a weekday.
It makes a very interesting urban streetscape and there are still shops and tall building built right to the guideway's edges. During the day and the weekend this place is crazy busy with people.
And here is one that shows how commercial units can be built right into a road viaduct. Here, the viaduct is no more intrusive than any other row of buildings. It is not just one store, but an entire row of stores that goes about 200m to the next cross street.
And here is the bullet train guideway. If anywhere in NA wants true high speed rail, these trains need to be 100% separated from any cross traffic, meaning they have to run elevated or in tunnels in urban areas.
Japan is an area of amazingly functioning cities is such small places. Vancouver may be small in comparison, but downtown does exist on a small peninsula with very little land access to the rest of the region, making layers a little more important in our situation then other cities of similar size. it is amazing to see true functioning cities, with true commercial and entertainment zones, and low income people still able to afford condos downtown. I fear vancouver's idea of "livability" is far to geared towards the high middle class vacation condo group and making every corner of the city residential. True live work cities still have some defined areas for work and fun, with residential areas built very near by. Not always mixed.
The viaducts give us a chance to have a unique neighbourhood in the city that maybe all can afford to live in. it also gives the chance to build a unique e entreatment district as well (the stadiums are a perfect start).
But I still like Allan's idea of mitigation. Tear down 1 and retro fit the other into 4 lanes. There is no limit in option to build in that area while retaining 1 (or both) of the viaducts.
Just though I would share those.
All the photos are mine.
Cheers!