I’m torn on this. I think there’s a case to be made that we could allow taller street walls than you advocate for. Plenty of older parts of dense US cities have high street walls and narrow streets - and people love them!
I think you need to find me examples we can discuss. Don't get me wrong, there are attractive mews and such...........but, well, lets take this 6M wide street in Boston:
Source:
https://amateurplanner.blogspot.com/2016/02/there-has-been-lot-of-discussion-in.html
The sidewalks are not accessible to those with mobility aids /wheelchairs / strollers. It's too narrow.
There are no trees, and none will grow here, but even if they could, there wouldn't be a road at all anymore.
Toronto Fire would definitely balk.
Is it cute, sure, though I like my trees, but to be clear there are some very real tradeoffs.
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From the same site as above:
ROW has trees, works for me....but, but.....
First, you have a 3-4s street wall and the ROW has now stretched to 11M wide. But notice the sidewalk with trees is again impassable to anyone with a stroller/wheelchair etc. They would have to walk in the street. Now imagine snowbanks.
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I think it's important to find real world examples that aren't simply a postcard, and you then have to find solutions to the challenges I've noted.
Was the increase in cars proportionate to the increase in people? If you increased density by 20% and vehicular traffic by 10% I would…be ok with that. The real question is whether there’s a differential between density increase and vehicular increase, and how much do we anticipate that to be? If each additional person results in an additional car - that’s bad.
LV is an unending traffic jam in rush hours and at other busy times. It's not pleasant for pedestrians or cyclists. I don't think making a community unlivable and hoping people will change their behavior to make it livable is reasonable. We've seen no evidence that that works.
Aren’t the first 3 a function of zoning and what the city compels developers to do? (The employment piece is very very hard)
Zoning can't compel a grocery store, though it may, arguably compel a grocery-store ready space.
A school is a function of setting aside / buying (if necessary) the required land and the province approving and funding its construction (Elementary/HS)
Post-secondary is getting a college/uni to agree to provide a campus, and getting funding for same. (which will not come from the City)
Employment lands are a zoning thing. But, as Scarborough and Northyork DT's have shown, simply mandating the provision office doesn't make it work at any scale.