I don't know if this has been discussed yet on the site, but every time I return to St.John's, I am haunted by the MASSIVE parking wasteland to the South-West of the harbour currently being leased to Oceanex (as far as I know). I don't know when the contract expires, hopefully soon - this is prime real estate. In this area, we could develop a whole new downtown district, so that we can simultaneously maintain our historic downtown (to a certain degree) while building up our new downtown. A number of Cities have down this, particularly European ones. Quebec City is a great Canadian example.
We could liberalize height rules here and build high. Not to mention this area is in pretty rough shape and if planned correctly with some rent controlling we could begin to gentrify this area while keeping it affordable for the folks who live around there.
The City would lost business revenues from Oceanex but personally I believe that the benefit of having a huge new area of the downtown to develop is more valuable than the lost revenues. Plus, about 10 years ago, I remember Oceanex intimidated the City into giving them a cheaper lease as they threatened to pull out of the City and relocate to another nearby Harbour. The City was in rough shape economically and couldn't really afford to lose them so they were taken advantage of by Oceanex. More importantly, if Oceanex was to stay, there is NO WAY that they need that huge amount of land simply to park imported vehicles. This is the most impractical and ridiculous use of valuable downtown space I can think of.
Not to mention - IMAGINE the amazing experience of coming into the downtown along Pitts and there are high-rises while you're already about 8 stories up. It would be a pretty memorable/cool experience. There are similar experiences when driving into downtown Toronto.
This area would also, as it is untouched, provide for a grid style downtown about 6-7x3 blocks in a grid formation. So to answer the earlier question about a new mall - I would build it here.
This is the site I am talking about
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