RMtransit has
provided his encyclopedia-esque take on the project. Overall a good overview of the project; it was interesting to hear his breakdown on two 'grades' of high speed. he made an odd projection of a terminus by Government Centre LRT Station. The rest seems pretty logical.
I think a terminus south of Whyte Ave, where the CN yard is, makes the most sense. Some sort of improved transit is coming to Whyte eventually (hopefully both the Gondola and an LRT line, imo) so a station there would have good access to the wider city. I see this as the best option. A second location, in my mind, would be South Campus LRT. the location is decently central, with lots of space to build a station. the LRT, with a grade separation at University Ave and 114th, would be able to get the Metro and Capital Lines into this station and provide good service. not ideal, but better than the Via Rail Hut. There is also a lot of development land at South Campus that would allow the builders, University, and Province to make some money off of. IDK.
I don't see this crossing the river into downtown. the River Valley in central Edmonton, from 116th to 95th streets-ish, is super busy with bridges, crossroads, and heavy top-of-bank development. trying to line things up for a bridge and tunnel, either straight on or curved, would be hugely difficult, expensive, and trigger a lot of environmental review (see what hoops the gondola project is jumping through). Reusing the High Level bridge and its associated ROW would make some sense, but this would involve tight clearances to private property, tight curves, and very little space for a station. even if they bought out and plowed over all of railtown park, it would be tight, and very unpopular. I don't see this crossing the river.