Port of Vancouver Discussion

[MIPS]

A SkyTrain can get away with a grade like the SkyBridge because its propulsion allows for grades in excess of 10% and is helped by it not needing to return to ground level on the Surrey side.
A Diesel/electric combination of any length weighs considerably more and has nowhere near the propulsion to handle much more than a 5% grade.

A replacement rail bridge high enough to clear any cargo traffic is a dream if not because the Thornton Tunnel portal would have to be completely rebuilt to add a grade inside the tunnel to make up for the lack of outdoor grading, which isn't itself possible due to existing structures above it. Your only practical replacement of the bridge is an extension from CP's existing line in Port Moody. You'll never see it. People paid millions for their waterfront views and they'll crucify you, economy be damned.
Hell, the only other connection to north vancouver is through Pemberton and I don't think the old BC Rail line connects to anything on the CN or CP mainlines.