TF1774: Burrard Inlet Batymetry

TF#1774. 2019-06-24.

In the past when I have looked at Burrard Inlet, I have made educated guesses to the underwater topography (bathymetry) of the inlet. Since then, I have been working to complete a full bathymetric map of Burrard Inlet. I am finally done! I have done some work at some crossing options but I'm not finished yet; it's coming soon though

Here are the maps in small size (click the link below it to see a full size that you can zoom into). Each shade of colour is a 5m contour and the topo lines are 1m contours.

Full Size: https://i.imgur.com/OyL80ln.jpg

Full Size: https://i.imgur.com/AiyaqWe.jpg

Full Size: https://i.imgur.com/XmOpj7i.jpg

If you want to do your own your own designs and profiles on top of the topo here are the download links to the Cad files:

Full Inlet Bathymetry and reduced LIDAR above sea-level: https://1drv.ms/u/s!AjWWltw_HSwziLcelq48RitiwTrq3Q

Bathymetry only: https://1drv.ms/u/s!AjWWltw_HSwziLcb6-YiUMFf2FXYbA

I spent $5 on an FOI request to see if the Port of Vancouver would give me any formal bathymetry they had but they denied my request - what you see here took me many hours of researching marine maps and various small snippets of bathymetry data and then digitizing by hand.

Comments

Migrant Coconut: Tidal Scour!
So the depressions are tidal scour, that figures.

Tvisforme: Underwater Bridge?
Is it possible (from an engineering perspective) to have a "bridge" underwater to help level out the path across Burrard Inlet? As in, tunnel down to an appropriate depth and then have an elevated platform supporting the enclosed tracks across the deepest portion of the direct route from Waterfront to Lonsdale Quay? Or would the risk be too great if, for example, a ship was dragging anchor?

waves: Maybe?
I think there are examples of floating underwater tunnels although they are not many. I imagine that a ship dragging an anchor would be very bad. 

scottN: Norway is planning one.
Looks like Norway is currently planning to build the first one, but not in an active harbour. 

cganuelas1995: Would a train derailment be bad?
I'd also imagine the unlikely event of a train derailment would rupture the tunnel.

waves: No. They would be designed for that.
I don't agree. A floating tunnel could easily be designed to handle a train derailment.

Tvisforme: 
Yes, although I was thinking more of a submerged bridge idea rather than relying on buoyancy. Using the depth graphic posted recently as an example, a tunnel would be constructed underground in the blue areas directly in line between Waterfront and Lonsdale Quay, emerging from the white and crossing the black area in the centre on an underwater bridge before going underground again on the north side.

waves: Lateral forces add complication and grades not possible.
If these areas are a result of tidal scour, as Migrant Coconut supposed, then I would imagine that these water depths could see high lateral forces. It also supposes that you can even construct a straight line underground to the tunnel points within the appropriate grades. We already know that you cannot do this from my previous post back in March 2017

scottN: 
The water pressure doesn't weigh directly on the underwater bridge. What it does do is make the immersed tube much heavier than an ordinary bridge deck would normally be. The tube has to be strong enough not to be crushed by the water pressure, and the deeper in the water the tube is immersed the stronger it needs to be. The buoyancy of the tube can be used to counteract the weight of the tube (or nullify it entirely in the floating tunnel design).