This might help even though it is 2011 for the Burbot. I had to link it, because it is too large of an image.
https://backcountrynetwork.files.wordpress.com/2011/01/burbotmap.jpg
Trolling for Mac's is done at the gorge, but jigging produces more frequently.
A few spots where I ice fish, would be an interesting trolling expedition especially if the fish are near the bottom.
I remember one hole would be at 100' and the hole ~5 feet closer the shore being 70'. Just a massive drop off and it would make it rather easy to get your lure snagged if you inadvertently moved to the on the wrong side of the drop off.
I'm pretty sure some areas are like the rocky mountains under the water.