I've been to Blackreach before this quest and it was glitchy for me then too, but I'm doing Elder Knowledge looking for an elder scroll and when I get to the section where this tower of Mzark should be there is nothing. It's clearly a glitch as there is nothing but the bare ground all around me and I can hear sloshing water but I can't see the water I'm in. Anyone else run into this or know how to fix/get past it? I've reloaded a bunch of saves before this part. When I get to this area I always encounter this glitch. Pretty upsetting considering it's the main quest.

Are you below the floor? Try using tcl if you somewhere you shouldn't be or if the models really are not loading then the installation/graphics/etc. might be messed up. What happens as you approach the tower?

If you want you can try coc TowerOfMzark which will warp you directly to the puzzle (Unless there are no models there either at which point something is broken).

Thanks for the response. As I approach the area where the tower should be, there is just nothing there but bare land all around. The quest marker is hovering up above a hill and I can't get up there. I hear water but don't see any. I'm not below the floor... I'm on it. I'll try that coc TowerOfMzark command.

You may also might just be approaching the tower from off the beaten path but I don't remember the layout of the area but you could also try walking around this hill from a different approach which might put you back on the right path. If you use the coc command you can also just walk backwards out of the tower to were you were before and that will also probably show the path.

I gave up for a while, but I just loaded up a save again and this time the tower is there. Right on top of the hill I was looking at before. I didn't do anything different but I guess my problem is solved. I saved inside the tower and the game crashed. I was able to load the save and continue though. I love Blackreach, can't wait to get away from it though to avoid anymore glitches.

Probably just a random bug with the game not loading things properly does steam verify all the data files as ok (This usually doesnt do anything anyways though). The worst I have seen in my game is textures randomly not loading properly or the water getting scary looking with its reflections going insane.