Turns out it's not just the cell in 36897. Fixed a TON of floating navmesh, navmesh going through walls, missing dropdown links, etc. Note for arthmoor: I did NOT add the water flag to underwater triangles because I was worried it might affect the escort quest. If you want to add them, go ahead.
Avoided touching the cell already changed in in 36897.

Attached Files:
darkwaterstart.esp