When players first enter the Sluice-Gate Puzzle Room, they'll see two round valves. The one on the left is labeled Water Level Valve, and the one on the left is marked as the Water Temperature Valve.

There's also a sluice valve to the left, which requires you to pass an Athletics check. We've tried this with a 20 STR companion, but it didn't work. Sewer Battle: How to Keep Minsc Alive ...