Puzzle:Sewer Flushing Line

Mark leaves the bunker through the vent, and arrives to the sewer. but...

Problem
The flushing line endlessly floods the room with sewage. The door leading out of here is locked.

There is 2 solution

Solution 1
Go down and close the flushing pipe (center). This will let the sewage to mix with the drinking water.



Solution 2
Open the water district pipe.



Then grab the handwheel from the sewer district pipe (falls out when tried to rotate),



put it in the other flushing tube (sewer) pipe,



Close it!



Close the water flushing line (other one)



And now you can leave!