Reservoir

The Reservoir is a location in Luigi's Mansion 3. It is found in the Boilerworks on the second basement floor of The Last Resort, located east of the Waterworks and the Storage Room, west of the Observation, and south of the Main Tank.

There is a motor where Gooigi and suck or blow to move the rotating bridge for Luigi to get to the Main Tank. There's a ladder which Luigi can examine to open the ladder after draining the water and making his way back to the main tank. When revisited, Luigi can launch Toad to open the ladder again.