Work is done to clear the Plum Brook water pumps of debris.
In this historical photo from the U.S. space agency, a diver emerges after working on the Plum Brook water pumps in Lake Erie. Divers had to flush the intake line and clear it of mud, silt, and debris regularly.
For more information browse the Plum Brook Facility Page.
Each weekday, SPACE.com looks back at the history of spaceflight through photos (archive).