Dereck A. Benitz, 40, of Salem, Ore., was put back in jail after the building's water pressure suddenly fell Wednesday, The Oregonian reported.
Officials found Benitz in the facility's water vault yanking wires from the wall, Cmdr. Jason Myers said.
Benitz was yelling he had "defused the bomb" when officials found him.
Officials said they found no sign of a bomb, but Benitz had shut off the prison's water valves.
Benitz has been charged with first-degree criminal trespass, criminal mischief, second-degree burglary and disorderly conduct for the wire-pulling incident, the newspaper said.