The Karl Prehn was a fireboat acquired by the Portland Fire Bureau in Portland, Oregon, in 1973.
[1] She was added to the Bureau's fleet not long after the Police Bureau's responsibility for patrolling the harbor was transferred to the Fire Bureau.
[1] But, in 1984, the vessel was made available to the city of Lewiston, Idaho.
[2][3] By 1994 Lewiston had purchased the vessel, and was considering retiring her, and replacing her with a more modern vessel.
[4] The ship was named after a former Portland harbormaster, who also in charge of the Mulkey, a harbor patrol vessel.