TAMPA (CBS4)- A California man has pleaded guilty to dropping an anchor on a Tampa-bound cruise ship.

Federal prosecutors in Tampa said Friday that 45-year-old Rick Ehlert pleaded guilty to one count of attempting to damage a maritime facility. He faces up to 20 years in prison.

Authorities say the MS Ryndam was traveling from Costa Maya, Mexico, to Tampa on Nov. 27, 2010. A surveillance video shows Ehlert entering a restricted area and dropping the 18-ton stern anchor.

When confronted by authorities, Ehlert told them he was drunk at the time. He also said the cruise ship’s anchor system was similar to the system on his own 50-foot boat.

Investigators say the Holland America ship avoided damage because the anchor didn’t hit the sea floor.