Although a different statute applies, the offense of boating under the influence is pretty much the same as a vehicular DUI. The California Harbors and Navigation Code section 655 applies:
(b) No person shall operate any vessel or manipulate water skis, an aquaplane, or a similar device while under the influence of an alcoholic beverage, any drug, or the combined influence of an alcoholic beverage and any drug.
(c) No person shall operate any recreational vessel or manipulate any water skis, aquaplane, or similar device if the person has an alcohol concentration of 0.08 percent or more in his or her blood.
(d) No person shall operate any vessel other than a recreational vessel if the person has an alcohol concentration of 0.04 percent or more in his or her blood.
The penalties are very similar as those of vehicular DUI. One thing to remember, a boating under the influence (BUI) conviction will count as a prior conviction for purposes of subsequent vehicular DUI. You may also want to read how to conduct yourself during the initial stop by the police on the water ways (Click Here). Same advice can be given to those stopped by a police on water or a highway. (Click Here). Please speak with an experienced criminal defense attorney. BUI is a serious offense just as a vehicular DUI. As always, stay safe on the water and have a designated boat operator.