Cal. Harb. & Nav. Code § 663.1

Notwithstanding any other provision of law, a peace officer may, without a warrant, arrest a person who is involved in an accident in the waters of this state involving a vessel when the officer has reasonable cause to believe that the person had been operating the vessel while under the influence of an alcoholic beverage or any drug, or under the combined influence of an alcoholic beverage and any drug.