California Code, Government Code - GOV § 171

All waters between the mainland and the outermost of the islands, reefs and rocks along and adjacent to the coast of the State of California from which the boundary of the State is measured, and all waters between the islands, reefs and rocks themselves, are declared to be and to have been in the past inland waters of the State. Similarly, all waters within the lines around harbors and across bays, from which the boundary of the State is measured, are declared to be and to have been in the past inland waters of the State. These waters are “waters thereof” within the meaning of that phrase in Section 25 of Article I of the Constitution.