Section 6204 Of General Provisions From California Harbors And Navigation Code >> Division 8. >> Part 4.

. If any land under a navigable stream is by virtue of any work or improvement by the United States or the State, freed from the easement of navigation and fishing, it reverts to the district, to be used for the purposes for which the district was organized. But if any land is not used or held for such purposes, it reverts to the State.