<P> California recognizes water rights granted to pueblos (settlements) under the Spanish and Mexican governments, prior to the Treaty of Guadalupe Hidalgo . Under the doctrine, pueblos organized under the laws of Mexico or Spain have a water right to the yield of all streams and rivers flowing through the city and the groundwater aquifers lying below . Pueblo water rights are superior to all riparian and appropriative rights and cannot be lost by a failure to assert an interest or use the water . In addition, the pueblo's claim expands with the needs of the city and may be used to supply the needs of areas that are later annexed to the city . Los Angeles and San Diego are the only original pueblos to exercise their pueblo water rights in the courts . </P> <P> Pueblo water rights are controversial . Some modern scholars and courts argue that the pueblo water rights doctrine lacks a historical basis in Spanish or Mexican water law . </P> <P> Under the riparian doctrine, "the owner of land has the right to divert the water flowing by his land for use upon his land, without regard to the extent of such use or priority in time". "Riparians on a stream system are vested with a common ownership such that in times of water shortage all riparians must reduce their usage proportionately ." </P> <P> Riparian water rights were inherited from the common law of England . Under the doctrine, property owners have correlative rights to the reasonable use of the water passing through their land adjacent to the watercourse . The right is part and parcel with the land itself and, in California, only accompanies those tracts that have always directly touched the water . </P>

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