California Water Rights Primer
Illustration of a gold mining claim in the Sierra Nevada.
Society grants property owners rights to use water, not to possess or hoard it. That’s because water is both a basic necessity of life and essential to all economic activity. Legal water use also entails specific obligations. Water rights holders must not adversely affect the rights of other legal water users or harm the environment.
Water shortages make the obscure issues of water policy and law a public concern. It is an adage among water law attorneys that water rights become social policy during droughts.
Water rights vary by state. In California, there are multiple varieties of water rights, including:
To identify water rights holders in individual California watersheds, go to the State Water Board’s EWRIMS database. (Note: Groundwater user data is not available.)
(You may use this link to subscribe to email notices from the State Board to stay abreast of Board business. Just go to the bottom of the Water Rights Info page where you can see in their left margin an "Email Subscriptions" link.)
The California Supreme Court has established that riparian rights holders have priority for diverting water over most if not all appropriative water rights holders. Appropriators may only divert water that is “surplus” to that diverted by riparian right holders from any given stream. Further, there is a seniority system in place for appropriative water rights holders. Those with rights resulting from pre-1914 filing claims have priority over all other appropriative rights holders for diverting and using water. Until recently, their rights have not been subject to review or action by the State Water Board.
Confusion over water rights prevails in many California watersheds; few rights holders know the scope of their entitlements. This can lead to conflict and litigation between neighbors and/or large water users seeking water from the same watershed. In some rivers, streams, and groundwater basins, such conflict has been resolved through “adjudication.” This entails a judge reviewing all available evidence, then issuing a decision that allocates water among the various rights holders in a given watershed or groundwater basin. While adjudication has proven effective in resolving water conflicts, it is expensive and can take many years.