What is Water Right?

Legal Definition
Water right in water law refers to the right of a user to use water from a water source, e.g., a river, stream, pond or source of groundwater. In areas with plentiful water and few users, such systems are generally not complicated or contentious. In other areas, especially arid areas where irrigation is practiced, such systems are often the source of conflict, both legal and physical. Some systems treat surface water and ground water in the same manner, while others use different principles for each.
-- Wikipedia
Legal Definition
A legal right, in the nature of a corporeal hereditament, to use the water of a natural stream or water furnished through a ditch or canal, for general or specific purposes, such as irrigation, mining, power, or domestic use, either to its full capacity or to a measured extent or during a defined portion of the time. See Hill v. Newman, 5 Cal. 445, 63 Am. Dec. 140; Cary v. Daniels, 8 Mete. (Mass ) 480. 41 Am. Dec. 532; Canal Co. v. Hess, 6 Colo. App. 497, 42 Pac. 50.
-- Black's Law Dictionary
Legal Definition
The legal right to the use of water. See o Cal. 445, 63 Am. Dec. 140. See, also, Accrued water rights.
-- Ballentine's Law Dictionary
Legal Definition
the name given to the legal right to use water from a stream or lake for your own purposes.