Riparian, << rih PAIR ee uhn, >> rights are the legal rights of a landowner whose property borders or forms the bed of a stream or river. Each riparian owner has a right to have access to the stream and to use or consume the water reasonably. In many jurisdictions, the owner’s permission is required for any increase or decrease in the flow, any move to change the flow’s direction, or any action that would make the water dirty. The owner may own the land extending to the center of the bed of a nonnavigable stream, or only to the ordinary high-water mark along a navigable stream or lake.
In Western states with scarce water supplies, riparian rights to consume water are either limited or do not exist. In these states, reasonable use of water by riparian owners has been replaced by the right of prior appropriation. This right gives legal use of the water to the person who takes it first. Other people may use any remaining water.
