What term describes the right to use water in a river or stream?

The term that best describes the right to use water in a river or stream is "Riparian Rights." This principle grants landowners whose property is adjacent to a flowing water source, such as a river or stream, the right to access and use the water, as long as it does not significantly affect the rights of other riparian owners upstream or downstream.

Riparian rights typically include the use of water for domestic purposes, livestock, and irrigation, while ensuring that the water is used reasonably. This concept is based on the idea that water naturally flows and should be shared among users in a manner that protects the interests of all those who have claims to it along the watercourse.

In contrast, littoral rights pertain to properties that abut large bodies of water, such as lakes or oceans, focusing on the ownership rights of landowners along these shores. Other options, like surface water, refer more broadly to the water on the surface of the land, while the rule of capture relates to the extraction of water from groundwater sources, and does not pertain to flowing water like rivers or streams.