Water Law

The rules that govern the ownership, control, and use of water as a resource are referred to as water law. States typically employ one of two water law doctrines to govern water use: riparian rights and prior appropriation. Riparian rights are generally used in the eastern United States, where rainfall tends to be more abundant than in western states. Riparian rights are linked with land ownership and follow the principal that anyone owning land adjacent to a surface water body is entitled to "reasonable" use of the resource. The prior appropriation system, which is employed in the western United States where water is less plentiful, is often summarized by the phrase, "First in time, first in right." In other words, those that first staked claim to a specific allocation of water have priority over later claims. Unlike riparian water law, the resource is not linked to property ownership. It was created to allow for diversion of water from the source to locations where it would be of beneficial use.