Property law (2022): Related topics: Water rights + Prior appropriation + riparian rights (Part Two)

Prior appropriation adoptions.

Alaska, Arizona, California, Colorado, Hawaii, Idaho, Kansas, Montana, Nebraska, Nevada, New Mexico, North Dakota, Oklahoma, Oregon, South Dakota, Texas, Utah, Washington, Wyoming all use the prior appropriation doctrine, with permitting and reporting as their regulatory system. Much of the prior appropriation doctrine in the Southwest and Western U.S. states are a legacy from the area being under the civil law systems of Mexico and Spain, where prior appropriation is heavily practiced.

California and Texas recognize a dual doctrine system that employs both riparian and prior appropriation rights. Oregon mainly uses the prior appropriation doctrine with some remnants of the riparian doctrine. Landowners have rights to water on their own land at a certain time at which it is then incorporated into the appropriation system.

In these cases, riparian rights take precedence, unless they are not claimed by a certain date or are not used within a certain number of years.

Eight states engage in prior appropriation while not recognizing the riparian doctrine: Arizona, Colorado, Idaho, Montana, Nevada, New Mexico, Utah, and Wyoming. 

Arizona adopted the prior appropriation doctrine such that a person could acquire this water right simply by applying it to beneficial use and posting an appropriation notice at the point of diversion. Arizona Revised Statutes Annotated § 45-141 Waters (2021). On June 12, 1919, they enacted the Public Water Code in which the person must apply for and obtain a permit for water use.

However, prior appropriation does not always determine water allocation in these states because the Secretary of the Interior can allocate water without worrying about senior and junior appropriators. Arizona v California (1963).   For example, the secretary of the interior has the power to allocate and regulate water for the purpose of conserving water and wildlife. 43 Code of Federal Regulations § 427.1 Water Conservation (2008).  Such regulations could limit a senior user's water use.

Various federal regulations can also have priority over senior users. For example, the Endangered Species Act of 1973 seeks to protect animals at risk of extinction, so a senior user's rights may be restricted in favor of federal regulation protecting the habitats of endangered animals. 16 U.S. Code § 1531 Conservation (1973).