Like most western states, both Idaho and Wyoming regulate water use according to the “prior appropriation doctrine.” The prior appropriation doctrine recognizes the priority of water rights, or the order in time in which they were originally acquired. Early water users are referred to as “senior,” while those who come later are called “junior.” In water-short periods, water users having senior rights can use the water first, before junior water users. In fact, a senior water right holder is entitled to have his right filled completely before any junior right holder is entitled to divert at all.

Idaho and Wyoming consider water to be a public resource to which private rights of use may be acquired. As such, while a water right is a property right, the owner does not own the water itself. The owner merely owns the right to use the water for a specific purpose. Water rights, therefore, are often described as “usufructuary,” meaning a right to use a thing, not ownership of the thing itself. Nonetheless, water rights are a type of real estate and, therefore, may be sold, donated, mortgaged, deeded, and leased.

Each state has specific laws that govern the acquisition and use of water within that specific state. In Idaho, water rights are managed by the Idaho Department of Water Resources (www.idwr.idaho.gov). In Wyoming, this role is fulfilled by the State Engineer’s Office (http://seo.state.wy.us). The websites of both agencies are great resources, and an ideal first stop in the quest to learn more about water rights and water law. For specific information about water rights in Teton Valley, don’t hesitate to stop by our office. We’d be happy to get you pointed in the right direction!

This information was posted on the Friends of the Teton River website. For more information visit their website at tetonwater.org.