In the second half of the 19th century, the federal government pursued a policy of confining Indian tribes to reservations. These reservations were either a portion of a tribe’s aboriginal land or an area of land taken out of the public domain and set aside for a tribe. The federal statutes and treaties reserving such land for Indian reservations typically did not address the water needs of these reservations, a fact that has given rise to questions and disputes regarding Indian reserved water rights.

Dating to a 1908 Supreme Court ruling, courts generally have held that many tribes have a reserved right to water sufficient to fulfill the purpose of their reservations and that this right took effect on the date the reservations were established. This means that, in the context of a state water law system of prior appropriations, which is common in many U.S. western states, many tribes have water rights senior to those of non-Indian users with water rights and access established subsequent to the Indian reservations’ creation. Although many Indian tribes hold senior water rights through their reservations, the quantification of these rights is undetermined in many cases.

Tribes have pursued quantification of their water rights through both litigation and negotiated settlements. The settlements involve negotiation between tribes, the federal government, states, water districts, and private water users, among others. They aim to resolve conflict between rights holders and allow the parties to determine specific terms of water allocation and use with certainty.

Over the last 50 years, negotiated settlements have been the preferred course for most tribes because they are often less lengthy and costly than litigation. Additionally, many stakeholders have noted that these negotiated agreements are more likely to allow tribes not only to quantify their water rights on paper but also to procure access to these resources in the form of infrastructure and other related expenses, at least in some cases.

After being negotiated, approval and implementation of Indian water rights settlements require federal action. As of 2017, 36 Indian water rights settlements have been federally approved. Of these, 32 settlements were approved and enacted by Congress and 4 were administratively approved by the U.S. Departments of Justice and the Interior. After being congressionally authorized, federal projects associated with approved Indian water rights settlements generally have been implemented by the Bureau of Reclamation or the Bureau of Indian Affairs (both within the Department of the Interior), pursuant to congressional directions. Congress has appropriated discretionary and mandatory funding (and, in some cases, both) for these activities, including in recent appropriations bills.

Several Indian water rights settlements have been considered and enacted, including three that were enacted in the 114th Congress. A primary challenge facing new settlements is the availability of federal funds to implement ongoing and future agreements. Indian water rights settlements often involve the construction of major new water infrastructure to allow tribal communities to access water they hold rights to, and obtaining federal funding for these projects can be difficult. As a result, some settlements have been renegotiated to reduce their federal costs.

At issue for Congress is under what circumstances (if any) to approve new Indian water rights settlements and whether to fund (and in some cases amend) new and ongoing settlements. Some argue that resolution of Indian water rights settlements is a mutually beneficial means to resolve long-standing legal issues, provide certainty of water deliveries, and reduce the federal government’s liability. Others argue against authorization and funding of settlements, either in general or with regard to specific activities associated with individual settlements.

This report provides an overview of Indian water rights settlements. It analyzes issues surrounding water rights settlements and the negotiation process, as well as implementation challenges and related issues for Congress.