Reserved rights & water law

Reserved Water Rights

What are reserved water rights? When the federal government reserves public lands for particular purposes — Indian homelands, wilderness preservation, multiple-uses in national forests, parks, monuments — it also by implication reserves sufficient water to accomplish those purposes. Reserved rights contain features in common with both riparian and prior appropriation rights. Reserved rights, like riparian rights, are grounded in the land (in a legal, not physical, sense) — whoever has rights to the land has rights to its water. In addition, like riparian rights, reserved rights are not lost by nonuse. Reserved rights, however, share two crucial similarities with prior appropriation rights. First, the reserved right has a "priority date" determined by the date that the land was reserved by the federal government. Second, senior rights are satisfied before junior rights.

Who holds reserved rights? There’s no question that the federal government does. Whether Indian tribes do is still not clear. Do tribes retain water rights on their lands because they’ve lived on them since "time immemorial?" If so, their reserved rights would be considered "aboriginal rights," and under prior appropriation law would take precedence over the rights of any other user. Or, do the tribes have reserved water rights only because their present lands are reservation lands, granted to them by the federal government? If this is the case, then their rights are limited by the terms of their treaties, as ratified by Congress, and any other Congressional laws governing Indian rights and activities.

How much water is reserved? The general principle is "as much water as necessary to accomplish the purposes of the reserved lands." The Winters case established the general principle in 1908. The court reasoned that the Fort Belknap reservation lands, set aside so that tribal members might become self-sufficient farmers and ranchers, could hardly fulfill that purpose if it didn't have enough water for irrigation and stockwatering. A later court decision, Arizona v. California, came up with a formula to determine an exact amount of reserved water. Experts would use soil conditions, terrain, hydrology, and other scientific measures to determine the number of "practicably irrigable acres" on a reservation.

For what purposes are water reserved? The question here is whether reserved water can be used for purposes other than those stated or implied when the reservation was originally made. In other words, if the federal government granted a tribe reservation land, and water rights, so that they could become farmers and ranchers, could the tribe later use that water to preserve fish habitat instead of for irrigation? Similarly, can the US Forest Service use its reserved water right to preserve instream flows for recreation or aesthetic purposes? The courts have not offered a definitive answer to these questions.