Year of Award


Document Type


Degree Type

Master of Science (MS)

Degree Name

Resource Conservation

Department or School/College

College of Forestry and Conservation

Committee Chair

Martin Nie

Commitee Members

Michelle Bryan, Michael Patterson


Instream flow, Tribes, Reserved Rights, American Indian Water Rights, Tribal Water Rights, Instream Flow Protection


University of Montana

Subject Categories

Indigenous, Indian, and Aboriginal Law | Water Law


Native American Tribes have been fighting for access, legal recognition, and the control over their water rights for more than a century. Today less than ten percent of the 566 federally recognized Tribes have had their rights legally defined and secured under the law. One particularly complicated and compelling aspect of tribal reserved water rights involves the protection of water instream. Since the McCarran Amendment and state court quantification of Winters reserved rights, Tribes have sought to quantify and protect reserved water rights through negotiated settlement agreements. Although the settlements seek to bring certainty, resolution, and final integration of reserved water rights into contemporary western water law, the results for instream flow protection are far from clear.

This thesis examined the legal provisions that quantify, describe, and limit tribal reserved water rights within the 30 federally recognized tribal reserved water rights settlements to assess the extent of tribal authority to protect instream flows. Five broad themes and issues emerged from an analysis of the settlements: (1), most of the settlements have not asserted aboriginal instream flow rights nor defined instream flows, (2) there are significant restrictions imposed on Tribal authority to change Winters reserved rights water rights to non-consumptive uses, (3) there are direct and indirect limitations on tribal authority to enforce instream flow protections in many of the settlements, (4) opportunities to market or lease water for non-consumptive uses off-reservation are severely constrained and largely undeveloped, and (5) the majority of the settlements do not fully clarify jurisdictional responsibilities needed to protect instream flows.

The extractive and utilitarian legacy of the prior appropriation system has resulted in the de facto prioritization of consumptive uses in western state water law. This context has carried over to influence tribal reserved water rights settlements and will frustrate the extent many tribes will be able to protect non-consumptive uses of water. Settlements that broadly define the tribe’s use of their quantified water right, reserve explicit authority to protect instream flows, address groundwater regulation, and clarify jurisdictional responsibilities between the tribe and the state stand to avoid future ambiguity and conflict over instream flow protection. Future settlements should not only recognize tribal authority to utilize reserved rights for protecting instream flows of water, but also more broadly reflect the governmental role that tribal nations are due as sovereign water managers.



© Copyright 2015 Dylan M. DesRosier