Restoring natural resource access lost during colonization has become an important component of formalizing sovereignty and providing economic opportunity for Indigenous groups. This paper uses satellite data on land use to study the effect of property right settlements for surface water on reservations in the western United States between 1974 and 2012 with robust difference-in-difference methods. We find statistically significant increases in agricultural land use and no change in developed land use. Despite this, back-of-the-envelope calculations reveal that most tribes are using a small fraction of their entitlements, potentially forgoing as much as $1.6 billion in annual production or leasing revenue. We provide evidence that this underutilization may be driven by the inability to construct the necessary infrastructure. Our findings indicate that restoring formal property rights to a single resource is unlikely to provide significant economic benefits unless existing institutional constraints and barriers to development are also addressed.