Indigenous Rights and Climate Change: The Influence of Climate Change on the Quantification of Reserved Instream Water Rights for American Indian Tribes

Abstract

The people indigenous to the Western portion of the lands now referred to as North America have relied on aquatic species for physical, cultural, and spiritual sustenance for millenia. Such indigenous peoples, referred to in the American legal system as Indian tribes, are entitled to water rights for fish habitat pursuant to the Winters Doctrine, which holds that the federal government impliedly reserved water rights for tribes when reservations were created. Recently, the methodology for quantifying these rights has been the Instream Flow Incremental Methodology (IFIM) and/or one of its major components, the Physical Habitat Simulation Model (PHABSIM). These models result in water right claims for fixed quantities of water, which—although not required by law—result in instream water rights that are decreed without any means for adjustment to account for changing conditions. Ultimately, climate change will likely alter the amount of water necessary to protect aquatic habitat, rendering obsolete any water right that is based on a fixed quantity. As climate change continues to worsen, we argue that quantifying reserved water rights for inflexible fixed quantities imposes an unreasonable burden on American Indian tribes. Instead, we suggest the application of a number of integrated technical and legal solutions to mitigate the uncertainty Indian tribes currently face from climate change as they seek to protect their rights, resources, and homelands.