Why would anyone want to inhibit the development of instream flow rights in Arizona? The answer is more complex than it may seem.
Instream flow rights serve as the mechanism by which an entity can help preserve water flowing in streams for the “beneficial use” of fish and other wildlife. Arizona has seen a significant uptick in instream flow right applications in recent years, both from government agencies and from environmental groups seeking to reserve as much surface water for species and habitat as possible. Most Arizonans probably recognize the value in protecting our relatively fragile desert ecosystems. Furthermore, newly established instream flow rights automatically become the most junior rights under the prior appropriation system — so, in theory, they should not affect senior right holders.
These benefits notwithstanding, a bill currently moving through the Arizona legislature (SB 1236) seems to take aim at instream flow rights. The bill would require applicants to not only submit 5 years of continuous stream flow data for the reach in question but also to more thoroughly characterize the beneficial use associated with leaving the water in the stream. The cost and technical difficulties of collecting continuous data for 5 years and documenting ecosystem benefits pose a significant hurdle to anyone looking to establish an instream flow right. In fact, this requirement could effectively kill future instream flow right applications, and it would explicitly reject pending applications that don’t meet the new criteria.
The motivation for preventing the growth of instream flow rights appears to stem from the fact that they have become, in practice, more powerful than they appear on paper. Contrary to the deference that these junior rights must theoretically pay to senior rights is the “no-harm” rule for transferring surface water rights. This rule requires the applicant to consider the potential impacts of a proposed transfer on both junior and senior rights alike. Therefore, new instream flow rights establish a standing in the watershed that can be used to oppose the severance and transfer of existing surface water rights — even if those rights are the most senior in the system. In other words, the proliferation of instream flow rights threatens the ability of existing surface water right holders to manage their rights and could potentially effectively “lock” existing rights to their current place and purpose of use indefinitely.
The desire to avoid this threat is understandable; one of the most basic principles in Western water is that senior rights should not have to defer to junior rights. Nonetheless, targeting instream flow applications to protect this doctrine addresses only one symptom of a deeper issue. The real problem is not instream flow rights themselves, but their misuse to effectively freeze all senior rights. Preserving desert ecosystems is important; however, the potential for relative newcomers to effectively reduce the value of more senior water rights is a complex legal problem with far-reaching implications. As such, legislation dealing directly with this root issue should not be expected anytime soon.