SNAPP - Sharing Water -- Evaluating Environmental Water Transaction Programs

Water acquisition programs support instream flows and other environmental water needs in many areas of the western United States. They have evolved over several decades, expanding from relatively simple two-party transactions involving modest water volumes to complex, multi-sector deals that move substantial volumes of water back to nature. Such programs now represent an important water management tool and impetus for collaboration among stakeholders, yet most evaluations of these programs' outcomes and effectiveness have focused exclusively on environmental metrics, without adequate attention to impacts on other water users or local economies. Given the importance of accomodating environmental water needs more fully in water resource plans, and the need to expend program resources carefully, a systematic, multi-objective evaluation framework is needed. This paper fills that need by articulating a suite of relevant environmental and socio-economic indicators for evaluating environmental transaction programs and portfolios. We have applied these indicators to environmental water transaction programs located in the western United States of Oregon, Montana and Nevada. The application to local programs illustrates both the challenges and the value of applying a systematic evaluation framework. More importantly, it quanitifies tradeoffs between sectors and helps identify opportunities for creative water transactions that benefit multiple sectors and the environment. The indicators are useful both in evaluating transactions already completed and in strategic planning and prioritizing for future transactions. A detailed guidebook to assist parties in applying this evaluation framework is available online.