The Challenge

Recent decades have witnessed significant changes in snowpack volume and in the timing of snowmelt across the western United States. These changes, which are expected to intensify due to climate change, have impacted seasonal water availability for agricultural producers and have put stress on water allocation institutions.

What We Are Doing

We are an interdisciplinary team of researchers working to understand how predicted changes in mountain snowpack will alter the quantity and timing of water flows, how agricultural producers and other downstream users will respond to changes in water flows, and how water allocation institutions can be amended to help communities adapt.

Expected Outcome

The goal of the SNOWPACS project is to support the adaptation of agricultural communities in the western United States to shifts in the timing and quantities of snowmelt-derived water supplies. To accomplish this goal, we have assembled an interdisciplinary team of researchers from six institutions who are working together to understand the complex relationships between changes in mountain snowpack, downstream water availability, water allocation institutions, and agricultural production.

This project will provide information and tools to water managers, agriculture producers, and other decision-makers to improve the efficiency of water allocation institutions and support continued agricultural production in snowmelt-fed basins in the western United States.

Project Components

The SNOWPACS project has five components:

  • Hydrology
    • Refine predictions for how changes in mountain snowpack impact seasonal water availability in snowmelt-fed basins.
  • Agricultural Production
    • Statistically model how agricultural producers' cultivation decisions change in response to changes in seasonal water availability.
  • Water Allocation Institutions
    • Analyze how water allocation institutions are likely to adapt to the stress caused by changing seasonal water availability.
  • Integrated Hydro-Economic Modeling
    • Integrate hydrologic and economic model(s) to analyze how changes in seasonal water availability impact water deliveries under current allocation institutions and how these institutions can be enhanced to mitigate costs to agriculture.
  • Collaborative Research Framework
    • Design and implement a collaborative research framework that integrates all research components and supports knowledge co-production through Technical Advisory Group(s) comprised of local water managers who represent diverse water uses.

Frequently Asked Questions

What are the water allocation institutions in the arid West?

Institutions are essentially the "rules" of water allocation. In the arid West, these include such legally-defined systems as prior appropriation doctrine, beneficial use, proportional sharing schemes, private ownership and markets, and modifications to rules that have occurred over time. Prior appropriation (PA) and beneficial use are perhaps the most important factors to consider in the region. Under PA, the first person to divert water for a beneficial purpose acquired a "priority date" at that time to use that specific amount of water for the specific beneficial use indefinitely in the future. Successive claims receive a specific amount and use, with the water delivered by priority date.

Prior appropriation is the predominant institution in all Great Basin states. It facilitated development of irrigated agriculture by a process of permitting changes in place of use (POU) and purpose of use. Landowners can apply for a change in POU while keeping their original quantity and priority of water to irrigate different locations of their land. Water rights can be transferred from irrigation to municipal uses, but transfers are permanent, meaning these rights cannot be transferred back to agriculture.

What do we know about water flows in the arid West?

Mountain snowpack provides a source of water that augments the most significant stocks of water in the region, groundwater and reservoirs, with a regulated water flow over time. Climate changes have recently caused the timing of that flow from mountain snowpack to occur earlier in the season. The degree of these changes in timing means that senior water rights holders (which are more commonly agricultural producers) actually get less water than junior water rights holders (more commonly non-agriculture or municipalities). Currently, the National Water Model (NWM) estimates flows in the arid West. This project will adapt the NWM to the arid West in collaboration with the National Center for Atmospheric Research (NCAR) in order to be better able to predict future flow changes under different climate projections.

How does this issue affect people?

Changing timing of peak water flows creates the potential for winners and losers in water systems. Under the current water allocation institutions in much of the arid West, those with higher priority rights may benefit from earlier peak flows, while newer rights holders may not get to exercise their rights. While the existing institutions offer the ability for rights to be exchanged and water uses to change under certain circumstances, this still can potentially lead to permanent loss of agricultural lands, lower agricultural yields, and higher water costs in municipalities.

Why are economists leading this project?

This project utilizes economic theory and analysis as a lens for understanding the decision makers involved in water allocation. By understanding how water rights holders and managers act to maximize private or social benefit, we can better understand the efficiency or inefficiencies of the current institutions and how alternatives may lead to better overall outcomes. Climate change is leading to more uncertain conditions for water rights holders and managers, which has necessitated improved forecasting and modeling to aid in decision making. In order to address these gaps, economic analysis can build from a foundation of improved hydrologic modeling and greater understanding of the barriers faced by stakeholders and policymakers in taking steps towards adaptation to these new conditions.

Where can I learn more about water law in my state?

 
News Articles, Fact Sheets, Reports...
Water Sustainability and Climate in the Truckee-Carson River System, Western United States: 10 Key Takeaways from the Water for the Seasons Collaborative Research Program.
This Special Publication briefly introduces the Truckee-Carson River System case study area, describes the Water for the Seasons research program, and presents 10 key takeaways from this five-year collaboration between local water managers and researchers.
Sterle, K., Singletary, L., Lee, G.-E., Rollins, K., Pohll, G., McCarthy, M., Rajagopal, S., Albano, C., Boyer, W., Huntington, J., Dettinger, M., Niswonger, R., Morway, R., Kitlasten, W., Gardner, M., Coors, S., and Jose, L. 2020, Extension I University of Nevada, Reno, SP-20-02.

Learn more about the program's team