Hydrology

Adapting and validating existing water models to the arid West

In order to understand how changing water flows will affect producers and allocation institutions, the first necessary aspect of the project is to develop a water flow model adapted to the specific study area. The project will produce an adaptation of the National Water Model (NWM), a simulation and forecasting model developed by the National Center for Atmospheric Research (NCAR), to simulate hydrologic fluxes and stores across the arid West.

Using the validated hydro-climate model to quantify water supplies and variation at a basin-level

The hydrologic modeling effort expects to produce both a 30 year forecast of water supply in the arid West that can be updated and probability distributions for monthly water availability. These predictions and prior-year calibrated data can be input into existing regional water allocation operations models. Within the recalibrated water model from the first part of the project, we will produce a historical and predictive water supply model at a basin-scale by isolating the different changes is streamflow, reservoir, snowmelt and groundwater.

Integrating climate change scenarios into the model to predict snowpack changes and associated changes in water supply

A set of predicted future climate scenarios from the Coupled Model Intercomparison Project (CMIP) projections will be input into the model to understand how snowpack and other water storage projections change under different potential climate scenarios. This updated model can be used to predict monthly water flow in study area basins under different snowpack scenarios. This information can be used to identify which basins have agricultural producers with the greatest risk of failure to exercise water rights under different changes in climate. Finally, the information collected as part of the regional hydrologic modeling effort will be incorporated into decision-making models

Photo: Bob Wick, BLM