Probabilistic Decision Support: Precision utilizes the Ensemble Stream Flow (ESP) forecasts that are produced by the California Nevada River Forecast Center (CNRFC) to propagate uncertainty through the RiverWare Operations and Accounting model and quantify the uncertainty in reservoir operations which facilitates risk based decision making. These probabilistic forecasts are presented to basin stakeholder and decision makers on a monthly basin to support their seasonal operational decisions. Additional probabilistic forecasts are produced to support high stakes decisions including but not limited to: determining releases to fill reservoirs, assess the risks of planned maintenance and construction, and support operational decisions mandated by legal policy.

Accounting: TROA allows for many complex transactions to occur, requires a precise daily accounting of the system, and requires monthly coordination of reservoir operations to best meet the goals of the major parties in the basin. A daily timestep RiverWare operations and accounting model was developed by the TROA Planning Office in coordination with Precision Water Resources Engineering and the Bureau of Reclamation Lahontan Basin Area Office to facilitate implementation of this agreement. Modeling support is provided to the United States Water Master’s office who complete a daily accounting of reservoir releases and storages that is made available to basin stakeholders multiple times per week.