Pueblo Reservoir Excess Capacity Storage Account NEPA Environmental Assessment (EA) Analysis (2016-2018)

Precision used the Arkansas Basin RiverWare® model to evaluate the hydrologic impacts of Reclamation's Pueblo Reservoir Temporary Excess Capacity (EC) Storage Account program as part of the 2018 Final Programmatic Environmental Assessment (EA) for Pueblo Reservoir Temporary Excess Capacity Storage Contracting Program. Leveraging the model's explicit simulation of all of the >40 distinct EC storage accounts — including projected inflows, outflows, and storages — the analysis evaluated the potential direct and indirect impacts of the accounts on the hydrology throughout the basin. The analysis used 4 time periods (2017, 2032, 2047, and 2058) that represented the expected increased utilization of EC accounts by many entities into the future. The analysis was vital in supporting Reclamation's Finding of No Significant Impact (FONSI) for the storage accounting program, which provides many basin entities with much needed and advantageous storage options for various water rights and other yield sources.