Sensitivity analysis and inverse modeling of an updated and refined numerical groundwater flow model of the Prescott Active Management Area, Yavapai County, Arizona

Abstract

The Prescott Active Management Area (AMA) represents two subbasins that contribute groundwater toward the headwater springs of the Verde River; the Little Chino and the Upper Agua Fria. The Verde River, located in Northern Arizona, represents one of the only remaining perennial rivers in the state. The Arizona Department of Water Resources constructed a numerical groundwater flow model of the Prescott AMA, (Corkhill and Mason, 1995) and updates to the model (Nelson, 2002). This study includes grid refinement and hydrologic parameter updates on the Prescott AMA model. Then, a sensitivity analysis and inverse simulations were conducted on the newly refined model. Results indicate the importance of the newly added data, and show that while the refined and updated area has high sensitivity to the matching of observed values, the most important area to focus for future data collection is near the center of the model domain.