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Why is this study important?
It represents the most recent published groundwater-flow model analysis specifically for the Little Chino Sub-basin.
Timmons, Daniel, and Springer, Abe, 2006, Prescott AMA model update report: Arizona Department of Water Resources, 77 p. In 1995, the Arizona Department of Water Resources developed a regional groundwater-flow model to quantify the impacts of various management programs on groundwater resources of the Prescott Active Management Area (Prescott AMA). New geologic data as well as new data on aquifer properties, water levels, pumpage, groundwater discharge, and groundwater recharge have continued to be gathered since then; the model was updated in 2002 to simulate groundwater conditions from 1940 to 1999 as well as to predict future groundwater conditions from for the years 1999-2005. The model was updated again in 2006 (this report) to take advantage of additional, more recent data. The model continues as an important tool for assessing the impacts of water use and water management in the Prescott AMA. The model results indicate that the groundwater resources of the Prescott AMA continue to be depleted on a regional basis. This has resulted in decreased groundwater storage in the aquifers of the area. In addition, natural groundwater discharge from the Prescott AMA has decreased with potential impacts on riparian areas and downstream users. Over the period from 1940 to 2004, groundwater discharge from the Little Chino sub-basin (as groundwater discharge at Del Rio Springs and subsurface flow out of the model area) has declined from around 7,600 acre-feet/year to around 2,700 acre-feet per year, a decline of 4,900 acre-feet/year. Discharge from the Upper Agua Fria sub-basin as base flow in the Agua Fria River declined approximately 700 acre-feet/year over the same time period. Over the period from 1939-2004, simulated groundwater storage in the Upper Alluvial Unit aquifer and Lower Volcanic Unit aquifer has declined by approximately 500,000 acre-feet. CLICK HERE TO READ THE FULL REPORT
