The site is located within the West Salt River Valley sub-basin of the Phoenix Active Management Area. The Salt River Valley is an alluvial filled basin located in the basin and range physiographic province. The site is underlain by primarily sandy silts and silty sands, with interbedded clay layers and gravelly sand zones.

Due principally to the lining of the SRP Grand Canal to the north of the site and the ongoing drought, depth to groundwater has declined considerably in the past several years. In 1997, the depth to groundwater was approximately 105 feet below ground surface (bgs), and by 2002 it was approximately 123 feet bgs. Depth to groundwater as of March 2004 was 130 feet to 139 feet bgs.  Depths to groundwater currently range from approximately 133 feet to 158 feet bgs. Groundwater flow is to the south-southwest beneath the site.