Mapping of Holocene River Alluvium along the San Pedro River, Aravaipa Creek, and Babocomari River, Southeastern Arizona

The purpose of these investigations is to document and map the extent of Holocene channel and floodplain alluvium associated with the San Pedro River and its major tributaries in southeastern Arizona. Mapping done in this study will be used by Arizona Department of Water Resources (ADWR) staff as part of their effort to delineate subflow zones in the San Pedro River Watershed. The Maricopa County Superior Court has requested that ADWR delineate subflow zones associated with the San Pedro River as part of its work in the Gila River water rights adjudication. Geologic mapping is a primary function of the Arizona Geological Survey (AZGS), so in cooperation with ADWR staff we have established procedures and protocols for documenting and mapping the extent of Holocene floodplain alluvium along rivers in Arizona.