The Arizona Dept. of Water Resources has released a 1,300 page report on subflow zones along the San Pedro River as part of a legal adjudication of water rights. Subflow is that part of the river that flows in the subsurface. Delineation of the subflow will determine who has rights to groundwater. The court defined subflow as occurring in the Holocene floodplain alluvium.
The AZGS did the geologic mapping of Holocene-aged units along the river and tributary valleys for the ADWR study. Those 1:24,000-scale maps will probably be released publicly next week.
The Camp Verde Bugle did as nice review as I've read of the issues on the San Pedro as a possible prelude to simlar adjudication battles on the Verde River.