Archaeological Investigations at Los Pozos, AZ AA:12:91 (ASM), for the EW-010A and Regional Reclamation Facility Effluent Pumping Projects, Pima County, Arizona

Summary

Data and interpretations from four archaeological projects at the City of Tucson (COT) Reclaimed Water Treatment Plant are presented in this volume. The work areas lie entirely within the prehistoric site of Los Pozos, AZ AA:12:91 (ASM). The work was conducted by Desert Archaeology, Inc., in advance of projects by Tucson Water: the drilling of well EW-010A (EW10) (COT Project No. 13-01) and the Regional Reclamation Facility Effluent Pumping project (RRFEP) (COT Project No. 13-08). Monitoring work of construction activities related to the latter project form a third project (COT Project No. 1308), and the installation of a reclaimed waterline connected to EW10 forms the fourth (COT Project No. 15-05).

The project areas are located in the northern Tucson Basin on the east bank of the Santa Cruz River. The presence of the river along a relatively wide floodplain with fertile deposits made this location desirable for prehistoric subsistence pursuits, including cultivation, as attested to by prehistoric material remains, the presence of maize, and preserved habitation and other features from Middle Archaic times through the Hohokam late Classic period (A.D. 11501450). The bulk of the work, to date, has revealed cultural resources dating to the Cienega phases (800 B.C.-A.D. 50) of the Early Agricultural period (2100 B.C.-A.D. 50). Increasing evidence of earlier occupations, however, is coming to light, and more instances of surviving Hohokam-aged manifestations are being discovered. The current projects contribute to our understanding of the early occupations.

Based on radiocarbon dates, features in the project area date to the recently named Silverbell interval (2100 1200 B.C.), indicating that substantial occupation of the Los Pozos floodplain west of the geomorphic portion and the Holocene terrace occurred during pre-San Pedro phase times. In all, 245 prehistoric features were identified, including pit structures, possible ramadas, extramural pits, and mortuary contexts.

The research presented here benefitted greatly from previous work at Los Pozos and at the adjacent Wetlands site, AZ AA:12:90 (ASM), by Desert Archaeology and others. Combined data suggest the Wetlands-Los Pozos prehistoric community was closely tied to a particular landscape, which was dominated by a massive overflow paleochannel of the Santa Cruz. This channel, with its complex history and many other smaller but substantial overflow channels, created a landscape of at least seasonally predictable water for maize cultivation and other needed resources, such as game and wood, closer to home than even the river's main channel. The specific natural landscape of undulating surfaces in the project areas may have led to maize cultivation in natural, well-watered swales without constructed fields or canals.

A later Hohokam-aged canal, AZ AA:12:1139 (ASM), was discovered in the RRFEP project area, and it illustrates that the floodplain remained highly desirable for extended periods of time. A model of the diachronic human response to this environment suggests the anthropogenic landscape created by this prehistoric community shifted across the landform according to changing environmental regimes while remaining committed to the overall area.

This Resource is Part of the Following Collections

• Desert Archaeology DAHA Resources   •
• Digital Archive of Huhugam Archaeology (DAHA)

Keywords

Spatial Coverage

Individual & Institutional Roles

Contact(s): Desert Archaeology, Inc.

Contributor(s): Jenny L. Adams; Michael W. Diehl; James M. Heidke; John A. McClelland; Fred L. Nials; R. Jane Sliva; Christine H. Virden-Lange; Jennifer A. Waters; Gregory J. Whitney; Helga Wocherl

Prepared By(s): Desert Archaeology, Inc.

Submitted To(s): City of Tucson Historic Preservation Office

Record Identifiers

Accession No. (s): 2010-108

Arizona Antiquities Project Specific Permit No.(s): 2010-080ps

City of Tucson Project No.(s): 15-05; 13-01; 13-08

Burial Agreement Case No.(s): 2010-012

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