Diversion Dam Cave (10-AA-99): A Paleoindian Site near Boise, Idaho

Abstract

In this article we describe the results of excavation at the Diversion Dam Cave (10-AA-99) near Boise, Idaho, sponsored by the Bureau of Reclamation. Although the site has been heavily impacted over the years by illegal digging and urban encroachment, the data from these excavations confirmed that some deposits are intact. Radiocarbon data suggest a Paleoindian occupation, prior to 9220 ± 100 RCYBP and as far back as approximately 12,000 RCYBP. No artifacts diagnostic of a specific cultural group were recovered, but the hearth features, hand polish on rocks, and river cobbles with pecking damage all point to human occupation. Faunal analysis suggests that small and medium mammals and fish were exploited, while botanical data suggest the use of both local and more distant resources as fuel. Although the cultural deposits were sparse, radiocarbon dates suggest occupation during the Paleoarchaic Period, a time frame with few examples in Idaho.