Wet-Site Excavation at Sunken Village Site on the Columbia River

The extensive in situ acorn pits are the most remarkable fea­tures at this landmark site. During surface exposure and mapping, all such pits contained remnants of whole acorns. Also wood and fiber artifacts were observed in and around these pits, including a shredded cedar bark cape/skirt fragment, a broken wooden wedge, wooden arrow shafts, and a well-preserved basket distinctive of the region's fine basket work. The basket piece was found with intact base and sides (no rim remained) all carefully cross-warp twined of split cedar root (identified by Bud Lane, master weaver, Siletz, and Patricia Gold, master Wasco weaver, Warm Springs; Figures 5 and 6). The style of this basket is definitely from this region and demonstrates an ancient continuity of this style of basketry. Baskets found from northern ancient wet sites are of a very different style, and themselves demonstrate at least 3,000 years of basketry cultural continuity in Salish, Makah, and Tsimshian traditional territories. For full final report on two summer's of explorations, second one sponsored by Japanese Archaeology program, see: Croes, Dale R., John L. Fagan and Maureen Newman Zehendner 2009 Sunken Village, Sauvie Island, Oregon, USA, A Report on the 2006-2007 Investigations of National Historic Landmark Site 35MU4. Journal of Wetland Archaeology Special Edition 9, 1-216. Available on Amazo

The Physical and Cultural Background

The Sunken Village wet site (35MU4) is on one of the most important river junctures on the Northwest Coast of North America – where the Columbia River drainage of British Columbia, Canada and Washington State, U.S.A. is joined by the Willamette River flowing through much of western Oregon State, U.S.A. (Figure 2.1). The site is on Sauvie Island, where a major aquifer pumps under the natural levee into Multnomah Channel, providing a unique 125 m wide beach area where acorns placed in shallow hemlock bough-lined pits were leached in huge numbers by ancient Multnomah Peoples (Figure 2.2)

Ecofacts – Plant and Animal Analyses

Wet sites, due to reduced oxygen, provide excellent preservation of both plant and animal remains. Due to the clear importance of Sunken Village as an acorn leaching and processing location – largely because of the aquifer streaming through this approximately 100–125 m of intertidal beach – the focus in Section 4 is on the leaching pits and acorn remains. First we begin with a look at identifying the actual plant materials and fuels used at this site, requiring both visual observations of the plant remains and also cellular analysis of the wood, fibers and charcoal. Many of the perishable artifacts are introduced in this section while identifying their wood and fiber construction materials. Second we report the abundant acorns and acorn leaching pit features, so numerous at Sunken Village. Third, seed retrieval is explored, comparing the results of flotation techniques and fine wet screening. And finally, the faunal analysis reflects the use of these animal resources in a secondary position, and probably to support the group while managing the acorn leaching pits from this site. The obvious contrast here to other Northwest Coast and Columbia River sites is the reduced focus on fisheries from this location

The 2006 and 2007 Field Seasons at Sunken Village

As mentioned, the 2005 erosion of the dike placed on the natural levee facing the intertidal waterlogged portion of the Sunken Village site had threatened the residents of the island, initiating a proposal by the Sauvie Island Drainage Improvement Company (SIDIC) to place protective rip-rap rock along the face of the bank. Since the site is on navigational waters under the authority of the U.S. Army Corps of Engineers, field evaluation of this National Historic Landmark archaeological wet site was required to assess the potential effects of placing protective rip rap rock on the channel bank in order to comply with U.S. Section 106 of the National Historic Preservation Act (Croes et al. 2006)

Artifact Analyses

Over 50 years of collecting and intentional vandalism at the Sunken Village wet site has demonstrated the potential material culture data preservation at this waterlogged site, and finally we can report a systematic characterization of the overall material culture – both debitage and examples of discrete artifacts. The previously and unprofessionally collected basketry, cordage and wooden artifacts reflected the wealth of wood and fiber artifacts thanks to the waterlogged preservation of the site, however collecting is very selective. The analytical power of the basketry was noted over twenty years ago, reflecting a distinct Chinookan style (Croes 1987). As reported next, this artifact analysis may even have a much broader implications for a North Pacific cultural sharing, both in the use of acorn pit processing and distinct basketry styles, factors never perceived before these initial professional explorations

A Field Report from the Sunken Village Wet Site (35MU4)

During low waters of September a wet site team, sponsored by an international grant from Japan, returned to further record the National Heritage Landmark wet site of Sunken Village (35MU4), Sauvie Island, Portland, Oregon (Figure 1). The one week project (September 16 through 22, 2007) was designed to accurately map the surface features ( especially over a hundred in situ acorn leaching pits and wooden stakes) and surface arti­facts (especially lithic debitage and fauna! remains) as revealed in the limited evaluation of I 060 linear feet (320 metres) of beach before the riprap repair was permitted by the U.S. Corps of Engineers in October of 2006 (Croes, Fagan and Zehendner 2007; a PDF copy of this 2006 field work is available on the web - see References below). The project continues to be co-man­aged through the direct in-put by Cultural Resources Protection Specialists Eirik Thorsgard, Confederated Tribes of the Grand Ronde, and Robert Kentta, Confederated Tribes of Siletz Indi­ans and in consultation with the Confederated Tribes of Warms Springs. A joint team provided the expertise needed to carefully map and record the Sunken Village National Historic Landmark site, consisting of(a) the SPSCC Wet Site Archaeological Inves­tigations and Laboratory team, lead by Dr. Dale Croes, and the SPSCC Computer Aided Drafting Department, lead by Professor Michael Martin, (b) the AINW geoarchaeological and laboratory team, lead by Dr. Michele Punke and Maureen Zehendner, and ( c) the internationally known Wetland Archaeological Team from the National Institute for Cultural Heritage, Nara, Japan, lead by Dr. Akira Matsui. This project was conducted through the sponsorship of a Japanese international grant under the administration of Dr. Akira Matsui, Chief Archaeologist, National Institute for Cultural Heritage, Nara, Japan, as well as support through the SPSCC Anthropology Club, an SPSCC Exceptional Faculty grant, Jean and Ray Auel, and volunteers from Portland State University and the Oregon Archaeological Society. Dr. Matsui brought four Japanese associates to participate in the field work: Dr. Naoto Yamamoto, Dr. Toru Miyao, Dr. Atsushi Iwasaki, and Dr. Tomonori Kanno (Figure 2)