Phase I Archaeological Survey for the Proposed Bridge Replacement on SR 25 at the Savannah River, Chatham County, Georgia

Edwards-Pitman Environmental, Inc. (EPEI), has conducted a Phase I archaeological survey for the proposed bridge replacement on State Route (SR) 25 at the Savannah River in Chatham County, Georgia (GDOT PI No. 0013741, HP No. 81019-001). This survey was conducted for the Georgia Department of Transportation (GDOT) under a contract with Heath & Lineback Engineers, Incorporated (HNL). The GDOT proposes demolishing and replacing bridge number 051-0054-0, known locally as the Houlihan Bridge, with a proposed alignment that would be offset 15.2 meters (m) (50 feet [ft]) north of and parallel to the existing alignment. The proposed bridge would be a fixed span that would provide the required horizontal and vertical clearance to meet navigational needs. The bridge would be lengthened to reduce impacts to right-of-way (ROW) and environmentally sensitive areas. The proposed project would replace the bridge without widening the SR 25 roadway.

There were no design plans at the time of survey, thus the survey area for the proposed project includes all areas within an Environmental Survey Boundary (ESB) provided to EPEI by HNL. The ESB measures approximately 1.5 kilometers (km) (0.9 mile [mi]) in length and between 132 and 181 m (433 and 594 ft) in width, and is designed specifically to encompass all areas of possible/ foreseeable ground disturbance as a result of the proposed project. When design is complete, the project’s area of potential effect (APE) will likely be smaller than the ESB that is shown.

To the west of the Savannah River, the project traverses private and state-managed properties; to the east of the Savannah River, the project is located on Federal Lands administered by the United States Fish and Wildlife Service (USFWS) on Onslow Island within the Savannah National Wildlife Refuge (SNWR). As such, a Permit for Archaeological Investigations was obtained under the Archaeological Resources Protection Act (ARPA) (Permit No. SAVWR072718). A Special Permit for Research and Monitoring was also obtained from the SNWR (Permit No. 2018-29).

Prior to the archaeological survey, background research was conducted that included a review of historic maps and aerial photographs at the University of Georgia (UGA) Map Library, the Georgia Archaeological Site File (GASF), and Georgia’s Natural, Archaeological, and Historic Resources Geographic Information System (GNAHRGIS) database. The review found that 19 previously recorded archaeological sites are located within this radius while five surveys have previously been conducted within or adjoining the ESB. Although an additional water survey conducted within the Middle River identified many of the resources located within the 1-km (0.62-mi) radius of the ESB, the survey was not within or adjoining the current ESB.

The objective of the archaeological survey was to locate archaeological resources potentially affected by the project and to evaluate them in accordance with Section 106 of the National Historic Preservation Act (NHPA). Fieldwork for the Phase I survey was conducted by EPEI on October 30 and 31, 2018. This work resulted in the identification of two new archaeological sites (9CH1514 [Loci A, B, and C] and 9CH1517) and one district.

Site 9CH1514 has been divided into loci due to the placement of affiliated structural remains in discontiguous locations. Site 9CH1514 (Loci A and B) represent the remains of the original bridge over the Savannah River, which was constructed in the location of SR 25 during the 1920s. A comparative analysis of the timbers that comprise site 9CH1514 (Locus C) suggests that they represent the twentieth century use of the shoreline following the 1920s bridge construction. The removal of the original bridge structure during the reconstruction of the road and bridges during the 1930s and 1940s, as well as the installation and modern renovations of the Houlihan Landing, would severely impact the potential of the pilings and timbers at 9CH1514 to contain substantive archaeological information. As such, EPEI recommends site 9CH1514 as ineligible for inclusion on the National Register of Historic Places (NRHP) under Criterion D. No further archaeological work is recommended at this site.

Site 9CH1517 represents a portion of the reinforcement structures installed during the pre-1825 construction of the Potter Open Canal or its later maintenance and is within the Colerain Plantation District, which is described below. The puncheons, planks, and timbers at 9CH1517 lack both integrity and the potential to contain significant data on their own, and thus the site is recommended as ineligible for individual listing on the NRHP under Criterion D. The reinforcement structures at the site form part of the Potter Open Canal, however, which was constructed during the Plantation era to serve as both transportation and irrigation to the surrounding rice fields, and was integral to the cultivation and transportation of rice, a significant context within Chatham County and the Barrier Islands of Georgia. Based upon this association, and the fact that the canal as a whole maintains multiple aspects of integrity related to its function in the cultivation of rice, the Potter Open Canal, and the portion of it recorded as 9CH1517, is a contributing resource to the Colerain Plantation District, which is recommended as eligible for the NRHP (see below). It is recommended that 9CH1517 be protected by the establishment of an Environmentally Sensitive Area (ESA) marked with orange barrier fencing (OBF) in order to prevent inadvertent impacts from the proposed project.

The Colerain Plantation District was part of an important rice-growing enterprise begun by 1760 that lasted until the 1890s. It is recommended as eligible for inclusion on the NRHP under Criterion A in the areas of agriculture, ethnic heritage, and social history for its extant collection of tidal rice fields. The district is also recommended as eligible under Criterion C in the area of landscape architecture as the landscape within the district retains many of its historic features and much of its historic integrity as related to rice production, and because evidence of this type of rice production is somewhat limited in Georgia. The district is also recommended as eligible for the NRHP under Criterion D for its ability to yield important information regarding the construction, spatial arrangement, and associated factors related to the production of rice in Chatham County and the Barrier Islands of Georgia. It is recommended that the Colerain Plantation District be protected by the establishment of an ESA marked with OBF in order to prevent inadvertent impacts from the proposed project.