West Virginia University

Selected Student Highlight

Interpreting Site Formation Processes Affecting Re-emergent Cultural Sites within Reservoirs: A Case Study of St. Thomas, Nevada.
Denyse Wyskup

Aerial photo taken June 2003. Re-emergent beach ridges appear as crenulations in the foreshore and note re-emerging structure. Photo source: Lake Mead NRA.

The inundation of cultural resources due to the construction of dams as water retention mechanism is a global problem, affecting thousands of historic and prehistoric sites.  Recent warming trends, in combination with increasing water usage from growing populations and urban expansion has initiated dramatic pool-level shallowing in many reservoirs, especially in the American Southwest, resulting in the re-emergence of inundated cultural sites.  The “ghost town” of St. Thomas, Nevada, represents one example of a site that was impacted in this manner.  This historic settlement is one of many hundreds of sites that became submerged when Boulder Dam was constructed to impound the waters of the Colorado River to create Lake Mead reservoir in 1935. 
      My research identifies those processes governing and manipulating site formation and the stability of remaining structural features.  Field investigation, soil analysis, X-ray diffraction, examination of historic gauge records and aerial imagery indicates that St. Thomas, and perhaps other cultural sites located within the down-draw boundary of reservoirs, are susceptible to severe degradation from mechanical lacustrine wind-wave action, biologic intrusion and structural instability caused by shrink-swell sediments.  Preservation and conservation measures for cultural sites located within these environments are not well developed; the data collected and the results generated from this research are valuable tools in formulating and constructing conservation plans for these sites.