The Application of Light Detection and Ranging (LiDar) Technology to Improve the Management and Protection of Heritage Assets in the American Falls Archaeological District, Idaho
Data obtained through LiDAR technology will provide a far greater quality of information for the cost of erosional factors affecting noncollectible heritage assets in the American Falls Archaeological District (listed in the National Register of Historic Places) than can be accomplished through traditional methods.
This superior data will aid in a better understanding of the natural forces and human activities that speed the erosion of archaeological sites in the district and provide for more well-informed management decisions to manage and preserve these invaluable cultural resources under the Bureau of Reclamation's (Reclamation) control and jurisdiction, a responsibility required both by national law and Reclamation policy.
Need and Benefit
There exists a great need in Reclamation to provide better protection of the heritage assets under its control and jurisdiction as directed by several legislative authorities. Heritage assets are irreplaceable prehistoric and historic-era properties, including many dams, structures, buildings, and other facilities built by Reclamation, but also archeological sites and historic properties existing on Reclamation lands.
Protection of heritage assets is accomplished through periodic condition assessment of the asset itself. Currently, site condition assessment methods are subjective written descriptions of environmental and cultural features accompanied by a map of selected items or points. However, maps are time consuming and labor intensive. Photographs may be taken to help provide visual documentation of condition, but archeological features tend to show up poorly, if at all. On the whole, this level of site condition assessment documentation is extremely poor when applied over time; individual archeologists will invariably interpret site condition factors differently from one another, negating the entire condition assessment process because of the inescapable subjectivity that results from a lack of hard, quantifiable data.
A very important Reclamation-owned archeological area is in immediate danger from several erosional factors. This area lies within the American Falls Archaeological District, a bounded area that is listed in the National Register of Historic Places. The district contains 158 contributing archeological sites--131 on Reclamation land, 27 on Bureau of Land Management (BLM) land--and represents almost continuous human occupation spanning more than 9,000 years. From Paleoindians to modern Indians to pioneers on the Oregon Trail, people have found this area just north of the Snake River to be one of value in terms of natural resources, spirituality, and beauty. All of these factors, including its surface and buried cultural resources, are now threatened by wind and water erosion, Off-Road Vehicle (ORV) use, and cattle trampling. Interagency cooperation between Reclamation and BLM on this project could help resolve these mutual issues.
New technologies exist outside Reclamation that, if applied accurately and at regular intervals, could provide an extremely high quality and quantity of quantifiable data. These data could then be analyzed and compared to a baseline of data to detect changes over time, greatly reducing subjectivity and furnishing management with information that would promote better decisionmaking processes.
LiDAR technology is an ideal data collection tool for an archeological site condition assessment study. Current LiDAR technology is capable of recording elevational and topographical measurements that have a vertical precision of 15 centimeters (a relative accuracy of 4-6 inches). This level of accuracy would allow for recording most erosional factors, including ORV trails, dune heights, and even footprints. The collection of these data in the same area over a span of 3 years would allow for change detection in elevations, allowing for an understanding of erosional patterns and rates that could then be used to assist management with decisions that could alleviate--or possibly eliminate--the existing causes of deterioration.
According to our background research, using LiDAR to ascertain archeological site conditions has not been attempted--either within or outside the U.S. Department of the Interior. This study would represent a revolutionary step in cultural resources management and could be an enormous boon for Reclamation in both its fiscal and legal responsibilities to heritage preservation that would likely garner national attention.
Bureau of Reclamation Review
The following documents were reviewed by experts in fields relating to this project's study and findings. The results were determined to be achieved using valid means.
Change Detection Methodology for the Application of Light Detection and Ranging (LiDAR) Technology to Improve the Management and Protection of Heritage Assets in the American Falls Archaeological District, Idaho (final, PDF,
By Mr. Dale R. Lindeman
Report completed on September 26, 2012