Laser scanners are able to collect data on the as-is conditions of a historic site to help preservers protect the location or building, gain insight into the existing conditions of the site or understand how it might have looked in the past. Laser scanners are valuable tools for the conservation of historic sites, and there are many locations, structures and buildings that are in desperate need of help.

Preservation Virginia, a nonprofit group whose mission is to safeguard Virginia's historic sites, recently came out with its 2014 list of most endangered sites in the state. The group didn't rank the locations in a particular order, as each of the 11 historic sites are in need of saving. Many of the locations on the list are buildings of significance from the time of the founding fathers or earlier. There are also sites from the Civil War, such as two battlefields, and historically important pieces of infrastructure. 3D laser scanning can aid in the preservation of most of these locations, structures and buildings.

Many historic sites are in desperate need of help
The group's list outlines the exact threats to each of the historic sites on the list as well as the organization's recommended solutions. Many of these solutions involve how to plan around the sites and creating sustainable maintenance strategies through real-world data.

The Bristoe Station Battlefield and the Williamsburg Battlefield are two of the sites in particular that can benefit from the use of laser scanning technology. 3D laser scanners are often used in land surveying to gather topographical data. According to the Update to Civil War Sites Advisory Commission Report, there are more than 1 million acres of battlefields in the state, but only 13 percent were safeguarded in 2009. The Battle of Williamsburg site was found to only have 3 percent of its acres safeguarded. However, Preservation Virginia noted more than 2,000 acres of the Williamsburg site have disappeared since the 1990s, despite the update finding more than 1,000 acres of it were eligible to be placed on the National Register of Places.

One of the other sites in need of preservation was the Hook-Powell-Moorman Farm, which the group notes is an 18th-19th century, 40-acre complex that has multiple buildings. According to Preservation Virginia, the site contains one of the state's few mercantile structures still standing from the 18th century. The farm is listed under numerous historic categories, including architecture, commerce and health and medicine, to name a few. Laser scanners and 3D modeling technology are particularly helpful at preserving historic sites with multiple structures as 3D laser scanning can provide accurate information on all of the site's buildings and locations.

How laser scanning can help
3D laser scanning technology is one of the best ways to map a location or structure. Laser scanners gather accurate data on the as-is conditions of a historic site. The collected data sets can be used to create 3D models of the site. 3D modeling allows preservers to analyze the site. This information can be used to gain insight into the location or building's current condition, which can help preservers understand how to best safeguard the site. In addition, 3D models can help researchers visualize how the historic site might have looked in the past, which can then be used for research purposes or to create educational materials. Even if a site cannot be physically preserved, it does not have to be done forever with the help of 3D laser scanning.