Geospatially Measuring & Modeling an Israeli Archeology Site Nearly 2,500 Years Old

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For thousands of years this site has been called by Bedouin’s "Beit Lehi," translated from Hebrew meaning "House" or "Ruins of Lehi" and Lehi meaning "jaw bone." Located approximately 25 miles southwest of Jerusalem on an Israeli military base, soldiers discovered this ancient subterranean site while constructing a road near the West Bank in 1969. The site is now thought to be an ancient village or city of some significance with reference made to it by the famed ancient historian Josephus Flavius. The site is also the traditional site of Samson’s Well where a thousand Philistines were killed by Samson with the jawbone of a donkey as recorded in Judges 15:19. So far, excavations have shown that the site dates back nearly to the Iron Age (500 BCE), with the exception of Samson’s Well, which dates to approximately the 12th century BCE.

The non-profit Beit Lehi Foundation (www.beitlehifoundation.com) was setup in 2005 to "advance the understanding and awareness of the general public of ancient religious history associated with this site through scientific research and education." Because of this mission and recent excavations completed on the site in 2010, the foundation president, Alan Rudd, asked the Engineering Graphics and Design Technology department at Utah Valley University (UVU) (www.uvu.edu) located in Orem, Utah (www.orem.org), to get involved with designing and constructing a visitor’s center, parking facility, pedestrian pathways, and other on-site public and preservation facilities, as well as obtaining some archeological survey information. UVU’s efforts are now directed by Darin Taylor, a Drafting Technology professor who has made the project into an official UVU study abroad program which offers Drafting, Geomatics, Digital Media, and Construction management students and faculty an opportunity to get engaged in an international project where they can apply skills and knowledge they have learned in school.

Background
Utah Valley University (UVU) first got involved with the Beit Lehi, Israel project when Alan Rudd, President of the Beit Lehi Foundation contacted Darin Taylor, then Department Chair for Engineering Graphics and Design Technology (EGDT). Alan learned of the unique skill sets the EGDT students and faculty possess. These students are capable of doing the initial site surveying, mapping, and facilities and infrastructure design to accommodate a visitor center with gift shop, theater, site walkways, parking lots, and roadways for tour buses and vehicles. The Digital Media department faculty and students were also included to help film a site documentary focusing on the EGDT students and faculty as they worked on the project, as well as produce a movie that would eventually tell the story and at least part of the known history of the site. The Construction Management department students and faculty may be involved in the future. UVU administration consisting of Ernie Carey, Dean of the College of Technology and Computing, Larry Marsing (retired), Associate Dean of the School of Technology and Construction, and Darin Taylor, Department Chair of the EGDT department visited Israel and the Beit Lehi site at the invitation of the Beit Lehi Foundation to analyze the practicality, cost, and safety of the project for their students and faculty.

During this analysis period Danial Perry, Associate Professor and Licensed Surveyor from the EGDT department, engaged in a conversation with Oren Gutfeld, Chief Archeologist for the Beit Lehi site regarding the possibility of 3D laser scanning in addition to the surface surveying required for the site infrastructure and facilities. Dan has been scanning since 2001 using a Leica GeosystemsTM, Cyrax 2500® laser scanner and was familiar with what could potentially be done with archeological sites. Oren became enthusiastic about the possibilities of introducing 3D laser scanning technology to archeology. Oren mentioned this technology, the conversation with Dan Perry, and the possibilities scanning could provide to Dean Carey, who came home from Israel not only excited about all the wonderful learning and teaching prospects the project could provide but also determined to purchase a 3D scanner for the school and the Beit Lehi project. After approval from UVU was obtained and an agreement made between the university and the Beit Lehi Foundation, Darin Taylor became the project leader who currently sits on the Beit Lehi Foundation board, and Dan Perry became lead surveyor and scanner for the project.

The scope of the project expanded to include not only conventional surface surveying using GPS, Total Stations, and Automatic levels, but also 3D laser scanning using a Leica GeosystemsTM C10®. The C10 is used to scan the entire ancient and recently excavated subterranean facilities including the Olive Press, Ritual Bath (Jewish Mikveh), Byzantine Chapel, and Columbarium’s (anciently used on this site as a place for the raising of doves and/or pigeons).

Surveying and Scanning the Archeological Dig Site
The most important task in starting a site survey is to establish a good survey control network that all additional site surveys, including scanning, could be tied to this same network. During the first year (2010), the UVU team consisted of faculty Darin Taylor, Dan Perry, and Paul Cheney from Digital Media (DGM) along with two DGM students and four drafting/surveying students. While surface control was being established based on assumed coordinates (in feet) by Darin, a few students, and a total station, Dan and two other students began scanning the Olive Press and Ritual Bath. These two facilities had recently (previous 3 years) been fully excavated revealing three olive presses, one pressing/grinding stone, and a limestone quarry at the bottom of the press area.

All the subterranean facilities on this site and in this area of Israel were carved out of a soft limestone material lying below a hard limestone 6­9 feet (2­3 meters) thick above which is a 0.5­1 meter thick layer of topsoil. This hard crust serves as an excellent and reliable ceiling for these manmade underground installations some of which were carved as early as 400 BCE. These facilities had various purposes depending on the need of the occupants, but all were carved from soft limestone material, which made for relatively easy digging. These facilities were much cooler than working on the surface, which can sometimes get as hot as 110º F (44ºC). The Leica C10 had no problem obtaining good reflective surface data from this material, but great care was taken in obtaining accurate registration targets to improve the overall accuracy of the registered point clouds. Over 10 million data points were obtained for the Olive Press and Ritual Bath together. A medium scan resolution setting was selected as a trade-off between speed and resolution and considered the point loss in migrating to Leica GeosystemsTM Cloudworx® software for subsequent drafting performed by UVU students and also required by the archeologists.

The Olive Press consists of a large main room approximately 6.4 meters tall, 9.3 meters at its widest point and 10 meters at its longest point. The temperature working conditions in this underground Olive Press are a comfortable 75º F (24º C) compared to 95º (35º C) on the surface. The Olive Press was completed in about 10 hours with 11 different scanner setups, some of which were not ideal given the difficulty of the areas to be scanned, but still, good data was still obtained.

The Ritual Bath (Jewish Mikveh) was scanned next, which is approximately 5.0 meters tall, and 4.8 meters square
with 7 stairs across the width of the room, beginning at the entrance and descending to the bathing area. The Ritual Bath area only took 2 hours to scan using 3 scanner setups. During post processing, the Mikveh was used as a sample, showing of the type of 3D modeling that the UVU team could provide to the Beit Lehi Foundation. From this model, a scaled 3D print of the Mikveh was produced using a Dimension® EliteTM 3D printer for visualization purposes. This printed model was well received by Oren Gutfeld, the Chief Archeologists and the creation of a scaled model of the entire village showing the relationship of the subterranean facilities to each other and to the surface of the site is anticipated.

A small area known as the Christian Chapel chiseled out of the soft limestone in approximately 300­400 CE was scanned next, along with a nearby ancient donkey stable. All scans were again registered to each other using the Leica Geosystems® 3" and 6" rotating flat targets and subsequently registered to the surface survey control set by Darin Taylor and his team. While the UVU scanning and surveying teams were busy doing their work, the Digital Media team shot several hours of video footage of our students working as well as documenting other aspects of the site, including a panoramic view of all the excavated subterranean facilities to-date. (See "Site Panorama" located under the "Links" navigation bar at www.beitlehifoundation.org). Throughout the 3½ days on the site, the Drafting and Surveying students traded off between the scanning team and the survey control team, thereby allowing each student a chance to get some exposure to conventional survey instruments on the surface and the new C10 laser scanner underground.

Second Excursion, May 2011
The 2011 excursion carried a similar purpose as in 2010, but this time, the team consisted of only 3 faculty and 3 students. This worked well because almost the entire workload was centered on 3D laser scanning using the C10TM. With the large columbarium fully excavated the previous 2010 dig season, several days were spent scanning its sprawling underground area. At approximately 16 meters wide, 17 meters long, and 5 meters tall, this columbarium once held approximately 2000 pigeons/doves, making it the largest and oldest facility of its kind in the world. The post-processed models and 3D prints are still in production.

After completing this facility, a tower foundation was scanned. Located on the surface of the site, the foundation clearly belonged to a watch tower which oversaw the region to the west and south of the village. In fact, this particular facility is mentioned in the ancient historical writings of Josephus Flavius and Christian Priests, which is how Oren Gutfeld identified this city as the City of Zedek built during the early Byzantine era.

Third Excursion, May 2012
This excursion consisted of the largest UVU group yet to work on the site. This time the team carried not only the C10 scanner and the Spectra Total Station, but also an automatic level, and because of Perkins Grant funding, a Topcon GR3 (Base) and Topcon HiPer II (Rover) GPS system. This equipment is also used for course instruction at the university and had proven to work well on the Beit Lehi dig site.

With GPS, the team checked control monuments, acquired data on trails and roads, and general terrain. Prior to departure, Dan Perry transformed the previous control data to actual Israel coordinates and made least squares adjustments comparing previous survey control work set by Darin Taylor and the archeological survey employed by the Foundation prior to UVU’s involvement on the project. This data along with the previously set control monuments matched very well. Another total station survey control crew worked to expand the survey control network to include the area to be encompassed by a visitor’s center, parking lot, and entry road. The automatic level was used to run several level loops between control points to ensure appropriate vertical control accuracy of the horizontal control network. During post-processing of data back at UVU, the data was adjusted slightly for best fit horizontally and vertically, thus providing the site with acceptable survey accuracy for future survey work and construction.

The 3D scanning crew spent time scanning the ruins of the Byzantine Chapel built on this site in approximately 300­400 BCE and located on the western edge of the old village. This facility was built above ground and consists of several rooms, cylindrical columns in the basilica, apse, olive press, wine press, baptistery, and a beautiful, intricate mosaic floor throughout every room, depicting various animals, plants, fruits, and people. The scan data from this facility could possibly be used to do some site reconstruction and create a fully reconstructed virtual model as well as a 3D print of the structure. A minimal amount of scanning was done on others areas of the village because excavation had not been completed at the time of the excursion.

Summary
About a third of the site has now been surveyed using a conventional Total Station and GPS, resulting in an accurate control network and a site and topographic map from which to generate the future design of a visitors center, parking lot, entry road and other important site facilities. All of the currently excavated facilities have been scanned with the intention of producing archeological grade site plans and sections of each facility along with 3D models and prints of the same. The archeological work has been collaborated with the Hebrew University of Jerusalem where Oren Gutfeld is a professor. The Israeli Antiquities Authority (IAA), the Israeli Tourism Department, and the Beit Lehi Foundation are very interested in the progress made by the UVU Engineering Graphics and Design Technology department faculty and students on this site, and they anticipate it will soon become one of the premier tourist sites in southwest Israel.

The future of this project, like many others of its kind, are heavily dependent on charitable contributions needed for excavating and documenting the remaining 90% of the site. UVU students and faculty in cooperation with the Beit Lehi Foundation officers and staff expect to be working for many years into the future on this geospatially challenging, exciting and interesting ancient village of Beit Lehi/City of Zedek located in the beautiful, serene Judean hills of Israel.

Danial L. Perry, PLS, MBA, has more than 15 years of field experience as a surveyor in Oregon, Idaho, and Utah and is currently employed as an Associate Professor and Geomatics Program Coordinator at Utah Valley University located in Orem, Utah. For more information about UVU, the UVU Geomatics Program, and/or the Beit Lehi project please email Dan at perrydl@uvu.edu or visit their website at www.uvu.edu/geomatics.

A 1.642Mb PDF of this article as it appeared in the magazine—complete with images—is available by clicking HERE