In the U.S., commercial real estate transactions often require property surveys that follow standards jointly developed by the American Land Title Association (ALTA) and the National Society of Professional Surveyors (NSPS). In addition to accurately marking property boundaries, ALTA/ NSPS surveys call for comprehensive information on the location and characteristics of improvements on the property. The work to document complex, high-value properties presents unique challenges—and opportunities— for land surveyors.

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Lidar model of the survey provides real-world version of the 2D drawing. Utilities and pavement markings can be confirmed using the scanning data.

When Taylor Denniston receives a call for a commercial property survey, he sets in motion a chain of field and office work that culminates in a completed ALTA survey. A professional land surveyor with Smith Roberts Baldischwiler LLC (SRB) in Oklahoma City, Denniston focuses on transaction surveys. The demanding work entails thorough research, accurate positioning and high attention to detail. ALTA surveys often come with tight schedules, long lists of requirements (including measurement precision), complicated properties and myriad concerns from buyers and sellers, attorneys, title companies and lenders. While efficient fieldwork is important to an ALTA survey, Denniston said the priority is gathering complete data. It’s not unusual for crews to spend multiple days on a project, capturing features that range from buildings and utilities down to stripes in parking areas. Even then, they might overlook things on complex sites. Incomplete information or questions from clients often result in revisits that add time and cost to the survey.

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Colorized point cloud provides aerial view of the site. Building overhangs and details can be identified and measured using the 3D data

A Flexible Solution

Recognizing the potential for increased efficiency in ALTA work, SRB turned to the Trimble SX10 Scanning Total Station. The SX10 combines the functionality of a robotic total station with highprecision 3D scanning. The instrument is providing productivity gains both in field and office aspects of the surveys. In the field, SRB crews use the SX10 to make precise measurements to boundary markers and property features. They can then use the scanning function to collect dense data over the entire site. When the field data arrives in the office, technicians process both the survey measurements and scanning data in Trimble Business Center software to produce 3D point clouds that are referenced to the property boundary. From there, they can develop the drawings and reports to meet ALTA standards.

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The scan data reveals details on the building and landscaping needed to meet ALTA/NSPS standards

By combining surveying and scanning, the SX10 provides a powerful tool for ALTA and property surveys. The instrument uses survey workflows already familiar to field and office staff, helping them to quickly come up to speed with the solution; SRB crews needed less than a day to become proficient with the scanning process. Denniston described a survey of a bank building that had unusual architectural features. “It was very fancy and had numerous overhangs,” he said. “Using a total station, it would have been very difficult to give the office techs an idea of what it actually looked like. We used the SX10 and were able to capture the whole site in 3D.” The office technicians could use the point cloud to understand the building layout. They were able to create plan views of the site and determine if there were any encroachments from overhangs.

Moving Ahead of the Competition

The field crews completed the survey in just one day, a time savings of more than 50 percent over Denniston’s original estimate. Additional savings came during the drafting phase of the survey. “We didn’t need to shut down a crew for a few hours just so they could work with the drafters to make sure the drawings accurately depicted the site,” he said. Using the 3D data enabled them to answer questions quickly and add new information (or features the survey crew missed) to drawings without returning to the site. The SX10 gives SRB a competitive advantage. It enables SRB crews to capture more information with less time on site. “We are moving more and more towards this type of data collection,” Denniston said. “The SX10 delivers tangible benefits to our clients.”

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The finished ALTA survey provides a large amount of information. Typical deliverables are 2D drawings in electronic format.

“We are able to do things that we wouldn’t be able to accomplish accurately with traditional surveying methods. The SX10 is just much easier and faster.” — Taylor Denniston, PLS, GISP Director of Surveying and Mapping Smith Roberts Baldischwiler LLC

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