LiDAR & Utility Locates

LiDAR (Light Detection and Ranging) is gaining traction across a lot of applications like autonomous vehicles and most notably for us, utility mapping. When coupled with drones, LiDAR emerges as a potent instrument for collecting precise and high-resolution data, crucial for utility mapping. My colleague Shane Hart has already covered the problem with drones in utility locating but LiDAR opens up a world of possibilities for drone usage in surveying, locating, investigating and engineering. So I'm going to try and stay within the parameters of the technology and what people are actually doing with it now. We have several customers using drones for aerial photography of sites too, which they add to their locate packages and have found useful for damage investigations.

The intricate network of utilities concealed beneath the ground has long posed a challenge in terms of locating and managing underground infrastructure. The advent of LiDAR technology is starting to catalyze a transformative shift, reshaping how underground utilities are mapped and recorded.

Renowned for its capability to capture precise 3D data using laser light, LiDAR has been a game-changer in multiple industries. While its applications in above-ground mapping are well-established, its recognition below the surface is now growing. There are limitations in terms of accuracy but for underground utility locating companies, integrating LiDAR into their operations unlocks a plethora of benefits, revolutionizing their approach to navigating the complexities of subsurface infrastructure. The technology's ability to furnish precise spatial information bridges the gap between what lies hidden beneath the earth and the imperative for comprehensive, accurate data. Basically it's another feather in your cap.

As underground utility locating companies embrace LiDAR integration, they position themselves at the forefront of innovation. The fusion of advanced technology with the critical task of navigating hidden infrastructure reflects the ongoing evolution of the utilities sector. LiDAR is not merely a tool; it serves as a beacon illuminating the path toward a more accurate, efficient, and sustainable future for underground utility locating.

WHAT IS LiDAR?

LiDAR, known for its prowess in capturing detailed three-dimensional data using laser light, has long been a stalwart in above-ground mapping and surveying.

LiDAR operates by emitting laser beams, measuring the time it takes for the pulses to return after hitting an object or surface. This data collection method enables LiDAR systems to create high-resolution maps of the terrain. This capability is particularly effective in utility mapping, where precise spatial information is critical for planning, maintenance, and decision-making.

The cornerstone of LiDAR's impact lies in its unparalleled accuracy. When applied to underground utility locating, LiDAR captures detailed spatial information, providing a reliable foundation for decision-making regarding the location, depth, and type of utilities.

LiDAR FOR LOCATORS

Traditional methods of underground utility locating are often time-consuming and labor-intensive. LiDAR streamlines this process by offering rapid data collection capabilities. With LiDAR sensors, utility locating teams can efficiently cover extensive areas, reducing the time and resources required for surveys. One notable startup using this tech is Exodigo, they use LiDAR in their array of drone based data collection.

I noted in a previous article a quote from Between the Poles, ”"The future of utility surveying is that the certified surveyor no longer needs to travel to construction sites... With modern LiDAR and photogrammetric technology it is possible to record a point cloud of the open trench which can be stored in the cloud and contains much more information than a traditional set of survey points. If the location of all the underground utilities in the proposed construction site is Class A, known to 40 cm accuracy or better, augmented reality technology provides a reliable way of visualizing this data in the field on a handheld device." Surveying and locating are two different specialities and disciplines, but there are some transferable elements between the two. Especially as locating starts to incorporate more and more SUE.

The integration of LiDAR into underground utility locating enhances asset management capabilities. It not only identifies utility locations but also provides a three-dimensional view of their spatial relationships. The integration involves a systematic approach, beginning with assessing current workflows and requirements, developing a comprehensive plan, acquiring suitable LiDAR equipment, and training personnel.?

Brown and Caldwell has applied LiDAR successfully on underground scanning projects that span from inspecting conduits in wastewater treatment plants and standalone process buildings to assessing drainage assets. They have crafted proprietary standard operating procedures for both data acquisition and management, along with a standardized set of deliverables.

“One of the really cool aspects of this technology is that when you’re doing the scan from inside the structure, these data will allow you to ‘see’ the outside of the structure, and the structure’s relationship to the surrounding area. You can stitch multiple scans together and you see how multiple structures are tied together from the inside out. Plus, you can often see all the surrounding structures, like houses, the slope of a street, and other infrastructure. That’s very powerful information.”

In addition DGT Associates did a proof of concept with SITECO Informatica and Sensors & Software Inc. to “collect simultaneous lidar data above ground and GPR data below the surface,” using a fully integrated trailer system.

INTEGRATION

Efficiency in data collection is a hallmark of LiDAR technology, streamlining surveys and optimizing resource utilization. Protocols for combining LiDAR data with existing underground utility records must be established, ensuring seamless integration within the company's Geographic Information System (GIS) or data management platform. Workflow optimization is crucial for maximizing the benefits of LiDAR technology in mapping, asset management, and vegetation detection.

One of the key advantages LiDAR brings is its unparalleled accuracy in mapping, contributing significantly to enhanced safety measures. Accurate mapping minimizes the risk of accidental damage during construction or excavation activities, ensuring the protection of infrastructure, workers, and the surrounding community.

The process of overlaying underground utility data on LiDAR-captured imagery involves a systematic, step-by-step approach to create a comprehensive visualization that merges above-ground features with essential subsurface infrastructure information. Firstly, LiDAR data is collected using drones equipped with LiDAR sensors, allowing for the swift coverage of large areas. This proves advantageous for utility companies requiring prompt updates to mapping information or quick responses to infrastructure changes. Subsequently, accurate underground utility data is acquired, detailing information on location, depth, and type from utility records, as-built drawings, or recent surveys. The process ensures a common coordinate system alignment between LiDAR and underground utility data to achieve accurate overlay, employing GIS software when necessary. Both datasets undergo cleaning and preprocessing to eliminate errors, ensuring precision in the overlay. GIS software integration follows, aligning LiDAR and underground utility data based on spatial coordinates. Layer stacking involves using LiDAR imagery as the base layer and overlaying underground utility data with adjusted transparency for clear visualization. Symbolization and styling are then applied to represent different types of utilities, enhancing visual clarity. Depth variations are visualized using techniques like color gradients, contour lines, or 3D symbols. Data validation involves cross-referencing known locations of underground utilities with the integrated dataset to validate accuracy. Finally, documentation and communication of the overlay process are conducted effectively, including clear legends and labels to aid user understanding. We can bring this information into Utilocate and attach into your locate package so that end users get a deliverable that is much, much more than just a locate sheet or a map.

By following these steps, underground utility locating companies can successfully integrate LiDAR data, creating a comprehensive visualization that enhances decision-making, planning, and management of utilities in each area.

CONCLUSION

The integration of LiDAR technology into underground utility locating companies signifies a transformative leap forward in the industry. As these companies embrace the precision, efficiency, and safety benefits that LiDAR offers, they position themselves at the forefront of innovation. The marriage of advanced technology with the critical task of navigating hidden infrastructure beneath our feet is a testament to the ongoing evolution of the utilities sector, where LiDAR is lighting the way to a more accurate and sustainable future.

Despite the various benefits associated with incorporating LiDAR on drones, it is crucial to take into account factors such as expenses, data processing needs, and regulatory limitations when deploying this technology for utility mapping. Continuous progress in both LiDAR and drone technologies holds the potential for enhancing capabilities and cost-effectiveness in the foreseeable future.?