GEOMATIC ASSESSMENT Membership Directory & Buyers Guide 97th Annual Conference Recap WINTER 2017/18

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1 WINTER 2017/18 GEOMATIC NC AWWA-WEA 3725 National Drive, Suite 217 Raleigh, NC ADDRESS SERVICE REQUESTED 2018 Membership Directory & Buyers Guide 97th Annual Conference Recap The official publication of the North Carolina Section of the American Water Works Association (NC AWWA) & the North Carolina Member Association of the Water Environment Federation (NC WEA)

GEOMATIC How Unmanned Aerial Systems Are Changing the Surveying Industry: Comparing Real-World Accuracy and Cost with Traditional Survey Technologies By Christian Stallings, CP, Research &

2 GEOMATIC How Unmanned Aerial Systems Are Changing the Surveying Industry: Comparing Real-World Accuracy and Cost with Traditional Survey Technologies By Christian Stallings, CP, Research & Development Manager, McKim & Creed, Inc. Is a drone the best way to collect data for your project? Unmanned aerial systems (UAS), aka drones, are certainly among the newest geomatics technologies in the industry. UAS offers safe, accurate, cost-effective data collection in areas that are inaccessible or too costly for conventional surveying methods. Licensed and insured UAS pilots can legally deploy airframes into FAA-controlled airspace up to 400 feet above ground to collect data at an accuracy of 5-cm root-mean square-error (RMSE) or better. But is UAS right for every surveying situation? In this article we describe three case studies in which UAS technology was compared with conventional surveying methods. We focused on three applications: a landfill volumetric survey, a beach monitoring survey, and an elevation verification for a private developer. These types of surveys are typically conducted using fixed-wing aerial photogrammetry, aerial lidar, and/or conventional ground surveying. UAS for Landfill Survey To test the efficacy of using UAS technology for volumetric surveys, McKim & Creed teamed with landfill engineers Garrett & Moore, Inc. to survey a 60-acre land clearing and inert debris landfill. Garrett & 58 NC Currents Winter 2017/18

DEM with contours from the landfill site that was surveyed using UAS. The surface model created from the UAS-collected data of the landfill.

The data was verified onsite, and point cloud creation was completed in less than 24 hours.

The project was designed to meet ASRPS Positional Accuracy Standards for Digital geospatial Data (2014) for a 5cm RMSEz vertical Accuracy Class, equating to Non-vegetated Vertical Accuracy =+/- 9.

3 DEM with contours from the landfill site that was surveyed using UAS. The surface model created from the UAS-collected data of the landfill. Moore typically relies on aerial mapping data to perform volumetric analyses. Using a 3D Robotics Solo platform equipped with a Sony QX1 camera, McKim & Creed captured the data in less than an hour. The data was verified onsite, and point cloud creation was completed in less than 24 hours. Planimetrics, contours, and volumetrics were processed faster than with conventional ground survey, aerial photogrammetry, or lidar. The project was designed to meet ASRPS Positional Accuracy Standards for Digital geospatial Data (2014) for a 5cm RMSEz vertical Accuracy Class, equating to Non-vegetated Vertical Accuracy =+/- 9.8 cm at 95%. Our results were twice that, at 2.25cm Vertical RSME, equating to 4.45cm at a 95% confidence level. We set eight control tiles prior to the flight and collected 12 independent ground truthing shots randomly throughout the project limits. These were compared to the postprocessed 3D surface to measure the delta on the three axis from the known point to the drone survey. unreliable in highly vegetated areas. In those types of conditions, it may be necessary to supplement UAS with ground survey. UAS for Beach Monitoring During 2016 National Hurricane Preparedness Week, McKim & Creed teamed with geospatial software giant Esri to conduct a proof of concept (POC) for local, state, and federal public agencies. UAS was used to collect topographic data for beach monitoring surveys, which was then matched against conventional land survey data and terrestrial lidar data. The data was compared for accuracy, cost, and delivery time. McKim & Creed again used our 3D Robotics Solo platform, along with SiteScan software, for data collection. Esri processed the data using its Drone2Map software. Results The data comparison showed that, in the correct environmental conditions such as open beaches or moderately vegetated berms and basins UAS outperformed conventional services by producing a more detailed digital elevation model (DEM) more quickly and at a lower cost. In fact, Results This project indicated that UAS can provide significant cost savings while exceeding the accuracy specification for this type of survey. Our results showed that, on average, using UAS for landfill surveys is approximately 10-40% cheaper than conventional ground survey based on the condition of the site, 30-40% cheaper than aerial photogrammetry, and 40-50% cheaper than lidar. UAS does have some drawbacks, however. Data is difficult to capture and A north-south flight pattern was chosen for the landfill with a forward overlap of 78% and a side overlap of 60%. The mission was flown at 400 ft. above ground level, giving a ground sampling distance of approximately 3.5 cm. Due to temperature and wind conditions, two flights were conducted to ensure proper battery failsafe. Flight 1 (in green) included 108 images, while 98 images were collected during Flight 2 (yellow). 59

GEOMATIC McKim & Creed and Esri conducted a POC to test the accuracy, efficiency, cost effectiveness and environmental efficacy of using low-cost, commercial unmanned aerial systems (UAS) for beach

Here, McKim & Creed s Christian Stallings, Certified Photogrammetrist (yellow vest) explains the UAS technology to representatives from local, state and federal agencies, as well as UNC Wilmington,

In the event of a major storm, a UAS survey can be accomplished just days before an approaching storm and again immediately after the storm subsides.

4 GEOMATIC McKim & Creed and Esri conducted a POC to test the accuracy, efficiency, cost effectiveness and environmental efficacy of using low-cost, commercial unmanned aerial systems (UAS) for beach monitoring surveys. Here, McKim & Creed s Christian Stallings, Certified Photogrammetrist (yellow vest) explains the UAS technology to representatives from local, state and federal agencies, as well as UNC Wilmington, Audubon Society and NC Land Trust. One other significant benefit specific to coastal monitoring is the ability for the UAS team to collect massive amounts of data in a short period of time. In the event of a major storm, a UAS survey can be accomplished just days before an approaching storm and again immediately after the storm subsides. we estimated a 60% savings in time and cost when compared to conventional techniques for the site. One other significant benefit specific to coastal monitoring is the ability for the UAS team to collect massive amounts of data in a short period of time. In the event of a major storm, a UAS survey can be accomplished just days before an approaching storm and again immediately after the storm subsides. In addition to the DEM, the UAS has the added benefit of documenting the site with high-resolution (1.5cm) ortho photography. UAS for Earthwork Overages Briar Chapel is a 1,600-acre masterplanned community in Chapel Hill, North Carolina, and is being developed by Newland Communities. When the initial clearing was completed on a 25-acre commercial site within Briar Chapel, The data was processed in Esri s Drone2Map software. Blue dots represent the location where each image was taken and the 3D model is laid over existing imagery. This image was created so that Newland could visualize both the contours, as well as the high-resolution ortho. Inset: At 5 cm, the ortho showed exquisite detail. Capturing the data using conventional surveying methods would have taken approximately two days in the field with a two-person crew. UAS captured this same data in a few hours with the help of a one-person crew to provide ground-control points. 60 NC Currents Winter 2017/18

The test site included two rock jetties. The inset is the 3D model produced from the UAS data, and the background image is a photo of the jetty taken by the drone.

An aerial photogrammetry survey of the entire community site had been conducted by another company several years earlier, and the accuracies required verification.

5 The test site included two rock jetties. The inset is the 3D model produced from the UAS data, and the background image is a photo of the jetty taken by the drone. surveyors were asked to verify elevations. An aerial photogrammetry survey of the entire community site had been conducted by another company several years earlier, and the accuracies required verification. In their field checks, the surveyors discovered some variances, ranging from a few inches to over a foot, between their data and the existing aerial survey. The discrepancies were not consistently low or high, they were just varied. And because the original aerial survey was done with full tree cover, which can sometimes skew survey data, the result was probably within originallycontracted tolerances. Even so, once construction began, the slight differences on paper could quickly turn into mountains of wasted dirt. Flying the site to collect new data would take too long and be too expensive. And on the ground, it would take two field crews approximately two days to collect the data. We saw an opportunity to try out drone capabilities in our type of industry. In our partnership with McKim & Creed, we were trying to find another way to be more efficient, manage the whole design-build process, and be integrative. Hopefully it would be quicker, said Lee Bowman, senior project manager with Newland. 61

GEOMATIC Like its mobile counterpart, aerial lidar offers the benefits of fast, safe, and accurate data collection for wide area mapping and utility corridor mapping.

The instruments feature integrated cameras that allow the photography to be georeferenced and used for mapping.

6 GEOMATIC Like its mobile counterpart, aerial lidar offers the benefits of fast, safe, and accurate data collection for wide area mapping and utility corridor mapping. Other Innovative Data Collection Technologies Robotics Next-generation robotic total stations enable surveyors to use one- or two-person crews, rather than two- or three-person crews. The instruments feature integrated cameras that allow the photography to be georeferenced and used for mapping. This is a huge benefit to the CAD designer when drawing a map, and is a valuable QA/QC tool when checking for missed information. Mobile Lidar Mobile lidar is one of the safest methods of data collection around, provided you re surveying in an area that s navigable by a motorized vehicle. Mobile lidar can collect up to one million points per second, while traveling at posted speed limits. For urban highway design projects with multi-lanes and high-traffic areas, it is hands down the go-to system. The post processed data is accurate to within 0.05-ft. The system is highly flexible as well, and can be transferred to an ATV or boat to collect data in less accessible areas. Chad Burchette conducts a test run of one of McKim & Creed s robotic total stations, which can enable surveyors to use one- or two-person crews, rather than two- or three-person crews. Results Using UAS, a full survey of the site was performed within a few hours. The next day, Newland was presented with an updated survey CAD file of the topo, a high-resolution ortho photo, a classified point cloud of the bare earth, and a change detection analysis to compare the two surveys. The earthwork estimates were adjusted as needed and construction commenced on schedule, with no wasted time, money or fill. Conclusions In each of these three cases, UAS achieved the same high quality 5-cm or better data accuracy of aerial photogrammetry, but the collection times were faster and the process required fewer crewmembers. Additionally, UAS was less affected by weather conditions than other technologies because of the rapid deployment time and quick turnaround. But while UAS is definitely changing the geomatics landscape, it is not always the right tool. For example, returns on cost savings start to diminish once the site gets larger than approximately one square mile. UAS also works best in open areas with limited to no vegetation. In situations where UAS is not the right tool, other technologies may offer the best solution, including: Aerial Lidar Like its mobile counterpart, aerial lidar offers the benefits of fast, safe, and accurate data collection for wide area mapping and utility corridor mapping. Mobile lidar is one of the safest methods of data collection around, and enables surveyors to collect up to one million points-per-second while traveling at posted speed limits. 62 NC Currents Winter 2017/18

The applications for this technology are widespread, and include electric distribution and transmission, roads and railways, aviation, telecommunications, oil and gas, water, forestry and agriculture

7 Aerial lidar is very effective in collecting data for transmission lines. Acquisition platforms and sensors include fixed wing and helicopter-based airborne lidar, along with high-resolution aerial photography using both RGB and infrared digital cameras. The applications for this technology are widespread, and include electric distribution and transmission, roads and railways, aviation, telecommunications, oil and gas, water, forestry and agriculture and local, state, and federal government. Christian Stallings serves as McKim & Creed s research and development manager, and provides technical oversight and management of data acquisition and processing phases, as well as management of all QC processes associated with acquisition and production. He holds a master s in geographic information technology and a graduate certificate in remote sensing from Northwestern University, and has extensive instruction experience in advanced lidar data processing and advanced production workflow from Penn State. 63

UAS to GIS Utilizing a low-cost Unmanned Aerial System (UAS) for Coastal Erosion Monitoring

UAS to GIS Utilizing a low-cost Unmanned Aerial System (UAS) for Coastal Erosion Monitoring Agenda Scope of today s presentation Demonstration Objectives Wrightsville Beach Test Area Masonboro Inlet Jetties