Capturing Fast and Accurate Data for Highways England Area 3
Sun Hill Surveying and Engineering Ltd is a specialist Land Surveying and Engineering company focusing on the civil engineering sector throughout the UK. Working closely with Leica Geosystems for over 20 years, Sun Hill made a significant capital investment in the Leica Pegasus:Two in August 2015.
Soon after this investment in mobile mapping technology, Sun Hill was approached and commissioned by Kier to survey 119 sites on behalf of Highways England Area 3. Area 3 is Highways England’s second largest road network carrying around 10 percent of the country’s overall traffic flow. It includes the M27, M3, M4, A3, A303 and the Hindhead Tunnel which provides the main link routes between several major towns and cities including Oxford, London, Reading, and Swindon, in the north; and Bournemouth, Southampton, and Portsmouth, in the south.
Reducing Traffic Management Installation
The large scale project required detailed topographical surveys of the carriageway and verges, with each survey measuring 600m long for the design and future replacement of road signage for clearer visibility across the gradients on the road. The topographical survey features for the design included the surveying of the carriageway extents, road markings, crash barriers, drainage channels, top of kerbs, gullies, kerb wells, verge levels, ironwork frames, sign locations, traffic loops, overhead cables, electrical boxes, railings, fences, steps, bridge soffit levels, and bridge pier positions.
To survey these sites traditionally, a long and protracted operation using laser scanners, total stations, and GPS, would have been undertaken to collect thousands of points of data per day. Typically, this would take a surveyor around 2 days in the field per site to complete. Also to survey this many sites would have required 119 individual traffic management installations. With a project of this size, there is a significant health and safety risk associated with all involved, to personnel being both in the carriageway and in the verge during all the day and night times. A safer and more cost effective method was needed to deliver the project on time and in budget.
Data Capture through mobile mapping
Using the mobile mapping process and Leica Geosystems’ technology provided a huge benefit to the Area 3 Highways England project. Access to all sites was left clear with no road closures required as the Leica Pegasus:Two acts in the same way as any other public vehicle when 
collecting the 3D geospatial data. In total, the surveyors travelled more than 6,000km using the Leica Pegasus:Two collecting millions of points per second. There caused no disruption to the road network as traffic management was not required, allowing traffic flow to continue as normal.
Safety to survey personnel was considerably improved using mobile mapping as no surveyors or traffic management crews were needed in the road as all the data was captured from inside the safety of the vehicle. The virtual surveyors – real surveyors working only from the office – were able to create traditional topographical surveys from the point clouds and images.
Results and Benefits
Mobile mapping provided a rapid data capture solution for Kier, saving them time, reducing safety risks and maximising value by reducing a 200 plus field day project to only 12 days with no traffic management. Furthermore, all 119 sites were surveyed and delivered to Kier a week before the final deadline, thanks to the speed of accuracy delivered by using the Leica Pegasus:Two. Sun Hill was able to deliver this project with less than 20mm absolute accuracy. The surveys were then delivered in a staggered program, allowing sites to be prioritised.