Introducing the Dubai Metro Blue Line Project
The Dubai Metro Blue Line is a major expansion of the Dubai Metro network. Currently under construction, it is scheduled to open in September 2029. Spanning approximately 30 km and featuring fourteen stations, the line will include underground sections, elevated viaducts, and Dubai Metro’s first bridge crossing over Dubai Creek.
The contract for the Dubai Metro Blue Line project was awarded to the Mapa Limak CRRC Consortium, a partnership between three Turkish and Chinese companies: MAPA, LIMAK, and CRRC. Within the organization, Senior Survey Manager Murat Pehlivan and his surveying team are responsible for acquiring high-precision data of both new and existing project structures. The consortium uses this data for construction activities as well as for producing and coordinating engineering design and BIM models.
Project Sites and Data Acquisition Method
Rather than relying on traditional surveying methods, the surveying team chose 3D laser scanning as its primary data acquisition method. This enabled the team to capture large and complex structures at a very high level of detail within a three-month timeframe. Scanning work included two existing metro stations, Creek and Centrepoint, formerly known as Rashidiya. These stations are part of the existing Green and Red lines, which will be connected by the new Blue Line.
Each station covers an area of approximately 13,000–14,000 square meters. In addition, the team scanned the R11 multi-story parking structure, covering 150,000 square meters. Scanning work included both the interior and exterior of each facility, including access and entry gates, footbridges, parking areas up to the rooftop level, and bus movement zones. Upcoming scanning work for the Blue Line will include underground tunnels, elevated viaducts, and stations.
Project Deliverables Overview
The three-month scanning campaign forms part of a longer-term project in which the surveying team delivers high-accuracy point cloud files of existing metro stations and structures to the Mapa Limak CRRC Consortium. Data processing runs in parallel with ongoing scanning activities. This allows both to progress simultaneously without waiting for all structures to be completed.
In addition to scans of existing infrastructure, the team also captured data intended to support the construction of future structures to be built by MLCC Design & BIM department as part of the Blue Line project. MLCC’s Design and BIM department superimposed the 3D models of the existing structures with the interconnecting structures that will be built in the Blue Line project. These models were utilized to identify any inconsistencies within the existing models and will be built ones.
CRRC’s Design and BIM department provided Murat Pehlivan’s surveying team with 3D models of the existing stations. These models were superimposed onto the team’s scanning data to identify any inconsistencies within the existing models.
“Having an accurate colorized 3D model of all structures is what makes the 3D scanning data valuable,” says Pehlivan. “Superimposing the scan data with the design data enables us to detect even the smallest discrepancies.”
Deploying the Topcon CR-P1 and Collage Site Software
After deciding to use laser scanning for capturing 3D data of the existing structures, Pehlivan began searching for a suitable scanning solution. He was particularly interested in testing Topcon’s latest laser scanning technology, the CR-P1 3D laser scanner, in combination with Topcon Collage Site software. The software allows users to scan, process, and view georeferenced point clouds directly in the field.
“After evaluating the available options, the CR-P1 came out on top for its combination of speed, accuracy, and field-processing capability using Collage Site,” explains Pehlivan. “Another feature I really liked was the ability to immediately review the collected data after completing a scan session using Collage Site. That allowed us to repeat scans immediately if there was any disruption in the data while still onsite.”
A product demonstration was arranged by Topcon and UAE-based Topcon dealer Al Fajer Trading LLC, which left a strong impression on the surveying manager and his team.
“Setup time was less than one minute and required nothing more than mounting the scanner on a tripod,” says Pehlivan. “The user interface was easy to understand, and within 15–20 minutes the surveying team was capturing data onsite without needing additional support.”
Daily Scanning Workflow Overview
The surveying team followed a structured daily workflow to acquire scanning data. First, a series of high-accuracy reference points was generated from the main surveying network and transferred indoors when scanning work took place inside a structure. For outdoor work, reference points were generated directly across the surfaces being measured.
More complex structures, such as facilities with numerous corridors, required additional reference points and therefore more setup time. Next, a Topcon GT-1200 robotic total station was used to transfer the control points generated earlier. Finally, the CR-P1 scanner was set up and scanning operations began.
Ensuring High Positional Accuracy
The robotic total station played an important role in ensuring positional accuracy for the structural and architectural elements within the metro stations. Because the Blue Line is still under construction, surveying activities captured both existing and newly built structures.
These interconnected structures required a high degree of accuracy, which explains the use of the GT-1200 to improve field efficiency and accelerate measurements.
Field Operations
The efficiency of the CR-P1 enabled the team to rapidly capture large volumes of data across the project’s complex station environments. Numerous scan positions were established as required by site conditions, visibility constraints, and the level of detail needed for each structure. The data was processed simultaneously using Collage Site, aligned with real-world coordinates, and delivered to MLCC’s Design and BIM department for integration into a comprehensive 3D BIM model.
The accuracy reports from Collage Site helped save the day on site when multiple interpretations of the reality between design and survey team arose. “When we were told about a discrepancy between the BIM models and our scanning data, Collage Site’s accuracy reports allowed us to compare both data sets and we found that the scans proved to be accurate and saved us a day of possible rework.”
Scanning operations were subject to a range of health, safety, and security restrictions. Collage Site’s real-time review capability allowed the team to identify, and re-scan any affected areas on the spot, eliminating the need for costly site revisits.
Working in confined spaces generally did not affect scanning operations, except when metro passengers moved through the scanning area. The team scheduled most of their scanning during off-peak hours to maintain data integrity across live operational stations.
Although the scanning activities initially followed a strict schedule, the team gradually became more efficient and eventually moved ahead of schedule by capturing large volumes of data in a relatively short time.
“The efficiency gains of using laser scanning instead of traditional methods were significant – what would have taken a three-person team working between two shifts up to six months was completed in just three months by a team of two. A single shift operation that cut labour requirements by approximately 60%.”, explains Pehlivan.
This project demonstrates how smart workflows can help surveying teams improve productivity onsite, reduce site revisits, and process data directly in the field rather than back at the office.
The benefit of setting a custom processing range
Collage Site has a useful efficiency feature that lets users set a custom processing range during data processing, so the team could focus only on the area of interest instead of processing everything.
This approach helped avoid entanglement, reflective elements, and repetitive surveys by incrementally building upon previous measurement points while ensuring that all data aligned correctly.
After-sales support also proved to be an important factor when the surveying team encountered problems in the field.
“Onsite, when there’s a problem, you can’t simply stop the project — you have to find a solution,” says Pehlivan. “Support from local Topcon dealer Al Fajer was available 24/7, and within two hours a technician was onsite helping us resolve the issue. That was extremely important for us.”
Shortening Commuting Times
The Dubai Metro Line Project was created in response to the rapid growth of eastern and northeastern Dubai, areas that previously lacked direct metro access. As a result, residents relied heavily on cars, generating significant traffic toward areas such as Downtown Dubai and Business Bay.
The Blue Line is expected to shorten commuting times, improve access to jobs, support university mobility, and reduce pressure on major highways.
The project will also include Dubai Metro’s first bridge crossing Dubai Creek and a new iconic elevated station at Dubai Creek Harbour, planned to reach 74 meters in height. The station is expected to become a landmark attraction for international visitors as well.
“Thanks to this metro project, daily commuting times can be reduced from two to three hours down to just 30 minutes,” adds Pehlivan. “This will benefit society as a whole in many ways.”
The combination of the Topcon CR-P1 3D laser scanner and Collage Site software helped Pehlivan and his team to be more productive and efficient for such a large project with complex structures, and meet accuracy requirements “For large scale projects like this with a tight time schedule and high accuracy requirements, using the latest scanning technologies is not an option, but a necessity.” concludes Pehlivan.
