ASI Group

ASI’s Global Services

35 Years of Trusted Underwater Services

Underwater infrastructure requires extended inspection, detailed repair work and ongoing maintenance activities to prolong the operational life and efficiency. ASI owns and operates a fleet of remotely operated vehicles (ROVs) and various underwater platforms to accomplish a variety of underwater tasks, including inspection, cleaning, and rehabilitation. ASI provides services globally with the expertise of a multidisciplinary team specializing in underwater investigations and remote technology. Our engineers, project managers and technicians are backed by a fleet of advanced robotic vehicles equipped with the latest in imaging, surveying and inspection technologies to support underwater infrastructure condition assessment needs.

These customized platforms can be outfitted with digital stills cameras, video cameras, multiple sonar technologies, ultrasonic thickness instruments, and custom tooling packages. ASI is a leader in the application of sonar technology in making highly accurate 3D models of underwater infrastructure.

ROV Technician
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Global Service Offerings

Guinness World Record for longest tunnel survey

Long Distance Tunnel and Pipeline Inspections
Using Remotely Operated Vehicles (ROVs)

ASI has inspected over 720 km (447 miles) of tunnels and pipelines globally using ROVs equipped with fiber-optic telemetry for collection of real-time video and sonar imaging. This allows safer, less costly, and less time-consuming long-range inspections of tunnels over 10 km (6.2 miles) in length. The company has inspected some of the longest water tunnels in the world, including one 120 km (72 miles) in length with unprecedented remote interventions of
10 km (6.2 miles) from single entry points.

Tunnel Inspections

Our experience and expertise in underwater technology has made ASI a world leader in long tunnel/pipeline inspections without the need for dewatering. Remote inspections provide a safer and cost-effective alternative to dewatering tunnels and pipelines. ASI’s comprehensive fleet of ROVs supports the inspection of tunnels and pipelines in a flooded state, saving time, money and avoiding the risks associated with dewatering these structures.

Dam Inspections

Safety is of utmost importance to ASI. We understand that thorough assessment of the condition of your underwater assets is crucial for dam safety assessment. For decades, ASI has gained global recognition for researching and developing remote techniques for underwater dam inspection, repair and maintenance. ASI has developed methodologies that use sonar systems to capture and present pertinent data for asset management with limited impact to plant operating conditions.

Our global team of ROV pilots, technicians, engineers and certified hydrographers are well-versed in underwater data collection and have gained vast experience working at numerous dam sites across the globe. ASI’s inspection data can identify offsets, misalignments of concrete slabs, leaks, silt accumulation, undermining and spalling, among others. This crucial information helps identify conditions that may adversely affect the safety and functionality of a dam and associated underwater structure. In addition, comparative analysis of repeat inspection data can help identify trends in features of interest, assisting in the development of maintenance and repair programs.

Gate Slot Inspections

Specialists at Hydro-Québec’s (HQ) research institution have been pooling their expertise in mechanics, IT and electronics to develop solutions for more than 20 years. In early 2021, HQ released their latest technology, WireScanTM, and awarded the contract for commercialization of the system to ASI.

WireScanTM is a unique technology, developed specifically for hydroelectric facility structures, such as gate slots and stop logs. The system collects data both above and below the water line, outputs immediate 3D point cloud data for review, and uses plumb guide wires to measure verticality.

WireScanTM produced engineering-level 3D scans, providing dam owners with detailed data that is critical for condition assessment at facilities around the globe.

Global Industries Served

Hydropower, Public Utilities, Ports & Piers, Nuclear Power, Renewable Energy, Manufacturing, Mining, Construction, Oil & Gas


Merry Dang - Vice President, Business Development

Merry Dang (she/her), Vice President, Global Business Development

Office: +1 905.643.3283 x.246  |  Mobile: +1 905.321.4689

Global Long Distance Tunnel Inspections

Global Map of Long Tunnel Inspections

Project Reference: Hydropower

Comprehensive Dam Condition Assessment, Inspection and Survey Services

ASI was subcontracted to provide underwater services using remote inspection technologies, bathymetric surveys, and two-dimensional (2D) sonar imaging at a hydroelectric facility. The objectives of this project were to conduct a general condition assessment of the power conduit, penstocks, and intake trash racks at the dam, as well as a bathymetric survey of the surrounding reservoir bed.

ASI conducted the external survey using a surface vessel to collect 2D imagery of the trash rack structure and high-resolution 3D multi-beam sonar data of the entire upstream toe and dam face. Additional imagery of the trash rack was collected using an ROV equipped with a high definition camera, imaging sonar, and profiling sonar.

For the internal power conduit and penstock inspections, an ROV was deployed equipped with cameras, imaging sonar, inertial navigation, and high-resolution multi-beam sonars. Along with the video and 2D sonar data, ASI assembled a 3D point cloud model of the entire tunnel. Ultrasonic thickness data was collected in the metal penstocks and reported accordingly.

The inspection data presented mapped elevations of the reservoir surrounding the dam and a detailed model of the dam face, intake structure, power conduit and penstocks, providing both an overview of the infrastructure’s condition as a whole and a detailed account of each critical area. Subsequently, this data was further combined with aerial lidar point cloud data to create a complete model of the asset above and below the waterline, internally and externally. The reported data, which included a written report, edited inspection video, video and sonar stills, bathymetric contour maps and 3D point cloud data, provide an accurate baseline for comparison to past or future inspections and is entirely repeatable to assist with monitoring and maintenance needs.

Global Dam Inspections for Safety, Dam Overview 3D Point Cloud
Global Dam Inspections for Safety, Dam Reservoir Bathymetric Map
3D Point Cloud of Conduit Trifurcation, Dam Safety and Inspection

3D point cloud and lidar overview model of dam

Bathymetric contour map of surrounding area

3D point cloud of the conduit trifurcation

Flythrough Video

ASI Canada is ISO certified for quality management and occupational health & safety management.

At ASI, safety is at the forefront of everything we do. We believe in:

• Our people – our team produces an injury free culture
• Safety as the core of everything we do
• Preventability of all injuries
• Always taking the time to do the job safely
• Continuous education in safety
• Empowerment and our commitment based approach to safety
• Zero fatalities or serious injuries

• Zero damage or destruction to company property or equipment
• Increased productivity through reduction of injuries
• Our reputation for working safely
• Keeping safety paramount in everyone’s daily activities
• Recognizing safe work practices
• Improving morale and productivity

ASI is registered with numerous third-party registrants as a qualified vendor including
ISNetworld, Avetta,
ContractorCheck and Cognibox to effectively meet our clients’ QHSE needs.