Inspection ROV
Discover cutting-edge solutions from leading global suppliersSEAMOR Marine’s underwater remotely operated vehicles (ROVs) are a key tool for evaluating infrastructure integrity, offering an efficient, non-disruptive solution.
The ongoing crisis in North America’s civil infrastructure requires innovative approaches to maintain safety and functionality, with ROVs delivering precise inspections, minimizing downtime, and enhancing overall operational efficiency. Read more >>
The Problem
North America’s civil infrastructure, including tunnels, bridges, and dams, is under significant strain due to age and increasing demand, especially in high-density areas. Municipalities face urgent challenges, exemplified by emergency situations like the recent public water shortage in Calgary, Alberta.
Effective methods are needed to assess the integrity of civil infrastructure, particularly those in high-stress environments or submerged locations.
Disruptions caused by service interruptions during inspections are a serious concern. Therefore, assessments must not only be thorough and accurate but also aim to minimize or eliminate service disruptions to the public.
Toronto Water faced such challenges when it was necessary to inspect the Cross Harbour Watermain Tunnel (CWT), constructed in 1905 and last inspected in 1978 by Alebery, Pullerits, Dickson, and Associates.
The CWT is a key conduit for the city’s drinking water, running beneath Toronto Harbour from Mugg’s Island to the John Street Pumping Station. In 2018, Toronto Water awarded a contract for a vulnerability and capacity assessment of the tunnel to General Diving Contractors Inc. (GDC) and R.V. Anderson Associates Limited (RVA).
The Solution
For the inspection, SEAMOR Marine’s Chinook ROV was chosen to perform the survey. This ROV, capable of operating at depths of up to 600 meters, was outfitted with additional components, including a high-definition camera, a standard-definition camera, an Imagenex Model 831a Digital Pipe Profiling Sonar, and LED lights.
The Chinook ROV was deployed from a barge, serving as a staging platform, and was guided through a vertical sheave into the shaft to ensure smooth tether management.
A sample image from the Chinook ROV’s video feed
Since human divers have limitations in both depth and time underwater, the Chinook ROV significantly enhanced the efficiency of the operation carried out by GDC and RVA by enabling longer and more comprehensive inspections. Beyond operational efficiency, the ROV minimized safety risks to divers, as the survey was conducted in an active water flow environment.
High-definition video footage captured by the Chinook ROV showed that the CWT’s structural condition was similar to findings from the 1978 inspection, with only minor horizontal cracks observed at the tunnel’s spring line and crown in some areas. New areas of brick deterioration and spring line cracks were also documented in the final report based on the ROV’s footage and data collected from the Imagenex Model 831a Digital Pipe Profiling Sonar.
Conclusion
GDC and RVA identified several key benefits of using SEAMOR Marine’s Chinook ROV for their vulnerability and capacity assessment. Its ability to operate in live flow conditions eliminated the need for service disruptions, and the high-quality imagery provided allowed for an accurate assessment of the tunnel’s current condition.
Additionally, the Chinook ROV’s compact design and six powerful thrusters enabled it to reach areas that human divers could not, while also reducing the overall time and cost of the assessment.
Conducting vulnerability and capacity assessments for public infrastructure, such as tunnels, bridges, and dams, with ROVs like SEAMOR Marine’s Chinook ROV presents a highly effective solution to the civil infrastructure crisis. This approach not only safeguards human divers but also reduces the operational time and costs for municipalities.
